Structured light three-dimensional detection system, method and device based on optical phased array coding

Abstract

The invention relates to the technical field of three-dimensional measurement, and discloses a structured light three-dimensional detection system, method and device based on optical phased array coding, the structured light three-dimensional detection system comprises an optical phased array module, an acquisition module and a control module, the control module is connected with the optical phased array module and the acquisition module, and the optical phased array module is connected with the acquisition module and the control module. The optical coding module is used for performing phase regulation and amplitude regulation on the optical signal based on a preset regulation instruction to generate an optical coding pattern, and projecting the optical coding pattern to the surface of the to-be-measured object, so that the to-be-measured object reflects the optical coding pattern to generate reflection coding light; the acquisition module is used for acquiring the reflection coding light to obtain a reflection coding pattern; and the control module is used for generating a preset regulation and control instruction, decoding the reflection coding pattern, extracting a coding value and calculating feature information of the to-be-measured object based on the coding value. The problem that the structure light source cannot be adjusted can be solved, and the flexibility and controllability of three-dimensional detection are improved.

Description

Technical Field

[0001] The present invention relates to the field of three-dimensional measurement technology, and in particular to a structured light three-dimensional detection system, method and device based on optical phased array coding. Background Art

[0002] Three-dimensional measurement technology can be divided into two categories: contact and non-contact. The contact measurement method relies on the probe to directly contact the surface of the object to be measured to obtain three-dimensional information. The non-contact measurement method uses light, sound, magnetism and other means to achieve long-distance measurement. Among them, structured light three-dimensional measurement technology is an important method in non-contact measurement. It can avoid physical damage to the object to be measured and can be used in scenes where contact is not allowed.

[0003] In structured light 3D measurement technology, the projected patterns can generally be divided into the following three categories according to the different light sources: point structured light, line structured light, and surface structured light. Point light sources are suitable for projecting small spots or stripes, line light sources are used to project continuous light stripes, and surface light sources can project complex patterns and grids. The role of the light source is not only to provide the necessary illumination, but also to achieve the time and space encoding of structured light.

[0004] Traditional structured light sources provide a single light intensity and color adjustment, and cannot achieve rapid switching of multiple light modes. When measuring irregularly shaped or fast-moving objects, it is difficult to quickly adjust the shape and size of the light spot, and it is impossible to achieve real-time projection of complex dynamic light patterns, making the existing structured light three-dimensional measurement less flexible and controllable. Summary of the invention

[0005] In view of this, the present invention provides a structured light three-dimensional detection system, method and device based on optical phased array coding to solve the problem that the structured light source cannot be adjusted and improve the flexibility and controllability of three-dimensional detection.

[0006] In a first aspect, the present invention provides a structured light three-dimensional detection system based on optical phased array coding, wherein the structured light three-dimensional detection system based on optical phased array coding includes an optical phased array module, an acquisition module and a control module, wherein the control module is connected to the optical phased array module and the acquisition module, wherein the optical phased array module is used to perform phase control and amplitude control on an optical signal based on a preset control instruction, generate an optical coding pattern, and project the optical coding pattern onto the surface of an object to be measured so that the object to be measured reflects the optical coding pattern to generate reflected coded light; the acquisition module is used to collect reflected coded light, obtain a reflected coded pattern, and send the reflected coded pattern to the control module; the control module is used to generate a preset control instruction, decode the reflected coded pattern, extract the coding value, and calculate the characteristic information of the object to be measured based on the coding value.

[0007] In this implementation, the present application replaces the traditional line light source with an optical phased array, and uses the optical phased array module to perform dual modulation of the phase and amplitude of the light signal according to the preset control instructions to generate an optical coding pattern of the preset target, thereby solving the problem of being unable to adjust the structured light source. The present application can achieve dynamic adjustment of the light intensity distribution and phase distribution of the light beam by adjusting the preset control instructions, which can solve the problem that the traditional line light source cannot achieve rapid switching of multiple light modes. The control module is used to decode and calculate the characteristic information of the object to be measured based on the generated coded image, which can improve the flexibility and controllability of three-dimensional detection. At the same time, by modulating the phase and amplitude separately, more three-dimensional information of the object to be measured can be encoded, improving measurement accuracy and efficiency.

[0008] In an optional embodiment, the optical phased array module includes a light source, a first beam splitter, a second beam splitter, a plurality of control units, a grating coupler and a projector, wherein the light source is used to output a light signal; the first beam splitter is used to perform beam splitting processing on the light signal to generate a plurality of sub-light signals; the control unit is used to perform phase control and amplitude control on the sub-light signals respectively based on preset control instructions to generate corresponding control signals; the second beam splitter is used to perform beam splitting processing on the control signal to generate a plurality of sub-control signals; the grating coupler is used to couple the plurality of sub-control signals to generate an optical coding pattern; and the projector is used to project the optical coding pattern onto the surface of the object to be measured.

[0009] In an optional embodiment, the control unit includes a phase shifter and an optical amplifier, and the preset control instruction includes a preset phase control voltage and a preset amplitude control voltage, wherein the phase shifter is used to perform phase control on the sub-optical signal based on the preset phase control voltage to generate a first control signal; and the optical amplifier is used to perform amplitude control on the first control signal based on the preset amplitude control voltage to generate a control signal.

[0010] In an optional embodiment, a phase shifter is used to adjust the refractive index of the sub-light signal under the action of a preset phase control voltage, form a phase difference between adjacent sub-light signals, and generate a first control signal; an optical amplifier is used to determine the amplification gain ratio of the first control signal under the action of a preset amplitude control voltage, and adjust the amplitude of the first control signal based on the amplification gain ratio to generate a control signal, wherein I2=G·I1; I2 is the amplitude of the control signal, G is the amplification gain ratio, and I1 is the amplitude of the first control signal.

[0011] In this implementation, the light source in the optical phased array module is used to provide the optical signal. The light source has the characteristics of stability and consistency, which improves the reliability of the final measurement results. The control unit is used to accurately control the phase and amplitude of each pixel point, and the dynamic adjustment of the light beam can be achieved through current control within nanoseconds. No mechanical moving parts are required. By changing the phase and intensity of each phased array unit, the shape and direction of the light beam can be quickly adjusted to meet the measurement requirements of different objects to be measured. Among them, the gain adjustment of the optical amplifier can ensure that the light intensity remains appropriate under complex surface conditions to improve the contrast of the reflected signal. Amplitude modulation can optimize the subsequent reflected light, so that the clarity of the reflected light is still guaranteed when the reflectivity of the surface of the object to be measured is uneven.

[0012] In an optional embodiment, the control module is also used to decode the reflection coding pattern using a trained neural network algorithm to extract the coding value; obtain the position relationship information between the optical phased array module, the acquisition module and the object to be measured; and calculate the characteristic information of the object to be measured based on the coding value and the position relationship information.

[0013] In an optional embodiment, the optical phased array module is further used to control the optical signal based on the training control instructions to generate a training coding pattern, and project the training coding pattern onto the surface of the standard object so that the standard object reflects the training coding pattern to generate training reflection coding light, and the training control instructions include random phase control instructions and random amplitude control instructions; the acquisition module is further used to acquire the training reflection coding light to obtain the training reflection coding pattern, and send the training reflection coding pattern to the control module; the control module is further used to generate training control instructions; it is also used to decode the training reflection coding pattern using a neural network algorithm, extract the training coding value, and calculate the training feature information of the standard object based on the training coding value; and train the neural network algorithm based on the standard feature information and training feature information of the standard object.

[0014] In this implementation, the coding pattern is decoded based on a machine learning algorithm to improve decoding accuracy and further improve the accuracy of object detection. When detecting objects with complex surfaces or large reflectivity changes, more accurate, efficient and robust decoding can be achieved.

[0015] In the second aspect, the present invention provides a structured light three-dimensional detection method based on optical phased array coding, which is applied to the above-mentioned structured light three-dimensional detection system based on optical phased array coding. The structured light three-dimensional detection system method based on optical phased array coding includes: generating preset control instructions; performing phase control and amplitude control on the optical signal based on the preset control instructions to generate an optical coding pattern, and projecting the optical coding pattern onto the surface of the object to be measured so that the object to be measured reflects the optical coding pattern to generate reflected coded light; collecting the reflected coded light to obtain the reflected coded pattern, and sending the reflected coded pattern to the control module; decoding the reflected coded pattern, extracting the coding value, and calculating the characteristic information of the object to be measured based on the coding value.

[0016] In this implementation, the present application uses an optical phased array module to perform dual modulation of the phase and amplitude of the optical signal according to preset control instructions, generates an optical coding pattern of a preset target, and solves the problem of being unable to adjust the structured light source. The present application can achieve dynamic adjustment of the light intensity distribution and phase distribution of the light beam by adjusting the preset control instructions, which can solve the problem that traditional line light sources cannot achieve rapid switching of multiple light modes. The characteristic information of the object to be measured is decoded and calculated based on the generated coded image, which can improve the flexibility and controllability of three-dimensional detection. At the same time, modulating the phase and amplitude separately can encode more three-dimensional information of the object to be measured, improving measurement accuracy and efficiency.

[0017] In a third aspect, the present invention provides a computer device, comprising: a memory and a processor, the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the structured light three-dimensional detection method based on optical phased array coding of the above-mentioned first aspect or any corresponding embodiment thereof by executing the computer instructions.

[0018] In a fourth aspect, the present invention provides a computer-readable storage medium having computer instructions stored thereon, the computer instructions being used to enable a computer to execute the structured light three-dimensional detection method based on optical phased array coding according to the first aspect or any corresponding embodiment thereof.

[0019] In a fifth aspect, the present invention provides a computer program product, comprising computer instructions, wherein the computer instructions are used to enable a computer to execute the structured light three-dimensional detection method based on optical phased array coding according to the first aspect or any corresponding embodiment thereof. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 is a schematic structural diagram of a structured light three-dimensional detection system according to an embodiment of the present invention;

[0022] Figure 2 is a schematic diagram of the operation of generating an optical coding pattern by an optical phased array according to an embodiment of the present invention;

[0023] Figure 3 is a flow chart of a structured light three-dimensional detection method based on optical phased array coding according to an embodiment of the present invention;

[0024] Figure 4 It is a schematic diagram of the hardware structure of a computer device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0026] The principle of structured light 3D detection is to project a specific structured light pattern (such as stripes or grids) onto the surface of the object to be measured through a light source. After the light pattern is modulated by the surface morphology of the object to be measured, the light pattern changes. Specifically, the light stripes are offset or intermittent, and the degree of offset is related to the morphology of the object to be measured. The camera is used to capture the changed light pattern. By calculating and analyzing the changed light pattern, the 3D shape and surface features of the object to be measured are reconstructed.

[0027] First, structured light 3D measurement technology can avoid physical damage to the object being measured, and is applicable not only to scenarios where contact is allowed, but also to scenarios where contact is not allowed. Second, structured light 3D measurement technology can achieve high-precision and high-resolution measurements, and can be applied to the detection of objects with complex shapes and subtle features. In addition, structured light 3D measurement is fast and can obtain a large amount of 3D data in a short time. It can be applied to applications that require fast measurement and real-time analysis. The diverse light mode design also makes it adaptable to different environmental conditions.

[0028] When measuring irregular shapes or fast-moving objects, the current traditional line light source cannot respond to the required changes in speed, resulting in a decrease in measurement accuracy. At the same time, traditional line light sources can usually only provide a single light intensity and color adjustment, and cannot achieve rapid switching of multiple light modes, which limits its application in diverse measurement environments. In addition, line light sources are large in size and are not suitable for applications in miniaturized and portable devices. Large light sources require more space for installation and operation, which is not conducive to flexible measurement in small spaces or on-site environments. At the same time, in order to achieve high-precision measurement, line light sources usually also require complex optical and mechanical systems to support, which further increases the size and weight of the equipment and affects the portability and ease of use of the system. In addition, the quality and uniformity of the light spot of the line light source cannot usually be guaranteed, especially in scenarios with high resolution requirements. The monitoring of tiny light spots is poor, which introduces measurement errors and affects the accuracy of the measurement results.

[0029] Although point light sources and surface light sources can provide more flexible spot control in some applications, they also have problems such as uneven light intensity distribution and speckle noise, which reduce measurement accuracy. At the same time, light sources have problems such as heat generation, high power consumption and short life.

[0030] On this basis, the present application proposes a structured light three-dimensional detection system based on optical phased array coding, which replaces the traditional line light source with an optical phased array, and uses the optical phased array module to dual-modulate the phase and amplitude of the light signal according to the preset control instructions to generate an optical coding pattern of the preset target, thereby solving the problem of being unable to adjust the structured light source. The present application can dynamically adjust the light intensity distribution and phase distribution of the light beam by adjusting the preset control instructions, which can solve the problem that the traditional line light source cannot achieve rapid switching of multiple light modes. The control module is used to decode and calculate the characteristic information of the object to be measured based on the generated coded image, which can improve the flexibility and controllability of three-dimensional detection. At the same time, by modulating the phase and amplitude separately, more three-dimensional information of the object to be measured can be encoded, thereby improving the measurement accuracy and efficiency.

[0031] According to an embodiment of the present invention, an embodiment of a structured light three-dimensional detection system based on optical phased array coding is provided. Figure 1 , Figure 1 4 is a schematic diagram of the structure of a structured light three-dimensional detection system according to an embodiment of the present invention.

[0032] like Figure 1 As shown, the structured light three-dimensional detection system based on optical phased array coding includes an optical phased array module 1, a collection module 2 and a control module 3, wherein the control module 3 is connected to the optical phased array module 1 and the collection module 2 respectively.

[0033] Among them, Optical Phase Array (OPA) is a technology that uses adjustable optical elements, such as optical phase shifters and adjustable gratings, to control and modulate light waves. Among them, the optical phase array can be integrated on the chip to achieve miniaturization and lightweight, and can adapt to portable devices and other space-constrained application scenarios.

[0034] The acquisition module 2 is a device that can acquire optical signals, such as a high-speed camera, a sensor, etc.

[0035] The control module 3 is a device with computing and control functions, such as a computer device.

[0036] In one implementation, the control module 3 generates a preset control instruction and sends the preset control instruction to the optical phased array module 1. The optical phased array module 1 receives the preset control instruction sent by the control module 3, and performs phase control and amplitude control on the optical signal based on the preset control instruction to generate an optical coding pattern.

[0037] Among them, the phase control of the optical signal can adjust the refractive index of each pixel point in the optical coding pattern to adjust the phase distribution information. The amplitude control of the optical signal can adjust the light intensity information of each pixel point in the optical coding pattern.

[0038] The optical coding pattern includes Gray code and phase coding pattern.

[0039] The optical phased array module 1 projects an optical coding pattern onto the surface of the object to be measured. The topography of the object to be measured modulates the optical coding pattern, so that the light mode of the optical coding pattern on the surface of the object to be measured changes. The optical coding pattern is reflected on the surface of the object to be measured to generate reflected coded light.

[0040] It can be understood that due to the different morphological structures of the objects to be measured, the same optical coding pattern is projected onto the surfaces of different objects to be measured, and the reflected coded light generated by reflection is different, and the reflected coded light is related to the morphological structure of the objects to be measured.

[0041] Specifically, see Figure 2 , Figure 2 FIG. 1 is a schematic diagram of the operation of an optical phased array generating an optical coding pattern according to an embodiment of the present invention. Figure 2 As shown, the optical phased array module 1 includes a light source 11, a first beam splitter 12, a plurality of control units 13, a second beam splitter 14, a grating coupler 15 and a projector (not shown in the figure).

[0042] Among them, the beam splitter includes a directional coupler, a Y-branch coupler, a multimode interference coupler, and the like.

[0043] The light source 11 is used to output an optical signal, and the optical signal passes through the first beam splitter 12, which splits the optical signal and distributes the optical signal to each pixel point, and is divided into multiple sub-optical signals. The light source 11 can be a light-emitting device such as a laser.

[0044] Specifically, the first beam splitter 12 first divides the optical signal into two optical signals of equal power. The two optical signals pass through a transverse modulation module and a longitudinal modulation module respectively. The transverse modulation module is used to modulate the transverse sub-optical signal, and the longitudinal modulation module is used to modulate the longitudinal sub-optical signal.

[0045] In this implementation, a light source in an optical phased array module is used to provide an optical signal. The light source has the characteristics of stability and consistency, thereby improving the reliability of the final measurement result.

[0046] The optical signal is modulated in the transverse modulation module and passes through n-level equal power beam splitters to generate 2 n The light signal is modulated in the longitudinal direction by m-level equal power beam splitters to generate 2 m The longitudinal sub-light signals are obtained by using equal-power light beams, where each light beam is used as a channel.

[0047] Furthermore, the multiple sub-optical signals pass through different control units 13 respectively, and the control unit 13 performs phase control and amplitude control on each sub-optical signal according to a preset control instruction to generate a control signal corresponding to each sub-optical signal.

[0048] It can be understood that the preset control instruction includes the control instruction of each sub-optical signal, and the control unit 13 can perform the same or different phase control and amplitude control on each sub-optical signal.

[0049] In one implementation, the control unit 13 includes a phase shifter 131 and an optical amplifier 132 , and the preset control instruction includes a preset phase control voltage and a preset amplitude control voltage.

[0050] The phase shifter 131 is used to perform phase control on the sub-optical signal based on a preset phase control voltage to generate a first control signal; the optical amplifier 132 is used to perform amplitude control on the first control signal based on a preset amplitude control voltage to generate a control signal.

[0051] Among them, the phase shifter 131 includes an optical element, a cross electrode and a reflector. The phase modulation of the phase shifter 131 is based on the electro-optical effect. Under the action of a preset phase control voltage, the optical properties of the optical element, such as the refractive index and the phase, are adjusted to form a phase difference between adjacent sub-light signals, thereby realizing light signal modulation and generating a first control signal.

[0052] Specifically, a preset phase control voltage is applied to the cross electrodes to generate an electric field. The electric field acts on the optical element to generate a photocurrent related to the frequency of the optical signal, which affects the optical properties of the optical element, causing the refractive index of the optical element to change periodically, thereby achieving high-speed modulation to produce a phase difference. When the phase difference between adjacent waveguides in each direction is constant, similar to multi-slit interference, each pixel is equivalent to an emitting light source 11, and the array light interferes when propagating in space, thereby achieving the deflection of the propagation angle of the light beam in each direction. Among them, the deflection angle θ of the light beam emitted by the pixel point is related to the phase difference of the adjacent waveguide. The relationship between the spacing d between adjacent waveguides is:

[0053] Specifically, a phase shifter 131 is set in each light beam channel, and a preset phase control voltage is applied to the phase shifter 131 to independently adjust the refractive index of each channel, that is, the phase of the optical element of each channel is quickly adjusted through the electro-optical effect so that adjacent waveguides form the same phase difference, and a first control signal is output.

[0054] Among them, the optical amplifier 132 can adjust the intensity distribution of the light beam, determine the amplification gain ratio of the first control signal under the action of the amplitude control voltage, and adjust the amplitude of the first control signal based on the amplification gain ratio to generate a control signal, wherein the amplitude I2 of the output control signal is: I2=G·I1; wherein G is the amplification gain ratio, and I1 is the amplitude of the first control signal.

[0055] Specifically, an optical amplifier 132 is provided in each light beam channel, and a preset amplitude control voltage is applied to the optical amplifier 132 to independently adjust the amplification gain ratio of each channel and output a control signal.

[0056] In this implementation, the gain adjustment of the optical amplifier can ensure that the light intensity remains appropriate under complex surface conditions to improve the contrast of the reflected signal. Amplitude modulation can optimize the subsequent reflected light so that the clarity of the reflected light is still guaranteed when the reflectivity of the surface of the object to be measured is uneven.

[0057] Furthermore, the control signal passes through the second beam splitter 14, and the second beam splitter 14 performs beam splitting processing on the control signal, dividing each control signal into multiple sub-control signals.

[0058] Specifically, 2 are set in each transverse beam channel. m A second beam splitter 14 generates 2 m equal power beams, and obtain 2 horizontal m+n Sub-control signals; set 2 in each longitudinal beam channel nA second beam splitter 14 generates 2 n equal power beams, and obtain 2 longitudinal m+n Sub-regulatory signals.

[0059] Furthermore, the multiple sub-control signals pass through the grating coupler 15, and the grating coupler 15 couples the multiple sub-control signals to generate an optical coding pattern.

[0060] Specifically, the transverse sub-control signal and the longitudinal sub-control signal enter the reflector in pairs, and the two sub-control signals in each reflector are coupled by the grating coupler 15 to generate 2 n+m A light beam outputs an optically coded pattern.

[0061] Furthermore, the optical coding pattern is projected onto the surface of the object to be measured by a projector, which may be a lens or other device.

[0062] The coding value of each pixel in the optical coding pattern is determined by the pixel values ​​at the corresponding positions on all the coded images.

[0063] In a specific implementation, the laser emits a 1550nm laser and is incident on a silicon waveguide SOI (Silicon On Insulator) structure two-dimensional phased array chip. The optical signal is divided into two equal-power optical signals by the first beam splitter 12 (DC / MMI / Y). The two optical signals pass through the transverse modulation module and the longitudinal modulation module respectively. In the transverse modulation module, the optical signal passes through n-level equal-power beam splitters to generate 2 n The light signal is modulated in the longitudinal direction by an n-level equal power beam splitter to generate 2 n Considering the high refractive index of silicon waveguide, the coupling crosstalk between adjacent waveguides can be ignored when the waveguide spacing of each channel is 2um.

[0064] Each light beam passes through a cross electrode as a phase shifter 131, and a preset phase control voltage is applied to the phase shifter 131 through a control unit to independently adjust the refractive index of each channel and output a first control signal. n+1 Compared with the conventional two-dimensional OPA, which uses 2 phase shifters, n*n Phase shifters can effectively reduce modulation power consumption. Each light beam passes through an optical amplifier 132, and a preset amplitude control voltage is applied to the optical amplifier 132 through a control unit to independently adjust the amplification gain of each channel and output a control signal. The control signal in each channel in the horizontal and vertical directions passes through 2 n A second beam splitter 14 (DC / MMI / Y) is used to generate 2n The horizontal and vertical beams are 2 2n The horizontal sub-control signal and the vertical sub-control signal enter the reflector in pairs, and the two sub-control signals in each reflector are coupled by the grating coupler 15 (MMI / Y) to generate 2 2n The projector projects the optical coding pattern onto the surface of the object in sequence.

[0065] For example, when the phase difference between adjacent waveguides in the control row and column is the same and the maximum is 2π, the maximum deflection angle of the light beam is 50.8°. By adjusting the phase difference of the waveguide array by voltage, a complex specified light spot pattern can be generated within 50.8° in the horizontal and vertical directions, thereby generating a specific high-precision optical coding pattern.

[0066] In this implementation, the phase and amplitude are controlled by the control unit, and the dynamic adjustment of the light beam can be achieved through current control within nanoseconds without the need for mechanical moving parts. By changing the phase and intensity of each phased array unit, the shape and direction of the light beam can be quickly adjusted to meet the measurement requirements of different objects to be measured.

[0067] The acquisition module 2 is aimed at the surface of the object to be measured, collects the reflected coded light on the surface of the object to be measured, obtains the intensity information and position distribution information of the light spot in the reflected coded light, obtains the reflected coded pattern, and sends the reflected coded pattern to the control module 3.

[0068] Specifically, the optical coding image is modulated by the topographic structure of the surface of the object to be measured, the light stripes are shifted, and the acquisition module 2 acquires the modulated reflection coding pattern.

[0069] The control module 3 receives the reflection coding pattern, decodes the reflection coding pattern, extracts the coding value, and calculates the characteristic information of the object to be measured based on the coding value. The characteristic information of the object to be measured includes the coordinate information of the surface of the object to be measured.

[0070] Specifically, the control module 3 decodes the reflection coding pattern using a trained neural network algorithm to extract a unique coding value. Exemplarily, the neural network algorithm includes a convolutional neural network, a Transformer-based network structure, and the like.

[0071] Furthermore, the triangular geometric relationship between the optical phased array module 1, the acquisition module 2 and the object to be measured is obtained, and the three-dimensional coordinates of the object to be measured are calculated. Finally, the internal and external parameters of the projector of the optical phased array module 1 and the acquisition module 2 are calibrated to achieve three-dimensional detection of the surface morphology structure of the object to be measured.

[0072] Further, the control module 3 adjusts the preset control instructions based on the three-dimensional coordinates of the object to be measured, uses the optical phased array module 1 to control the phase and amplitude according to the adjusted preset control instructions, generates the optical coding pattern again, and the control module 3 calculates the three-dimensional coordinates of the object to be measured again. After calculating the three-dimensional coordinates multiple times, the detection result is comprehensively determined.

[0073] Among them, there may be detection errors or the current phase and amplitude may not be suitable for detecting the object. Adjust the preset control instructions multiple times and perform multiple tests to improve the detection accuracy and reduce the impact of errors on the detection results.

[0074] In another implementation, the neural network algorithm is trained and tested before performing three-dimensional detection.

[0075] Specifically, the control module 3 generates random phase control instructions and random amplitude control instructions for multiple times, the optical phased array module 1 controls the optical signal based on the random phase control instructions and the random amplitude control instructions, generates a training coding pattern, and projects the training coding pattern onto the surface of the standard object to generate training reflection coding light, the acquisition module 2 acquires the training reflection coding light, obtains the training reflection coding pattern, and sends the training reflection coding pattern to the control module 3; the control module 3 decodes the training reflection coding pattern using a neural network algorithm, extracts the training coding value, and compares and studies the training coding pattern and the training reflection coding pattern, adjusts the training coding value, and trains the neural network algorithm. After the training is completed, the trained neural network algorithm is tested using a test set.

[0076] In this implementation, the coding pattern is decoded based on a machine learning algorithm to improve decoding accuracy and further improve the accuracy of object detection. When detecting objects with complex surfaces or large reflectivity changes, more accurate, efficient and robust decoding can be achieved.

[0077] According to an embodiment of the present invention, an embodiment of a structured light three-dimensional detection method based on optical phased array encoding is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0078] In this embodiment, a structured light 3D detection method based on optical phased array coding is provided, which can be used in the above-mentioned structured light 3D detection system based on optical phased array coding. Figure 1 and Figure 3 , Figure 3is a flow chart of a structured light three-dimensional detection method based on optical phased array coding according to an embodiment of the present invention. It should be noted that if there are substantially the same results, this embodiment is not limited to Figure 3 The process sequence shown is limited. Figure 3 As shown, the process includes the following steps:

[0079] Step S301, generating a preset control instruction.

[0080] The control module generates a preset control instruction based on the empirical value or the characteristic information of the object to be measured calculated at a historical moment. The preset control instruction includes a preset phase control voltage and a preset amplitude control voltage.

[0081] In one implementation, the control module generates a preset control instruction according to the measurement requirements and the surface characteristics of the object to be measured, wherein the surface characteristics of the object to be measured include the reflectivity change and geometric shape characteristics of the object.

[0082] In another implementation, the control module adjusts the preset control instructions for the previous n times according to the characteristic information of the object to be measured obtained by previous n calculations to generate new preset control instructions.

[0083] Step S302, phase and amplitude control the optical signal based on preset control instructions to generate an optical coding pattern, and project the optical coding pattern onto the surface of the object to be tested so that the object to be tested reflects the optical coding pattern to generate reflected coded light.

[0084] The light source in the optical phased array module transmits the optical signal to the two-dimensional OPA, and then transmits it to the pixel point through the power beam splitting route. After the pixel point receives the optical signal, the control unit of the optical phased array module performs phase and amplitude control on the optical signal based on the preset control instructions.

[0085] The control unit integrates hundreds to thousands of tiny optical elements, each of which includes a phase shifter and an optical amplifier. The control module controls the horizontal and vertical optical signals to perform phase modulation on the phase shifter through a preset phase control voltage, and controls the horizontal and vertical optical signals to perform amplitude modulation on the optical amplifier through a preset amplitude control voltage, thereby generating a high-precision optical coding pattern. Figure 1 As shown, the image on the left side of the optical phased array module is the initially generated optical coding pattern.

[0086] See also Figure 1 , the projector in the optical phased array module projects the modulated optical coding pattern onto the surface of the object to be measured.

[0087] It can be understood that by adjusting the preset phase control voltage and the preset amplitude control voltage, the phase and amplitude can be controlled, and the position distribution and intensity distribution of the light spot in the optical coding pattern can be indirectly adjusted, and finally the generated optical coding pattern can be adjusted. Different optical coding patterns can adapt to different measurement requirements and object surface characteristics.

[0088] Due to the influence of the surface morphology of the object to be tested, the light pattern in the optical coding pattern is modulated, such as the light stripes are offset or discontinuous. The degree of light stripe offset and whether it is discontinuous are related to the morphology of the object to be tested. The object to be tested reflects the modulated light beam to generate reflected coded light.

[0089] Step S303, collecting reflected coded light to obtain a reflected coded pattern, and sending the reflected coded pattern to a control module.

[0090] See also Figure 1 The acquisition module uses a high-speed camera or sensor to collect the reflected coded light reflected from the surface of the object to be tested. The intensity distribution information and position distribution information of the light spot in the reflected coded light are collected to generate a reflected coded pattern. Figure 1 As shown, the image on the right side of the acquisition module is the reflective coding pattern modulated by the object to be measured. Comparing the reflective coding pattern with the optical coding pattern, part of the light stripes in the reflective coding pattern are offset, and the offset light stripes can reflect the morphological characteristics of the object to be measured.

[0091] The acquisition module sends the acquired reflection coding pattern to the control module.

[0092] Step S304: decode the reflected coding pattern, extract the coding value, and calculate the characteristic information of the object to be measured based on the coding value.

[0093] The control module decodes the reflected coding pattern through the trained neural network algorithm, obtains the coding value through decoding, and calculates the three-dimensional coordinates of the object to be measured based on the triangular geometric relationship between the optical phased array module, the acquisition module and the object to be measured. Finally, the internal and external parameters of the projector and the acquisition module of the optical phased array module are calibrated to realize the three-dimensional detection of the surface morphology structure of the object to be measured.

[0094] Furthermore, the calculated three-dimensional coordinate information of the object to be measured can be used for shape analysis, dimension measurement, quality control, high-precision material surface detection, etc. of the object to be measured.

[0095] For example, in industrial manufacturing, it is used for product quality control and dimensional inspection, such as precision measurement of automotive parts, aerospace equipment, etc. In cultural heritage protection, it is used for three-dimensional digitization and virtual display to achieve accurate recording and restoration of cultural relics. In the medical field, it is used for bone and facial reconstruction, assisting surgical planning and treatment evaluation. In addition, in the fields of film and television production, virtual reality, etc., it is used for three-dimensional modeling and animation production to enhance visual effects and user experience.

[0096] In this implementation, the present application uses an optical phased array module to perform dual modulation of the phase and amplitude of the optical signal according to preset control instructions, generates an optical coding pattern of a preset target, and solves the problem of being unable to adjust the structured light source. The present application can achieve dynamic adjustment of the light intensity distribution and phase distribution of the light beam by adjusting the preset control instructions, which can solve the problem that traditional line light sources cannot achieve rapid switching of multiple light modes. The characteristic information of the object to be measured is decoded and calculated based on the generated coded image, which can improve the flexibility and controllability of three-dimensional detection. At the same time, modulating the phase and amplitude separately can encode more three-dimensional information of the object to be measured, improving measurement accuracy and efficiency.

[0097] See also Figure 4 , Figure 4 is a schematic diagram of the structure of a computer device provided by an optional embodiment of the present invention, such as Figure 4 As shown, the computer device includes: one or more processors 10, a memory 20, and interfaces for connecting various components, including high-speed interfaces and low-speed interfaces. Various components are connected to each other using different buses for communication, and can be installed on a common mainboard or installed in other ways as needed. The processor can process the instructions executed in the computer device, including instructions stored in or on the memory to display the graphical information of the GUI on an external input / output device (such as, a display device coupled to the interface). In some optional embodiments, if necessary, multiple processors and / or multiple buses can be used together with multiple memories and multiple memories. Similarly, multiple computer devices can be connected, and each device provides some necessary operations (for example, as a server array, a group of blade servers, or a multi-processor system). Figure 4 A processor 10 is taken as an example.

[0098] The processor 10 may be a central processing unit, a network processor or a combination thereof. The processor 10 may further include a hardware chip. The hardware chip may be a dedicated integrated circuit, a programmable logic device or a combination thereof. The programmable logic device may be a complex programmable logic device, a field programmable gate array, a general purpose array logic or any combination thereof.

[0099] The memory 20 stores instructions executable by at least one processor 10, so that the at least one processor 10 executes the method shown in the above embodiment.

[0100] The memory 20 may include a program storage area and a data storage area, wherein the program storage area may store an operating system, an application required for at least one function; the data storage area may store data created according to the use of the computer device, etc. In addition, the memory 20 may include a high-speed random access memory, and may also include a non-transient memory, such as at least one disk storage device, a flash memory device, or other non-transient solid-state storage device. In some optional embodiments, the memory 20 may optionally include a memory remotely arranged relative to the processor 10, and these remote memories may be connected to the computer device via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0101] The memory 20 may include a volatile memory, such as a random access memory; the memory may also include a non-volatile memory, such as a flash memory, a hard disk or a solid state drive; the memory 20 may also include a combination of the above types of memory.

[0102] The computer device also includes an input device 30 and an output device 40. The processor 10, the memory 20, the input device 30 and the output device 40 may be connected via a bus or other means. Figure 4 The example of connecting through bus is taken in the following.

[0103] The input device 30 can receive input digital or character information, and generate key signal input related to the user settings and function control of the computer device, such as a touch screen, a keypad, a mouse, a track pad, a touch pad, an indicator bar, one or more mouse buttons, a trackball, a joystick, etc. The output device 40 may include a display device, an auxiliary lighting device (e.g., an LED) and a tactile feedback device (e.g., a vibration motor), etc. The above-mentioned display device includes but is not limited to a liquid crystal display, a light emitting diode, a display and a plasma display. In some optional embodiments, the display device can be a touch screen.

[0104] The embodiment of the present invention also provides a computer-readable storage medium. The method according to the embodiment of the present invention can be implemented in hardware, firmware, or can be implemented as a computer code that can be recorded in a storage medium, or can be implemented as a computer code that is originally stored in a remote storage medium or a non-temporary machine-readable storage medium and will be stored in a local storage medium through a network download, so that the method described herein can be stored in such software processing on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. Among them, the storage medium can be a magnetic disk, an optical disk, a read-only storage memory, a random access memory, a flash memory, a hard disk or a solid-state hard disk, etc.; further, the storage medium can also include a combination of the above types of memories. It can be understood that a computer, a processor, a microprocessor controller, or programmable hardware includes a storage component that can store or receive software or computer code. When the software or computer code is accessed and executed by a computer, a processor, or hardware, the method shown in the above embodiment is implemented.

[0105] A part of the present invention may be applied as a computer program product, such as a computer program instruction, which, when executed by a computer, can call or provide the method and / or technical solution according to the present invention through the operation of the computer. Those skilled in the art should understand that the existence of the computer program instruction in a computer-readable medium includes, but is not limited to, a source file, an executable file, an installation package file, etc., and accordingly, the way in which the computer program instruction is executed by the computer includes, but is not limited to: the computer directly executes the instruction, or the computer compiles the instruction and then executes the corresponding compiled program, or the computer reads and executes the instruction, or the computer reads and installs the instruction and then executes the corresponding installed program. Here, the computer-readable medium may be any available computer-readable storage medium or communication medium accessible to the computer.

[0106] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A structured light three-dimensional detection system based on optical phased array coding, characterized in that: The system includes an optical phased array module, an acquisition module and a control module, wherein the control module is connected to the optical phased array module and the acquisition module, wherein: The optical phased array module is used to perform phase control and amplitude control on the optical signal based on a preset control instruction to generate an optical coding pattern, and project the optical coding pattern onto the surface of the object to be measured, so that the object to be measured reflects the optical coding pattern to generate reflected coded light; The collection module is used to collect the reflected coded light to obtain a reflected coded pattern, and send the reflected coded pattern to the control module; The control module is used to generate the preset control instruction, decode the reflection coding pattern, extract the coding value, and calculate the characteristic information of the object to be measured based on the coding value.

2. The structured light three-dimensional detection system based on optical phased array coding according to claim 1, characterized in that: The optical phased array module includes a light source, a first beam splitter, a second beam splitter, a plurality of control units, a grating coupler and a projector, wherein: The light source is used to output the light signal; The first beam splitter is used to perform beam splitting processing on the optical signal to generate multiple sub-optical signals; The control unit is used to perform phase control and amplitude control on the sub-optical signal based on the preset control instruction to generate a corresponding control signal; The second beam splitter is used to perform beam splitting processing on the control signal to generate multiple sub-control signals; The grating coupler is used to couple the multiple sub-regulation signals to generate the optical coding pattern; The projector is used to project the optical coding pattern onto the surface of the object to be measured.

3. The structured light three-dimensional detection system based on optical phased array coding according to claim 2, characterized in that: The control unit includes a phase shifter and an optical amplifier, and the preset control instruction includes a preset phase control voltage and a preset amplitude control voltage, wherein: The phase shifter is used to perform phase control on the sub-optical signal based on the preset phase control voltage to generate a first control signal; The optical amplifier is used to perform amplitude control on the first control signal based on the preset amplitude control voltage to generate the control signal.

4. The structured light three-dimensional detection system based on optical phased array coding according to claim 3 is characterized in that: The phase shifter is used to adjust the refractive index of the sub-optical signal under the action of the preset phase control voltage, form a phase difference between adjacent sub-optical signals, and generate a first control signal; The optical amplifier is used to determine the amplification gain ratio of the first control signal under the effect of the preset amplitude control voltage, and adjust the amplitude of the first control signal based on the amplification gain ratio to generate the control signal, wherein: I2=G·I1; The I2 is the amplitude of the control signal, the G is the amplification gain ratio, and the I1 is the amplitude of the first control signal.

5. The structured light three-dimensional detection system based on optical phased array coding according to claim 1, characterized in that: The control module is further used to decode the reflection coding pattern using a trained neural network algorithm to extract the coding value; Acquiring positional relationship information among the optical phased array module, the acquisition module and the object to be measured; The characteristic information of the object to be detected is calculated based on the code value and the position relationship information.

6. The structured light three-dimensional detection system based on optical phased array coding according to claim 5, characterized in that: The optical phased array module is further used to regulate the optical signal based on the training regulation instruction to generate a training coding pattern, and project the training coding pattern onto the surface of the standard object so that the standard object reflects the training coding pattern to generate training reflected coded light, wherein the training regulation instruction includes a random phase regulation instruction and a random amplitude regulation instruction; The acquisition module is further used to acquire the training reflection coded light to obtain a training reflection coded pattern, and send the training reflection coded pattern to the control module; The control module is also used to generate the training control instructions; it is also used to use a neural network algorithm to decode the training reflection coding pattern, extract the training coding value, compare and study the training coding pattern and the training reflection coding pattern, adjust the training coding value, and train the neural network algorithm.

7. A structured light three-dimensional detection method based on optical phased array coding, characterized in that: The structured light three-dimensional detection system based on optical phased array coding according to any one of claims 1 to 6 comprises: Generate preset control instructions; Performing phase control and amplitude control on the optical signal based on the preset control instruction to generate an optical coding pattern, and projecting the optical coding pattern onto the surface of the object to be measured, so that the object to be measured reflects the optical coding pattern to generate reflected coded light; collecting the reflected coded light to obtain a reflected coded pattern, and sending the reflected coded pattern to the control module; The reflective coding pattern is decoded to extract the coding value, and the characteristic information of the object to be measured is calculated based on the coding value.

8. A computer device, characterized in that: include: A memory and a processor, wherein the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the structured light three-dimensional detection method based on optical phased array coding as described in claim 7 by executing the computer instructions.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a computer to execute the structured light three-dimensional detection method based on optical phased array encoding according to claim 7.

10. A computer program product, characterized in that It includes computer instructions, and the computer instructions are used to enable a computer to execute the structured light three-dimensional detection method based on optical phased array coding as described in claim 7.

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