Pattern projection system and area array scanning equipment

Abstract

The utility model discloses a pattern projection system and area array scanning equipment. The pattern projection system provided by the embodiment of the utility model is used for generating a plurality of characteristic patterns of light beams with different wave bands and projecting the characteristic patterns at the same working distance. According to the pattern projection system and the area array scanning equipment, the pattern projection system can generate the characteristic patterns of the light beams of various different wavebands and project the characteristic patterns at the same working distance, so that the various different wavebands can adapt to the to-be-measured objects of different materials, and the application range of the area array scanning equipment for scanning the objects is greatly expanded.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of area array scanning, in particular to a pattern projection system and an area array scanning device. BACKGROUND

[0002] As an advanced measuring device, area array scanners have been widely used in many fields, such as industrial detection, reverse engineering, medical diagnosis, etc. The pattern projection system is one of the cores of the area array scanner, and its main function is to project a specific structured light pattern onto the object to be measured. This process is the basis for subsequent image acquisition and three-dimensional reconstruction. At present, most of the pattern projection systems on the market use single-color Light Emitting Diode (LED) light sources combined with Digital Light Processing (DLP) display technology projection light machines. However, single-color projection light machines are difficult to adapt to different materials of the object to be measured due to the use of single-color wavelengths. CONTENT OF THE UTILITY MODEL

[0003] The present application provides a pattern projection system and an area array scanning device to solve at least one of the above technical problems.

[0004] The pattern projection system of the present application is used to generate characteristic patterns of multiple different waveband light beams and project them at the same working distance.

[0005] In some embodiments, the pattern projection system includes a multi-waveband pattern projection unit, and each multi-waveband pattern projection unit is used to generate characteristic patterns of multiple different waveband light beams and project them at the same working distance.

[0006] The pattern projection system includes multiple single-waveband pattern projection units, and each single-waveband pattern projection unit is used to generate characteristic patterns of a waveband light beam and project them at the same working distance.

[0007] In some embodiments, the multi-waveband pattern projection unit includes a multi-waveband projection light engine and a projection lens, the multi-waveband projection light engine is used to generate characteristic patterns of multiple different waveband light beams, and the projection lens is used to project the characteristic patterns of multiple different waveband light beams at the same working distance.

[0008] In some embodiments, the multi-waveband projection light engine includes multiple light sources, a beam combining system, and a modulation system, and the modulation system includes a display panel.

[0009] The multiple light sources are respectively used to emit multiple different waveband light beams.

[0010] The beam combining system is used to combine the light paths corresponding to the multiple light sources.

[0011] The modulation system is configured to control the working state of the display panel according to the input picture information, so as to generate the characteristic pattern of the light beams of different wavebands.

[0012] In some embodiments, the multi-waveband projection light engine comprises a display panel configured to generate the characteristic pattern of the light beams of different wavebands.

[0013] In some embodiments, the light source types of the plurality of light sources are any one or more of LED, halogen lamp, VCSEL, and laser bank.

[0014] In some embodiments, the multi-waveband projection light engine further comprises at least one angle variation system arranged between at least one light source and the beam combination system, the at least one angle variation system being configured to adjust the divergence angle of the light beam emitted by the at least one light source, so that the divergence angles of the light beams emitted by the plurality of light sources are close to each other after passing through the at least one angle variation system.

[0015] In some embodiments, the at least one angle variation system is a collimation system and / or an angle expansion system.

[0016] In some embodiments, the multi-waveband projection light engine further comprises a light homogenization system arranged between the beam combination system and the modulation system, the light homogenization system being configured to shape the light beam into a light spot with uniform light intensity distribution.

[0017] In some embodiments, the multi-waveband projection light engine further comprises a relay system arranged between the beam combination system and the modulation system, the relay system being configured to perform scaling processing on the light spot size.

[0018] In some embodiments, the display panel is any one of DMD, LCoS, and microLED.

[0019] In some embodiments, the modulation system further comprises a light splitting system, the modulation system being configured to control the working state of the display panel according to the input picture information, so that the light beam in bright state is incident on the projection lens through the light splitting system, and the light beam in dark state is returned through the light splitting system.

[0020] In some embodiments, when the display panel is DMD, the light splitting system is a TIR prism or an RTIR prism.

[0021] In some embodiments, when the display panel is LCoS, the light splitting system is a PBS prism.

[0022] The area array scanning device of some embodiments of the present application comprises the pattern projection system and the image acquisition system of any of the above embodiments, the pattern projection system is used to project the characteristic pattern of the multiple different waveband light beams to the object to be measured at the same working distance, and the image acquisition system is used to acquire the characteristic pattern modulated by the object to be measured to obtain a characteristic image.

[0023] In some embodiments, the image acquisition system comprises an imaging lens and a camera, the imaging lens is used to image the characteristic pattern of the multiple different waveband light beams to the camera.

[0024] In the pattern projection system and the area array scanning device of some embodiments of the present application, the pattern projection system can generate the characteristic pattern of the multiple different waveband light beams and project it to the same working distance, so that the multiple different wavebands can adapt to the object to be measured of different materials, greatly increasing the application range of the area array scanning device in scanning the object.

[0025] Additional aspects and advantages of the present application will be in part apparent and in part pointed out hereinafter. BRIEF DESCRIPTION OF DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the related art, the drawings needed to be used in the embodiments or the related art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained from the structures shown in the drawings without creative labor for those skilled in the art. Among them:

[0027] Figure 1 is a module schematic diagram of the area array scanning device of some embodiments of the present application;

[0028] Figure 2 is one of the module schematic diagrams of the pattern projection system of some embodiments of the present application;

[0029] Figure 3 is the second module schematic diagram of the pattern projection system of some embodiments of the present application;

[0030] Figure 4 is a module schematic diagram of the multi-waveband pattern projection unit of some embodiments of the present application;

[0031] Figure 5 is a schematic diagram of two flip states of the reflecting mirror in the display panel of some embodiments of the present application;

[0032] Figure 6 is a schematic diagram of the bright state light path of the DMD combined with the TIR prism of some embodiments of the present application;

[0033] Figure 7 is a schematic diagram of the dark state light path of a DMD with a TIR prism according to some embodiments of the present application;

[0034] Figure 8 is a schematic diagram of the bright state light path of a LCoS with a PBS prism according to some embodiments of the present application;

[0035] Figure 9 is a schematic diagram of the modules of an image acquisition system according to some embodiments of the present application;

[0036] Figure 10 is a schematic diagram of one of the structures of a multi-band pattern projection unit according to some embodiments of the present application;

[0037] Figure 11 is a schematic diagram of the other of the structures of a multi-band pattern projection unit according to some embodiments of the present application.

[0038] BRIEF DESCRIPTION OF DRAWINGS

[0039] pattern projection system 100, multi-band pattern projection unit 101, single-band pattern projection unit 102, multi-band projection light engine 10, light source 11, first light source 111, second light source 112, third light source 113, beam combining system 12, modulation system 13, display panel 131, mirror 1311, beam splitting system 132, angle changing system 14, collimating system 141, angle expanding system 142, homogenizing system 15, relay system 16, projection lens 20, image acquisition system 200, imaging lens 201, camera 202, synchronous triggering system 300, computing system 400, area array scanning device 1000. DETAILED DESCRIPTION

[0040] Embodiments of the present application are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals are used throughout to denote the same or similar elements or elements having the same or similar functions. The embodiments described below by reference to the drawings are examples only, and are used only for the purpose of explanation of the present application, and are not to be understood as limiting the present application.

[0041] Referring to Figures 1 to 3 , the pattern projection system 100 according to embodiments of the present application is used to generate characteristic patterns of light beams of multiple different bands and project them to the same working distance.

[0042] In the pattern projection system 100 according to embodiments of the present application, the pattern projection system 100 can generate characteristic patterns of light beams of multiple different bands and project them to the same working distance, so that the multiple different bands can adapt to objects to be measured of different materials, greatly increasing the application range of the area array scanning device 1000 in scanning objects.

[0043] In particular, the feature pattern is, for example, a structured light pattern. The form of the feature pattern includes, but is not limited to, speckle, stripe, Gray code, etc. The pattern projection system 100 is configured to generate feature patterns of multiple different waveband light beams and project the feature patterns to the same working distance. The same working distance can refer to a single working distance or a range of working distances. The feature patterns of the multiple different waveband light beams are projected to the same working distance. In the embodiments of the present application, multiple refers to two or more, and the same applies to a plurality, which refers to two or more, and thus is not described herein.

[0044] In some embodiments, the pattern projection system 100 can have multiple scanning modes. When the area array scanning device 1000 scans objects of different materials, different scanning modes can be selected according to the specific material to generate feature patterns of different waveband light beams and project the feature patterns to the same working distance. For example, when scanning silver background products (such as sheet metal, vehicle workpieces, etc.), metal printed products on a thin film, the blue waveband light beam has better reflection effect, and the pattern projection system 100 can work in a blue scanning mode to generate a feature pattern of a blue waveband light beam and project the feature pattern to the same working distance. When performing transparent soft board hole positioning on a black substrate, green circuit board line detection, and transparent film thickness detection, the red waveband light beam can improve the contrast, and the pattern projection system 100 can work in a red scanning mode to generate a feature pattern of a red waveband light beam and project the feature pattern to the same working distance. When scanning red background products and silver background products (such as sheet metal, vehicle workpieces, etc.), the pattern projection system 100 can work in a green scanning mode to generate a feature pattern of a green waveband light beam and project the feature pattern to the same working distance. When performing general LCD screen detection, photovoltaic silicon wafer detection, semiconductor wafer detection, new energy battery detection, and video monitoring, the infrared waveband light beam has stronger transmission, and the pattern projection system 100 can work in an infrared scanning mode to generate a feature pattern of an infrared waveband light beam and project the feature pattern to the same working distance. In this way, the scanning waveband is selected according to the material of the object to be scanned, which not only reduces the light power of the waveband projected by the pattern projection system 100, but also reduces the exposure time of the camera 202 (as shown in FIG. 2) in the image acquisition system 200, thereby improving the scanning speed of the area array scanning device 1000. Figure 9

[0045] Of course, the pattern projection system 100 can also be used to generate feature patterns of more different waveband light beams and project the feature patterns to the same working distance. At this time, the pattern projection system 100 can have more scanning modes, which are not described herein.

[0046] The pattern projection system 100 of the embodiments of the present application can include a multi-waveband pattern projection unit 101 or be composed of multiple single-waveband pattern projection units 102.

[0047] Please refer to​Figure 2 In some embodiments, the pattern projection system 100 comprises a multi-band pattern projection unit 101. The multi-band pattern projection unit 101 is configured to generate feature patterns of multiple different wavelength beams and project the feature patterns to the same working distance.

[0048] Specifically, taking an example that the multi-band pattern projection unit 101 is configured to generate feature patterns of two different wavelength beams and project the feature patterns to the same working distance. The multi-band pattern projection unit 101 is configured to generate feature patterns of a first wavelength beam and project the feature patterns to the same working distance, and is configured to generate feature patterns of a second wavelength beam and project the feature patterns to the same working distance. The wavelength of the first wavelength beam is smaller than the wavelength of the second wavelength beam, or the wavelength of the first wavelength beam is larger than the wavelength of the second wavelength beam.

[0049] The embodiments of the present application utilize the multi-band pattern projection unit 101 to generate feature patterns of multiple different wavelength beams and project the feature patterns to the same working distance, which is compact in structure and is conducive to miniaturization of the pattern projection system 100, and meanwhile, the utilization rate of elements is high.

[0050] Please refer to Figure 3 In some embodiments, the pattern projection system 100 comprises multiple single-band pattern projection units 102. Each single-band pattern projection unit 102 is configured to generate feature patterns of a wavelength beam and project the feature patterns to the same working distance.

[0051] Specifically, taking an example that the pattern projection system 100 comprises two single-band pattern projection units 102. The first single-band pattern projection unit 102 is configured to generate feature patterns of a first wavelength beam and project the feature patterns to the same working distance, and the second single-band pattern projection unit 102 is configured to generate feature patterns of a second wavelength beam and project the feature patterns to the same working distance. The wavelength of the first wavelength beam is smaller than the wavelength of the second wavelength beam, or the wavelength of the first wavelength beam is larger than the wavelength of the second wavelength beam.

[0052] The embodiments of the present application utilize the multiple single-band pattern projection units 102 to generate feature patterns of multiple different wavelength beams and project the feature patterns to the same working distance, which is simple in structure, easy to maintain and calibrate, and each single-band pattern projection unit 102 generates feature patterns with stable wavelength.

[0053] Please refer to Figure 4 In some embodiments, the multi-band pattern projection unit 101 comprises a multi-band projection light engine 10 and a projection lens 20. The multi-band projection light engine 10 is configured to generate feature patterns of multiple different wavelength beams, and the projection lens 20 is configured to project the feature patterns of the multiple different wavelength beams to the same working distance.

[0054] Specifically, the multi-band projection light engine 10 provides a plurality of monochromatic illumination light paths of different wavebands. The multi-band projection light engine 10 generates a plurality of characteristic patterns of different wavebands, which are incident to the projection lens 20 and projected by the projection lens 20 at the same working distance. It should be noted that the plurality of different wavebands are mainly to adapt to objects of different materials. For the plurality of characteristic patterns of different wavebands, the projection lens 20 projects them at the same working distance. Taking an example of the multi-band projection light engine 10 being used to generate characteristic patterns of two different wavebands, the projection lens 20 is used to project the characteristic patterns of the two different wavebands at the same working distance.

[0055] Referring to Figure 4 and Figure 5 In some embodiments, the multi-band projection light engine 10 includes a plurality of light sources 11, a beam combining system 12, and a modulation system 13. The modulation system 13 includes a display panel 131. The plurality of light sources 11 are respectively used to emit light beams of a plurality of different wavebands. The beam combining system 12 is used to combine the light paths corresponding to the plurality of light sources 11. The modulation system 13 is used to control the working state of the display panel 131 according to input picture information, so as to generate characteristic patterns of a plurality of different wavebands.

[0056] Specifically, along the direction of the exit light path of the multi-band pattern projection unit 101, there are the light sources 11, the beam combining system 12, the modulation system 13, and the projection lens 20 in sequence.

[0057] Taking an example of the plurality of light sources 11 including a first light source 111 and a second light source 112, the first light source 111 and the second light source 112 are respectively used to emit light beams of different wavebands. For example, the first light source 111 is used to emit a 450 nm waveband light beam, and the second light source 112 is used to emit an 850 nm waveband light beam; for another example, the first light source 111 is used to emit an 810 nm waveband light beam, and the second light source 112 is used to emit a 455 nm waveband light beam.

[0058] The beam combining system 12 is used to combine the light paths corresponding to the plurality of light sources 11, so that the plurality of light sources 11 can share the modulation system 13, the projection lens 20, and the subsequent uniform light system 15, relay system 16, etc. According to the different number of the plurality of light sources 11, the beam combining system 12 can adopt different beam combining elements.

[0059] For example, when the plurality of light sources 11 includes the first light source 111 and the second light source 112, the beam combining system 12 can be a dichroic mirror. By coating a lens plate, light beams of different wavebands can be transmitted or reflected through the lens plate, so as to achieve the beam combining effect. For example, the light beams of the first waveband are transmitted through the lens plate, while the light beams of the second waveband are reflected through the lens plate, so as to combine the light paths corresponding to the first light source 111 and the second light source 112.

[0060] For example, when the plurality of light sources 11 include a first light source 111, a second light source 112 and a third light source 113 (as shown in FIG. 1C), the beam combining system 12 can be an X-prism or an X-cube or two parallel dichroic mirrors. Among them, the X-prism is two perpendicular dichroic mirrors, and the X-cube is made of four isosceles right triangles, and the bonding surface is the film-coated surface. Similarly, when the plurality of light sources 11 include four or more light sources 11, the beam combining system 12 can be composed of more dichroic mirrors, which will not be illustrated one by one here. Figure 10

[0061] The modulation system 13 is used to control the working state of the display panel 131 according to the input picture information, so as to generate a characteristic pattern. Controlling the working state of the display panel 131 specifically refers to controlling the working state of each pixel unit in the display panel 131, and the working state includes projection or non-projection. When a certain pixel unit does not project, it is in a "dark state"; when a certain pixel unit projects, it is in a "bright state". The modulation system 13 can project the bright state light beam to the region of interest through the projection lens 20, and return the dark state light beam to the original light path, so that the light beam is not projected through the projection lens 20 any more, so as to realize the beam splitting of the bright state light beam and the dark state light beam and control whether to project through the projection lens 20. The modulation system 13 controls the working state of the display panel 131 according to the picture information, and can generate a corresponding characteristic pattern.

[0062] Please refer to Figure 4 In some embodiments, the light source type of the plurality of light sources 11 is any one or more of a light emitting diode (LED), a halogen lamp, a vertical-cavity surface-emitting laser (VCSEL) and a laser bank.

[0063] Specifically, taking the plurality of light sources 11 including the first light source 111 and the second light source 112 as an example, the light source type of the first light source 111 and the second light source 112 can be both LED; or the light source type of the first light source 111 and the second light source 112 is both VCSEL; or the light source type of the first light source 111 is LED and the light source type of the second light source 112 is halogen lamp; or the light source type of the first light source 111 is VCSEL and the light source type of the second light source 112 is laser bank, etc., which will not be illustrated one by one here.

[0064] It should be noted that no matter whether the light source type of the plurality of light sources 11 is one or a combination of multiple types described above, the plurality of light sources 11 need to meet the requirements of emitting light beams of multiple different wavebands respectively.

[0065] Please refer to Figure 4 ​In some embodiments, the multi-band projection light engine 10 further comprises at least one angle changing system 14 arranged between the at least one light source 11 and the beam combining system 12. The at least one angle changing system 14 is configured to adjust the divergence angle of the light beams emitted by the at least one light source 11 so that the divergence angles of the light beams emitted by the plurality of light sources 11 are close to each other after passing through the at least one angle changing system 14.

[0066] Specifically, the angle changing system 14 is arranged between the light source 11 and the beam combining system 12. In the direction of the exit light path of the multi-band pattern projection unit 101, the light source 11, the angle changing system 14, the beam combining system 12, the modulation system 13 and the projection lens 20 are arranged in sequence. The angle changing system 14 can be composed of a lens or a lens group.

[0067] In some embodiments, the number of the angle changing systems 14 can be equal to the number of the light sources 11. In this case, the angle changing system 14 is arranged between each light source 11 and the beam combining system 12, and each angle changing system 14 is configured to adjust the divergence angle of the light beams emitted by the corresponding light source 11 so that the divergence angles of the light beams emitted by all the light sources 11 are close to each other after passing through the corresponding angle changing system 14. Taking the example that the plurality of light sources 11 comprises a first light source 111 and a second light source 112, the divergence angle of the light beams emitted by the first light source 111 is 15 degrees, and the divergence angle of the light beams emitted by the second light source 112 is 5 degrees. The angle changing system 14 is arranged between the first light source 111 and the beam combining system 12 and between the second light source 112 and the beam combining system 12. After passing through the two angle changing systems 14, the divergence angles of the light beams emitted by the first light source 111 and the second light source 112 are both 10 degrees.

[0068] In some other embodiments, the number of the angle changing systems 14 can be less than the number of the light sources 11. In this case, the angle changing system 14 is arranged between some light sources 11 and the beam combining system 12, and each angle changing system 14 is configured to adjust the divergence angle of the light beams emitted by the corresponding light source 11 so that the divergence angles of the light beams emitted by all the light sources 11 are close to each other after passing through the corresponding angle changing system 14. Taking the example that the plurality of light sources 11 comprises a first light source 111 and a second light source 112, the divergence angle of the light beams emitted by the first light source 111 is 15 degrees, and the divergence angle of the light beams emitted by the second light source 112 is 10 degrees. The angle changing system 14 is arranged between the first light source 111 and the beam combining system 12. After passing through the angle changing system 14, the divergence angles of the light beams emitted by the first light source 111 and the second light source 112 are both 10 degrees.

[0069] It should be noted that, in the embodiments of the present application, the "close to each other" can mean that the difference between the divergence angles is less than a predetermined angle. Taking the example that the predetermined angle is 1 degree, when the difference between the divergence angles of the light beams emitted by the plurality of light sources 11 after passing through the at least one angle changing system 14 is less than 1 degree, it can be considered that the divergence angles are close to each other. Preferably, the "close to each other" means that the divergence angles are equal.

[0070] In other embodiments, the multi-band projection light engine 10 can also not include the angle conversion system 14, without limitation.

[0071] Referring to Figure 4 and Figure 11 In some embodiments, the at least one angle conversion system 14 is a collimation system 141 and / or an expansion system 142.

[0072] Specifically, the collimation system 141 is configured to collimate a large divergence angle of a light beam to a small divergence angle. The expansion system 142 is configured to expand a small divergence angle of a light beam to a large divergence angle.

[0073] For example, if the divergence angle of the light beam emitted by the first light source 111 is 15 degrees and the divergence angle of the light beam emitted by the second light source 112 is 10 degrees, a collimation system 141 can be arranged between the first light source 111 and the beam combination system 12 to collimate the divergence angle of the light beam emitted by the first light source 111 from 15 degrees to 10 degrees; or an expansion system 142 can be arranged between the second light source 112 and the beam combination system 12 to expand the divergence angle of the light beam emitted by the second light source 112 from 10 degrees to 15 degrees.

[0074] Referring to Figure 4 In some embodiments, the multi-band projection light engine 10 further includes an integrator system 15 arranged between the beam combination system 12 and the modulation system 13. The integrator system 15 is configured to shape the light beam into a light spot with uniform light intensity distribution.

[0075] Specifically, the integrator system 15 is arranged between the beam combination system 12 and the modulation system 13. In the direction of the exit light path of the multi-band pattern projection unit 101, the light source 11, the beam combination system 12, the integrator system 15, the modulation system 13, and the projection lens 20 are arranged in sequence.

[0076] The integrator system 15 is configured to shape the light beam incident from the beam combination system 12 into a light spot with uniform light intensity distribution, and the shape of the light spot is, for example, rectangular. The integrator system 15 can use an integrator device such as an ommatidium or a light bar. The working principle of the ommatidium is to divide the incident light beam into multiple small light sources and then integrate and superimpose the multiple small light sources into a light spot with uniform light intensity distribution. The working principle of the light bar is that the light beam is reflected multiple times in the light bar, each reflection forms a virtual light source, and multiple reflections form a two-dimensional virtual light source matrix, thereby making the exit light spot more uniform.

[0077] The integrator device used as the integrator system 15 can be selected according to actual needs in the embodiments of the present application. In addition, in other embodiments, the integrator system 15 can also not be arranged, without limitation.

[0078] Referring to Figure 4In some embodiments, the multi-band projection light engine 10 further comprises a relay system 16 disposed between the beam combining system 12 and the modulation system 13. The relay system 16 is used to scale the spot size.

[0079] Specifically, the relay system 16 is disposed between the beam combining system 12 and the modulation system 13. Along the direction of the outgoing light path of the multi-band pattern projection unit 101, there are the light source 11, the beam combining system 12, the relay system 16, the modulation system 13, and the projection lens 20 in sequence. The relay system 16 is used to scale the spot size to the required size for projection to the display panel 131.

[0080] Please refer to Figure 4 and Figure 5 When the multi-band projection light engine 10 simultaneously comprises multiple light sources 11, at least one angle conversion system 14, a beam combining system 12, a uniform light system 15, a relay system 16, and a modulation system 13, along the direction of the outgoing light path of the multi-band pattern projection unit 101, there are the light source 11, the angle conversion system 14, the beam combining system 12, the uniform light system 15, the relay system 16, the modulation system 13, and the projection lens 20 in sequence. The working process is as follows: the multiple light sources 11 respectively emit multiple light beams of different wavelengths, the divergence angles of the light beams are adjusted to the required angles by the respective angle conversion systems 14, the light paths corresponding to the multiple light sources 11 are combined by the beam combining system 12, the light beams are shaped into uniform light spots by the uniform light system 15, the spot size is scaled to the required size by the relay system 16 for projection to the display panel 131, and the working state of the display panel 131 is controlled by the modulation system 13 according to the input picture information, so that the bright-state light beams are projected to the region of interest by the projection lens 20, and the dark-state light beams are returned to the original light path and no longer pass through the projection lens 20 for projection.

[0081] It should be noted that the multi-band projection light engine 10 can be composed of part or all of the above-mentioned elements according to the actual use scene.

[0082] Please refer to Figure 5 In some embodiments, the display panel 131 is any one of a digital micromirror device (DMD), a liquid crystal on silicon (LCoS), and a micro light emitting diode (micro LED).

[0083] Specifically, the DMD has the advantages of fast switching response speed, high display resolution, good brightness, high contrast, high stability, etc. The LCoS has the advantages of high resolution, high light efficiency, etc. The micro LED has the advantages of small size, low power consumption, high light efficiency, uniform and stable light emission, long service life, etc. In actual applications, a suitable type of display panel 131 can be selected according to specific needs.

[0084] Please refer to FIG. 4, Figures 5 to 7 In some embodiments, the modulation system 13 further includes a light splitting system 132. The modulation system 13 is configured to control the working state of the display panel 131 according to the input picture information, so that the bright-state light beam is incident on the projection lens 20 through the light splitting system 132, and the dark-state light beam is returned through the light splitting system 132.

[0085] In the embodiments of the present application, different types of display panels 131 can be used with different light splitting systems 132. By controlling the working state of the display panel 131, the bright-state light beam can be incident on the projection lens 20 through the light splitting system 132, and the dark-state light beam can be returned through the light splitting system 132. Of course, in other embodiments, the display panel 131 can also be used without the light splitting system 132, which is not limited herein.

[0086] Please refer to Figure 5 and Figure 6 In some embodiments, when the display panel 131 is a DMD, the light splitting system 132 is a TIR prism or an RTIR prism.

[0087] Specifically, the DMD includes millions of micro mirrors 1311, each of which has two flipping states, i.e., an on state and an off state, as shown in Figure 5 The two flipping states correspond to two different flipping angles in different directions. The specific values of the flipping angles can be equal.

[0088] The DMD can be used with a TIR prism or an RTIR prism. As shown in Figure 6 The bright-state light path of the DMD with a TIR prism is as follows: the incident light beam passes through the TIR prism and reaches the mirror 1311. Since the mirror 1311 is in the on state, the mirror 1311 reflects the light beam to the TIR prism, and the light beam is emitted through the projection lens 20. As shown in Figure 7 The dark-state light path of the DMD with a TIR prism is as follows: the incident light beam passes through the TIR prism and reaches the mirror 1311. Since the mirror 1311 is in the off state, the mirror 1311 reflects the light beam to the TIR prism, and the light beam returns along the original path and fails to be emitted through the projection lens 20. It should be noted that, Figure 6 and Figure 7The middle mirror 1311 has different flip angles in different directions, but since the size of the mirror 1311 is small, usually in the micron level, it does not appear significantly.

[0089] Please refer to Figure 8 In some embodiments, when the display panel 131 is an LCoS, the light splitting system 132 is a polarizing beam splitter (PBS).

[0090] Specifically, the LCoS includes a liquid crystal layer that modulates light by applying an external voltage to the pixels of the liquid crystal layer. The LCoS can be used with a PBS. The PBS is made of two right-angle triangular prisms glued together, one of which is coated with a polarizing beam splitter film on the glued side. When P-polarized light (horizontally polarized light) is incident on the PBS, it will pass directly through, while S-polarized light (vertically polarized light) will be reflected, thereby achieving separation of P-polarized light and S-polarized light.

[0091] When the external voltage to the pixels of the liquid crystal layer is 0, the incident S-polarized light passes through the liquid crystal layer without deflection of the polarization direction, and after being reflected from the bottom of the LCoS, it is reflected by the PBS, returning to the original light path and not passing through the projection lens 20 to be projected, the pixel light output is zero, i.e., the "dark state" is presented. As shown in Figure 8 When the external voltage to the pixels of the liquid crystal layer is not zero, the incident S-polarized light passes through the liquid crystal layer with deflection of the polarization direction, and the light reflected from the bottom of the LCoS is P-polarized light, which directly passes through the PBS and is projected by the projection lens 20, the pixel presents the "bright state" and forms an image in the region of interest.

[0092] In some embodiments, the multi-band projection light engine 10 includes a display panel 131. The display panel 131 is used to generate characteristic patterns of multiple different wavelength beams.

[0093] The embodiments of the present application can generate characteristic patterns of multiple different wavelength beams using the display panel 131 and the projection lens 20, and project them at the same working distance. Specifically, the display panel 131 is used to generate characteristic patterns of multiple different wavelength beams, and the projection lens 20 is used to project the characteristic patterns of multiple different wavelength beams at the same working distance. At this time, the display panel 131 can be a microLED, which can directly generate characteristic patterns of multiple different wavelength beams without the need for elements such as the light source 11, the angle-changing system 14, the beam-combining system 12, the light-uniformizing system 15, the relay system 16, and the modulation system 13.

[0094] Please refer to Figure 1The area array scanning device 1000 in the embodiments of the present application comprises the pattern projection system 100 and the image acquisition system 200 in any of the above embodiments. The pattern projection system 100 is configured to project the characteristic patterns of the light beams of multiple different wavebands to the object to be measured at the same working distance. The image acquisition system 200 is configured to acquire the characteristic patterns modulated by the object to be measured to obtain the characteristic images. The characteristic patterns modulated by the object to be measured refer to the deformation patterns caused by the surface of the object to be measured.

[0095] Specifically, the area array scanning device 1000 can be an area array scanner or the like. When the area array scanning device 1000 scans objects to be measured of different materials, different scanning modes can be selected according to the specific material to switch the wavebands of the light beams, generate the characteristic patterns of the light beams of different wavebands, and project the characteristic patterns of the light beams of different wavebands at the same working distance. In this way, the scanning wavebands of the objects to be measured of different materials are selected accordingly, which not only reduces the optical power of the wavebands projected by the pattern projection system 100, but also reduces the exposure time of the camera 202 in the image acquisition system 200, thereby improving the scanning speed of the area array scanning device 1000.

[0096] Referring to Figure 1 In some embodiments, the area array scanning device 1000 can further comprise a synchronous triggering system 300. The synchronous triggering system 300 is connected to the pattern projection system 100 and the image acquisition system 200 respectively. The synchronous triggering system 300 is configured to synchronously control the working states of the pattern projection system 100 and the image acquisition system 200. That is, the synchronous triggering system 300 controls the pattern projection system 100 to project the characteristic patterns to the object to be measured at the same time as controlling the image acquisition system 200 to acquire the characteristic patterns modulated by the object to be measured to obtain the characteristic images. In this way, the pattern projection system 100 and the image acquisition system 200 can work accurately and synchronously, avoid errors caused by asynchronization of the systems, and improve the scanning accuracy of the area array scanning device 1000.

[0097] Referring to Figure 1 In some embodiments, the area array scanning device 1000 can further comprise a computing system 400. After obtaining the characteristic images, the computing system 400 can reconstruct the three-dimensional information of the object to be measured by an algorithm. The reconstructed three-dimensional information can be applied to various fields such as industrial detection, virtual reality and augmented reality, and autonomous driving.

[0098] Referring to Figure 9 In some embodiments, the image acquisition system 200 comprises an imaging lens 201 and a camera 202. The imaging lens 201 is configured to image the characteristic patterns of the light beams of multiple different wavebands to the camera 202.

[0099] Specifically, the camera 202 can adopt an image sensor of a Charge Coupled Device (CCD) type or a Complementary Metal Oxide Semiconductor (CMOS) type, etc. The CCD image sensor has advantages of high resolution and low noise, while the CMOS image sensor has advantages of high integration, low power consumption, and high reading speed, etc. In actual applications, a suitable type of image sensor can be selected according to specific requirements.

[0100] With the multi-band projection light engine 10 for generating the characteristic patterns of two different wavebands, and the projection lens 20 for projecting the characteristic patterns of the two different wavebands to the same working distance as an example. The multi-band projection light engine 10 is used for generating the characteristic pattern of the first waveband, and the projection lens 20 is used for projecting the characteristic pattern of the first waveband to the same working distance, and the imaging lens 201 is used for imaging the characteristic pattern of the first waveband modulated by the object to be measured at the same working distance to the camera 202; the multi-band projection light engine 10 is used for generating the characteristic pattern of the second waveband, and the projection lens 20 is used for projecting the characteristic pattern of the second waveband to the same working distance, and the imaging lens 201 is used for imaging the characteristic pattern of the second waveband modulated by the object to be measured at the same working distance to the camera 202. In this way, the characteristic patterns of multiple different wavebands can be imaged to the camera 202 through the imaging lens 201.

[0101] The working processes of the pattern projection system 100 and the area array scanning device 1000 of the present application are described below in combination with specific embodiments.

[0102] Embodiment one:

[0103] Please refer to Figure 10 , the pattern projection system 100 uses monochromatic LEDs with main wavelengths of 450 nm, 550 nm and 640 mn wavebands, and collimates the light beams with a large angle of divergence into light beams with a divergence angle of about 10 degrees through a collimation system 141 composed of two lenses, and then combines the three light paths into one light path through a beam combination system 12 composed of an X-prism, and then forms a plurality of small rectangular light sources through an eye lens composed of an eye lens system 15, and then enters a modulation system 13 composed of a TIR prism and a DMD after scaling through a relay system 16, and the DMD controls the flipping state of the small mirrors 1311 inside according to the input picture information, and the light beams on the small mirrors 1311 in the bright state are totally reflected by the TIR prism, and then projected to the region of interest by the projection lens 20, and the light beams on the small mirrors 1311 in the dark state are returned to the original light path by the TIR prism, and then exit without passing through the projection lens 20.

[0104] When the area array scanning device 1000 scans different materials of the object to be measured, different scanning modes can be selected according to the specific material to generate a characteristic pattern of different waveband light beams and project on the same working distance. For example, when scanning silver background products (such as sheet metal, vehicle workpieces, etc.), thin film metal printed products, the reflection effect of the blue waveband light beam is better, and the pattern projection system 100 can work in the blue scanning mode to generate a characteristic pattern of the blue waveband light beam and project on the same working distance. When performing transparent soft plate hole positioning of a black substrate, green circuit board line detection, and light transmission film thickness detection, the red waveband light beam can improve the contrast, and the pattern projection system 100 can work in the red scanning mode to generate a characteristic pattern of the red waveband light beam and project on the same working distance. When scanning red background products and silver background products (such as sheet metal, vehicle workpieces, etc.), the pattern projection system 100 can work in the green scanning mode to generate a characteristic pattern of the green waveband light beam and project on the same working distance. When performing general LCD screen detection, photovoltaic silicon wafer detection, semiconductor wafer detection, new energy battery detection, and video monitoring, the infrared waveband light beam has stronger transmission (in actual application, the light beam is first transmitted to the inside of the object and then reflected out), and the pattern projection system 100 can work in the infrared scanning mode to generate a characteristic pattern of the infrared waveband light beam and project on the same working distance. In this way, the scanning waveband of the pattern projection system 100 is selected according to the material of the object to be measured, which not only reduces the light power of the waveband projected by the pattern projection system 100, but also reduces the exposure time of the camera 202 in the image acquisition system 200, thereby improving the scanning speed of the area array scanning device 1000.

[0105] Embodiment two:

[0106] Please refer to Figure 11 , the pattern projection system 100 uses a VCSEL with a main wavelength of 810 nm waveband and a laser bank with a main wavelength of 455 nm waveband. Both light sources 11 are polarized laser light sources, and the display panel 131 is an LCoS. The 810 nm waveband VCSEL is composed of 18 light-emitting small units with a light-emitting area of 1.5 mm, with an interval of 0.9 mm, arranged in 3 rows and 6 columns, and the beam divergence angle is about 23 degrees. The 455 nm waveband laser bank has a light-emitting area of 14 mm*18 mm, and the emitted angle is close to a collimated light beam with an angle of 0 degrees. The 810 nm waveband VCSEL is collimated by the collimation system 141 to about 10 degrees, and the 455 nm waveband laser bank is diverged by the angle expansion system 142 to about 10 degrees. The two light paths are combined into one light path through a dichroic mirror, and then pass through the light rod composed of the homogenization system 15 to form a uniformly distributed rectangular light spot, and then pass through the relay system 16 to scale to the required size, and then pass through the PBS to project on the LCoS.

[0107] The PBS is glued by two right-angle triangular prisms, one of which is glued with a polarization beam splitter film on the side, which can transmit P-polarized light and reflect S-polarized light, so as to realize the separation of P-polarized light and S-polarized light.

[0108] In order to improve the contrast of the projection system, a polarizer can be added between the LCoS and the PBS to improve the polarization of the LCoS projection light, so that more P-polarized light is transmitted by the PBS to the projection lens 20, and more S-polarized light is reflected back to the original light path by the PBS, so that the projected picture has a brighter bright state and a darker dark state.

[0109] The working principle of the area array scanning device 1000 in the second embodiment is basically the same as that in the first embodiment. The area array scanning device 1000 can switch the wavelength of the light beam according to the different materials of the scanned object, so as to select a more optimal scanning wavelength for the object to be measured of different materials. Not only the light power of the pattern projection system 100 can be reduced, but also the exposure time of the camera 202 in the image acquisition system 200 can be reduced, so as to improve the scanning speed of the area array scanning device 1000.

[0110] In summary, in the pattern projection system 100 and the area array scanning device 1000 of the embodiments of the present application, the pattern projection system 100 can generate characteristic patterns of multiple light beams of different wavelengths and project them at the same working distance. In this way, multiple wavelengths can adapt to objects to be measured of different materials, greatly increasing the application range of the area array scanning device 1000 for scanning objects.

[0111] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second" are only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first", "second" can explicitly or implicitly include one or more features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise specifically limited.

[0112] In the description of the application, it is necessary to point out that, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "linking" should be understood in a broad sense, for example, it can be fixed connection, or detachable connection, or integrally connected; it can be mechanical connection, or electrical connection; it can be direct connection, or indirect connection through intermediate medium, or internal communication of two elements or interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the application can be understood according to the specific circumstances.

[0113] In the present application, unless otherwise explicitly specified and limited, the "upper" or "lower" of the first feature to the second feature can include that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, the "upper", "above" and "on" of the first feature to the second feature includes that the first feature is directly above and obliquely above the second feature, or only indicates that the horizontal height of the first feature is higher than that of the second feature. The "under", "below" and "under" of the first feature to the second feature includes that the first feature is directly below and obliquely below the second feature, or only indicates that the horizontal height of the first feature is less than that of the second feature.

[0114] The above disclosure provides many different implementations or examples to implement the different structures of the present application. In order to simplify the disclosure of the present application, the components and arrangements of the specific examples are described in the above. Of course, they are only examples, and the purpose is not to limit the present application. In addition, the present application can repeatedly refer to the numbers and / or letters in different examples, and such repetition is for the purpose of simplification and clarity, which itself does not indicate the relationship between the various implementations and / or arrangements discussed. In addition, the present application provides various specific examples of processes and materials, but those skilled in the art can realize the application of other processes and / or the use of other materials.

[0115] In the description of the present application, the description of the terms "one embodiment", "some embodiments", "illustrative embodiment", "embodiment", "example", "specific example", "some examples" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present application, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0116] While the embodiments of the present application have been shown and described above, it will be apparent to those having ordinary skill in the art that a number of changes, modifications, alternatives, and variations can be made to the embodiments without departing from the principles and spirit of the application, the scope of which is defined by the claims and their equivalents.

Claims

1. A pattern projection system, characterized by, The pattern projection system comprises a multi-band pattern projection unit, the multi-band pattern projection unit comprises a multi-band projection light engine and a projection lens, the multi-band projection light engine is used to generate feature patterns of multiple different waveband light beams, and the projection lens is used to project the feature patterns of the multiple different waveband light beams to the same working distance; wherein: The multi-band projection light engine comprises a plurality of light sources, a beam combination system and a modulation system, and the modulation system comprises a display panel; The plurality of light sources are respectively used to emit light beams of multiple different wavebands; The beam combination system is used to combine the light paths corresponding to the plurality of light sources; The modulation system is used to control the working state of the display panel according to input picture information, so as to generate the feature patterns of the multiple different waveband light beams; Or The multi-band projection light engine comprises a display panel, and the display panel is used to generate the feature patterns of the multiple different waveband light beams.

2. The pattern projection system of claim 1, wherein The multi-band projection light engine further comprises at least one angle changing system arranged between at least one light source and the beam combination system, the at least one angle changing system is used to adjust the divergence angle of the light beam emitted by the at least one light source, so that the divergence angles of the light beams emitted by the plurality of light sources are close to each other after passing through the at least one angle changing system.

3. The pattern projection system of claim 1, wherein, The multi-band projection light engine further comprises an optical homogenization system arranged between the beam combination system and the modulation system, the optical homogenization system is used to shape the light beam into a light spot with uniform light intensity distribution.

4. The pattern projection system of claim 1, wherein, The multi-band projection light engine further comprises a relay system arranged between the beam combination system and the modulation system, and the relay system is used to perform scaling processing on the light spot size.

5. The pattern projection system of claim 1, wherein, The modulation system further comprises a light splitting system, and the modulation system is used to control the working state of the display panel according to input picture information, so that the light beam in the bright state is incident to the projection lens through the light splitting system, and the light beam in the dark state is returned through the light splitting system.

6. An area array scanning apparatus characterized by comprising: The pattern projection system comprises a multi-band pattern projection unit, the multi-band pattern projection unit comprises a multi-band projection light engine and a projection lens, the multi-band projection light engine is used to generate feature patterns of multiple different waveband light beams, and the projection lens is used to project the feature patterns of the multiple different waveband light beams to the same working distance; wherein:

7. The area array scanning apparatus according to claim 6, wherein The image acquisition system comprises an imaging lens and a camera, and the imaging lens is used to image the feature patterns of the multiple different waveband light beams to the camera.

Images