All-solid-state fringe projection device and 3D structured light measurement system

Abstract

The embodiment of the invention discloses an all-solid-state fringe projection device and a 3D structured light measurement system, and relates to the field of optical measurement. The all-solid-state fringe projection device comprises a light-emitting light source and an optical projection system, the light-emitting light source comprises a VCSEL array, the VCSEL array comprises a plurality of VCSEL line groups, each VCSEL line group comprises at least one VCSEL light-emitting hole, and each VCSEL light-emitting hole is used for emitting laser signals; the light-emitting light source is used for driving each VCSEL line group in the plurality of VCSEL arrays to open or close according to the pattern type, and emitting a laser signal based on all the opened VCSEL line groups; the optical projection system is used for carrying out collimation processing on the laser signal from the luminous light source, carrying out transverse modulation and longitudinal modulation on a light field of the laser signal, and projecting the processed laser signal to an object to be measured to form a stripe pattern; the provided all-solid-state fringe projection device has remarkable advantages in the aspects of reliability, light weight, miniaturization, signal-to-noise ratio, measurement accuracy, ambient light interference resistance, energy utilization efficiency, frame rate, cost and the like.

Description

Technical Field

[0001] The present application relates to the field of optical measurement, and in particular to a fully solid-state fringe projection device and a 3D structured light measurement system. Background Art

[0002] As a cutting-edge non-contact optical 3D measurement method, stripe structured light technology has shown great potential and value in scientific research and industrial applications in recent years. This technology cleverly combines optical measurement principles with advanced image processing algorithms. By projecting a series of carefully designed light and dark stripe patterns onto the surface of the object being measured, it can achieve high-precision 3D reconstruction of the surface morphology of the object. These stripes will deform when interacting with the surface of the object. The specific form of the deformation, including bending, stretching or compression of the stripes, directly maps the 3D geometric features of the surface of the object. Subsequently, high-resolution image acquisition equipment is used to capture the images of these deformed stripes, and through complex image processing and analysis algorithms, the 3D morphology model of the object can be accurately analyzed and reconstructed.

[0003] The advantages of stripe structured light technology are significant, mainly reflected in the following aspects: first, its measurement accuracy is extremely high, which can meet the needs of precise measurement of tiny deformations or complex surface structures; second, as a non-contact measurement technology, it avoids the physical damage that may be caused by traditional contact measurement, and also broadens the measurement range, suitable for objects of various shapes and materials; third, this technology can realize full-field measurement, that is, one measurement can obtain three-dimensional data of the entire area to be measured, greatly improving the measurement efficiency.

[0004] In view of the above advantages, stripe structured light technology has been widely used in many fields. In the field of industrial manufacturing, it has become an indispensable tool for quality control and precision manufacturing, used to accurately detect the size, shape accuracy and surface defects of parts; in the field of biomedicine, this technology provides strong support for human tissue morphology research, medical diagnosis and the formulation of personalized treatment plans, such as skin lesion analysis, tooth arrangement assessment and bone structure reconstruction; in addition, stripe structured light technology has also played a key role in the protection and digital recording of cultural heritage. By capturing and reconstructing the three-dimensional information of the surface of cultural relics with high precision, it has opened up new ways for the digital archiving, restoration and display of cultural heritage.

[0005] However, despite the many advantages of stripe structured light technology, the design and manufacture of its core component, the stripe projection device, still face many challenges. The mainstream stripe projection devices on the market are mainly based on DLP (digital light processing) projectors or MEMS (micro-electromechanical systems) galvanometer scanning technology. Although the DLP projector can provide high-quality image output, its system structure is relatively complex, the volume is large, and the energy consumption is high, which increases the cost and maintenance difficulty of the equipment. Although the projection device based on MEMS galvanometer scanning has achieved miniaturization and lightweight to a certain extent, it is limited by the scanning speed and accuracy of the galvanometer, and its projection efficiency and light energy utilization still need to be improved. These problems not only limit the further popularization and optimization of stripe structured light technology, but also hinder its application in more fields, especially in scenarios with strict requirements on equipment size and power consumption.

[0006] Therefore, developing a stripe projection device with simpler structure, smaller size, higher power, better energy efficiency and more reasonable cost has become the key to promoting the sustainable development of stripe structured light technology. Summary of the invention

[0007] The embodiments of the present application provide a fully solid-state fringe projection device and a 3D structured light measurement system, which can solve the problems of complex structure and large volume of fringe projection devices in the prior art. The technical solution is as follows: In a first aspect, the embodiments of the present application provide a light source and an optical projection system; the light source includes a VCSEL array, the VCSEL array includes a plurality of VCSEL line groups, each VCSEL line group includes at least one VCSEL light-emitting hole, and each VCSEL light-emitting hole is used to emit a laser signal; The light source is used to drive each VCSEL line group in the plurality of VCSEL arrays to turn on or off according to the pattern type, and to emit a laser signal based on all the turned-on VCSEL line groups; The optical projection system is used to collimate the laser signal from the light source, to modulate the light field of the laser signal laterally and longitudinally, and to project the processed laser signal onto the object to be measured to form a stripe pattern.

[0008] In a second aspect, an embodiment of the present application provides a 3D structured light measurement system, comprising: at least one camera and the all-solid-state fringe projection device.

[0009] The beneficial effects brought about by the technical solutions provided by some embodiments of the present application include at least: 1. High reliability: The all-solid-state fringe projection device does not contain any moving parts and relies entirely on solid-state electronic components and optical components to achieve its functions. This design greatly reduces the risk of failure due to mechanical movement and improves the reliability and stability of the device. Therefore, the device can maintain good performance in long-term operation and complex environments.

[0010] 2. Lightweight and miniaturization: The structural design of the stripe projection device is simple and clear, and only includes two parts: the light source (VCSEL array) and the optical projection system. This simple structure enables the device to greatly reduce weight and size while achieving its functions. This is a great advantage for application scenarios that require portability or are space-constrained.

[0011] 3. High signal-to-noise ratio and measurement accuracy: By utilizing the high brightness characteristics of VCSEL, the device can emit high-intensity laser signals. This not only improves the contrast of the fringe pattern, but also significantly increases the signal-to-noise ratio of the fringe projection. The fringe pattern with a high signal-to-noise ratio can more accurately reflect the surface morphology of the object to be measured, thereby improving the measurement accuracy of the system.

[0012] 4. Strong resistance to ambient light interference: By selecting VCSEL in the infrared band and combining it with the use of filters, the device can significantly reduce the interference of ambient light on the stripe pattern. This design enables the device to maintain good measurement results outdoors or in environments with complex light, broadening the application scenarios.

[0013] 5. High energy utilization efficiency: The laser energy emitted by VCSEL is fully utilized for the projection of stripe patterns, without any energy loss or waste. This highly efficient energy utilization method not only improves the energy efficiency of the device, but also reduces operating costs.

[0014] 6. High frame rate: VCSEL has an extremely high response speed and can be turned on or off quickly to form a stripe pattern. This feature enables the device to achieve high frame rate stripe projection, thus meeting the needs of fast or dynamic measurement.

[0015] 7. Low cost: The fringe projection device only uses VCSEL and basic optical components, without introducing complex or expensive mechanical structures. This simple design effectively controls the cost of the device and has the advantage of low cost. At the same time, due to the mass production capacity of VCSEL and optical components, the cost of the device is expected to be further reduced in the future. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 is a schematic structural diagram of a fully solid-state fringe projection device provided in an embodiment of the present application; Figure 2 is a schematic diagram of the structure of a VCSEL array provided in an embodiment of the present application; Figure 3 It is a schematic diagram of the arrangement of VCSEL light-emitting holes in a VCSEL line group provided in an embodiment of the present application; Figure 4 is a schematic diagram of the structure of the optical projection system provided by the present application; Figure 5 This is a schematic diagram of the VCSEL array configuration and projection process for realizing eight-stripes four-step phase-shifted stripe pattern projection provided by the present application; Figure 6 It is a schematic diagram of complementary Gray code projection provided by this application. DETAILED DESCRIPTION

[0018] In order to make the objectives, technical solutions and advantages of the present application more clear, the embodiments of the present application will be further described in detail below with reference to the accompanying drawings.

[0019] Figure 1 A structural schematic diagram of a fully solid-state stripe projection device that can be applied to the present application is shown, including: a light source and an optical projection system, the light source includes a VCSEL array, and the VCSEL array is a VCSEL light-emitting hole array composed of a single or multiple VCSEL chips.

[0020] See also Figure 2 The structural schematic diagram of the VCSEL array shown in the figure, the VCSEL array includes multiple VCSEL line groups, each VCSEL line group includes at least one VCSEL light-emitting hole, and each VCSEL light-emitting hole is used to emit a laser signal. The light-emitting light source is used to drive each VCSEL line group in the multiple VCSEL arrays to turn on or off according to the pattern type, and to emit a laser signal based on all the turned-on VCSEL line groups.

[0021] The core of the light source is the VCSEL (Vertical Cavity Surface Emitting Laser) array, which is composed of multiple VCSEL line groups, each of which contains at least one VCSEL light-emitting hole.

[0022] Each VCSEL light-emitting hole can independently emit laser signals, which will be modulated and projected onto the object to be measured in the subsequent process. According to the specific pattern type (such as phase-shifted stripes, binary coding, Gray code, etc.), the control system will accurately drive each VCSEL line group in the VCSEL array to turn on or off. The encoding method not only determines the style of the stripe pattern, but also directly affects the accuracy and efficiency of subsequent 3D reconstruction. Under the control of the pattern type, all turned-on VCSEL line groups will emit laser signals at the same time, and the laser signals will then be received and processed by the optical projection system.

[0023] The optical projection system is used to collimate the laser signal from the light source, to modulate the light field of the laser signal laterally and longitudinally, and to project the processed laser signal onto the object to be measured to form a stripe pattern.

[0024] The optical projection system first collimates the laser signal from the light source. The purpose of this step is to ensure that the laser signal has a consistent propagation direction and divergence angle, thereby improving the clarity of the fringe pattern projected onto the object to be measured.

[0025] Transverse modulation refers to the modulation of the transverse energy distribution of the light field to change the intensity distribution of the laser signal on the cross section. In this technical solution, the purpose of transverse modulation is to make the transverse distribution of the light field close to the cosine function, forming a stripe pattern of alternating light and dark. Transverse modulation is usually achieved through optical elements (such as cylindrical mirrors, wave mirrors, linear homogenizers, etc.). These elements can modulate the wavefront of the laser signal to introduce a specific intensity distribution on the cross section. By precisely designing and manufacturing optical elements, it can be ensured that the light field distribution after transverse modulation conforms to the expected cosine function shape. This helps to improve the contrast and clarity of the stripe pattern, thereby improving the accuracy of 3D reconstruction.

[0026] Longitudinal modulation refers to the modulation of the longitudinal energy distribution of the light field to change the energy distribution of the laser signal in the propagation direction. In this technical solution, the purpose of longitudinal modulation is to expand the laser energy emitted by each VCSEL light-emitting hole in the VCSEL line group into a line of light in the longitudinal direction, and increase the light energy after superposition. Longitudinal modulation can achieve longitudinal energy expansion and superposition through devices such as cylindrical mirrors, wave mirrors, and line homogenizers. After longitudinal modulation, the laser energy emitted by each VCSEL light-emitting hole will be expanded and superimposed in the longitudinal direction to form a light with higher energy. This helps to improve the brightness and contrast of the stripe pattern projected onto the object to be measured, thereby enhancing the reliability and accuracy of three-dimensional reconstruction.

[0027] In some embodiments of the present application, see Figure 3The schematic diagram of the arrangement of VCSEL light-emitting holes in the VCSEL line group shown is a schematic diagram of the arrangement of VCSEL light-emitting holes in the VCSEL line group. When the VCSEL line group includes multiple VCSEL light-emitting holes, the arrangement of the multiple VCSEL light-emitting holes includes but is not limited to: single-row arrangement, staggered arrangement, inclined arrangement or multi-row arrangement.

[0028] Among them, single-row arrangement means that all VCSEL light-emitting holes are arranged along a straight line. Single-row arrangement is simple and clear, but there is only one row, and the upper limit of light energy that can be achieved is low. At the same time, there is no lateral distribution of light-emitting holes, and the lateral energy distribution of the light field can only be controlled by adjusting the design of the lateral modulation unit, which brings challenges to optical design.

[0029] Staggered arrangement means that the VCSEL light-emitting holes are arranged alternately in the horizontal direction, forming a layout similar to a chessboard. Staggered arrangement can increase the density of the light-emitting holes in the column direction. By designing the lateral misalignment of the staggered light-emitting holes, the lateral width of the projected stripes can be affected. Combined with the lateral modulation unit, more flexible regulation of the lateral energy distribution of the stripes can be achieved.

[0030] The tilted arrangement means that the VCSEL light-emitting holes are arranged along an oblique line or curve. The tilted arrangement can increase the density of the light-emitting holes in the column direction. Compared with the staggered arrangement, wider stripe projection can be achieved.

[0031] Multi-column arrangement refers to arranging multiple VCSEL light-emitting holes into multiple columns. Multi-column arrangement is used to increase the energy of the line group and significantly improve the measurement accuracy. It can be combined with staggered arrangement and tilted arrangement to increase the column-wise arrangement density of the light-emitting holes, and combined with the lateral modulation unit to achieve more flexible stripe lateral energy distribution control.

[0032] In some embodiments of the present application, see Figure 4 The structural schematic diagram of the optical projection system shown in the figure, the optical projection system includes: a collimation unit, a transverse modulation unit and a longitudinal modulation unit.

[0033] The collimator includes a collimator composed of at least one lens, the transverse modulation unit includes: a cylindrical mirror, a wavy mirror or a light homogenizer, and the longitudinal modulation unit includes: a cylindrical mirror, a wavy mirror or a light homogenizer.

[0034] The collimator collimates the light field emitted by the VCSEL array to ensure that the light is projected to the target area in a parallel or nearly parallel state. This can be achieved by a collimator consisting of a single or multiple lenses. The selection and design of the lens should be determined according to the light-emitting characteristics of the VCSEL array, the projection distance, and the size of the target area.

[0035] The transverse modulation unit modulates the transverse energy of the light field so that the transverse distribution of the light field is close to the cosine function. This can be achieved by a cylindrical mirror, a wave mirror or a homogenizer. The cylindrical mirror focuses or diverges the light through its curved surface design, thereby forming a specific intensity distribution in the transverse direction. The wave mirror introduces phase changes through its wavy surface to achieve transverse modulation of the light field. The homogenizer scatters and redistributes the light through its internal microstructure to achieve the purpose of transverse modulation.

[0036] Longitudinal modulation unit: modulates the longitudinal energy of the light field, so that the energy of the light-emitting holes in the VCSEL line group is expanded into a stripe along the longitudinal direction, and the stripe energy is increased after superposition. It can also be achieved by cylindrical mirrors, wave mirrors or light homogenizers, but the modulation direction is different from that of the transverse modulation unit. By adjusting the position, angle, focal length and other parameters of the optical element, the longitudinal energy of the light field can be precisely controlled.

[0037] It should be noted that the order of the collimation unit, the transverse modulation unit, and the longitudinal modulation unit in the optical system of the present application can be flexibly adjusted.

[0038] In addition to the above designs, there are a variety of optical design solutions to achieve the same purpose: 1. Combined transverse and longitudinal modulation units: Use a single cylindrical mirror, wave mirror or light homogenizer to achieve both transverse and longitudinal modulation. Optical components need to be precisely designed and manufactured to ensure that they can meet the requirements of both transverse and longitudinal modulation.

[0039] 2. Single element achieves multi-functions: Use a single light homogenizer or metasurface element to achieve the purpose of collimation, lateral modulation and longitudinal modulation at the same time. Metasurface element is a new type of optical element that can achieve precise control of the light field through the micro-nano structure on its surface. This design can greatly simplify the structure of the optical system and reduce cost and complexity.

[0040] 3. Eliminate the transverse modulation unit: Use the rotation angle between the longitudinal arrangement of the VCSEL line group and the longitudinal modulation unit for transverse modulation. By adjusting the arrangement of the VCSEL line group and the angle of the longitudinal modulation unit, the transverse modulation effect can be achieved without adding additional optical elements. However, this design requires precise calculation and optimization of the overall layout of the VCSEL array and the optical system.

[0041] In summary, there are many possibilities for the design and implementation of optical projection systems, and the most suitable solution can be selected based on specific application requirements and cost considerations. In practical applications, the performance of the optical system needs to be tested and evaluated in detail to ensure that it can meet the expected measurement and reconstruction accuracy requirements.

[0042] See also Figure 5 As shown, Figure 5The VCSEL array configuration and projection process for realizing eight-strip four-step phase-shifted fringe pattern projection are shown. This diagram is intended to intuitively show how to achieve the desired phase fringe pattern projection by precisely controlling different line groups in the VCSEL array.

[0043] Figure 5 In the VCSEL array, the VCSEL array is divided into 32 VCSEL line groups, which are arranged in the horizontal direction. Each line group contains at least one VCSEL light-emitting hole for emitting laser signals. For the convenience of explanation, Figure 5 The wire groups in the FPGA are numbered sequentially from 1 to 32. These numbers help to accurately specify which wire groups are turned on in a specific phase in the subsequent description.

[0044] When projecting 0° phase fringes, Figure 5 It shows that the 1st, 5th, 9th, ..., 29th line groups (actually an arithmetic progression) are turned on. After being processed by the optical projection system, these turned on line groups form column fringes with a transverse energy distribution close to cosine and a phase of 0°.

[0045] When projecting 90° phase fringes, the 2nd, 6th, 10th, ..., 30th line groups are turned on. Similar to the 0° phase projection, the fringe patterns formed by these line groups appear as cosine-shaped column fringes with a phase difference of 90° under the processing of the optical projection system.

[0046] When projecting 180° phase stripes, the 3rd, 7th, 11th, ..., 31st column line groups are activated. The stripe patterns generated by these line groups are the same as the 0° phase stripe pattern, but the phase difference is 180°, that is, the light and dark distribution of the stripes is opposite.

[0047] Finally, when projecting 270° phase stripes, the 4th, 8th, 12th, ..., 32nd line groups are turned on. Similar to the 90° phase projection, the stripe patterns formed by these line groups have a phase difference of 270°, that is, relative to the 90° phase stripes, the light and dark distribution is opposite again.

[0048] Figure 5 Through concise schematic diagrams and clear instructions, it is demonstrated how to achieve the projection of eight-strip four-step phase-shifted fringe patterns by precisely controlling the line groups in the VCSEL array. This projection method not only improves the accuracy and efficiency of three-dimensional reconstruction, but also provides strong support for the precise measurement of complex object surfaces.

[0049] Figure 6 A schematic diagram showing complementary Gray code projection by recombining the on and off states of groups of VCSEL lines. This illustration is intended to illustrate how to precisely control the groups of lines in a VCSEL array to produce complementary Gray code fringe patterns with uniform energy distribution.

[0050] Figure 6 The VCSEL array in the system is divided into multiple VCSEL line groups, which are arranged in the horizontal direction and numbered for easy control. Each line group contains at least one VCSEL light-emitting hole, which is used to emit laser signals under specific conditions. Gray code is a binary coding system in which only one binary bit differs between two adjacent values. This property enables Gray code to reduce errors when converting digital systems. In this scheme, by precisely controlling the opening and closing of the line groups in the VCSEL array, a stripe pattern with Gray code characteristics can be projected.

[0051] Specific projection process: Primary Gray code: Turn on the 18th, 20th, ..., 32nd column line groups to form a primary Gray code stripe pattern.

[0052] Secondary Gray code: Turn on the 10th, 12th, ..., 24th column line groups to form a secondary Gray code stripe pattern.

[0053] Three-level Gray code: Open the 6th, 8th, 10th, 12th, 22nd, 24th, 26th, and 28th column lines to form a three-level Gray code stripe pattern. Note that there is a combination of interval opening and continuous opening, which reflects the flexibility of Gray code encoding.

[0054] Four-level Gray code: Turn on the 4th, 6th, 12th, 14th, 20th, 22nd, 28th, and 30th column line groups to form a four-level Gray code stripe pattern.

[0055] Since the energy of cosine fringes with a phase difference of 180° is complementary, a relatively uniform complementary Gray code energy distribution can be obtained by precisely controlling the opening and closing of the line group. This uniformity of energy distribution helps to improve the robustness of the aforementioned four-step phase shift fringe phase unwrapping, as well as the accuracy and stability of 3D reconstruction or object surface measurement.

[0056] Figure 6 Although only four examples of Gray code projection are shown, this solution is not limited to these specific stripe projections. By adjusting the configuration of the VCSEL array and the design of the optical projection system, projection of stripe patterns with different numbers of stripes, phase shifts, and other types of Gray codes or binary codes can be achieved. This scalability and flexibility enables this solution to adapt to a variety of application scenarios and needs, providing strong support for fields such as 3D reconstruction and object surface measurement.

[0057] The all-solid-state fringe projection device of the present application has the following technical effects: The all-solid-state fringe projection device does not contain any moving parts and relies entirely on solid-state electronic components and optical components to achieve its functions. This design greatly reduces the risk of failure caused by mechanical movement and improves the reliability and stability of the device. Therefore, the device can maintain good performance in long-term operation and complex environments.

[0058] The structural design of the stripe projection device is concise and clear, consisting of only two parts: the light source (VCSEL array) and the optical projection system. This simple structure enables the device to achieve its functions while greatly reducing weight and size. This is a great advantage for application scenarios that require portability or are space-constrained.

[0059] By utilizing the high brightness characteristics of VCSEL, the device can emit high-intensity laser signals. This not only improves the contrast of the fringe pattern, but also significantly increases the signal-to-noise ratio of the fringe projection. The fringe pattern with a high signal-to-noise ratio can more accurately reflect the surface morphology of the object to be measured, thereby improving the measurement accuracy of the system.

[0060] By selecting VCSEL in the infrared band and combining it with filters, the device can significantly reduce the interference of ambient light on the stripe pattern. This design enables the device to maintain good measurement results outdoors or in environments with complex lighting, broadening its application scenarios.

[0061] The laser energy emitted by the VCSEL is fully utilized for the projection of the stripe pattern, with no energy loss or waste. This highly efficient energy utilization method not only improves the energy efficiency of the device, but also reduces operating costs. The VCSEL has an extremely high response speed and can be turned on or off quickly to form a stripe pattern. This feature enables the device to achieve high frame rate stripe projection, thus meeting the needs of fast or dynamic measurement.

[0062] The fringe projection device only uses VCSEL and basic optical components, without introducing complex or expensive mechanical structures. This simple design effectively controls the cost of the device and has the advantage of low cost. At the same time, due to the mass production capacity of VCSEL and optical components, the cost of the device is expected to be further reduced in the future.

[0063] In summary, the all-solid-state fringe projection device proposed in this technical solution has significant advantages in reliability, light weight and miniaturization, signal-to-noise ratio and measurement accuracy, ability to resist ambient light interference, energy efficiency, frame rate and cost, etc. These advantages make the device have broad application prospects in the fields of three-dimensional measurement, object recognition, intelligent manufacturing, etc.

[0064] Furthermore, the all-solid-state fringe projection device proposed in this scheme integrates an advanced VCSEL (vertical cavity surface emitting laser) array and a precise optical projection system, which can efficiently and stably project fringe patterns with specific coding characteristics. The device not only has the characteristics of high brightness and high energy efficiency, but also has a small size and light weight, making it easy to integrate into various 3D measurement systems.

[0065] The monocular 3D measurement system consists of a camera and a fully solid-state fringe projection device. The camera and the fringe projection device are separated by a certain distance to form the baseline of triangulation, which is the key to achieve depth measurement. The fringe projection device projects multiple fringe patterns with unique spatial codes onto the surface of the object being measured. The camera captures fringe images on the surface of the object being measured, which contain the spatial coding position differences caused by the object's morphology. The depth information of the object can be calculated by matching and comparing the pre-recorded planar spatial coding distribution with the spatial coding of the object being measured. The calibration relationship between the camera, fringe projection device and reference plane is combined to further improve the measurement accuracy.

[0066] The binocular 3D measurement system consists of two cameras and a fully solid-state fringe projection device. The two cameras are spaced a certain distance apart and also form a baseline for triangulation. The fringe projection device projects a spatially encoded fringe pattern onto the surface of the object being measured. The two cameras capture fringe images of the surface of the object being measured, respectively, and these images contain position differences that are uniquely encoded in space. The depth information of the object can be calculated based on the spatial position relationship of the two cameras obtained by calibration and the spatial encoding difference obtained by decoding the projected fringe pattern. Based on the monocular system, the binocular system further improves the reliability and accuracy of the measurement by adding a camera. The binocular system can handle objects with complex morphology more accurately and reduce measurement errors.

[0067] The monocular and binocular fringe 3D structured light measurement systems based on the all-solid-state fringe projection device proposed in this scheme have multiple advantages such as high frame rate, high energy efficiency, small size, light weight, high precision and long measurement distance. These systems are not only suitable for industrial inspection, intelligent manufacturing, cultural relics protection and other fields, but can also be widely used in medical, entertainment, virtual reality and other industries, providing strong technical support for three-dimensional measurement and reconstruction. Through continuous optimization and improvement, this scheme is expected to play an important role in a wider range of fields.

[0068] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiments can be implemented by instructing related hardware through a computer program, and the program can be stored in a computer-readable storage medium, and when the program is executed, it can include the processes of the embodiments of the above-mentioned methods. The storage medium can be a disk, an optical disk, a read-only storage memory, or a random access memory, etc.

[0069] The above disclosure is only the preferred embodiment of the present application, which certainly cannot be used to limit the scope of rights of the present application. Therefore, equivalent changes made according to the claims of the present application are still within the scope covered by the present application.

Claims

1. A fully solid-state fringe projection device, characterized in that: include: A light source and an optical projection system; the light source comprises a VCSEL array, the VCSEL array comprises a plurality of VCSEL line groups, each VCSEL line group comprises at least one VCSEL light-emitting hole, and each VCSEL light-emitting hole is used to emit a laser signal; The light source is used to drive each VCSEL line group in the plurality of VCSEL arrays to turn on or off according to the pattern type, and to emit a laser signal based on all the turned-on VCSEL line groups; The optical projection system is used to collimate the laser signal from the light source, to modulate the light field of the laser signal laterally and longitudinally, and to project the processed laser signal onto the object to be measured to form a stripe pattern.

2. The device according to claim 1, characterized in that When the VCSEL line group includes a plurality of VCSEL light emitting control holes, the arrangement of the plurality of VCSEL light emitting holes includes but is not limited to: single-row arrangement, staggered arrangement, inclined arrangement or multi-row arrangement.

3. The device according to claim 1, characterized in that The optical projection system comprises: a collimation unit, a transverse modulation unit and a longitudinal modulation unit; The collimation unit is used to collimate the light field emitted by the VCSEL array to ensure that the light is projected to the target area in a parallel or approximately parallel state; A lateral modulation unit is used to modulate the lateral energy of the light field emitted by the VCSEL line group so that the lateral distribution of the light field is close to a cosine function; The longitudinal modulation unit is used to modulate the longitudinal energy of the light field emitted by the VCSEL line group, so that the energy of the light-emitting holes in the VCSEL line group is expanded into stripes along the longitudinal direction.

4. The device according to claim 3, characterized in that The collimator includes a collimator composed of at least one lens, the lateral modulation unit includes: one or more of a cylindrical mirror, a wavy mirror and a light homogenizer, and the longitudinal modulation unit includes: one or more of a cylindrical mirror, a wavy mirror and a light homogenizer.

5. The device according to claim 1, characterized in that Pattern types include but are not limited to: four-step phase-shift stripes, Gray code stripes, and binary code stripes.

6. The device according to claim 5, characterized in that The pattern type is four-step phase-shift stripes, and the VCSEL line group includes 32 VCSEL line groups; when projecting 0° phase stripes, the VCSEL line groups in the 1st, 5th, ..., 29th columns are turned on; when projecting 90° phase stripes, the VCSEL line groups in the 2nd, 6th, ..., 30th columns are turned on; when projecting 180° phase stripes, the VCSEL line groups in the 3rd, 7th, ..., 31st columns are turned on; when projecting 270° phase stripes, the VCSEL line groups in the 4th, 8th, ..., 32nd columns are turned on.

7. The device according to claim 5, characterized in that The pattern type is Gray code stripes, and the number of VCSEL line groups included in the VCSEL line group is 32; when the first-level Gray code is projected, the VCSEL line groups in the 18th, 20th, ..., 32nd columns are turned on; when the second-level Gray code is projected, the VCSEL line groups in the 10th, 12th, ..., 24th columns are turned on; when the third-level Gray code is projected, the VCSEL line groups in the 6th, 8th, 10th, 12th, 22nd, 24th, 26th, and 28th columns are turned on; when the fourth-level Gray code is projected, the VCSEL line groups in the 4th, 6th, 12th, 14th, 20th, 22nd, 28th, and 30th columns are turned on.

8. A 3D structured light measurement system, characterized in that: include: At least one camera and a fully solid-state fringe projection device as claimed in any one of claims 1-7.

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