TWI867518B - Three-dimensional image scanning device - Google Patents

Abstract

A three-dimensional image scanning device includes a line-scanning light module, a area-scanning light module, an image capturing module, a motion stage and a control module. The line-scanning light module projects a line light along an incident angle on an object to-be-measured. The area-scanning light module projects an area light along the same incident angle on the object to-be-measured. The image capturing module captures the line light or the area light reflected by the object to-be-measured, so as to obtain the first line image or an area image. The motion stage controls a relative movement between the object to-be-measured, the line-scanning light module, the area-scanning light module and the image capturing module , so as to perform scanning.

Description

Stereoscopic image scanning device

The present invention relates to a stereoscopic image scanning technology, and more particularly to a stereoscopic image scanning device combining line scanning and surface scanning technology.

Automated optical inspection quality control has been carried out on various production lines in the electronics industry for many years. In the early days, it was carried out by random inspection. In recent years, due to the prevalence of automated production concepts such as Industry 4.0 and big data intelligent analysis, most of them have been inspected piece by piece. Since the production line attaches importance to production efficiency, the inspection speed is very demanding; the three-dimensional imaging technology used by the automated optical inspection (AOI) equipment on the production line is mainly line scanning technology and surface scanning technology. Both belong to triangulation in terms of the main classification of technology. Among them, the line scanning technology architecture is relatively simple. When implemented, the energy of the measurement signal will be concentrated in a single line area, which can enhance the signal strength. It is applicable to imaging of surfaces with high and low reflectivity, and is the most common three-dimensional imaging technology. In recent years, due to the significant increase in the bandwidth of industrial cameras and the ability to switch the motion area, it is common to see industrial cameras used in combination with laser light sources for imaging. One of the characteristics of line scanning is that its measurement results will be affected by the error (Mechanical Runout) of the motion platform it is used on, so there are higher requirements for the precision and vibration specifications of the motion platform. In addition, when the scale of the object to be tested tends to be fine, but the test area is large and concentrated, line scanning can generally provide the best scanning speed; on the other hand, surface scanning technology projects a structured light source onto the object to be tested, and calculates the three-dimensional appearance of the object to be tested by the changes in the structured light source. A large area can be measured each time, and three-dimensional compensation can be performed between each measurement area by overlapping the area, so it is relatively less susceptible to motion platform error interference. In addition, due to the mechanical movement characteristics of the motion platform, when the test area is locally discrete, surface scanning technology can achieve the best balance between scanning speed and accuracy.

On the other hand, consumer electronics have been developing towards being thinner, lighter, and smaller in recent years, and their functions are highly diversified. The complexity of products is constantly increasing, resulting in increasingly dense and delicate chip wiring, which has led to rapid development of advanced semiconductor packaging processes and a significant increase in the demand for testing. Although the bumps are concentrated in the chip area, due to the fan-out packaging characteristics, there may be two different types of detection demand concentrated areas and local discrete areas on the substrate at the same time. How to achieve the best balance between scanning speed and accuracy has become a new problem.

In view of this, based on the structural similarity of triangulation, an embodiment of the present invention proposes a stereoscopic image scanning device, including a linear scanning light module, a plane scanning light module, an image capture module, a moving platform and a control module. The linear scanning light module is used to project linear light onto the object to be measured along an incident angle. The plane scanning light module is used to project plane light onto the object to be measured along the same incident angle. The image capture module is used to capture the linear light or plane light reflected by the object to be measured, thereby obtaining a first line image or a plane image. The moving platform is used to control the relative movement between the object to be measured, the linear scanning light module, the plane scanning light module and the image capture module, so as to scan the object to be measured along a scanning direction.

According to the stereoscopic image scanning device proposed in the embodiment of the present invention, the combined optical path can combine the advantages of line scanning and surface scanning, and the scanning type can be switched according to the actual characteristics of the object to be measured to achieve the optimization of scanning speed and accuracy. By sharing components and optical paths, costs can be reduced, and the equipment volume can be further optimized. In addition, the leading area of the surface scan can be used to determine whether the light source intensity of the line scan needs to be adjusted or compensated. The trailing area of the surface scan can also be used to compare the line scan results, and the relative error can be used to determine whether the motion platform is stable, and the large area height obtained by the surface scan can be used to compensate for the motion variation of the motion platform and improve the measurement accuracy.

Referring to FIG. 1 , it is a schematic diagram of the structure of a stereoscopic image scanning device of an embodiment of the present invention. The stereoscopic image scanning device includes a linear scanning light module 10, a planar scanning light module 20, an image capture module 30, a stage 40, a moving platform 50, and a control module 60. The linear scanning light module 10 is used to project a linear light onto the stage 40 along an incident angle. The planar scanning light module 20 is used to project a planar light onto the stage 40 along the same incident angle. The stage 40 is used to carry a test object 90. The image capture module 30 is used to capture the linear light and the planar light reflected by the stage 40 and the test object 90, thereby obtaining a line image (hereinafter referred to as the first line image 111) and a planar image 211. The control module 60 is coupled to and controls the linear scanning light module 10, the plane scanning light module 20, the image capture module 30 and the motion platform 50. The control module 60 is used to output control signals to the linear scanning light module 10 and the plane scanning light module 20 respectively to control whether the linear scanning light module 10 and the plane scanning light module 20 are enabled and the corresponding operations. When line scanning is required, the linear scanning light module 10 performs corresponding actions according to the received control signal; when surface scanning is required, the plane scanning light module 20 performs corresponding actions according to the received control signal. The motion platform 50 is used to control the relative movement between the carrier 40 (the object to be measured 90) and the linear scanning light module 10, the plane scanning light module 20 and the image acquisition module 30, so as to scan the object to be measured 90 along a scanning direction. For example, the motion platform 50 cooperates with the linear scanning light module 10 to control the movement of the carrier 40 to perform a line scan or a surface scan on the object to be measured 90 along a scanning direction. However, the present invention is not limited to this. In some embodiments, the carrier 40 may be fixed, and the motion platform 50 controls the linear scanning light module 10, the plane scanning light module 20 and the image acquisition module 30 to move relative to the carrier 40.

In some embodiments, the control module 60 switches power supply to the linear scanning light module 10 and the plane scanning light module 20 according to demand. When line scanning is required, power is supplied to the linear scanning light module 10 and power supply to the plane scanning light module 20 is temporarily stopped. When surface scanning is required, power is supplied to the plane scanning light module 20 and power supply to the linear scanning light module 10 is temporarily stopped.

In some embodiments, the linear scanning light module 10 and the planar scanning light module 20 project a signal onto the carrier 40 along a direction, and the angle formed by the linear scanning light module 10 and the normal direction of the supporting surface of the carrier 40 is equal to the angle formed by the direction of the signal reflected by the carrier 40 and the normal direction of the supporting surface of the carrier 40 (that is, the incident angle is equal to the reflection angle), which can enhance the signal reflected by the supporting surface of the carrier 40.

In some embodiments, the linear scanning light module 10 and the plane scanning light module 20 project a signal onto the carrier 40 along a direction, and the angle formed by the linear scanning light module 10 and the normal direction of the supporting surface of the carrier 40 is not equal to the angle formed by the direction of the signal reflected by the carrier 40 and the normal direction of the supporting surface of the carrier 40 (that is, the light path is not designed according to the law of reflection). This can enhance the surface scattered signal of the object 90 to be measured and prevent the surface scattered signal of the object 90 to be covered by the reflected signal of the supporting surface of the carrier 40.

In some embodiments, the linear scanning light module 10 is a laser light source that projects linear light in a line scanning manner. In some embodiments, the linear scanning light module 10 is a light emitting diode array that has light emitting diodes arranged in a straight line to project linear light.

In some embodiments, the plane scanning light module 20 includes a digital micromirror device (DMD) or liquid crystal on silicon (LCOS) to reflect light from a light source (such as a light emitting diode) to form a plane light. In some embodiments, the light source is built into the plane scanning light module 20. In other embodiments, the plane scanning light module 20 receives light output by an external light source.

In some embodiments, the planar scanning light module 20 includes a micro-LED display (Micro LED Display) and an LCD (Liquid Crystal Display).

In some embodiments, the plane scanning light module 20 includes a light source and a light mask. The light mask has a specific analog pattern, so that the light emitted by the light source passes through the light mask to form a plane light corresponding to the specific analog pattern.

In some embodiments, the image capture module 30 includes more than one camera unit (such as the first camera unit 31, the second camera unit 32 and the color camera unit 33 described below). The camera unit includes one camera or multiple cameras. If the camera unit includes multiple cameras, it also includes a splitter to split the light to be captured into multiple light paths, and each light path is provided with a camera to receive the split light to be captured. In this way, multiple cameras can be used to capture images at the same time to speed up the capture speed.

In some embodiments, the motion platform 50 is a motion platform with more than one dimension, so that the carrier 40 moves parallel to the scanning direction.

In some embodiments, the control module 60 is an electronic device such as a microcontroller, an embedded controller, a microcomputer, or a computer that has control signal transmission capabilities and data calculation and processing capabilities.

FIG. 2A to FIG. 2C are schematic diagrams of the first line image 111 and the plane image 211 captured at time t1, t2, and t3, respectively. Referring to FIG. 1 and FIG. 2A to FIG. 2C together, since the linear scanning light module 10 and the plane scanning light module 20 project light to the stage 40 along the same incident angle, and the two are relatively fixed in position, the relative position relationship between the first line image 111 and the second line image 212 (as shown in FIG. 3A to 3C) is fixed. With the stage 40 moving along the scanning direction, it can be seen that the first line image 111 gradually captures the image of the object to be tested 90 (i.e., the object to be tested image 113 in the oblique line portion), and the image of the object to be tested 90 in the plane image 211 (i.e., the object to be tested image 213) gradually shifts along the scanning direction. Here, for the sake of clarity, FIG. 2A to FIG. 2C depict the first line image 111 at an exaggerated scale, and in these figures, the plane image 211 is shown to be divided into 13 regions of the same size as the first line image 111. However, a person skilled in the art should understand that the line width of the first line image 111 may be only a few hundred nanometers or tens of micrometers.

Referring to FIGS. 3A to 3C , they are schematic diagrams of the first line image 111 and the plane image 211 shown in FIGS. 2A to 2C , respectively. It can be seen that the control module 60 can obtain another line image (hereinafter referred to as the second line image 212) in the area overlapping with the first line image 111 from the plane image 211. Since the optical paths of the first line image 111 and the second line image 212 overlap each other without position and angle deviation, the results can be compared based on the first line image 111 and the second line image 212, and the single point values with excessive variation can be removed; or a measurement adjustment method can be performed to correct the measurement results (for example, calculate the average value, calculate the standard deviation, etc.) to improve the measurement accuracy.

In some embodiments, as shown in FIG. 3B , the plane image 211 is divided into a leading region 214 and a trailing region 215 that do not overlap with the first line image 111 by the first line image 111. The control module 60 uses the image of the leading region 214 to pre-measure whether the image is overexposed or underexposed, so as to control the brightness of a portion of the linear light emitted by the linear scanning light module 10 accordingly. As shown in FIG. 3B , if the control module 60 detects that a certain area of the linear image in the leading region 214 is overexposed (for example, because a certain part of the material of the object to be measured 90 is easy to reflect light and causes overexposure), the linear image of the region is referred to as a third line image 216. When the linear light is projected onto the region, as shown in FIG. 3C , the control module 60 can control the brightness of a portion of the linear light emitted by the linear scanning light module 10 accordingly. Taking the LED array as an example, the light emitting brightness of the light emitting elements (ie, diode elements) corresponding to the overexposed area can be reduced so that the first line image 111 of FIG. 3C will not be overexposed.

In some embodiments, the control module 60 uses the image of the backward area 215 to verify the measurement results obtained by the above-mentioned result comparison or adjustment calculation. As shown in FIG3C, a certain line image area in the backward area 215 (the line image of this area is referred to as the fourth line image 217) can be used to verify the measurement results obtained by the adjustment calculation of the first line image 111 and the second line image 212 shown in FIG3B. It can also be used to determine whether the motion platform 50 is stable.

In some embodiments, the control module 60 calculates the height of the platform 40 according to the planar image 211. According to the height of the platform 40 measured at each time point, the motion variation of the motion platform 50 can be obtained and compensated.

In some embodiments, since a plane image 211 including the object to be measured 90 can be obtained after the surface scan, it is only necessary to perform the surface scan at the initial position of the line scan, and then no surface scan is performed at other positions of the line scan. However, the present invention does not limit the number of surface scans in this way. For example, after performing one or more line scans, a surface scan can be performed, and the process is repeated alternately. Alternatively, after performing a surface scan, one or more line scans can be performed, and the process is repeated alternately. In other words, the line scan or surface scan area can be configured according to the distribution characteristics of the object to be measured 90 to improve the scanning efficiency.

Several embodiments are described below to illustrate how to implement the optical path design so that the optical paths for obtaining the first line image 111 and the second line image 212 overlap each other without position and angle deviation.

Referring to FIG. 4 , it is a schematic diagram of the optical path of the stereoscopic image scanning device of the first embodiment of the present invention. The stereoscopic image scanning device is provided with an optical lens group (hereinafter referred to as the incident side optical lens group 72) and a beam splitter (hereinafter referred to as the incident side beam splitter 71) on the incident side optical path (or incident side optical path 70). The incident side optical lens group 72 is used to adjust the direction of light beam travel, magnification, focal length, etc., and can be, for example, a microscope objective lens or a double Gaussian mirror. The incident side beam splitter 71 is used to combine the linear light emitted by the linear scanning light module 10 and the plane light emitted by the plane scanning light module 20 into the same optical path. An optical lens group (hereinafter referred to as the reflective side optical lens group 82) and a spectroscopic element (hereinafter referred to as the reflective side spectroscopic element 81) are provided in the reflective side optical path (or reflective side optical path 80). The reflective side optical lens group 82 is used to adjust the direction of light beam travel, magnification, focal length, etc., and can be, for example, a microscope objective lens or a double Gaussian lens. The reflective side spectroscopic element 81 is used to separate the reflected linear light and the plane light from the same optical path. Here, the image capture module 30 includes a first camera unit 31 and a second camera unit 32, which are arranged after the reflective side spectroscopic element 81. After the reflected linear light passes through the reflective side spectrometer 81, it enters the first camera unit 31, and is captured as a first line image 111 by the first camera unit 31. After the reflected planar light passes through the reflective side spectrometer 81, it enters the second camera unit 32, and is captured as a planar image 211 by the second camera unit 32.

In some embodiments, the incident side spectroscopic element 71 and the reflection side spectroscopic element 81 are bandpass filters to allow light of a certain frequency band (wavelength) to pass through and light of another frequency band (wavelength) to be reflected. For example, the linear light is blue light and the plane light is red light, so that the linear light passes through the incident side spectroscopic element 71 and the reflection side spectroscopic element 81, and the plane light is reflected by the incident side spectroscopic element 71 and the reflection side spectroscopic element 81. In this way, the linear scanning light module 10 and the plane scanning light module 20 can switch freely or operate synchronously without interfering with each other.

In some embodiments, the bandpass filter allows light of a plurality of first frequency bands to pass through, and allows light of a plurality of second frequency bands that do not overlap with the first frequency band to be reflected. For example, light of the first frequency band in the red light band range can pass through, and light of the second frequency band in the red light band range can be reflected; light of the first frequency band in the green light band range can pass through, and light of the second frequency band in the green light band range can be reflected; light of the first frequency band in the blue light band range can pass through, and light of the second frequency band in the blue light band range can be reflected. In this way, the linear light is composed of at least one of the red light, green light, and blue light of the first frequency band; and the planar light is composed of at least one of the red light, green light, and blue light of the second frequency band. Alternatively, the surface light is composed of at least one of red light, green light, and blue light in the first frequency band; the linear light is composed of at least one of red light, green light, and blue light in the second frequency band. In this way, the linear scanning light module 10 and the plane scanning light module 20 can use specific color lights according to needs, and can switch freely or operate synchronously without interfering with each other.

In some embodiments, the incident side beam splitter 71 and the reflected side beam splitter 81 are polarizing beam splitters, and light of a certain polarization direction passes through the incident side beam splitter 71 and the reflected side beam splitter 81, and light of another polarization direction is reflected by the incident side beam splitter 71 and the reflected side beam splitter 81. Although not shown here, the linear light output by the linear scanning light module 10 first passes through a polarizer to form polarized light, and then passes to the incident side beam splitter 71. Similarly, the plane light output by the plane scanning light module 20 first passes through a polarizer to form polarized light of another direction, and then passes to the incident side beam splitter 71.

In some embodiments, the incident side spectroscopic element 71 and the reflected side spectroscopic element 81 are partial mirrors. In this example, the linear scanning light module 10 and the plane scanning light module 20 output linear light and plane light at different time points. In some embodiments, the line scan and the plane scan may be performed alternately in a cutting sequence. The finer the timing is cut, the effect of superimposing the line scan and the plane scan can be achieved. However, the present invention is not necessarily based on the cutting sequence, and it can also be divided into two time periods, with the first time period performing one of the line scan and the plane scan, and the second time period performing the other of the line scan and the plane scan.

Referring to FIG. 5 , it is a schematic diagram of the optical path of the stereoscopic image scanning device of the second embodiment of the present invention. In this example, the exemplary image capture module 30 can be implemented by a color camera unit 33. The color filter array (Color filter array), or Bayer filter, of the color camera of the color camera unit 33 is used to filter out linear light of a specific frequency band (wavelength) and plane light of another frequency band (wavelength), without the need to additionally set the aforementioned bandpass filter on the reflection side. The configuration of the color camera unit 33 and the incident side is the same as that of the first embodiment, and will not be repeated here.

Referring to FIG. 6 , it is a schematic diagram of the optical path of the stereoscopic image scanning device of the third embodiment of the present invention. In this example, the linear scanning light module 10 and the plane scanning light module 20 can be integrated into a digital microlens device 12. The digital microlens device 12 has a plurality of microlenses arranged in two dimensions (not shown in the figure), each of which can control a pixel in the projection screen, thereby controlling one or a few rows or one or a few lines of microlenses at a first time to reflect the light of a light source (such as a laser-formed linear light source) to output linear light, thereby controlling the line width of the linear light; and controlling the entire two-dimensional array of microlenses at a second time to reflect the light of another light source (such as a light-emitting diode matched with a focusing lens) to output plane light. The configuration of the reflective side is the same as that of the first embodiment, and will not be repeated here. The digital micromirror device 12 may have the above-mentioned two light sources (i.e., a laser light source with a smaller light-emitting area for outputting linear light and a light source with a larger light-emitting area for outputting planar light) built in, or receive light outputted by the two external light sources.

Referring to FIG. 7 , it is a schematic diagram of the optical path of the stereoscopic image scanning device of the fourth embodiment of the present invention. This is an example, and the incident side and the reflection side shown in the above-mentioned embodiments can be freely combined with each other. For example, this example illustrates the combination of the incident side configuration of the third embodiment and the reflection side configuration of the second embodiment.

Referring to FIG8 , it is a schematic diagram of the optical path of the stereoscopic image scanning device of the fifth embodiment of the present invention. Here, it is illustrated that the incident side optical lens set 72 may be two, respectively disposed between the linear scanning light module 10 and the incident side spectroscopic element 71 and between the plane scanning light module 20 and the incident side spectroscopic element 71. Similarly, the reflection side optical lens set 82 may be two, respectively disposed between the first camera unit 31 and the reflection side spectroscopic element 81 and between the second camera unit 32 and the reflection side spectroscopic element 81.

In some embodiments, the incident side optical lens set 72 and the reflection side optical lens set 82 use infinite conjugate microscope objective lenses. The linear scanning light module 10, the plane scanning light module 20, the first camera unit 31, the second camera unit 32, and the color camera unit 33 used in the embodiment are further provided with a field lens or other lens sets for imaging.

In some embodiments, for an application case of outputting linear light for line scanning and outputting plane light for surface scanning at different time points, after completing a complete line scan (i.e., completing the scan of the object to be measured 90 by line scanning), a surface scan is performed to obtain a line scan result and a surface scan result. Alternatively, a surface scan is performed first, and then a complete line scan is completed. After obtaining the line scan result and the surface scan result, the line scan result and the surface scan result are compared with each other, or corrected according to an adjustment algorithm to obtain a measurement result. In some embodiments, surface scanning may be performed only on a portion of the object to be tested 90 to compare or calibrate the scanning results of a specific portion, thereby speeding up the scanning speed.

In the embodiment of the present invention, the existing line scanning technology can be used to analyze the first line image, and the existing surface scanning technology (such as phase shift and spatial coding) can be used to analyze the plane image, which will not be described in detail here.

In summary, according to the stereoscopic image scanning device proposed in the embodiment of the present invention, the combined optical path not only optimizes the equipment volume and reduces the cost, but also further combines the advantages of line scanning and surface scanning, so that the scanning accuracy can be improved. In addition, the leading area 214 of the surface scan can be used to determine whether the light of the line scan needs to be reduced or compensated. In addition, the following area 215 of the surface scan can be used to verify the scanning calculation results. In addition, the surface scan can obtain the regional height to compensate for the motion variation caused by the motion platform 50 and improve the measurement accuracy.

10: Linear scanning light module 12: Digital microscope device 20: Planar scanning light module 30: Image capture module 31: First camera unit 32: Second camera unit 33: Color camera unit 40: Carrier 50: Motion platform 60: Control module 70: Incident side optical path 71: Incident side spectroscopic element 72: Incident side optical lens set 80: Reflection side optical path 81: Reflection side spectroscopic element 82: Reflection side optical lens set 90: Object to be tested 111: First line image 113: Object to be tested image 211: Planar image 212: Second line image 213: Object to be tested image 214: First area 215: Second area 216: Third line image 217: Fourth line image

FIG1 is a schematic diagram of the structure of a stereoscopic image scanning device of an embodiment of the present invention. FIG2A is a schematic diagram of a first line image and a plane image captured at time t1. FIG2B is a schematic diagram of a first line image and a plane image captured at time t2. FIG2C is a schematic diagram of a first line image and a plane image captured at time t3. FIG3A is a schematic diagram of a first line image and a plane image shown in FIG2A. FIG3B is a schematic diagram of a first line image and a plane image shown in FIG2B. FIG3C is a schematic diagram of a first line image and a plane image shown in FIG2C. FIG4 is a schematic diagram of the optical path of a stereoscopic image scanning device of the first embodiment of the present invention. FIG5 is a schematic diagram of the optical path of a stereoscopic image scanning device of the second embodiment of the present invention. FIG6 is a schematic diagram of the optical path of the stereoscopic image scanning device of the third embodiment of the present invention. FIG7 is a schematic diagram of the optical path of the stereoscopic image scanning device of the fourth embodiment of the present invention. FIG8 is a schematic diagram of the optical path of the stereoscopic image scanning device of the fifth embodiment of the present invention.

10: Linear scanning light module 20: Planar scanning light module 30: Image acquisition module 40: Carrier 50: Motion platform 60: Control module 90: Object to be tested 111: First-line image 211: Planar image

Claims (12)

A stereoscopic image scanning device includes: a linear scanning light module for projecting a linear light onto an object to be measured along an incident angle; a plane scanning light module for projecting a plane light onto the object to be measured along the same incident angle; an image capture module for capturing the linear light and the plane light reflected by the object to be measured, thereby obtaining a first line image and a plane image; a motion platform for controlling the relative movement between the object to be measured, the linear scanning light module, the plane scanning light module and the image capture module, so as to scan the object to be measured along a scanning direction; and a control module for coupling and controlling the linear scanning light module, the plane scanning light module, the image capture module and the motion platform. The stereoscopic image scanning device as described in claim 1, wherein the control module obtains a second line image of the overlapping area with the first line image from the plane image, and compares the first line image and the second line image or corrects them according to an adjustment algorithm to obtain a measurement result. A stereoscopic image scanning device as described in claim 1, wherein the plane image is divided into a leading area that does not overlap with the first line image by the first line image, and the control module uses the image of the leading area to pre-measure whether the image is overexposed, so as to control the brightness of a part of the linear light emitted by the linear scanning light module accordingly. A stereoscopic image scanning device as described in claim 1, wherein the plane image is divided by the first line image into a backward area that does not overlap with the first line image, and the control module uses the image of the backward area to verify a measurement result. The stereoscopic image scanning device as described in claim 1 further includes a carrier for carrying the object to be measured, wherein the control module calculates the height of the carrier according to the planar image, thereby obtaining the motion variation caused by the motion platform. The stereoscopic image scanning device as described in claim 1 further includes a beam splitter to combine the linear light and the plane light into the same optical path. The stereoscopic image scanning device as described in claim 1 further includes a beam splitter element to separate the reflected linear light and the plane light from the same optical path, wherein the image capture module includes a first camera unit and a second camera unit, which are arranged after the beam splitter element to respectively receive the reflected linear light and the plane light separated from the same optical path. A stereoscopic image scanning device as described in claim 6 or 7, wherein the beam splitter is a bandpass filter. A stereoscopic image scanning device as described in claim 6 or 7, wherein the beam splitting element is a polarizing beam splitter. A stereoscopic image scanning device as described in claim 6 or 7, wherein the beam splitting element is a half-reflecting mirror. In the stereoscopic image scanning device described in claim 1, the linear scanning light module and the planar scanning light module are integrated into a digital micromirror device. The stereoscopic image scanning device as described in claim 1 further includes a bandpass filter to merge the linear light and the plane light into the same optical path. The image capture module is a color photography unit, and a color filter matrix of the color photography unit is used to separate the reflected linear light and the plane light from the same optical path.

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