WO2012160680A1 - Optical characteristics measurement device and measurement control program - Google Patents

Abstract

Provided is an optical characteristics measurement device comprising: a light source including a plurality of unit light sources which, with respect to an object to be measured, can individually control emitted light beams and emit light beams of any colour from among a plurality of light beams having different spectral characteristics; a light detector which, for each light beam, receives a reflected light beam from the object to be measured; a measurement unit for measuring the optical characteristics of the object to be measured, from the amount of light received from the plurality of reflected light beams detected by the light detector; and a light-source control unit for controlling the light beams emitted by the light source and outputting, to the light source, information regarding the measurement result produced by the measurement unit.

Description

Optical characteristic measuring apparatus and measurement control program

The present invention relates to an optical characteristic measuring apparatus and a measurement control program for performing processing relating to measurement of optical characteristics of a measurement object.

Conventionally, light has been emitted to a measurement object, and spectroscopic analysis has been performed based on the reflected light or transmitted light.

FIG. 1 is a diagram for explaining an example of a conventional spectroscopic analysis. For example, the illumination light reflected from the measurement object 1 is adjusted to light having a specific spectrum by using the switching type color filter 2 or the like, and the reflected light is captured by the digital camera 3 or the like. There is a technique for obtaining a reflectance distribution.

An apparatus that measures the spectral characteristics of an object includes a so-called monochromator. FIG. 2 is a diagram illustrating an example of a monochromator. The first monochromator 4 and the second monochromator 5 shown in FIG. 2 increase the purity of the wavelength used for measurement. FIG. 3 is a diagram showing an example of a conventional color measuring device. The colorimetric device shown in FIG. 3 is provided with a light receiving element 8 that arranges multiple light emitting diodes 6 in close proximity and receives reflected light from the light projecting unit 7.

FIG. 4 is a diagram showing an example of a conventional spectrocolorimeter. As shown in FIG. 4, there is a technique including a condensing optical system 9 that condenses the output light flux of each light source to illuminate substantially the same point of the object to be measured.

Also, there is a technology having a display that provides color light passing through a test sample (object) and a detector that detects light output from the test sample.

JP 2000-292259 A JP 2005-517195 gazette

However, in the case of the conventional technology using a color filter or a monochromator, the entire apparatus becomes large and not excellent in portability, and the system price is expensive. Also, in the case of the prior art having a condensing lens, it is expensive because it has a condensing lens for ordinary consumers to use on a daily basis at home, and optical characteristics are easily measured. Is not portable.

Also, in the prior art using a display as a light source, it is necessary to provide a detector for detecting light passing through the object at a position facing the display with the object sandwiched therebetween, so portability is not good. Therefore, the conventional technology has a problem that it is not excellent in portability and the optical characteristics cannot be easily measured.

Therefore, the disclosed technology has been made in view of the above-described problems, and an object thereof is to provide an optical property measuring apparatus and a measurement control program that can improve portability and easily measure optical properties. To do.

An optical property measurement apparatus according to an aspect of the disclosure includes a plurality of unit light sources that can individually control light emission with respect to an object to be measured and emit light of any color among a plurality of lights having different spectral characteristics. An optical characteristic of the measurement object is measured from a light source, a photodetector that receives reflected light from the measurement object for each light, and a plurality of reflected light amounts detected by the light detector. A measurement unit; and a light source control unit that controls light emission of the light source and causes the light source to output information about a result measured by the measurement unit.

According to another aspect of the disclosure, a measurement control program causes a plurality of light beams having different spectral characteristics to be emitted from a light source including a plurality of unit light sources, and reflects the light from the measurement object for each light. Obtaining the received light amount of the reflected light from a photodetector that receives light, outputting information about the obtained plurality of received light amounts to another computer via a network, and returning information from the other computer, A computer executes processing to output via the light source.

According to the disclosed technology, portability can be improved and optical characteristics can be easily measured.

The figure explaining the example of the conventional spectroscopic analysis. The figure which shows an example of a monochromator. The figure which shows an example of the conventional colorimetry apparatus. The figure which shows an example of the conventional spectral colorimeter. The block diagram which shows an example of the hardware of an optical characteristic measuring apparatus. The block diagram which shows an example of a functional structure of an optical characteristic measuring apparatus. The figure for demonstrating the influence of regular reflection. The figure which shows the positional relationship (the 1) of an optical characteristic measuring apparatus and a measurement object. The figure which shows the positional relationship (the 2) of an optical characteristic measuring apparatus and a measurement object. The figure which shows the positional relationship (the 3) of an optical characteristic measuring apparatus and a measuring object. The figure which shows an example of the emission spectral characteristic of R, G, B of a display. The figure which shows an example of the sensitivity characteristic of R, G, B of a camera module. The flowchart which shows an example of the measurement control process in an optical characteristic measuring apparatus. FIG. 6 is a diagram illustrating an example of an optical characteristic measurement system in Embodiment 2. The block diagram which shows an example of a functional structure of the portable terminal device in Example 2, and a server.

DESCRIPTION OF SYMBOLS 10 Optical characteristic measuring apparatus 104 Control part 105 Camera module 106 Display 201 Light source 202 Light source control part 203 Photo detector 204 Received light quantity acquisition part 205 Judgment part 206, 301 Storage part 207 Measurement part 302 Output part

Hereinafter, examples will be described with reference to the drawings.

[Example 1]
The optical characteristic measurement apparatus according to the first embodiment is, for example, a portable apparatus having a display and a camera module, and uses a display as a light source and a camera module as a light detector. Hereinafter, the embodiment will be described by taking a portable device as an example. However, the present invention is not limited to this, and the present invention is also applicable to an information processing device in which a camera module is installed at a position where reflected light of light emitted from a display can be received. Is possible.

<Hardware>
First, the hardware of the optical characteristic measuring apparatus will be described. FIG. 5 is a block diagram illustrating an example of hardware of the optical characteristic measuring apparatus (portable apparatus) 10. The optical characteristic measuring apparatus 10 includes an antenna 101, a radio unit 102, a baseband processing unit 103, a control unit 104, a camera module 105, a display 106, a main storage unit 107, an auxiliary storage unit 108, and a terminal interface unit 109.

The antenna 101 transmits a radio signal amplified by the transmission amplifier and receives a radio signal from the base station. Radio section 102 performs D / A conversion on the transmission signal spread by baseband processing section 103, converts it to a high-frequency signal by orthogonal modulation, and amplifies the signal by a power amplifier. The radio unit 102 amplifies the received radio signal, A / D converts the signal, and transmits the signal to the baseband processing unit 103.

The baseband processing unit 103 performs baseband processing such as addition of error correction code of transmission data, data modulation, spread modulation, despreading of received signals, determination of reception environment, threshold determination of each channel signal, error correction decoding, etc. Do.

In addition, when the optical characteristic measuring apparatus 10 does not perform wireless communication, the antenna 101, the wireless unit 102, and the baseband processing unit 103 may be omitted.

The control unit 104 is, for example, a processor and performs wireless control such as transmission / reception of control signals. In addition, the control unit 104 executes a control program for measuring optical characteristics, which is stored in the auxiliary storage unit 108 and the like, and performs optical characteristic measurement processing described below.

The camera module 105 includes, for example, a CCD (Charge-Coupled Device) sensor or a CMOS (Complementary Metal-Oxide Semiconductor) sensor, and detects the amount of received light.

The display 106 is, for example, an LCD (Liquid Crystal Display) or an organic EL, and has a plurality of pixels. Each pixel can emit light having different spectral characteristics. For example, each pixel emits R, G, and B colors.

The main storage unit 107 is a ROM (Read Only Memory), a RAM (Random Access Memory), or the like, and a storage device that stores or temporarily stores programs and data such as an OS and application software that are basic software executed by the control unit 104 It is. For example, the main storage unit 107 stores the amount of light received by the camera module 105.

The auxiliary storage unit 108 is an HDD (Hard Disk Drive) or the like, and is a storage device that stores data related to application software and the like. The auxiliary storage unit 108 stores, for example, a control program for measuring optical characteristics and a measurement result.

The terminal interface unit 109 performs data adapter processing, interface processing with a handset and an external data terminal.

The camera module 105 is provided at a position where the reflected light of the light emitted from the display 106 can be received. For example, the camera module 105 is preferably provided on the same surface of the same housing as the display 106. This is to allow the reflected light of the light emitted from the display 106 to the measurement object to be received. The measurement object is a living tissue including skin such as a face and an arm, for example.

<Configuration>
FIG. 6 is a block diagram illustrating an example of a functional configuration of the optical property measurement apparatus 10. The optical characteristic measurement apparatus 10 illustrated in FIG. 6 includes a light source 201, a light source control unit 202, a photodetector 203, a received light amount acquisition unit 204, a storage unit 206, and a measurement unit 207.

The light source 201 is realized by, for example, the display 106, the photodetector 203 is realized by, for example, the camera module 105, and the storage unit 206 can be realized by, for example, the main storage unit 107 and / or the auxiliary storage unit 108. In addition, the light source control unit 202, the received light amount acquisition unit 204, and the measurement unit 207 can be realized by the control unit 104, the main storage unit 107 as a work memory, and the like, for example.

The light source 201 has a plurality of fine light sources as unit light sources, and emits a plurality of lights having different spectral characteristics to the measurement object. The fine light source is, for example, a pixel, but is not limited thereto, and may be a fine light source that can be controlled ON / OFF. Each of the fine light sources can emit light in different colors, for example, any one of R, G, and B. It is sufficient that there are at least a plurality of fine light sources that emit light of the first color and a plurality of fine light sources that emit light of the second color, and the light source 201 can emit a plurality of colors. The light source 201 controls light emission (ON), light emission stop (OFF), and the like for each fine light source by the light source control unit 202. In other words, the light source 201 can be said to be a light source composed of an assembly of unit light sources that can be individually controlled ON / OFF and has an area of 1/1000 or less of the total area of the light source.

The light source control unit 202 controls light emission and issuance stop for each light source, and controls which color light source among the light sources emits light. For example, when the optical characteristics are measured, the light source control unit 202 first emits light while shifting the light source that emits light by a predetermined position in order to check which position of the light source is regular reflection with respect to the measurement object. Next, the light source control unit 202 sequentially emits light having different spectral characteristics to light sources other than the light source that becomes regular reflection.

The photodetector 203 is a detector that detects electromagnetic energy such as light. The photodetector 203 receives, for example, reflected light of light emitted from the light source 201 with respect to the measurement object. In addition, it is desirable that the reflected light is not regular reflection light but scattered light.

FIG. 7 is a diagram for explaining the influence of regular reflection. As shown in FIG. 7, the light emitted from the light source 201 is reflected by the measurement object. At this time, a direction in which the incident angle θ _in and the reflection angle θ _ref are the same with respect to the vertical direction N from the measurement object is referred to as a regular reflection direction, and a direction in which the incident angle θ _in and the reflection angle θ _ref are different. Called the diffuse reflection direction. The reflected light in the regular reflection direction is referred to as regular reflection light, and the reflected light in the diffuse reflection direction is referred to as scattered light.

Specular reflection light includes a large color characteristic of the light source color, and scattered light includes a large color characteristic of the object color. Therefore, when it is desired to measure the optical characteristics of the measurement object, it is desirable to measure with scattered light without the influence of regular reflection.

Returning to FIG. 6, the received light amount acquisition unit 204 includes a determination unit 205, and performs regular reflection determination processing and received light amount acquisition processing.

The determination unit 205 determines whether or not the reflected light received by the photodetector 203 is regular reflected light. This determination process is a process performed before measuring the optical characteristics. Therefore, the received light amount acquisition unit 204 first performs a determination process by the determination unit 205 on the received light amount of the reflected light acquired from the photodetector 203.

The determination unit 205 acquires, for example, the amount of light received by a light source at a predetermined position, and determines the light source that has the maximum amount of light received. The determination unit 205 determines that the light source having the maximum received light amount is a light source that is regularly reflected with respect to the measurement target.

Also, the determination unit 205 may determine whether or not a threshold value is exceeded with respect to the amount of light received by the light source at each predetermined position. In this case, the light source at a predetermined position that exceeds the threshold is determined as a light source that is regularly reflected with respect to the measurement object. The threshold value may be set to an appropriate value through experiments or the like. The determination unit 205 notifies the light source control unit 202 of the light source or the position of the light source that becomes regular reflection.

Next, the received light amount acquisition unit 204 sequentially acquires the received light amount of reflected light from the photodetector 203 after the regular reflection determination process, and the acquired received light amount for each light (for example, R, G, B) is stored in the storage unit 206. Write (record). For example, the received light amount of R reflected light is A1, the received light amount of G reflected light is A2, and the received light amount of B reflected light is A3.

The storage unit 206 stores data of received light amounts A1 to A3 for each light. The amount of received light is, for example, 10 to 500 lx (lux). The amount of received light varies depending on the model of the optical characteristic measurement device (portable device) 10, the distance between the camera and the measurement object (skin), the influence of the environment (the influence of disturbance light), and the like. The storage unit 206 may store the position of the light source that is regularly reflected.

The measurement unit 207 measures the optical characteristics of the object (measurement target) based on the received light amount data stored in the storage unit 206. Examples of the optical characteristics include spectral reflectance and spectral colorimetry.

Spectral reflectance measures the properties of physical properties themselves (for example, the spectral properties of pigments), while spectral colorimetry measures the apparent color of an object. Hereinafter, a case where the measurement unit 207 calculates spectral reflectance or spectral colorimetry will be described.

(Spectral reflectance)
The measurement unit 207 calculates the spectral reflectance using the data of the received light amounts A1, A2, and A3 as follows.

First, assuming that C (λ) is the spectral characteristic of the photodetector 203, E (λ) is the spectral characteristic of the light source 201, and r (λ) is the spectral reflectance of an object (for example, human skin), the output of the photodetector 203. v is calculated by the following equation (1).

測定対象の波長域としては、例えば４００～７００ｎｍとする。

The wavelength range to be measured is, for example, 400 to 700 nm.

Here, when r represents a row vector composed of l elements representing the spectral reflectance of the object, equation (1) can be represented by equation (2).

　例えば、ｖは、光検出器２０３の測定値Ａ１、Ａ２、Ａ３を用いることで、
ｖ＝（Ａ１，Ａ２，Ａ３）
という行ベクトルとして表現できる。

For example, by using measured values A1, A2, and A3 of the photodetector 203, v is
v = (A1, A2, A3)
Can be expressed as a row vector.

The matrix F is Equation (3).

　行列Ｆは、光源２０１と光検出器２０３の分光特性に対応するｌ×ｌの対角行列となる。ここで、分光反射率を主成分分析する。例えば、共分散表列の固有分解を行うことにより、主成分ベクトルｂｉを基底として、式（４）のように展開できる。

The matrix F is an l × l diagonal matrix corresponding to the spectral characteristics of the light source 201 and the photodetector 203. Here, the principal component analysis is performed on the spectral reflectance. For example, by performing eigendecomposition of the covariance table sequence, the principal component vector bi can be used as a basis and can be expanded as shown in Equation (4).

　ｗｉは、主成分ベクトルに対する重み係数である。

wi is a weighting factor for the principal component vector.

Also, if a technique called low-dimensional linear approximation is used, it is possible to approximate a vector with a small number of bases without using all bases.

That is, equation (5) holds.

　式（５）を式（２）に代入すると、式（６）が得られる。

Substituting equation (5) into equation (2) yields equation (6).

　ここで、ＦＢは、正方行列であり、行列Ｆの基底が独立であるとすると、ＦＢは正則になり、逆行列を持つ。よって、式（６）をｗについて解くと、式（７）になる。

Here, FB is a square matrix, and assuming that the basis of the matrix F is independent, FB is regular and has an inverse matrix. Therefore, when equation (6) is solved for w, equation (7) is obtained.

　式（７）を式（５）に代入すると、分光反射率ｒが、次の式（８）により求められる。

By substituting equation (7) into equation (5), the spectral reflectance r is obtained by the following equation (8).

　測定部２０７は、上記アルゴリズムを用いることで、物体からの反射光量ベクトルｖ＝（Ａ１，Ａ２，Ａ３，・・・）から物体の分光反射率ｒを求めることができる。上記算出アルゴリズムの詳細は、"津村徳道共著　「重回帰分析によるマルチバンド画像からの分光反射率の推定」　応用物理学会分科会日本光学会　Japanese journal of optics 27(7), 384-391, 1998-07-10"を参照されたい。

The measurement unit 207 can obtain the spectral reflectance r of the object from the reflected light quantity vector v = (A1, A2, A3,...) Using the above algorithm. For details of the above algorithm, see “Tokumichi Tsumura,“ Estimation of Spectral Reflectance from Multiband Images by Multiple Regression Analysis ”. Japanese Society of Applied Physics 27 (7), 384-391, 1998- See 07-10 ".

(Spectral colorimetry)
Spectral colorimetry measures the chromaticity of an object. In order to express the color (color difference) of an object, there is a general idea of “CIE.Lab (L * a * b *)”.

“L *” represents lightness (brightness level) from the object, “a *” represents chromaticity covering from green to red, and “b *” represents chromaticity covering from blue to green. Represents.

The measurement unit 207 calculates spectral colorimetry by using a conversion formula defined by the International Commission on Illumination (CIE) using data of the received light amounts A1, A2, and A3.

The measurement unit 207 multiplies the data of the received light amounts A1, A2, and A3 by coefficients called tristimulus values (X stimulus value, Y stimulus value, and Z stimulus value) and integrates them to obtain “X value”. ”,“ Y value ”, and“ Z value ”. The stimulus value represents the perceptual sensitivity of the L, M, and S pituitary glands that feel the light of the color of the human eye.

The measurement unit 207 can obtain “L * a * b *” by the conversion formula of the International Lighting Commission from the “X value”, “Y value”, and “Z value”.

The measuring unit 207 may calculate the above-described spectral reflectance or spectral colorimetry in order to measure optical characteristics. Which is calculated may be set in advance or may be selected by the user.

The measuring unit 207 may output to the display 106, for example, in order to inform the user of the optical characteristics of the measured object (measurement object). That is, the measurement unit 207 may instruct the light source control unit 202 to output information on the measured optical characteristics of the object, and the light source control unit 202 may control the light source 201 to output information to the light source 201. At this time, the display 106 displays the measurement result.

<Regular reflection determination processing>
Next, regular reflection determination processing will be described using a specific example. FIG. 8 is a diagram showing a positional relationship (part 1) between the optical property measuring apparatus 10 and the measurement object. In the optical characteristic measuring apparatus 10 shown in FIG. 8, taking a portable device as an example, the longitudinal direction of the display 106 is the X direction, and a camera module (so-called in-camera) 105 is provided above the display 106.

Moreover, the housing | casing 20 shows the housing | casing by the side of the display 106 of a foldable portable apparatus. The housing 20 includes a display 106 and a camera module 105. Note that the portable device is not necessarily foldable.

P (x, y) shown in Fig. 8 represents a pixel of the display 106 or a collection of pixels. The pixel functions as a light source that emits light having different spectral characteristics of RGB. Each pixel can be controlled ON / OFF independently.

Here, the regular reflection determination process will be described with reference to FIG. In the example shown in FIG. 8, the light source control unit 202 emits light in order from P (1, y), P (2, y), P (3, y). The light at this time may be RGB light, but here, in order to increase the amount of light, all RGB light is emitted to be white light.

In this example, P (1, y) represents all the pixels in the column in the Y direction (short direction) whose coordinates in the X direction are 1, but not all the columns. One or more pixels may be represented. It may be set in advance whether to make all the rows or a predetermined number.

Further, when the amount of received light is smaller than the threshold value, there are a plurality of X directions in the order of P (1, y) and P (2, y), p (3, y) and P (4, y). The pixels may emit light together. Note that this threshold is set to an appropriate value through experiments or the like.

The light detector 203 detects reflected light from the measurement object. The received light amount acquisition unit 204 acquires the received light amount of the reflected light, and performs regular reflection determination processing by the determination unit 205. For example, the determination unit 205 compares the acquired amounts of received light and determines the position of the pixel that has the maximum received light amount.

In the example shown in FIG. 8, the light emitted from P (1, y), P (2, y), and P (3, y) is regularly reflected by the measurement object (for example, human skin). And For example, with respect to the light emitted from P (1, y), the vertical incident angle θ _i1 and the reflection angle θ _r1 with respect to the measurement object are the same. Therefore, the determination unit 205 determines that the amount of received light is the maximum.

The determination unit 205 notifies the light source control unit 202 of P (1, y) to P (3, y) determined to be regular reflection. The light source control unit 202 stops the light emission of P (1, y) to P (3, y), and causes the other pixels to emit light in the order of R, G, B, for example. As a result, the light detector 203 does not need to detect light with excessive intensity due to regular reflection, and can receive reflected light (scattered light) affected by the color characteristics of the measurement object.

FIG. 9 is a diagram showing a positional relationship (part 2) between the optical property measuring apparatus 10 and the measurement object. In the example shown in FIG. 9, the light emitted from P (n, y), P (n + 1, y), and P (n + 2, y) is regularly reflected by the measurement object (for example, human skin). And For example, for light emitted from P (n, y), the incident angle θ _{in the} vertical direction with respect to the object to be measured and the reflection angle θ _rn are the same. Therefore, the determination unit 205 determines that the amount of received light is the maximum.

The determination unit 205 notifies the light source control unit 202 of P (n, y) to P (n + 2, y) determined to be regular reflection. The light source control unit 202 stops the light emission of P (n, y) to P (n + 2, y) and causes the other pixels to emit light in the order of R, G, B, for example. As a result, the photodetector 203 does not need to detect light with excessive intensity due to regular reflection, and can enter reflected light affected by the color characteristics of the measurement object.

Further, since the positional relationship between the measurement object and the optical property measuring device 10 is different every time it is measured, it is possible to specify the light source position that becomes regular reflection each time and stop the light emission of the specified light source. .

8 and 9, pixels that are regularly reflected in the longitudinal direction (X direction) of the display 106 are determined. However, the same determination may be performed for the short direction (Y direction) of the display 106. Good.

FIG. 10 is a diagram showing a positional relationship (part 3) between the optical property measuring apparatus 10 and the measurement object. FIG. 10 shows an example in which the optical property measuring apparatus 10 is viewed from the short side direction of the display 106.

In the example shown in FIG. 10, it is assumed that light emitted from P (x, s), P (x, s + 1), and P (x, s + 2) is regularly reflected by the measurement object. For example, for light emitted from P (x, s), the vertical incident angle θ _is and the reflection angle θ _rs are the same with respect to the measurement object. Therefore, the determination unit 205 determines that the amount of received light is the maximum.

The determination unit 205 notifies the light source control unit 202 of P (x, s) to P (x, s + 2) determined to be regular reflection. The light source control unit 202 stops P (x, s) to P (x, s + 2), and causes the other pixels to emit light in the order of R, G, and B, for example. As a result, the photodetector 203 does not need to detect light with excessive intensity due to regular reflection, and can enter reflected light affected by the color characteristics of the measurement object.

In the example shown in FIG. 10, P (x, s) represents all pixels in the column in the X direction where the coordinate in the Y direction is s. A plurality of pixels may be represented.

When the regular reflection determination process is performed in the X direction and the Y direction, the light source control unit 202 stops issuing so that the pixels determined to be regular reflection in the X direction and the Y direction are not used for the measurement of optical characteristics. It may be.

As described above, the regular reflection determination process is a process for determining whether the light emitted from which pixel in the display 106 is regularly reflected from the measurement object. The regular reflection determination process may be performed at least in the longitudinal direction (X direction) of the display 106, and may be performed in the short direction (Y direction) if necessary.

The pixel (light source) determined to emit regular reflected light in the regular reflection determination process is controlled by the light source control unit 202 to stop light emission during the optical characteristic measurement process.

<Luminescent color>
Next, the emission color emitted from the light source 201 will be described. FIG. 11A is a diagram illustrating an example of emission spectral characteristics of R, G, and B of the display 106. FIG. 11B is a diagram illustrating an example of sensitivity characteristics of R, G, and B of the camera module 105.

In order to perform spectroscopic measurement advantageous for the SN ratio, it is desirable that the spectral distribution diagrams overlap as much as possible with respect to the spectral characteristics of the emitted color and the sensitivity characteristics of the camera module 105 that receives the light.

The solid line shown in FIG. 11A represents the case where blue is emitted, the dotted line represents the case where green is emitted, and the alternate long and short dash line represents the case where red is emitted. The emitted red, green, and blue are represented by r1, g1, and b1, respectively.

The solid line shown in FIG. 11B represents the case where blue is received, the dotted line represents the case where green is received, and the alternate long and short dash line represents the case where red is received. The received red, green, and blue are represented by R1, G1, and B1, respectively.

Referring to FIGS. 11A and 11B, r1-R1, g1-G1, and b1-B1 have more signals and a higher S / N ratio. However, at other wavelengths, the signal is low and the SN ratio is deteriorated.

On the other hand, what has a high S / N ratio in a relatively large number of wavelength regions is a region where the overlapping portion of the light emission spectrum of the display 106 and the light reception spectrum of the camera module 105 is likely to be large. According to this viewpoint, the SN ratio is relatively high in the regions such as g1-B1, g1-R1, and b1-G1.

Therefore, in order to measure the optical characteristics, it is preferable that the light source 201 emits light of at least two colors of blue (B) and green (G). The emission color may be at least two colors, and the color is not limited to any one of R, G, and B.

<Operation>
Next, the operation of the optical property measuring apparatus 10 will be described. FIG. 12 is a flowchart illustrating an example of a measurement control process in the optical property measurement apparatus 10. The flow shown in FIG. 12 includes regular reflection determination processing and received light amount measurement processing. In the process shown in FIG. 12, the pixels in the X direction are controlled, and all the pixels in the Y direction whose coordinates in the X direction are n are represented as Pn.

In step S101, the determination unit 205 sets X1 = 0. Let X1 represent the maximum amount of received light.

In step S102, the determination unit 205 determines whether n ≦ N. N represents the maximum number of pixels in the X direction of the display 106. If n ≦ N (step S102—YES), the process proceeds to step S103, and if n> N (step S102—NO), the process proceeds to step S107.

In step S103, after the light emission control of Pn by the light source control unit 202, the determination unit 205 determines whether SPn ≧ X1. SPn represents the amount of reflected light received by the measurement object when Pn is emitted. If SPn ≧ X1 (step S103—YES), the process proceeds to step S104, and if SPn <X1 (step S103—NO), the process proceeds to step S106.

In step S104, the determination unit 205 sets X1 = SPn and substitutes (records) SPn into X1.

In step S105, the determination unit 205 sets m = n, and substitutes (records) n for m. It progresses to step S106 after the process of step S105.

In step S106, the light source control unit 202 sets n = n + 1. After the process of step S106, the process returns to step S102.

The processing in steps S101 to S106 is regular reflection determination processing, and it can be understood that the pixel at the position recorded in m is a pixel that emits light that is regularly reflected.

Here, m stores only one position in the X direction. However, if there are a plurality of positions in the X direction where the amount of received light is the maximum value, a plurality of positions may be stored. In the above processing, only the position where the amount of received light reaches the maximum value is stored. However, since the measurement error is included, light reception within a predetermined range including the maximum value (for example, within several percent below the maximum value). You may make it memorize | store the position of Pn used as quantity. Further, regular reflection determination processing in the Y direction may be additionally performed.

In step S107, when the light source control unit 202 acquires the position of the pixel that is regularly reflected from the determination unit 205, the light source control unit 202 sets Pn at a position other than m to emit light by setting the first illumination light mode. The first illumination light is, for example, R.

In step S108, the received light amount acquisition unit 204 acquires the received light amount of the reflected light detected by the photodetector 203. The received light amount acquisition unit 204 stores the acquired R received light amount in the storage unit 206. The amount of received R light is A1.

In step S109, the light source control unit 202 causes Pn at a position other than m to be set to the second illumination light mode to emit light. The second illumination light is, for example, G.

In step S110, the received light amount acquisition unit 204 acquires the received light amount of the reflected light detected by the photodetector 203. The received light amount acquisition unit 204 stores the acquired received light amount of G in the storage unit 206. The amount of light received by G is A2.

In step S111, the light source control unit 202 causes Pn at a position other than m to be set to the third illumination light mode to emit light. The third illumination light is, for example, B.

In step S112, the received light amount acquisition unit 204 acquires the received light amount of the reflected light detected by the photodetector 203. The received light amount acquisition unit 204 stores the acquired B received light amount in the storage unit 206. The amount of light received by B is A3. Note that the order of RGB illumination (light emission) is random. In addition, among RGB, there may be a color that does not illuminate (emit light). For example, when R illumination is not performed, the processes in steps S107 and S108 may not be executed.

This makes it possible to remove the influence of regular reflection and measure the amount of reflected light from the measurement object.

When the received light amount measurement process is completed for each light having different spectral characteristics, the measurement unit 207 performs an optical characteristic calculation process. The measurement unit 207 performs calculation processing of either the spectral reflectance or the spectral colorimetry described above using the data of the received light amounts A1, A2, and A3. Information obtained as a result of the calculation process is output to the light source 201.

Further, the light source control unit 202 can increase or decrease the area of the light emitting pixel according to the magnitude of the received light amount acquired by the received light amount acquiring unit 204. Thereby, it is possible to measure an appropriate amount of received light. For example, when the received light amount acquired by the received light amount acquisition unit 204 is larger than a threshold value, the light source control unit 202 decreases the area of the pixel that emits light.

Further, the process of measuring the optical characteristics may be realized as one application. In this case, when this application is executed, the position of the light source that becomes regular reflection is first determined, and then the light source other than the light source that becomes regular reflection is emitted to detect the received light amount of the reflected light. Characteristics are calculated.

As described above, according to the first embodiment, the optical characteristics can be easily measured with a device having excellent portability such as a portable device. Further, according to the first embodiment, by performing the regular reflection determination process, it is possible to selectively emit a light source that does not undergo regular reflection with respect to a plurality of fine light sources, and to reduce measurement result errors. Can do.

In addition, since it is assumed that the user performs measurement by holding the optical property measuring apparatus 10 in his / her hand, the angle at which the light is irradiated with respect to the measurement object (human skin) may be different for each measurement. Many. Therefore, in Example 1, the position of the light source that causes regular reflection can be detected each time, and the position of the light source that emits light can be determined each time the optical characteristics are measured.

Moreover, when the measurement object is human skin, according to Example 1, by measuring the spectral characteristics, it is possible to easily measure the color of the skin and manage the daily skin condition. Become.

In addition, since the optical property measuring apparatus 10 in Example 1 can be mounted on a portable device, it is not necessary to use expensive parts such as a condensing lens, it is excellent in economy, and further downsizing can be achieved. Is possible.

[Example 2]
Next, an optical characteristic measurement system in Example 2 will be described. In Example 2, optical characteristics are measured using a cloud service. In the second embodiment, a portable terminal device will be described as an example of the optical characteristic measuring device.

FIG. 13 is a diagram illustrating an example of an optical characteristic measurement system according to the second embodiment. In the example shown in FIG. 13, the mobile terminal device 30 receives the reflected light of the measurement object, and transmits the received light amount data to the cloud-side server 50 via the network 40. The server 50 calculates optical characteristics based on the received light amount data, and transmits the measurement result to the mobile terminal device 30.

In addition, since the hardware of the portable terminal device 30 in Example 2 is the same as that of the optical characteristic measuring apparatus 10 in Example 1, the description is abbreviate | omitted. Note that the mobile terminal device 30 includes an antenna 101, a wireless unit 102, and a baseband processing unit 103.

<Configuration>
Next, the configuration of the mobile terminal device 30 and the server 50 will be described. FIG. 14 is a block diagram illustrating an example of functional configurations of the mobile terminal device 30 and the server 50 according to the second embodiment. In the configuration of the mobile terminal device 30 illustrated in FIG. 14, the same reference numerals are given if the configuration is the same as the configuration illustrated in FIG. 6, and description thereof is omitted.

The storage unit 301 stores the received light amount data acquired by the received light amount acquisition unit 204. In addition, the storage unit 301 stores the measurement result of the optical characteristics received by the output unit 302 from the network. The measurement result stored in the storage unit 301 may be displayed on a display. The storage unit 301 can be realized by, for example, a main storage unit and / or an auxiliary storage unit.

The output unit 302 outputs (transmits) each received light amount data to the server 50 when the received light amount data corresponding to each light having different spectral characteristics is stored in the storage unit 301. In addition, when transmitting the data of each received light amount, the output unit 302 may output identification information for identifying the user such as a user ID in association with each other. The output unit 302 receives the spectral characteristic measurement result from the server 50. The output unit 302 can be realized by the antenna 101 or the wireless unit 102, for example.

In the first embodiment, the light source control unit 202 outputs the measurement result from the measurement unit 207 to the light source 201, but in the second embodiment, the measurement result received from the server 50 is received from the output unit 302 and output to the light source 201. .

Next, the functional configuration of the server 50 will be described. A server 50 illustrated in FIG. 14 includes a communication unit 501, a measurement unit 502, and a storage unit 503.

The communication unit 501 transmits and receives data via the network 40, for example, receives light reception amount data from the mobile terminal device 30, and transmits spectral characteristic measurement results to the mobile terminal device 30.

The measuring unit 502 has the same function as the function of the measuring unit 207 in the first embodiment. The measurement unit 502 acquires the received light amount data from the communication unit 501 and calculates the spectral reflectance or the spectral colorimetry. The measurement unit 502 writes the calculated optical characteristics in the storage unit 503.

The storage unit 503 stores the optical characteristics calculated by the measurement unit 502. In this case, the storage unit 503 may store a plurality of measurement results for each measured user. For example, for each user, the storage unit 503 stores the measured date and the measurement result of the day in association with each other.

The communication unit 501 can be realized by, for example, a network interface unit, the measurement unit 502 can be realized by, for example, a processor, and the storage unit 503 can be realized by, for example, an HDD.

<Operation>
Next, the operation of the optical characteristic measurement system in Example 2 will be described. The mobile terminal device 30 executes regular reflection determination processing, received light amount detection processing, and received light amount output processing. The server 50 executes optical characteristic measurement (calculation) processing and measurement result output processing.

Each process executed by the mobile terminal device 30 may be realized by one application. For example, by executing this application, regular reflection determination processing, received light amount measurement processing, and received light amount output processing may be executed, and measurement result reception processing and display processing may be executed.

As described above, according to the second embodiment, it is possible to obtain the same effect as the first embodiment while reducing the processing load of the mobile terminal device 30 using the cloud service.

Also, the optical characteristic measuring device in the first and second embodiments can be mounted not only on the mobile terminal device but also on other devices. For example, the present invention can be applied to an electronic device including a display and a camera.

Further, by recording a program for executing the processing in the above-described optical characteristic measuring apparatus in a ROM or the like, each processing in each embodiment can be executed by a computer.

It is also possible to record the program on a recording medium, and cause the portable terminal device or electronic device to read the recording medium on which the program is recorded, thereby realizing the above-described processes on the portable terminal device or electronic device. .

The recording medium is a recording medium that records information optically, electrically or magnetically, such as a CD-ROM, flexible disk, magneto-optical disk, etc., and information is electrically recorded such as ROM, flash memory, etc. Various types of recording media such as a semiconductor memory can be used.

The embodiment has been described in detail above, but is not limited to the specific embodiment, and various modifications and changes can be made within the scope described in the claims. It is also possible to combine all or a plurality of the components of the above-described embodiments.

Claims (7)

A light source including a plurality of unit light sources capable of individually controlling light emission and emitting light of any color among a plurality of lights having different spectral characteristics;
For each light, a photodetector that receives reflected light from the measurement object;
A measurement unit that measures optical characteristics of the measurement object from the amounts of received reflected light detected by the photodetector; and
An optical characteristic measurement apparatus comprising: a light source control unit that controls light emission of the light source and causes the light source to output information related to a result measured by the measurement unit. The light source control unit according to claim 1, wherein the light source control unit further controls whether or not each of the unit light sources is caused to emit light based on the received light amount of the reflected light detected by the photodetector. A determination unit that determines whether the amount of received light is regular reflection light;
The light source controller is
The optical characteristic measuring apparatus according to claim 2, wherein when it is determined that the amount of received light is specularly reflected light, the light emission of the unit light source that emits the light that becomes the specularly reflected light is stopped. The light source controller is
A part of the plurality of unit light sources is caused to emit light in order in the vertical direction or the horizontal direction,
The determination unit
The optical characteristic measuring apparatus according to claim 3, wherein the determination as to whether or not the reflected light is regular reflection light is performed in order for each of the partial unit light sources. The optical property measuring apparatus according to any one of claims 1 to 4, wherein the light source and the photodetector are provided in the same casing. 6. The optical characteristic measuring apparatus according to claim 5, wherein the light source and the photodetector are provided on the same surface of the same casing. From a light source including a plurality of unit light sources, a plurality of lights having different spectral characteristics are emitted to a measurement object,
For each light, obtain the amount of reflected light received from a photodetector that receives the reflected light from the measurement object;
Output the acquired information about the received light amount to another computer via a network,
A measurement control program for causing a computer to execute processing for outputting information returned from the other computer via the light source.

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