KR20160117863A - A Fingerprint Identifier and a Fingerprint Identifying Method - Google Patents

Abstract

The present invention relates to a fingerprint recognition method and apparatus capable of discriminating a forged fingerprint by recognizing a fingerprint by acquiring not only a shape of a fingerprint but also information about a living body using light beams of various wavelengths.
The present invention comprises the steps of optically obtaining the shape of a fingerprint touched to a contact surface (20); And a step of irradiating light toward the fingerprint and obtaining bio-light information of the finger having the fingerprint in a state where the fingerprint is in contact with the contact surface (20), the method comprising the steps of: When the oxygen saturation calculated from the first wavelength light absorption amount of the first wavelength and the light absorption amount of the second wavelength of blood is within the predetermined range, determining that the acquired fingerprint is a fingerprint of the living body.

Description

FIELD OF THE INVENTION [0001] The present invention relates to a fingerprint identification device,

The present invention relates to a fingerprint recognition apparatus and a fingerprint recognition method, and more particularly, to a fingerprint recognition apparatus and a fingerprint recognition method capable of discriminating a forged fingerprint by recognizing a fingerprint by acquiring not only a shape of a fingerprint but also information about a living body, And a device implementing the same.

 A fingerprint recognition device is a device that identifies a person by recognizing a person's fingerprint. The fingerprint image acquisition method of the fingerprint recognition device includes an optical type, an ultrasonic type, a capacitance type, an electric field measurement type, and a heat sensing type.

The thermal sensing method acquires the fingerprint image by moving the finger on the heat sensor. It can detect dry fingerprints, has a small sensor size, and is cheap. However, it is not convenient for users because it requires skill.

Both capacitive and electric field measurement methods are semiconductor type fingerprint recognition devices. Semiconductor type is advantageous in that it can measure dried fingerprints, but has poor durability against moisture and sensor is very expensive.

On the other hand, optical sensors are cheap, but sensors are not influenced by moisture and can obtain excellent fingerprint images. However, since only the appearance of the fingerprint is judged mainly, the fingerprint of the dummy having the shape of the fingerprint, And is recognized as an image.

The fingerprint recognition device is installed for security. Even if the fingerprint is recognized as it is, there is a problem that security is weakened.

Conventionally, there has been developed a device capable of detecting the forgery through a method of detecting the reflection of the skin or the color of the skin to judge whether or not the image has been falsified or using the surface plasmon effect. However, There was a limit in strengthening.

In recent years, light emitting diodes have been developed, and a length capable of intensively emitting only light beams of a desired wavelength range has been opened, so that it has become possible to utilize not only visible light of a specific wavelength band but also ultraviolet light or infrared light.

However, even in the case of using a light emitting diode, a technique for obtaining a fingerprint image more clearly by using a diode which mainly emits light of a wavelength range having a good scattering characteristic mainly in a visible light region is mainly developed, However, it is a reality that the development of the technology that can distinguish the fingerprints that are made is not supported.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fingerprint recognition device capable of accurately discriminating whether or not a fingerprint is a forged fingerprint by utilizing characteristics of light different for each wavelength.

SUMMARY OF THE INVENTION The present invention has been conceived to solve the problems described above, and it is an object of the present invention to provide a fingerprint recognition apparatus and a fingerprint recognition apparatus which utilize light of a specific wavelength band in an ultraviolet ray and an infrared ray region or a visible ray region, A fingerprint recognition device and a fingerprint recognition method capable of accurately recognizing only a fingerprint of a living body.

According to another aspect of the present invention, there is provided a fingerprint recognition apparatus capable of identifying authenticity of a fingerprint by acquiring not only a surface of a biometric fingerprint but also internal information of an internal structure of a living body having a fingerprint, The purpose is to provide.

In order to achieve the above-mentioned object, the present invention provides a method of manufacturing an image sensor, comprising the steps of: optically acquiring a shape of a fingerprint touched on a contact surface (20); And a step of irradiating light toward the fingerprint and obtaining bio-light information of the finger having the fingerprint in a state where the fingerprint is in contact with the contact surface (20), the method comprising the steps of: And determining that the acquired fingerprint is a biometric fingerprint when the oxygen saturation calculated from the first wavelength light absorption amount of the first wavelength and the light absorption amount of the second wavelength of blood is within a predetermined range.

The light of the first wavelength may be a wavelength of light in which hemoglobin (Hb) and oxygen hemoglobin (HbO ₂ ) have the same absorption coefficient.

At least one of the value of the first wavelength or the value of the second wavelength may be changed each time the fingerprint is recognized.

The light irradiated toward the fingerprint may include light of the first wavelength and light of the second wavelength.

The optical information of the first wavelength and the optical information of the second wavelength can be extracted from the acquired bio-light information of the finger to acquire the optical information of the first wavelength and the optical information of the second wavelength.

The present invention also provides a light source unit (30) including a base (32) provided with a light source; A contact surface 20 provided at a position irradiated with light irradiated from a light source provided on the base and contacting the fingerprint 10; A photometric unit 40 positioned adjacent to the base 32; And an optical information processing unit for processing optical information obtained through the light measuring unit 40 after the light irradiated from the light source passes through the contact surface 20. The optical information processing unit is configured to measure the first wavelength light absorption amount And determining whether the oxygen saturation calculated from the light absorption amount of the second wavelength of blood is within a predetermined range.

A first polarizing filter (51) disposed on a light path from the light source of the base to the contact surface (20); And a third polarizing filter (53) disposed on the optical path from the contact surface (20) to the photometry part (40), wherein the first polarizing direction of the first polarizing filter and the third polarizing filter The third direction, which is the polarization direction of the filter, may be perpendicular to each other.

And a second polarizing filter (52) disposed on a light path from the light source of the base to the contact surface (20), wherein a second direction of polarization of the second polarizing filter and a second direction of polarization of the third polarizing filter The third direction, which is the polarization direction, may be parallel to each other.

The base 32 may have an annular shape, and the photometric unit 40 may be located at an annular center of the base.

The base 32 is rotatable about an annular center.

The first polarizing filter 51 and the third polarizing filter 53 are rotatable about the center of the annular shape of the base 32.

The light source may include a light source that emits light of a first wavelength and a light source that emits light of a second wavelength.

The unit area of the photometric unit 40 may include a first photometric device that senses light of a first wavelength and a second photometric device that senses light of a second wavelength.

A first pass filter for passing only light of a first wavelength and a second pass filter for passing only light of a second wavelength may be provided in front of the light measuring element.

At least one of the value of the first wavelength or the value of the second wavelength may be changed each time the fingerprint is recognized.

The light source unit 30 is disposed on the oblique plane of the prism and the light emitted from the light source unit 30 passes through the oblique plane of the prism and is incident on the contact surface 20 And the light measuring unit 40 is arranged on a side of a short side of a trapezoid shape so as to receive light passing through a surface forming a short side of the prism.

The present invention also provides a light source unit (30) including a base (32) provided with a light source; A contact surface 20 provided at a position irradiated with light irradiated from a light source provided on the base and contacting the fingerprint 10; A photometric unit 40 positioned adjacent to the base 32; Having a split surface (56) disposed on the light path from the light source of the base to the contact surface (20) and on the light path leading from the contact surface (20) to the light measuring portion (40) A lit cube 55; And an optical information processing unit for processing optical information obtained through the light measuring unit 40 after the light irradiated from the light source passes through the contact surface 20. The optical information processing unit is configured to measure the first wavelength light absorption amount And determining whether the oxygen saturation calculated from the light absorption amount of the second wavelength of blood is within a predetermined range.

The installation surface of the light source unit 30 and the installation surface of the light metering unit 40 are not located on the surfaces of the beam splitter cube facing each other but on different surfaces with respect to the split surface 56 .

The contact surface 20 may be located on a surface of the beam splitter cube that faces the light measuring unit 40.

According to the present invention, not only the surface of the biometric fingerprint but also the internal information of the biometric information with the fingerprint can be obtained to determine authenticity of the fingerprint.

According to the present invention, not only an image can be obtained by irradiating light of a desired wavelength to a fingerprint, but also an image can be obtained by irradiating light polarized by a desired polarization direction, and a very uniform and accurate image can be obtained have.

The above and other objects, features and advantages of the present invention will be more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which: FIG.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view showing an image acquisition principle of a fingerprint recognition apparatus according to the present invention;
FIG. 2 is a side view of a fingerprint recognition device according to a first embodiment of the present invention,
Fig. 3 is a plan view of the fingerprint recognition device of Fig. 2,
FIG. 4 is a side view of a fingerprint recognition device according to a second embodiment of the present invention,
FIG. 5 is a plan view of the fingerprint recognition device of FIG. 4,
FIG. 6 is a view illustrating a structure of a fingerprint recognition device according to a third embodiment of the present invention,
FIG. 7 is a front view showing a first embodiment of the fingerprint recognition device of FIG. 6;
FIG. 8 is a front view showing a second embodiment of the fingerprint recognition device of FIG. 6;
FIG. 9 is a front view showing a third embodiment of the fingerprint recognition device of FIG. 6;
10 and 11 are views showing an embodiment of the photometric unit of the present invention,
12 is a view showing a depth through which ultraviolet rays penetrate the skin tissue,
13 is a graph showing a light absorption rate of blood and water by wavelength,
14 is a graph showing the presence of waves due to blood flow in the light information obtained by irradiating light to the finger end where the fingerprint is formed,
15 and 16 are side views of a fingerprint recognition device as a modification of the second embodiment according to the present invention, and Figs.
17 is an image showing blood vessel information of a finger photographed by the fingerprint recognition device of Figs. 15 and 16. Fig.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

It is to be understood that the present invention is not limited to the disclosed embodiments, but may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, It is provided to inform.

1 is a view showing an image acquisition principle of a fingerprint recognition apparatus according to the present invention. Generally, when a light is irradiated on the skin of a human body, a part of light is reflected on the surface, and a part of light is reflected after being transmitted to the inside of the skin.

This is also related to the polarization direction of the light. 1 (a), when light polarized at zero is irradiated to the skin, most of the light polarized at zero is similarly reflected at the skin surface. However, most of the light transmitted through the skin surface to the inside of the skin is absorbed and scattered, resulting in loss of polarization and scattering out of the skin. Most of the light transmitted through the surface of the skin is polarized at 90 degrees and reflected by the surface of the skin. It comes out.

Therefore, when the polarized light is irradiated to the skin, the reflected light or the scattered light having the same polarization direction as the irradiated polarization direction can be measured and observed to obtain information about the skin surface, and a 90-degree polarized reflected light Or scattered light, it is possible to acquire more information about the inside of the skin than the surface of the skin.

Since a general optical type fingerprint recognition device is a method of recognizing the appearance of a fingerprint, even if a dummy having the same appearance as the actual fingerprint is used, the same fingerprint is recognized. Of course, since optical fingerprint recognition devices do not recognize dry fingerprints, dry dummies may not be able to recognize fingerprints, but such moisture can be created in any amount. However, the fingerprint information input to the fingerprint recognition device includes not only the fingerprint shape of the surface, but also the shape of the tissue (e.g., blood vessel) inside the skin where the fingerprint is formed. It is very difficult to deceive the fingerprint recognition device such as making a fingerprint with a dummy if images can be obtained from the fingerprint image on the surface and the shape of the tissue inside the skin and compared with the stored information.

Hereinafter, an optical fingerprint recognition apparatus using this principle will be described.

[First Embodiment of Optical System of Fingerprint Recognition Device]

FIG. 2 is a side view of a fingerprint recognition device according to a first embodiment of the present invention, and FIG. 3 is a plan view of the fingerprint recognition device of FIG. That is, FIG. 3 is a view showing the fingerprint recognition device of FIG. 2 viewed from above.

2, the light source unit 30 and the light metering unit 40 are spaced apart from each other with respect to the contact surface 20 on which the fingerprint 10 contacts, and the light source of the light source unit can irradiate light toward the contact surface 20 The light measuring unit is provided in such a direction that light reflected or scattered from the contact surface 20 can reach the light measuring element of the light measuring unit.

Polarization filters 51 and 52 are provided on the path of the light irradiated from the light source of the light source unit and are reflected or scattered from the contact surface 20 in front of the light metering unit 40, A polarization filter 53 is provided on the path of the incoming light.

The polarizing direction of the first polarizing filter 51 is perpendicular to the polarizing direction of the third polarizing filter 53 and the polarizing direction of the second polarizing filter 52 is perpendicular to the polarizing direction of the third polarizing filter 53 It is parallel.

Therefore, the light is irradiated on the contact surface 20 through the second polarizing filter 52 as shown in FIG. 2 (a), then scattered or reflected at the contact surface, and reaches the photometric unit 40 via the third polarizing filter 53, The light mainly includes information on the skin surface, that is, the shape of the fingerprint as shown in Fig. 1 (a).

On the other hand, as shown in FIG. 2 (b), the light is irradiated to the contact surface 20 through the first polarizing filter 51 and then scattered or reflected at the contact surface, reaches the photometry part 40 via the third polarizing filter 53, As shown in Fig. 1 (b), the light mainly contains information about the skin surface, that is, the shape of the fingerprint.

Therefore, according to the first embodiment, information on the outline of the fingerprint 10 is obtained by irradiating light to the contact surface 20 as shown in FIG. 2A, It is possible to acquire information of the deep part of the fingerprint 10 by irradiating light as shown in the figure.

On the other hand, there is a difference in the wavelength range of the light required to obtain the information of the appearance of the fingerprint and the information of the deep part more clearly than the fingerprint. For example, the shorter the wavelength of light is, the lower the transmittance to the skin becomes. In the case of ultraviolet rays, most of the UVB wavelengths are absorbed from the epidermis and do not reach the dermal layer, but reach the dermal layer in the case of UVA wavelength (see FIG. 13).

Therefore, it is necessary to make a difference in the wavelength of light to be irradiated by the light source unit 30 according to the information inside the skin to be obtained. 3, the light source unit 30 includes an annular base 32, and a plurality of light sources 30-1, 30-2, 30-3, and 30-3 for emitting light having different wavelengths are formed on the annular base 32, 30-2, 30-3, ... 30-n. A plurality of light sources (two in the embodiment of the present invention) for irradiating light of the same wavelength are provided, and are provided radially with respect to the center of the annular shape. By arranging the light source radially with respect to the center of the annular shape, strictly speaking, with respect to the photometric unit, the influence of the difference in the shading direction of the fingerprint generated according to the position of the light source on the photographed image can be minimized.

These light sources may be composed of LEDs. The LED is very suitable as the light source of the fingerprint recognition device of the present invention in that the spectrum half width is narrow and the light of the peak wavelength range is intensively emitted.

On the other hand, the center of the annular base is provided with a light metering section 40, and polarizing filters 51, 52 and 53 are provided in front of the light source section 30 and the light metering section 40. The first polarizing filter 51 is provided with a plurality of (two in the embodiment of the present invention) the same number as the number of the light sources irradiating the light of the same wavelength, and this also applies to the second polarizing filter 52. Also, the plurality of first polarizing filters are provided radially with respect to the center of the annular shape, and this also applies to the second polarizing filter 52.

In order to obtain information on the fingerprint shape of the skin surface as shown in FIG. 1A, the first light source (for example, 30-1. At this time, the wavelength of the light emitted from the first light source 30-1 is a wavelength belonging to a wavelength band suitable for obtaining information on the surface of the skin. Therefore, the light measured by the photometric unit 40 is parallel polarized in the same direction in the wavelength range of the first light source, so that information on the skin surface can be obtained.

Next, as shown in FIG. 1 (b), in order to obtain information on the fingerprint shape of the deep part of the skin, as shown in FIG. 3 (b) or 3 (c) And the second light source 30-2 under the filter 51 irradiates light. At this time, the wavelength of the light emitted from the second light source 30-2 is a wavelength belonging to a wavelength band suitable for obtaining information of the deep portion of the skin. Therefore, the light measured by the photometry unit 40 is polarized in the direction of 90 degrees with respect to the wavelength of the second light source, so that information on the skin depth can be obtained.

In order to irradiate the light of the desired wavelength range through the desired polarizing filter, the annular light source portion 30 may be configured to rotate about the center of the annular shape. 3 (a), when the light source unit 30 is rotated one turn in the direction of arrow b, the light source 30-2 is positioned under the desired polarization filter 51 as shown in FIG. 3 (b) .

Further, in order to irradiate the light of the desired wavelength band to pass through the desired polarizing filter, the polarizing filters 51, 52 and 53 may be configured to rotate integrally with respect to the center of the annular shape. 3 (a), when the polarization filters 51, 52 and 53 are rotated one turn in the direction of the arrow c, the light source 30-2 as shown in FIG. 3 (c) 51).

Of course, it is also possible to irradiate a non-polarized light source in such a fingerprint recognition device. For example, when the light is emitted from the second light source 30-2 in FIG. 3A, it is possible to irradiate the unpolarized light.

According to the above-described fingerprint recognition apparatus, it is possible not only to acquire an image by irradiating light of a desired wavelength to the fingerprint 10, but also to acquire an image by irradiating the light polarized in a desired direction.

[Second Embodiment of Optical System of Fingerprint Recognition Device]

FIG. 4 is a side view of a fingerprint recognition device according to a second embodiment of the present invention, and FIG. 5 is a plan view of the fingerprint recognition device of FIG. That is, FIG. 5 is a view showing the fingerprint recognition device of FIG. 4 viewed from above.

The second embodiment of FIG. 4 is different from the first embodiment of FIG. 2 in that a trapezoidal prism is formed so that the contact surface 20 is located on a side of a long side of a trapezoidal prism, The light emitted from the light source unit 30 passes through the oblique plane of the prism and is irradiated to the contact surface 20, and the photometric unit 40 is disposed on a plane forming a trapezoidal short side There is a difference in that light that passes through a surface of a short side of the prism is received.

The polarization filters 51, 52, and 53 may be disposed between the prism and the light source, and between the prism and the photometric unit, and may be attached on the surface of the prism.

The photometric unit 40 may be disposed under the third polarizing filter 53 and may be in close contact with the third polarizing filter.

The light source unit 30 is positioned below the first and second polarizing filters 51 and 52 and may be in the form of being in close contact with the polarizing filter. The light source unit 30 may not be in close contact with the first polarizing filter 51 and the second polarizing filter 52 when it is necessary to move the plurality of light sources of the light source unit 30 as necessary.

Referring to FIG. 5, the light source unit of the fingerprint recognition apparatus of the second embodiment may have a plurality of light sources 30-1, 30-2, and 30-3 arranged in a line on a linear base 32. FIG. The plurality of light sources may be light emitting diodes (LEDs) that emit light having different peak wavelengths. Therefore, according to the present invention, the image of the fingerprint and the in-vivo information can be obtained with the light of the desired wavelength band by emitting light from the desired light source as necessary.

For example, in order to obtain information on the fingerprint shape of the skin surface as shown in FIG. 1A, the first light source 52 under the second polarizing filter 52, as shown in FIG. 5A, (Light source in the upper part in the figure). At this time, the wavelength of the light emitted from the first light source 30-1 is a wavelength belonging to a wavelength band suitable for obtaining information on the surface of the skin. Therefore, the light measured by the photometric unit 40 is parallel polarized in the same direction in the wavelength range of the first light source, so that information on the skin surface can be obtained.

Next, as shown in FIG. 1 (b), in order to obtain information about the fingerprint shape of the deep part of the skin, as shown in FIG. 5 (b) And light is irradiated from the light source 30-3 (light source at the lower part in the drawing). At this time, the wavelength of the light emitted from the third light source 30-3 is a wavelength belonging to a wavelength band suitable for obtaining information of the deep part of the skin. Therefore, the light measured by the photometric unit 40 is polarized in the direction of 90 degrees with respect to the third light source, so information on the skin depth can be obtained.

At this time, the base 32 is configured to be movable left and right in the drawing. Therefore, it is possible to cause the desired light source to be positioned and emit light. Of course, it is also possible to construct the base fixedly if all of the light sources are densely arranged and all the light sources are located within the predetermined range, even if the base is not moved.

According to the above-described fingerprint recognition apparatus, it is possible not only to acquire an image by irradiating light of a desired wavelength to the fingerprint 10, but also to acquire an image by irradiating light polarized by a desired polarization direction.

[Third Embodiment of Optical System of Fingerprint Recognition Device]

6 is a front view showing a first embodiment of the fingerprint recognition device of Fig. 6, Fig. 8 is a front view of the fingerprint recognition device of Fig. 6 is a front view showing a second embodiment of the fingerprint recognition device in Fig. 6, and Fig. 9 is a front view showing a third embodiment of the fingerprint recognition device in Fig.

Referring to FIG. 6, the fingerprint recognition apparatus of the present invention includes a beam splitter cube 55. In the beam splitter cube 55, a split plane 56 is formed between two mutually parallel but most distant sides as shown. The split surface 56 reflects the polarized light in the direction parallel to the split surface 56 and transmits the polarized light in the direction intersecting the split surface 56. [

In this beam splitter cube 55, the light source 30 is provided on one side of the beam splitter cube 55 facing the split plane 56 as shown in Fig. 6, and the same split plane 56 is observed And forms the contact surface 20 of the fingerprint 10 (solid line portion in Fig. 6) on the other surface of the beam splitter cube.

Next, the photometric unit 40 is provided on one side of the beam splitter cube 55 facing the back side of the split plane 56. That is, the installation surface of the light source unit 30 and the installation surface of the light metering unit 40 are installed at positions where they face different surfaces of the split surface 56. The mounting surface of the light source unit 30 and the mounting surface of the light metering unit 40 are not provided on the surfaces of the beam splitter cube facing each other. This is to prevent the light irradiated from the light source from being irradiated directly into the light metering section 40 without going through the contact surface 20 of the fingerprint 10.

And the contact surface 20 is located on a face of the beam splitter cube facing the photodetection unit 40. [

6, when the light is irradiated toward the split surface 56 in the light source unit 30, the light polarized in the first direction is irradiated onto the fingerprint 10. The light reflected or scattered through the fingerprint again has both the first direction component and the second direction component, which again reaches the split face 56 as shown, Only the light polarized in the direction (-) passes through the split surface 56 and reaches the photometric unit 40.

Therefore, when the fingerprint recognition device is configured as described above, the light emitted through the fingerprint and the light emitted from the fingerprint are polarized in the direction of 90 degrees from each other, so that information of the deep part of the fingerprint can be obtained.

Of course, in FIG. 6, the fingerprint 10 may be positioned at the dotted line portion. In this case as well, the light irradiated to the fingerprint and the light emitted through the fingerprint are polarized in the direction of 90 degrees from each other, so that the information of the deep part of the fingerprint can be acquired.

When the beam splitter cube is used, the direction of the light irradiated to the fingerprint is the front direction with respect to the fingerprint, and the direction of the light irradiated to the photometry unit 40 after passing through the fingerprint is also the front direction with respect to the fingerprint. It can be photographed by a light source illuminating from the front exactly, so that a shadowless image can be obtained. Further, since the incidence angle and the reflection angle do not exist and the close-up photographing can be performed, it is very suitable for constituting the fingerprint recognition device.

As shown in FIG. 7, the light source unit 30 includes a plurality of light sources 30-1, 30-2, 30-3, ..., 30-n that emit light of different wavelengths. These light sources are provided on the inner surface of the annular base 32. The other part of the beam splitter cube 55 is covered with the light absorbing film 58 except for the part where the light is incident, so that other light is incident on the beam splitter cube 55, To prevent re-entry into the splitter cube.

The annular base 32 is rotatable about a beam splitter cube 55. Therefore, after the light is irradiated to the first light source 30-1, it is possible to rotate in the direction of the arrow and irradiate the light to the second light source 30-2 again.

Therefore, according to the fingerprint recognition apparatus shown in Fig. 7, it is possible not only to acquire an image by irradiating light of a desired wavelength to the fingerprint 10, but also to acquire images with the polarization direction of light emitted through the fingerprint and the light passing through the fingerprint perpendicular to each other The image of the fingerprint can be obtained.

On the other hand, it is also possible to construct a fingerprint recognition device as shown in FIG. 8, the light source unit 30 includes a base 32 having a circular shape as shown in the figure, and the plurality of light sources 30-1, 30-2, 30-3, 30-4 are provided on the outer surface of the base 32 so as to project light toward the center of the circular shape. The center of the base 32 of the light source unit 30 is present outside the beam splitter cube 55, which is different.

The circular base 32 is also rotatable about its center. Therefore, after the light is irradiated to the first light source 30-1, it is possible to rotate in the direction of the arrow and irradiate the light to the second light source 30-2 again.

Therefore, according to the fingerprint recognition apparatus shown in FIG. 8, light having a desired wavelength can be irradiated on the fingerprint 10 to acquire an image. In addition, since the polarization direction of light emitted through the fingerprint is perpendicular to the direction of polarization The image of the fingerprint can be obtained.

On the other hand, it is also possible to construct a fingerprint recognition device as shown in FIG. 9, the fingerprint recognition apparatus of FIG. 9 includes a base 32 having a linear shape of the light source unit 30, a plurality of light sources 30-1, 30-2, and 30-3, The beam splitter cube 55 is provided on the side facing the beam splitter cube 55 and irradiated with light toward the beam splitter cube 55. The base 32 of this light source section 30 is located outside the beam splitter cube 55.

The straight base 32 is reciprocatable in its longitudinal direction. Therefore, after the first light source 30-1 is irradiated with light, it is possible to move in the direction of the arrow and irradiate the light to another light source, for example, the illustrated third light source 30-3. Of course, it is also possible to construct the base fixedly if all of the light sources are densely arranged and all the light sources are located within the predetermined range, even if the base is not moved.

Therefore, according to the fingerprint recognition apparatus shown in FIG. 9, light having a desired wavelength can be irradiated to the fingerprint 10 to acquire an image, and also, when the light radiated to the fingerprint and the light passing through the fingerprint are perpendicular to each other The image of the fingerprint can be obtained.

[Configuration of the photometric unit of the fingerprint recognition device]

FIGS. 10 and 11 are views showing an embodiment of the photometric unit of the present invention. FIG.

A conventional photometry unit includes a pass filter for each wavelength region in front of a photometry element (such as a CCD or a CMOS) to remove the light in the infrared or ultraviolet region so that only the visible light reaches the photometry element, , And light-sensing elements for generating an electrical signal corresponding to the wavelength of the blue component are arranged in a matrix form to acquire an image of light.

On the other hand, as shown in Fig. 10, the photometric unit 40 according to the present invention includes a plurality of photometric devices 42-1 (see Fig. 10) capable of measuring light of a plurality of small-band wavelengths within a wavelength band necessary for fingerprint measurement and photographing, , 42-2, ..., 42-n.

Also, as shown in FIG. 11, a pass filter 45 may be provided in front of the photometric device so as to pass only light of the plurality of small-band wavelengths. The pass filter 45 has a plurality of pass filters 45-1, 45-2, ... 45-n for passing only light of one small-band wavelength as shown, A method of putting it in front of the photometric element can be used. Alternatively, a plurality of filters may be used to block only light of a specific wavelength band, and the remaining filters may be overlapped except for a filter that blocks light of a corresponding wavelength band when passing only light of a desired wavelength band.

If the wavelength range of the pass filter 45 is narrowed (set) and the measurement wavelength range of the photometric devices is narrowed and diversified according to the use purpose of the photometric device, only the optical information of the desired wavelength range is acquired, Can be obtained.

At least one of the plurality of wavelength sub-bands may be in an ultraviolet wavelength region or an infrared wavelength region for grasping the depth information of the fingerprint.

Since the light source that provides the wide-band wavelength can acquire information of various wavelengths, it is possible to acquire information of various wavelength ranges without the plurality of light sources described in the first to third embodiments, Can be obtained.

[Fingerprint Recognition Method and Apparatus Utilizing Light Absorption Rate and Skin Tissue Permeability Dependent on Blood Wavelength]

FIG. 12 is a graph showing the depth of penetration of ultraviolet rays to skin tissue, and FIG. 13 is a graph showing the light absorption rate of blood and water by wavelength.

There is a difference in the penetration depth of the light by the wavelength band. Generally, the ability of the skin to penetrate the skin becomes larger as the wavelength goes to the longer infrared region, and the light penetrating ability of the light becomes lower as the wavelength becomes shorter.

On the other hand, as shown in FIG. 12, the capillary blood vessels are mainly located in the dermis in the human tissue. When the skin is pressed, the dermis is whitened and blood in the blood vessel is evacuated. In other words, the blood in the blood vessels in the dermis of the pressed area is drained away.

13, the light absorption rate of blood is shown for each wavelength. As can be seen, the light absorption rate of the blood is highest in the ultraviolet region, and gradually decreases toward the infrared region through the visible light region. On the other hand, the light absorption rate of each wavelength of water decreases gradually from the UVC region to the UVA region, and gradually increases from the near ultraviolet region to the infrared region. Referring to FIG. 13, the wavelength band in which the difference between the light absorption rate of blood and the light absorption rate of water is large may be an ultraviolet region band and a visible light region band, particularly 280 nm to 620 nm.

Therefore, when light having a peak wavelength of 280 nm to 620 nm is irradiated to a tissue in which blood mainly exists, a difference in optical information measured depending on the presence or absence of blood can be remarkably exhibited.

Referring again to FIG. 12, it is difficult to obtain reflected light or scattered light that can determine whether blood exists in a blood vessel because UVB out of the light irradiated to the skin can penetrate only to the epidermis. On the other hand, since UVA is absorbed or scattered after penetrating into the dermis mainly distributed in capillary blood vessels, when UVA light absorbed or scattered after penetration into the dermis is analyzed to analyze the information, blood is present in the capillaries of the dermis Can be determined.

Therefore, if the information of the scattered light is analyzed after irradiating the skin with the light of the UVA wavelength band (320 nm to 400 nm), which is largely different from the optical information depending on whether blood is present in the capillary present in the dermis, Can be easily identified. In other words, the method of recognizing the fingerprint by applying this principle can finally determine whether the object having the shape of the fingerprint is the living body, so that the authenticity of the fingerprint can be judged.

Therefore, in a state in which the fingerprint lightly contacts the contact surface 20, light of a predetermined wavelength is irradiated toward the fingerprint to obtain biometric information of the finger where the fingerprint is formed, and the contact surface 20 is pressed firmly The blood of the blood vessel located in the blood vessel is pushed out, the light of a predetermined wavelength is irradiated toward the fingerprint to obtain biometric information of the finger having the fingerprint, and then the two pieces of optical information are compared with each other, If the difference in information can be confirmed, it is possible to determine that the object on which the fingerprint is formed is a living body. Of course, if the wavelength of the light irradiated to the living body is the same before the fingerprint is pressed and the fingerprint is pressed to acquire the optical information, the algorithm for determining the living body can be constructed more simply. However, the wavelength of the light irradiated to the living body must not necessarily be the same.

As a result, if the shape of the fingerprint is optically acquired and then the living body determination step is performed, the shape of the optically acquired fingerprint can be regarded as true.

On the other hand, as described above, when the direction of polarization of the light irradiated to the living body and the direction of polarization of the light after being irradiated to the living body are perpendicular to each other, taking the fact that photometry information includes more information of the deep- It is more advantageous to obtain more definite optical information by constructing the polarization direction of the light irradiated toward the fingerprint after applying pressure to the fingerprint and the polarization direction of the light to be photographed perpendicular to each other.

In addition, even if the light irradiated toward the fingerprint is a white light of a broad band before the fingerprint is pressed and the fingerprint is pressed as above, information corresponding to the ultraviolet region of 320 nm to 400 nm is extracted from the photometry information It is also possible to pass the above-mentioned step of discriminating the living body.

In the case where the wavelength band of the light suitable for optically obtaining the shape of the fingerprint and the wavelength band of the light suitable for grasping the information on the blood presence or absence in the capillary vessel of the living body are configured differently, .

A fingerprint recognition apparatus to which the above-described fingerprint recognition method is applied can be implemented as follows.

A light source unit 30 including a base 32 provided with a light source and a light source unit 30 provided at a position irradiated with light from a light source provided on the base, A contact surface 20 which is in contact with the base 32 and a light measuring unit 40 located adjacent to the base 32.

At this time, the light source provided on the base includes a light source for irradiating light of a wavelength band optically suitable for acquiring the shape of the fingerprint, and a light source for irradiating light of a wavelength band suitable for grasping information on the presence or absence of blood in the capillary vessel of the living body .

In addition, the present invention includes an optical information processing unit for processing optical information obtained through the light-measuring unit 40 after the light emitted from the light source passes through the contact surface 20, The light information obtained through the photometry unit 40 in a state in which the fingerprint is in contact with the finger and the blood located inside the finger where the fingerprint is formed by pressing the contact surface 20 are pushed out, And the obtained optical information is compared with each other.

When the difference of the optical information is equal to or greater than the predetermined value through such processing, the finger having the fingerprint can be determined as a living body.

Such a fingerprint recognition apparatus may further include an instruction unit for instructing the person who has made contact with the fingerprint 10 on the contact surface 20 to press the fingerprint 10 firmly for the convenience of the user. That is, the fingerprint recognition device instructs the fingerprint to be pressed hard when the fingerprint information is obtained before pressing the fingerprint firmly, and then obtains the information of the fingerprint by irradiating the fingerprint again.

Next, a first polarizing filter 51 is disposed on the light path from the light source for irradiating the light of the wavelength band required for grasping the deep portion information of the living body on which the fingerprint is formed to the contact surface 20, A third polarizing filter 53 disposed on the optical path leading to the photometering unit 40 is disposed so that the polarization direction of the first polarizing filter and the polarization direction of the third polarizing filter are perpendicular to each other. The second polarizing filter 52 is disposed on the optical path from the light source for irradiating light of the wavelength band necessary for grasping the shape information of the fingerprint to the contact surface 20, So that the polarization directions of the polarizing filters are parallel to each other. 3 (a) to 3 (b), the position of the light source may be changed as shown in FIG. 3 (a) to (c) You can change the position and implement it like this.

It is, of course, also possible to operate the apparatus through the same operation as in FIG. 3 even when the wavelength band necessary for grasping the shape information of the fingerprint and the wavelength band necessary for grasping the deep information of the living body in which the fingerprint is formed are made equal to each other.

If a light measuring element for detecting light having a wavelength of 320 nm to 400 nm is provided in the unit area of the photometry part 40, it is not necessary to configure the light source as a light source that emits light having a wavelength of 320 to 400 nm, This also applies to the case where a pass filter 45 for passing only light having a wavelength of 320 nm to 400 nm is provided in front of the light measuring element.

The fingerprint recognition device of this type may be constructed by utilizing a prism having a trapezoidal shape as in the second embodiment of the optical system, or may be constructed using the beam splitter cube 55 as in the third embodiment of the optical system And the present invention does not exclude these matters.

Since the above-described optical system can implement a plurality of light sources having different wavelengths and a polarizing filter having different directions in one apparatus, the light absorption rate of each wavelength of blood and the penetration depth of skin tissue per light wavelength It is possible to combine the principle of fingerprint recognition and other optical fingerprint recognition principles described in the present invention. The greater the number of such combinations, the lower the possibility of using false fingerprints.

[Fingerprint Recognition Method and Apparatus for Detecting Waves by Blood Flow Macros]

14 is a graph showing the presence of waves due to blood flow in the light information obtained by irradiating light to the finger end where the fingerprint is formed.

As shown in Fig. 14, there are blood vessels leading to arterial-capillary-vein in human tissues, and in particular, arterial blood has pulsation of the same pulse as that of the heart. Therefore, the amount of blood is increased or decreased in a certain portion of the body tissue, such as the fingertip portion shown in FIG. 14, the same as the heart rate. In view of such characteristics of the living body, the present invention is characterized in that the finger having the fingerprint is recognized as a living body by sensing the fluctuation of the blood flow amount at the finger tip portion where the fingerprint is formed when the fingerprint is recognized.

The present invention further provides a method for detecting hemoglobin in a blood vessel by taking into consideration that oxygen hemoglobin changes into hemoglobin when arterial blood passes through capillaries and venous blood and oxygen hemoglobin and hemoglobin have different absorption ratios with respect to light of a specific wavelength band, Is irradiated to the fingertip, and then the light information from the finger is analyzed to further confirm the authenticity of the living body. For example, when light having a wavelength of 480 nm is irradiated to the fingertip portion, as shown in FIG. 13, the light absorptance of the arterial blood is higher than the light absorption rate of the venous blood, so that the overall light absorption rate drops sharply while the arterial blood goes to the vein. In addition, when the light of 690 nm wavelength is irradiated to the fingertip portion, the overall light absorption rate increases sharply while the blood of the artery goes into the vein. Therefore, if it is possible to detect the fluctuation of the light absorption rate in the optical information by the period corresponding to the human pulse, the living body can be judged more accurately.

In addition, the difference in intensity of the photodetector signal caused by the difference in the light absorption rate of the arterial blood and the venous blood to the corresponding wavelength of the optical information, in theory, The procedure for confirming whether or not the light absorption rate of the venous blood is equal to or greater than the difference in the light absorption rate of the venous blood is further performed.

In addition, since there is a difference between the tissue and the internal constituents of the fingertip portion of each person, even when optical information of the same wavelength is used, the difference in intensity of signals of the photodetector caused by difference in the light absorption rate of arterial blood and venous blood for each person is different . Therefore, if the intensity difference of the signal of the photodetector generated by the difference between the fingerprint information of the person and the light absorptivity of the arterial blood and the venous blood of the person having the fingerprint is data for each wavelength band, unique blood flow pulse wave data and fingerprint are generated for each individual .

Therefore, fingerprint authentication using this personal fingerprint and pulse wave data can greatly enhance security.

This makes it more difficult to make the fingerprint fake. For example, it is possible to implement a periodic fluctuation in the light absorption rate by putting a specific liquid into and out of a dummy in which a fingerprint is formed in a period corresponding to a human pulse rate. However, as described above, It is very difficult to artificially match.

Therefore, it is possible to confirm the above-described pulse wave information by irradiating the finger with light having a different absorption rate of hemoglobin (Hb) and oxygen hemoglobin (HbO ₂ ) when acquiring biometric information, and acquiring optical information .

In addition, in the optical information obtained after irradiating light having a wide wavelength (for example, white light) to a finger, optical information of a wavelength band having different absorption ratios of hemoglobin (Hb) and oxygen hemoglobin (HbO ₂ ) Can be confirmed.

In addition, since the selection of such a wavelength can be variously selected within a wavelength range in which hemoglobin (Hb) and oxygen hemoglobin (HbO ₂ ) have different absorption ratios and the light absorption rate of blood is already known for each wavelength, By irradiating light of different wavelengths within a possible wavelength range to measure pulse waves, the security function can be further enhanced.

A fingerprint recognition apparatus to which the above-described fingerprint recognition method is applied can be implemented as follows.

A light source unit 30 including a base 32 provided with a light source and a light source unit provided on a position where light emitted from a light source provided on the base is irradiated, A contact surface 20 which is in contact with the base 32 and a photometric unit 40 which is located adjacent to the base 32.

In this case, the light source provided in the base may include a light source for irradiating light of a wavelength band optically suitable for acquiring the shape of the fingerprint, and a light source for irradiating light of a wavelength band having a substantial absorption rate to blood. In addition, the light of the above-mentioned wavelength band having a considerable absorption rate to blood may be light of a wavelength band having different absorption rates for hemoglobin (Hb) and oxygen hemoglobin (HbO ₂ ). The wavelengths of the light for measurement of fingerprint shape and the light for pulse wave measurement may be the same or different. When the wavelengths are different from each other, a plurality of light sources emitting light of different wavelengths may be provided. When these wavelengths are different from each other, it is also possible to measure only the light of the corresponding wavelength in the photometry part, or to extract the optical information corresponding to the wavelength from the measured light information.

In addition, the present invention includes an optical information processing unit for processing optical information obtained through the light-measuring unit 40 after the light irradiated for a predetermined time passes through the contact surface 20 of the light source, When a pulse corresponding to a pulse of a living body is detected for a predetermined time, the finger having the fingerprint is determined to be a living body.

Particularly, when the light of the wavelength band having a significant absorption rate to blood is a light of a wavelength band having different absorption rates with respect to hemoglobin (Hb) and oxygen hemoglobin (HbO ₂ ), the difference in magnitude of the wave is not less than a predetermined value The finger can be judged to be a living body.

Next, the first polarizing filter 51 is disposed on the light path from the light source for irradiating the light of the wavelength band necessary for grasping the in vivo internal blood pressure information of the finger with the fingerprint to the contact surface 20, and the contact surface 20 And a third polarizing filter 53 disposed on the optical path from the first polarizing filter to the photometering unit 40 so that the polarization direction of the first polarizing filter and the polarization direction of the third polarizing filter are perpendicular to each other. The second polarizing filter 52 is disposed on the optical path from the light source for irradiating light of the wavelength band necessary for grasping the shape information of the fingerprint to the contact surface 20, So that the polarization directions of the polarizing filters are parallel to each other. 3 (a) to 3 (b), the position of the light source may be changed as shown in FIG. 3 (a) to (c) You can change the position and implement it like this.

It is, of course, also possible to operate the apparatus through the same operation as in Fig. 3 even when the wavelength band necessary for grasping the shape information of the fingerprint and the wavelength band necessary for grasping the blood vessel information inside the living body in which the fingerprint is formed are made equal to each other.

If the light measuring unit is provided with a light measuring element for detecting light of a wavelength band having different absorption ratios for hemoglobin (Hb) and oxygen hemoglobin (HbO ₂ ) in the unit area of the photometering unit 40, It is not necessary to constitute a light source which emits light, and even if it is provided with a pass filter 45 passing only light of a wavelength band having different absorption ratios for hemoglobin (Hb) and oxygen hemoglobin (HbO ₂ ) It is the same.

The fingerprint recognition apparatus may be constructed using a prism having a trapezoidal shape as in the second embodiment of the optical system, or may be constructed using the beam splitter cube 55 as in the third embodiment of the optical system Of course, the present invention does not exclude these matters.

Considering that the light irradiated to the finger is transmitted when the light of the wavelength band having different absorption rates for hemoglobin (Hb) and oxygen hemoglobin (HbO ₂ ) is in the infrared region, the second photometry May be positioned on the opposite side of the light source section 30 with reference to the contact surface 20 (see FIG. 16). Alternatively, it is also possible to position the second light source section on the opposite side of the photometric section 40 with respect to the contact surface 20 (see Fig. 15).

Since the above-described optical system can implement a plurality of light sources having different wavelengths and a polarization filter having different directions in one apparatus, the principle of fingerprint recognition that detects the wave caused by the blood flow pulse described above and the other optical fingerprint It is possible to implement it by combining the recognition principle. The greater the number of such combinations, the lower the possibility of using false fingerprints.

[Method and Apparatus for Fingerprint Recognition for Detecting Light Absorption of Blood According to Oxygen Saturation]

Referring to FIG. 13, blood has different light absorption degrees with respect to lights of different wavelengths. There is also a difference in light absorption between oxygen hemoglobin (HbO ₂ ) and hemoglobin (Hb) for light of the same wavelength. As shown in Fig. 13, the light absorbance is already known by wavelength and hemoglobin type. Here, light absorption of oxygen hemoglobin (HbO ₂ ) with respect to light of the first wavelength (a) can be expressed as εHbO _{2 a} , and light absorption of hemoglobin (Hb) can be expressed as εHb _a . The unit of ε is cm ^-1 / (moles / liter).

Next, geotinde more than the oxygen-hemoglobin (HbO ₂₎ The hemoglobin (Hb) in blood lower than the oxygen-hemoglobin (HbO ₂₎ The hemoglobin (Hb) of the will have a high oxygen saturation, contrast, blood with low oxygen saturation, at a moment The oxygen saturation of the photographed finger is the same. Here, the number of moles of oxygen hemoglobin is [HbO ₂ ], and the number of moles of hemoglobin is [Hb].

The light absorption amount of blood with respect to light can be confirmed by acquiring optical information that has been emitted through the finger in the light irradiated toward the fingerprint. For example, as the intensity of the acquired optical information increases, the amount of absorbed light of the blood is smaller and the absorbed amount of blood (A) of the blood becomes higher as the intensity of the obtained optical information becomes weaker.

The light absorption amount for the light of the first wavelength (a) can be expressed as follows.

_{A a = (εHbO 2a [HbO} 2] + εHb a [Hb]) L ... ( Equation 1)

Where L is the length of light passing through the area of blood.

On the other hand, the light absorption amount for the second wavelength b different from the first wavelength can also be expressed as follows.

A _b = (竜 HbO _2b [HbO ₂ ] + 竜 Hb _b [Hb]) L (2)

And In the above formula 1 and formula 2 A _a, A _b is a value measured through the photometry, εHbO _2a, εHb _a value of εHbO _2b, εHb _b is the known constant value in accordance with a first wavelength and a second wavelength value, L is the same in both equations. The values of [HbO ₂ ] and [Hb] are unknown, but since [HbO ₂ ] and [Hb] are the same in both equations, the above two equations are the simultaneous equations for [HbO ₂ ] and [Hb]. Therefore, the values of [HbO ₂ ] and [Hb] can be calculated based on the above equation. The oxygen saturation can be calculated from the values of [HbO ₂ ] and [Hb].

That is, the oxygen saturation HbO ₂ SAT is as follows.

_{HbO 2 SAT = {(A a} / A b) εHb b -εHb a} / {(A a / A b) (εHb b -εHbO 2b) + (εHbO 2a -εHb a)}

The oxygen saturation of the body is within that range, and the fingertip formed with the fingerprint also has a constant oxygen saturation.

Therefore, if the oxygen saturation calculated based on the light of the two wavelengths is included in the range of oxygen saturation that the fingertip portion of the living body can have, it can be confirmed that the object in which the fingerprint is formed is a living body.

On the other hand, in order to simplify such an algorithm, light of a third wavelength (c) different from the first wavelength may be used. The light of the third wavelength has the same εHbO _2c and εHb _c . Therefore, when the first wavelength and the third wavelength are irradiated, the oxygen saturation is more simply calculated as follows.

HbO ₂ SAT = {(A _a / A _c ) 竜 Hb _{c -}竜 Hb _a } / (竜 HbO _{2a -}竜 Hb _a )

Another advantage of this method is that by changing the wavelength of the light to be irradiated to calculate the oxygen saturation each time the fingerprint is recognized, it becomes more difficult or impossible to make the dummy for deceiving the fingerprint recognition device.

The light having the wavelength for measuring the oxygen saturation as described above may be irradiated by the light source, the light receiving unit may receive only the light of the corresponding wavelength, or may be extracted from the light information measured by the photometry unit.

A fingerprint recognition apparatus to which the above-described fingerprint recognition method is applied can be implemented as follows.

A light source unit 30 including a base 32 provided with a light source and a light source unit provided on a position where light emitted from a light source provided on the base is irradiated, A contact surface 20 which is in contact with the base 32 and a photometric unit 40 which is located adjacent to the base 32.

The light source provided at the base may include a light source for irradiating light of a wavelength optically suitable for acquiring the shape of the fingerprint and a light source for irradiating light of a plurality of different wavelengths suitable for calculating oxygen saturation of blood have. Either of the light optically suitable for acquiring the shape of the fingerprint and the light suitable for calculating the oxygen saturation of the blood may be the same.

In addition, the present invention includes an optical information processing unit for processing optical information obtained through the light measuring unit 40 after the light irradiated from the light source passes through the contact surface 20, and the optical information processing unit includes a first It is determined whether or not the oxygen saturation calculated from the wavelength light absorption amount and the light absorption amount of the second wavelength of blood is within a predetermined range.

Next, the first polarizing filter 51 is disposed on the light path from the light source for irradiating the light of the wavelength band necessary for grasping the oxygen saturation of the finger having the fingerprint formed thereon to the contact surface 20, A third polarizing filter 53 disposed on the optical path leading to the photometering unit 40 is disposed so that the polarization direction of the first polarizing filter and the polarization direction of the third polarizing filter are perpendicular to each other. The second polarizing filter 52 is disposed on the optical path from the light source for irradiating light of the wavelength band necessary for grasping the shape information of the fingerprint to the contact surface 20, So that the polarization directions of the polarizing filters are parallel to each other. 3 (a) to 3 (b), the position of the light source may be changed as shown in FIG. 3 (a) to (c) You can change the position and implement it like this.

Of course, even if the wavelength band necessary for grasping the shape information of the fingerprint and the wavelength band necessary for grasping the oxygen saturation information of the blood inside the living body in which the fingerprint is formed are the same, it is possible to operate the apparatus through the same operation as in Fig.

On the other hand, if a photometric device for sensing light of a wavelength band necessary for grasping information of blood oxygen saturation in a living body in which fingerprints are formed in the unit area of the photometric unit 40 is provided, the light source necessarily emits only light of the corresponding wavelength band It is not necessary to constitute a light source. This also applies to a case in which a pass filter 45 for passing only the light of the wavelength band required for grasping the oxygen saturation information of the blood inside the living body in which the fingerprint is formed in front of the photometric element is provided.

The fingerprint recognition apparatus may be constructed using a prism having a trapezoidal shape as in the second embodiment of the optical system, or may be constructed using the beam splitter cube 55 as in the third embodiment of the optical system Of course, the present invention does not exclude these matters.

When a light of a wavelength band necessary for grasping blood oxygen saturation information of the inside of a living body in which a fingerprint is formed is transmitted in the infrared region, a second photometric unit for measuring the light, It may be positioned on the opposite side of the light source section 30 with reference to the contact surface 20 (see FIG. 16). Alternatively, it is also possible to position the second light source section on the opposite side of the photometric section 40 with respect to the contact surface 20 (see Fig. 15).

Since the optical system described above can implement a plurality of light sources having different wavelengths and a polarizing filter having different directions in one apparatus, the principle of fingerprint recognition that detects the oxygen saturation of the blood described above and the other optical fingerprint recognition It is possible to implement them in combination. The greater the number of such combinations, the lower the possibility of using false fingerprints.

[Fingerprint recognition method and apparatus for detecting blood vessel information]

The longer the wavelength of light is, the greater its ability to penetrate the body. The near-infrared wavelength, in particular, has good permeability to the skin. On the other hand, as shown in Fig. 13, in the near infrared region, the light absorption of blood is larger than that of water.

When the finger having the fingerprint is irradiated with the light having the wavelength absorbed light different from that of the water while having good ability to transmit the body, the shape of the blood vessel can be imaged.

The fingerprint recognition device using the fingerprint recognition principle can be implemented as follows.

15 and 16 are side views of a fingerprint recognition device as a modification of the second embodiment according to the present invention. Referring to FIG. 15 and FIG. 16, a second light source 39 may be additionally installed at the opposite side of the first light source 30 with respect to the contact surface 20 as shown in FIG. 15 .

In the structure shown in Fig. 15, the second light source unit 39 irradiates infrared or near-infrared light with a finger toward a fingerprint formed thereon, and the infrared light or near-infrared light having passed through the finger is acquired by the photometry unit 40.

The first light source unit 30 also emits light toward the finger with the fingerprint and acquires the light scattered or reflected by the fingerprint 10 of the finger in the photometry unit 40. [

Here, the photometric unit 40 includes a second photometric device for sensing the light of the infrared or near infrared rays emitted from the second light source unit 39. Of course, the photometric unit 40 further includes a first photometric element that senses the light of the wavelength irradiated by the first light source unit 30.

And a second pass filter for passing only the light of the wavelength band irradiated by the second light source unit and passing only the light of the wavelength band irradiated by the first light source unit, The first pass filter may be provided to receive the light from the first light source unit and the second pass filter to receive the light from the second light source unit.

The optical information processing section implements the blood vessel shape inside the living body from the optical information of the infrared or near infrared ray wavelength acquired by the photometry section as shown in FIG. 17, and implements the shape of the fingerprint image. Then, the optical information processing unit confirms the identity using both the image of the blood vessel shape and the image of the fingerprint shape. That is, in the fingerprint identification device, in the identification process for identifying a person having previously registered fingerprint and blood vessel information, it is checked whether the previously registered fingerprint and the blood vessel shape information match the recognized fingerprint and the vessel shape information, .

Fig. 15 exemplifies a modification of the second embodiment. However, the above-described modifications can be applied to other optical systems as described above.

On the other hand, as shown in FIG. 16, the second metering section 49 may be additionally provided on the opposed portion of the first metering section 40 with respect to the contact surface 20. The light source unit 30 of FIG. 16 includes a plurality of light sources that emit light of different wavelengths.

In the structure shown in Fig. 16, light having a wavelength suitable for acquiring the shape of the fingerprint and the light having the wavelength of at least infrared or near infrared rays is irradiated toward the finger having the fingerprint formed thereon in the light source unit 30 and the light having the infrared or near- And the light scattered or reflected by the fingerprint 10 of the finger is acquired by the first photometry part 40. [

The second photometry unit 49 includes a second photometry unit for sensing light of a wavelength of infrared or near infrared rays irradiated by the light source unit 30. Of course, the first light metering section 40 further includes a first light metering element that senses light having a wavelength suitable for acquiring the shape of the fingerprint irradiated by the light source section 30. Or a first pass filter for passing only the wavelength band necessary for fingerprint recognition among the wavelength bands of the light irradiated from the light source part in front of the first photometry part 40, And a second pass filter for passing only the wavelength band necessary for acquiring blood vessel information among the wavelength bands of the irradiated light.

Regardless of which method is used, the optical information necessary for obtaining the blood vessel shape is photometrically photographed by the second photometry unit 49, and the information necessary for acquiring the fingerprint form is photometrically photographed by the first photometry unit 40, respectively.

The optical information processing section implements the blood vessel shape inside the living body from the optical information of the infrared or near infrared ray wavelength acquired by the photometry section as shown in FIG. 17, and implements the shape of the fingerprint image. Then, the optical information processing unit confirms the identity using both the image of the blood vessel shape and the image of the fingerprint shape. That is, in the fingerprint identification device, in the identification process for identifying a person having previously registered fingerprint and blood vessel information, it is checked whether the previously registered fingerprint and the blood vessel shape information match the recognized fingerprint and the vessel shape information, .

Although FIG. 16 exemplifies a modification of the second embodiment, the above-described modifications can be applied to other embodiments of the optical system as described above. 3, the light source unit 30 may include an annular base 32, and the first light metering unit 40 may be positioned at the center of the annular base, so that the base is rotated about the center of the annular shape .

Since the optical system described above can implement a plurality of light sources having different wavelengths and a polarizing filter having different directions in one apparatus, the principle of the fingerprint recognition that detects the shape information of the blood vessel described above and the other optical fingerprint recognition It is possible to implement them in combination. The greater the number of such combinations, the lower the possibility of using false fingerprints.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It is obvious that it can be done. Although the embodiments of the present invention have been described in detail above, the effects of the present invention are not explicitly described and described, but it is needless to say that the effects that can be predicted by the configurations should also be recognized.

10: Fingerprint
20: contact surface
30: light source part, first light source part
39: second light source
30-1, 30-n: first light source, nth light source
32: Base
40: a photometric unit, a first photometric unit
42:
42-1, 42-n: a first photometric element, an n-th photometric element
45: Pass filter
49: Second metering section
51: first polarizing filter
52: second polarizing filter
53: Third polarizing filter
55: beam splitter cube
56: split face
58: light absorbing film
a: first wavelength
b: second wavelength
c: Third wavelength

Claims (19)

Optically acquiring a shape of a fingerprint that is in contact with the contact surface (20); And
Irradiating light toward the fingerprint in a state in which the fingerprint is in contact with the contact surface (20), and acquiring biometric information of the finger on which the fingerprint is formed,
And determining that the acquired fingerprint is a fingerprint of the living body if the oxygen saturation calculated from the first wavelength light absorption amount of blood and the light absorption amount of the second wavelength of blood among the acquired bio-light information of the finger is within a predetermined range A fingerprint recognition method.
The method according to claim 1,
Wherein the light of the first wavelength is a light having a wavelength that has the same absorption rate of hemoglobin (Hb) and oxygen hemoglobin (HbO ₂ ).
The method according to claim 1,
Wherein at least one of the value of the first wavelength or the value of the second wavelength is changed each time the fingerprint is recognized.
The method according to claim 1,
Wherein the light irradiated toward the fingerprint includes light of the first wavelength and light of the second wavelength.
The method according to claim 1,
Extracting optical information of the first wavelength and optical information of the second wavelength from the obtained bio-light information of the finger to acquire optical information of the first wavelength and optical information of the second wavelength.
A light source part (30) including a base (32) provided with a light source;
A contact surface 20 provided at a position irradiated with light irradiated from a light source provided on the base and contacting the fingerprint 10;
A photometric unit 40 positioned adjacent to the base 32; And
And an optical information processing unit for processing optical information obtained through the light measuring unit 40 after the light emitted from the light source passes through the contact surface 20,
Wherein the optical information processing unit judges whether or not the oxygen saturation calculated from the first wavelength light absorption amount of blood and the light absorption amount of the second wavelength of blood is within a predetermined range.
The method of claim 6,
A first polarizing filter (51) disposed on a light path from the light source of the base to the contact surface (20); And
And a third polarizing filter (53) disposed on the optical path from the contact surface (20) to the photometric unit (40)
Wherein a first direction which is a polarization direction of the first polarizing filter and a third direction which is a polarization direction of the third polarizing filter are perpendicular to each other.
The method of claim 6,
A second polarizing filter (52) disposed on a light path from the light source of the base to the contact surface (20); And
And a third polarizing filter (53) disposed on the optical path from the contact surface (20) to the photometric unit (40)
The second direction being the polarization direction of the second polarizing filter and the third direction being the polarization direction of the third polarizing filter are parallel to each other.
The method of claim 6,
The base 32 has an annular shape,
And the photometric unit (40) is located at the center of the annular shape of the base.
The method of claim 9,
Wherein the base (32) is rotatable about an annular center.
The method of claim 9,
A first polarizing filter (51) disposed on a light path from the light source of the base to the contact surface (20); And
And a third polarizing filter (53) disposed on the optical path from the contact surface (20) to the photometric unit (40)
Wherein the first polarizing filter (51) and the third polarizing filter (53) are rotatable about an annular center of the base (32).
The method of claim 6,
Wherein the light source includes a light source that emits light of a first wavelength and a light source that emits light of a second wavelength.
The method of claim 6,
Wherein a unit of the photometric unit (40) is provided with a first photometric element for detecting light of a first wavelength and a second photometric element for detecting light of a second wavelength.
The method of claim 6,
A first pass filter for passing only light of a first wavelength and a second pass filter for passing only light of a second wavelength in front of the photometry part.
The method of claim 6,
Wherein at least one of the value of the first wavelength or the value of the second wavelength is changed each time a fingerprint is recognized.
The method of claim 6,
The contact surface 20 is a surface forming a long side of a prism having a trapezoidal shape,
The light source unit 30 is disposed on the oblique plane of the prism, and the light emitted from the light source unit 30 passes through the oblique plane of the prism and is irradiated onto the contact surface 20,
The photometric unit (40) is disposed on a side of a trapezoidal short side to receive light passing through a surface of a short side of the prism.
A light source part (30) including a base (32) provided with a light source;
A contact surface 20 provided at a position irradiated with light irradiated from a light source provided on the base and contacting the fingerprint 10;
A photometric unit 40 positioned adjacent to the base 32;
Having a split surface (56) disposed on the light path from the light source of the base to the contact surface (20) and on the light path leading from the contact surface (20) to the light measuring portion (40) A lit cube 55; And
And an optical information processing unit for processing optical information obtained through the light measuring unit 40 after the light emitted from the light source passes through the contact surface 20,
Wherein the optical information processing unit judges whether or not the oxygen saturation calculated from the first wavelength light absorption amount of blood and the light absorption amount of the second wavelength of blood is within a predetermined range. 18. The method of claim 17,
The installation surface of the light source unit 30 and the installation surface of the light metering unit 40 are not located on the surfaces of the beam splitter cube facing each other but are located on different surfaces with respect to the split surface 56 Fingerprint recognition device.
19. The method of claim 18,
Wherein the contact surface (20) is located on a face of the beam splitter cube (20) facing the photometric unit (40).

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