Light projector and three-dimensional reconstruction system

Abstract

The embodiment of the utility model provides a light projector and a three-dimensional reconstruction system. Wherein the light projector comprises a light source for emitting a laser beam; the light source comprises a light-emitting panel, light source areas in different arrangement modes are arranged on the light-emitting panel, and the light-emitting panel at least comprises a first light source area and a second light source area. Wherein the first light source area is configured to be used for forming a speckle pattern through projection, and the second light source area is configured to be used for forming a stripe pattern through projection.

Description

Technical Field

[0001] Embodiments of the present application relate to the field of three-dimensional reconstruction technology. More specifically, embodiments of the present application relate to a light projector and a three-dimensional reconstruction system. Background Art

[0002] Three-dimensional reconstruction refers to establishing a mathematical model suitable for computer processing for a three-dimensional object or scene. Currently, three-dimensional reconstruction technology is mainly achieved through a three-dimensional scanner. The scanner obtains point cloud data on the surface by scanning an object and constructs a digital model of the actual object in the virtual world through calculation and processing. To improve the accuracy of three-dimensional reconstruction, denser data points need to be collected. In traditional technologies, three-dimensional reconstruction is mainly carried out by combining speckle and fringe projection. This usually requires setting up a structured light projector and a speckle projector to project fringe and speckle structured light respectively, and image acquisition is performed by a binocular camera. This method requires multiple projectors to work together, which not only increases the complexity of the entire three-dimensional reconstruction system but also raises the production cost and occupied space of three-dimensional reconstruction equipment. Summary of the Utility Model

[0003] The purpose of the present application is to provide a new technical solution for a light projector and a three-dimensional reconstruction system.

[0004] In a first aspect, the present application provides a light projector. The light projector includes:

[0005] including a light source for emitting a laser beam;

[0006] The light source includes a light-emitting panel, on which light source regions with different arrangement modes are provided, and at least includes a first light source region and a second light source region;

[0007] wherein, the first light source region is configured to be able to project and form a speckle pattern, and the second light source region is configured to be able to project and form a fringe pattern.

[0008] Optionally, the light source regions with different arrangement modes on the light-emitting panel can be independently lit in zones.

[0009] Optionally, the first light source region is a strip-shaped light-emitting region, which includes at least one strip-shaped light-emitting module and can be used to obtain a fringe pattern;

[0010] The second light source region is a hole-shaped light-emitting region, which includes a plurality of light-emitting holes arranged in a set manner and can be used to obtain a speckle pattern.

[0011] Optionally, both the first light source region and the second light source region are hole-shaped light-emitting regions;

[0012] Among them, the first light source area includes a first light-emitting hole array, the second light source area includes a second light-emitting hole array, the light-emitting holes in the first light-emitting hole array and the second light-emitting hole array have two different hole pitches, and the light-emitting holes in the first light-emitting hole array are arranged in a strip structure.

[0013] Optionally, there is a first hole pitch between the light-emitting holes on the first light-emitting hole array, and a second hole pitch between the light-emitting holes on the second light-emitting hole array;

[0014] The first hole pitch is smaller than the target hole pitch, so that the speckles obtained by diffraction of the light-emitting holes on the first light-emitting hole array will overlap with each other, thereby obtaining a fringe pattern;

[0015] The second hole pitch is larger than the target hole pitch, so that the speckles obtained by diffraction of the light-emitting holes on the second light-emitting hole array will not overlap, thereby obtaining a speckle pattern.

[0016] Optionally, the relationship between the hole pitch AB between the light-emitting holes on the first light-emitting hole array and the distance A'B' between the speckles in the corresponding speckle pattern is AB:A'B' = f:(v - f); where f is the focal length of the light projector, and v is the projection distance of the light projector.

[0017] Optionally, the light projector further includes a control module for controlling the lighting states of different light source areas on the light-emitting panel to realize the switching between the speckle image mode and / or the fringe image mode.

[0018] Optionally, the arrangement of the light-emitting holes on the hole-shaped light-emitting area includes regular arrangement or random arrangement.

[0019] Optionally, the light projector further includes a diffractive optical element, and the diffractive optical element is arranged on the light-emitting side of the light-emitting panel;

[0020] The pattern formed on the projection surface by the laser beam emitted by the light-emitting panel after passing through the diffractive optical element is a regular splicing pattern or a misaligned splicing pattern.

[0021] Optionally, the first light source area and the second light source area are each set to at least one; the first light source area and the second light source area are arranged on the surface of the light-emitting panel in a set manner.

[0022] In a second aspect, the present application provides a three-dimensional reconstruction system, and the three-dimensional reconstruction system includes:

[0023] A light projector as described in the first aspect; and

[0024] A camera.

[0025] The beneficial effects of the present application are as follows:

[0026] The embodiment of the present application provides a light projector, which realizes the dual functions of a single projector capable of projecting both speckle patterns and stripe patterns. This design helps to simplify the structural composition of a three-dimensional reconstruction system, streamline multiple light projectors required in the traditional solution to a single light projector, and greatly reduce the equipment cost and occupied space. The light projector provided by the present application not only optimizes resource allocation, but also promotes a significant improvement in the overall performance of the three-dimensional reconstruction system, demonstrating excellent economic benefits and space utilization rate.

[0027] Through the following detailed description of the exemplary embodiments of the present specification with reference to the accompanying drawings, other features and advantages of the present specification will become clear. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The drawings incorporated in and constituting a part of this specification illustrate embodiments of the present specification and, together with the description thereof, are used to explain the principles of the present specification.

[0029] Figure 1 One of the schematic structural diagrams of the light-emitting panel provided by the embodiment of the present application;

[0030] Figure 2 Another schematic structural diagram of the light-emitting panel provided by the embodiment of the present application;

[0031] Figure 3 Another schematic structural diagram of the light-emitting panel provided by the embodiment of the present application;

[0032] Figure 4 Another schematic structural diagram of the light-emitting panel provided by the embodiment of the present application;

[0033] Figure 5 Another schematic structural diagram of the light-emitting panel provided by the embodiment of the present application;

[0034] Figure 6 is Figure 4 and Figure 5 One of the design principle diagrams of the shown light-emitting panel;

[0035] Figure 7 is Figure 4 and Figure 5 Another design principle diagram of the shown light-emitting panel;

[0036] Figure 8 is Figure 4 and Figure 5 Another design principle diagram of the shown light-emitting panel;

[0037] Figure 9 One of the patterns projected by the light projector provided by the embodiment of the present application;

[0038] Figure 10 This is the second pattern projected by the light projector provided in the embodiment of the present application;

[0039] Figure 11 This is the third pattern projected by the light projector provided in the embodiment of the present application.

[0040] Explanation of reference numerals:

[0041] 1. Light-emitting panel; 11. First light source area; 12. Second light source area. Detailed implementation manners

[0042] Now, various exemplary embodiments of the present application will be described in detail with reference to the accompanying drawings. It should be noted that: unless otherwise specifically stated, the relative arrangements of components and steps, numerical expressions, and numerical values set forth in these embodiments do not limit the scope of the present application.

[0043] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way a limitation on the present application or its application or use.

[0044] Techniques and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, such techniques and devices should be regarded as part of the specification.

[0045] In all the examples shown and discussed herein, any specific values should be construed as merely exemplary and not as a limitation. Thus, other examples of the exemplary embodiments may have different values.

[0046] It should be noted that: like reference numerals and letters denote like items in the following drawings, and thus, once an item is defined in one drawing, further discussion thereof in subsequent drawings is not required.

[0047] Next, with reference to the accompanying drawings, the light projector and the three-dimensional reconstruction system provided in the embodiments of the present application will be described in detail.

[0048] According to an embodiment of the present application, a light projector is provided. The light projector includes a light source for emitting a laser beam; the light source includes a light-emitting panel 1, on which light source areas with different arrangement manners are provided, and at least includes a first light source area 11 and a second light source area 12, see Figures 1 to 5 ; wherein, the first light source area 11 is configured to be capable of projecting and forming a speckle pattern, and the second light source area 12 is configured to be capable of projecting and forming a fringe pattern.

[0049] The light projector provided by the embodiments of the present application integrates the functions of speckle projection and fringe projection into a single light projector. In other words, the functions of speckle pattern projection and fringe pattern projection are simultaneously achieved by one light projector. In this way, in a three-dimensional reconstruction system (or three-dimensional reconstruction device) for example, the number of light projectors used can be reduced, thereby saving equipment costs and space.

[0050] Light projectors play an important role in three-dimensional reconstruction systems. They mainly project structured light (such as speckles or fringe patterns) onto the object to be measured, and the camera captures the deformation of this structured light on the object surface, thereby obtaining the three-dimensional information of the object. However, existing light projectors still have some defects in practical applications. For example, in a traditional three-dimensional reconstruction system, in order to simultaneously project speckles and fringes, two independent light projectors need to be set up: one for projecting speckle patterns and the other for projecting fringe patterns. This configuration undoubtedly increases the cost of the system; moreover, due to the need for two light projectors, the overall size and space occupancy of the system will also increase accordingly, which is a significant challenge for application scenarios with limited space.

[0051] To overcome the above defects, the embodiments of the present application propose a new design scheme for light projectors, that is, integrating the speckle projection function and the fringe projection function into a single light projector, thereby achieving cost savings and reduced space occupancy.

[0052] Specifically, the light projector provided by the embodiments of the present application can bring the following technical effects:

[0053] (1) Cost and space savings: Traditional three-dimensional reconstruction systems require both a structured light projector and a speckle projector. Among them, the structured light projector is used to project fringes, and the speckle projector is used to project speckle patterns. However, the technical solution of the present application integrates two different arranged light source regions (the first light source region 11 and the second light source region 12) in one light projector, see Figures 1 to 5 , to achieve the function that a single light projector can simultaneously project speckle patterns and fringe patterns. When applied to a three-dimensional reconstruction system, it not only reduces the number of light projectors required, but also significantly saves costs and space occupancy.

[0054] (2) Simplified system design: Since the speckle projection function and the fringe projection function are integrated into one light projector, when it is applied to a three-dimensional reconstruction system for example, the overall structural design of the three-dimensional reconstruction system can be simplified. This not only reduces the complexity of the three-dimensional reconstruction system, but also improves the reliability and stability of the three-dimensional reconstruction system; at the same time, it also facilitates subsequent maintenance and upgrade work.

[0055] (3) Improve data acquisition efficiency: Since a single light projector can be used to project both speckle patterns and fringe patterns, when applied to, for example, a three-dimensional reconstruction system, it helps to improve the overall operating efficiency of the three-dimensional reconstruction system. During the three-dimensional reconstruction process, the density and accuracy of data acquisition directly affect the quality of the final model. The design of this application can quickly and efficiently complete data acquisition by flexibly switching between the speckle mode and the fringe mode on the same light projector, thereby improving the accuracy and efficiency of three-dimensional reconstruction.

[0056] In addition, the first light source area 11 and the second light source area 12 on the light-emitting panel 1 can be used independently or in combination according to actual needs. For example, in scenarios that require high-precision three-dimensional reconstruction, both the speckle mode and the fringe mode can be enabled simultaneously to obtain richer point cloud data; while in scenarios with low requirements for spatial resolution, the speckle mode or the fringe mode can be selected for independent use to reduce costs and energy consumption.

[0057] The embodiment of this application provides a light projector, which realizes the dual functions of a single projector capable of projecting both speckle patterns and fringe patterns. This design helps to simplify the structural composition of systems such as three-dimensional reconstruction systems, reducing the multiple light projectors required in traditional solutions to a single light projector, greatly reducing equipment costs and occupied space. The light projector provided by this application not only optimizes resource allocation, but also significantly improves the overall performance of the three-dimensional reconstruction system, demonstrating excellent economic benefits and space utilization.

[0058] In some examples of this application, see Figures 1 to 5 , the light source areas with different arrangement modes on the light-emitting panel 1 can be independently lit in zones.

[0059] In this example of this application, different arrangement modes of light source areas are designed on the light-emitting panel 1 of the light source, and these light source areas can be independently lit in zones to achieve the functions of multiple modes: such as the speckle mode, the fringe mode, or the combined speckle and fringe mode.

[0060] In traditional technologies, in order to project speckles and fringes, a speckle projector and a structured light projector are used separately. However, the light projector in this application realizes the function of a single light projector capable of simultaneously projecting speckles and fringes through the specially designed zone lighting technology on the light-emitting panel 1, thereby saving the cost of one light projector and reducing the space required for the equipment.

[0061] Since a single light projector is used to achieve multiple functions, the structure of the entire three-dimensional sensing system using this light projector can be simplified. This not only reduces the complexity and maintenance difficulty of the three-dimensional reconstruction system, but also improves the stability and reliability of the three-dimensional reconstruction system.

[0062] It should be noted that in the speckle pattern, the three-dimensional reconstruction system can obtain denser speckle point cloud data to capture the fine structure of the object; while in the fringe pattern, the three-dimensional reconstruction system can generate continuous fringe images to supplement the deficiencies of the speckle data, thereby enhancing the integrity and accuracy of the overall data.

[0063] In some examples of the present application, referring to Figures 1 to 3 , the first light source area 11 is a strip-shaped light-emitting area, which includes at least one strip-shaped light-emitting module and can be used to obtain a fringe pattern; the second light source area 12 is a hole-shaped light-emitting area, which includes a plurality of light-emitting holes arranged in a set manner and can be used to obtain a speckle pattern.

[0064] In this example of the present application, in combination with Figures 1 to 3 the design shown in, a specific implementation of the fringe + speckle light projector is demonstrated, in which a first light source area 11 and a second light source area 12 are provided on the light-emitting panel 1 of the light source. The following is an analysis of the technical effects of this example.

[0065] Regarding the first light source area 11 (i.e., the strip-shaped light-emitting area), it should be noted that when the first light source area 11 is used as the strip-shaped light-emitting area, only one can be provided on the light-emitting panel 1, referring to Figure 1 the structure shown, and the first light source area 11 only includes one strip-shaped light-emitting module.

[0066] However, the innovation of the present application is not limited to this. To meet the requirements of different scenarios and accuracies, the first light source area 11 further demonstrates its scalability and customization. Referring to Figure 2 and Figure 3 , on the light-emitting panel 1 of the light source, when the first light source area 11 is set to two or more, it can provide higher flexibility and data acquisition diversity for the three-dimensional reconstruction system. Each such area can either independently include one strip-shaped light-emitting module to achieve the basic fringe projection function; or be designed as a combination including multiple strip-shaped light-emitting modules, and through the collaborative work of the strip-shaped light-emitting modules, generate more complex and detailed fringe patterns to meet the requirements of high-precision three-dimensional reconstruction.

[0067] This design of the present application not only breaks the limitations of the functions of traditional light projectors, but also greatly improves the applicability and performance of the light projector. Whether it is the simple configuration of a single strip-shaped light-emitting module or the efficient integration of multiple modules, the first light source area 11 in the present application demonstrates its excellent adaptability and broad application prospects, providing users with richer and more flexible choices.

[0068] Generally speaking, the first light source area 11 provided in the embodiments of the present application is designed as a strip-shaped light-emitting area, which includes at least one strip-shaped light-emitting module. The main function of the first light source area 11 is to project a stripe pattern. When the first light source area 11 is lit, its strip-shaped light-emitting module can generate continuous or spaced strip-shaped light, and these strip-shaped lights projected onto an object will form a stripe pattern.

[0069] In this example of the present application, the first light source area 11 is a strip-shaped light-emitting area. Through a simple structural design, the strip-shaped light-emitting area can achieve the projection of a stripe pattern, reducing the structural complexity of the light projector. By projecting a stripe pattern, dense data points can be obtained on the surface of the object, improving the accuracy and precision of 3D reconstruction. Among them, the strip-shaped light-emitting module can be designed to be adjustable. By adjusting its brightness and / or arrangement mode, it can adapt to different application scenarios and reconstruction requirements.

[0070] Regarding the second light source area 12 (i.e., the hole-shaped light-emitting area):

[0071] In this example of the present application, see Figures 1 to 3 , the second light source area 12 is designed as a hole-shaped light-emitting area, which includes a plurality of light-emitting holes arranged in a set manner. The main function of the second light source area 12 is to project a speckle pattern. When these light-emitting holes are lit, the light emitted by each of them undergoes diffraction and interference to form a speckle pattern on the object.

[0072] The speckle pattern can be randomly distributed bright spots, which can provide rich feature information and further enhance the data quality of 3D reconstruction. In this example of the present application, the hole-shaped light-emitting area and the strip-shaped light-emitting area coexist in the same light projector, enabling the light projector to project two patterns, namely stripes and speckles, simultaneously to meet the requirements of different 3D reconstruction algorithms. By integrating the speckle and stripe projection functions into a single light projector, the number of required light projectors is reduced, thereby saving costs and space.

[0073] According to the description of this example of the present application, the light projector of the present application has two projection functions, namely the speckle mode and the stripe mode, and can flexibly adapt to different 3D reconstruction requirements. By combining the projection of stripes and speckle patterns, denser and more accurate point cloud data can be obtained, improving the accuracy and quality of 3D reconstruction. In practical applications, such as in the construction of a 3D reconstruction system, by reducing the number of light projectors, the system cost is significantly reduced and space is saved, which is beneficial to the promotion and application of the product.

[0074] In some examples of the present application, see Figure 4 and Figure 5, both the first light source area 11 and the second light source area 12 are hole-shaped light-emitting areas; wherein, the first light source area 11 includes a first light-emitting hole array, the second light source area 12 includes a second light-emitting hole array, the light-emitting holes in the first light-emitting hole array and the second light-emitting hole array have two different hole pitches, and the light-emitting holes in the first light-emitting hole array are arranged in a strip structure.

[0075] In this example of the present application, refer to Figure 4 and Figure 5 , both the first light source area 11 and the second light source area 12 adopt the design of hole-shaped light-emitting areas, and each has a unique layout of light-emitting hole arrays. In this regard, the specific technical effects are as follows.

[0076] In this example of the present application, by designing both the first light source area 11 and the second light source area 12 on the light-emitting panel 1 of the light source as hole-shaped light-emitting areas, and respectively configuring them as the first light-emitting hole array and the second light-emitting hole array, this projector can also simultaneously realize the functions of speckle projection and fringe projection within a single device. The specific analysis is as follows:

[0077] For the first light source area 11 and the second light source area 12, refer to Figure 4 and Figure 5 , the light-emitting holes in the first light-emitting hole array and the second light-emitting hole array have two different hole pitches, and this difference makes the projected speckle pattern and fringe pattern have different characteristics. By precisely controlling these hole pitches, the density of the speckles and fringes can be adjusted, so that more dense and accurate data can be collected during the three-dimensional reconstruction process. The increase in these data points will directly improve the accuracy and fineness of the three-dimensional model.

[0078] The design of different hole pitches allows users to selectively activate the light sources in specific areas according to specific needs. For example, when high-precision measurement is required, the light-emitting hole array with a smaller hole pitch can be selected to generate a fringe pattern; while in scenarios where the measurement accuracy requirement is relatively low, the light-emitting hole array with a larger hole pitch can be selected to generate a speckle pattern.

[0079] In some examples of the present application, refer to Figure 4 and Figure 5 , there is a first hole pitch between the light-emitting holes on the first light-emitting hole array, and there is a second hole pitch between the light-emitting holes on the second light-emitting hole array; refer to Figure 8 , the first hole pitch is smaller than the target hole pitch, so that the speckles diffracted by the light-emitting holes on the first light-emitting hole array will overlap with each other, thereby obtaining a fringe pattern; the second hole pitch is larger than the target hole pitch, so that the speckles diffracted by the light-emitting holes on the second light-emitting hole array will not overlap, thereby obtaining a speckle pattern.

[0080] See Figure 4 and Figure 5 In the solution shown, a first light source area 11 and a second light source area 12 are respectively arranged on the light-emitting panel 1 of the light source, and both the first light source area 11 and the second light source area 12 are hole-shaped light-emitting areas. Based on the foregoing examples, it can be seen that the arrangements of the light-emitting holes of the two are different.

[0081] In this example of the present application, for the first light source area 11, it adopts a first light-emitting hole array, and there is a first hole pitch between the light-emitting holes thereon. This first hole pitch (see the dotted line at the bottom shown in Figure 8 ) is specifically set to be smaller than the target hole pitch (see the dashed line in the middle shown in Figure 8 ). This design makes it that when the first light-emitting hole array is lit, the laser beams emitted by it will overlap with each other after diffraction on the surface of the object to be measured. Due to the overlapping effect, these speckles form a continuous fringe pattern visually, providing more dense data points for 3D reconstruction and helping to improve the accuracy and details of the reconstruction.

[0082] In this example of the present application, for the second light source area 12, it adopts a second light-emitting hole array, and there is a second hole pitch between the light-emitting holes thereon. This second hole pitch (see the solid line at the top shown in Figure 8 ) is greater than the target hole pitch (see the dashed line in the middle shown in Figure 8 ). Therefore, when the second light-emitting hole array is lit, the speckles formed on the surface of the object to be measured after the diffraction of the light emitted by it can maintain sufficient intervals and avoid overlapping with each other. The speckle pattern generated by this layout has rich feature points, can be effectively used for 3D reconstruction, and at the same time avoids data redundancy and increased processing complexity that may be caused by speckle overlap.

[0083] That is to say, on the light-emitting panel 1, by adjusting the hole pitch, the user can flexibly select to project a speckle or a fringe pattern to meet different measurement accuracy requirements. In high-precision measurement, the dense data points of the fringe pattern provide higher accuracy; while in scenarios with low precision requirements, the speckle pattern reduces the processing cost with its efficient feature point extraction ability.

[0084] In some examples of the present application, see Figure 6 shown, the relationship between the hole pitch AB between the light-emitting holes on the first light-emitting hole array and the distance A'B' between the speckles in its corresponding speckle pattern is AB:A'B' = f:(v - f); where f is the focal length of the light projector and v is the projection distance of the light projector.

[0085] Please continue to seeFigure 4 and Figure 5 In the solution shown, both the first light source area 11 and the second light source area 12 on the light-emitting panel 1 are hole-shaped light-emitting areas. The first light source area 11 includes a first light-emitting hole array, and the second light source area 12 includes a second light-emitting hole array. However, the light-emitting holes in the first light-emitting hole array and the second light-emitting hole array have two different hole pitches. It should be noted that in order for the first light source area 11 to project a stripe pattern, the hole pitch (i.e., the first hole gap) between the light-emitting holes thereon needs to be strictly designed. The specific analysis is as follows.

[0086] In this example provided in the present application, the calculation of the distance between speckles and the diameter of the light spot respectively follows the rigorous logic of geometric optics and Gaussian beam theory. First, based on the principle of geometric optics, the calculation method of the speckle pitch is clarified as: Refer to Figure 6 , the distance between adjacent light-emitting holes (referring to the first light source area 11) on the light-emitting panel 1 of the light source is denoted as AB (i.e., pitch), and the distance between the corresponding speckles in the speckle pattern is denoted as A'B'. They are closely related through the geometric relationship of the focal length (f) and the projection distance (v) of the light projector. The specific relationship is expressed as AB:A'B' = f:(v - f). This formula accurately describes the mapping relationship between the light source layout and the projection effect.

[0087] Furthermore, in order to precisely control the diameter of the light spot, the q-parameter transformation of the Gaussian beam and the Kogelnik law are introduced. In this process, refer to Figure 7 , first, the waist radius (w1) of the incident light and the radius (w2) of the outgoing light at the projection position are defined. At the same time, the influence of the distance (d1) from the light source to the lens, the projection distance (d2, which is the same as v here for consistency), and the focal length (f) are considered. Through the rigorous application of the Kogelnik law, the diameter of the light spot on the projection plane can be calculated. This calculation not only considers the divergence characteristics of the light beam but also ensures the precise matching of the light spot size and the projection system parameters.

[0088] Particularly importantly, when the diameter of the light spot in the speckle pattern is greater than the speckle pitch, multiple light spots will overlap, thus forming a continuous stripe pattern visually.

[0089] In summary, through precise geometric optics calculations and the application of Gaussian beam theory, the fine control of the speckle pitch and the light spot diameter is achieved, providing a solid theoretical basis and technical support for the application of projectors in fields such as three-dimensional reconstruction.

[0090] Please continue to refer to Figure 7 :

[0091] (1) The waist position of the incident light is at the light source, and the formula for the waist radius of the incident light is as follows: θ = λ / πw1, where θ is the divergence angle of the light source, in units of rad.

[0092] (2) The q-parameter of the input Gaussian beam waist: q(1) = (iπw1 2 ) / λ.

[0093] (3) The optical matrix from q1 to q2 is as follows:

[0094]

[0095] (4) Kogelnik's law

[0096]

[0097] In a specific example, the wavelength of the light source is 940 nm, its divergence angle θ is 22°, the focal length f of the light projector is 1.0 mm, and the distance v from the light source to the diffractive optical element (DOE, which is part of the light projector) is 1.03 mm. Refer to Figure 4 and Figure 5 the shown scheme. There are two types of light-emitting holes with different intervals on the light-emitting panel 1 of the light source. The large interval (the second hole pitch) is 20 μm, and the small interval (the first hole pitch) is 10 μm. Through relevant calculations, refer to Figure 8 , solid line > virtual image > dotted line, that is, the speckles diffracted by the light-emitting holes with large intervals will not

[0098] In some examples of the present application, the light projector further includes a control module for controlling the lighting states of different light source regions on the light-emitting panel to achieve the switching between the speckle image mode and / or the fringe image mode.

[0099] In this example of the present application, the design of the light projector is further optimized and enhanced. In particular, a key control module is introduced. This module plays a crucial role. It is responsible for precisely controlling the lighting states of different light source regions on the light-emitting panel 1. Through intelligent regulation, the control module can flexibly achieve seamless switching between the speckle image mode and the fringe image mode, or simultaneously display the mixed effects of both.

[0100] For example, when high-precision three-dimensional data needs to be collected, the control module can selectively light up the light-emitting hole array with a smaller hole pitch (such as the first hole pitch), so that the projected light spots overlap with each other to form a fringe pattern, or directly light up the strip-shaped light-emitting module to form a fringe pattern, thereby increasing the density of data points and improving the reconstruction accuracy. On the contrary, in occasions where the accuracy requirement is not high, the control module can activate the light-emitting hole array with a larger hole pitch (the second hole pitch) to generate a clear speckle pattern, which not only ensures the measurement efficiency but also reduces the complexity of data processing.

[0101] In addition, the introduction of the control module endows the light projector with a higher level of intelligence and stronger adaptability. Through preset algorithms or user-defined settings, the control module can automatically adjust the lighting mode of the light source area according to changes in the external environment or the user's immediate instructions, ensuring that the projected image always meets the requirements of measurement or recognition.

[0102] In some examples of the present application, the arrangement of the light-emitting holes on the hole-shaped light-emitting area includes regular arrangement or random arrangement.

[0103] Regarding the regularly arranged light-emitting holes:

[0104] From a technical effect perspective, the regularly arranged light-emitting holes can generate an ordered speckle pattern, and these speckles show a uniform distribution and predictable spacing on the projection plane. This regularity helps to perform accurate point cloud matching and calculation during the three-dimensional reconstruction process, thereby improving the accuracy and efficiency of the reconstruction.

[0105] From an application scenario perspective: applicable to scenarios with high precision requirements, such as precision industrial measurement, medical imaging, etc., the regularly arranged speckles can provide a more stable data basis.

[0106] Regarding the randomly arranged light-emitting holes:

[0107] From a technical effect perspective: the randomly arranged light-emitting holes will generate an irregular speckle pattern, and these speckles are more randomly distributed on the projection plane, reducing the periodicity of the pattern and reducing errors and interference caused by periodicity. Random arrangement helps to increase the robustness of the measurement and resist interference from external factors such as ambient light and object surface reflection.

[0108] From an application scenario perspective: applicable to three-dimensional reconstruction in complex environments or dynamic scenarios, such as outdoor scenarios, dynamic object capture, etc., the randomly arranged speckles can better adapt to these changes and provide stable and reliable measurement data.

[0109] In some examples of the present application, the light projector further includes a diffractive optical element (not shown in the figure), and the diffractive optical element is disposed on the light-emitting side of the light-emitting panel 1; seeFigures 9 to 11 The pattern formed on the projection surface by the laser beam emitted from the light-emitting panel 1 after passing through the diffractive optical element is a regular splicing pattern or a misaligned splicing pattern.

[0110] In this example of the present application, the diffractive optical element is placed on the light-emitting side of the light-emitting panel 1, and its main function is to further process and modulate the laser beam emitted from the light-emitting panel 1. Through the diffraction effect, the light beam can form complex patterns on the projection surface, and these patterns are crucial for data acquisition in the three-dimensional reconstruction process.

[0111] When the laser beam is processed by the diffractive optical element, a regularly spliced pattern can be formed on the projection surface, such as Figures 9 to 11 shown. The characteristic of this pattern is that the various parts show an orderly arrangement and splicing, which helps to perform accurate point cloud matching and calculation in the three-dimensional reconstruction process.

[0112] On the other hand, the diffractive optical element can also generate a misaligned splicing pattern. There is a certain misalignment or offset between the various parts of this pattern, thus increasing the complexity of the pattern. The misaligned splicing pattern shows higher robustness when dealing with complex environments or dynamic changes, and can effectively reduce errors caused by environmental interference or object movement.

[0113] Whether it is a regular splicing pattern or a misaligned splicing pattern, a high-density and high-precision light spot distribution can be formed on the projection surface. These light spots provide rich data points for three-dimensional reconstruction, which helps to improve the accuracy and precision of measurement.

[0114] The introduction of the diffractive optical element enables the light projector to generate different types of patterns according to actual needs. This flexibility enables the projector to be applicable to a variety of different application scenarios, and can demonstrate excellent performance from precision measurement to complex environment scanning.

[0115] In some examples of the present application, see Figures 1 to 5 wherein the first light source region 11 and the second light source region 12 are each set to at least one; the first light source region 11 and the second light source region 12 are arranged on the surface of the light-emitting panel 1 in a set manner.

[0116] For example, see Figure 1 wherein the light-emitting panel 1 of the light source includes two regions: a first light source region 11 and a second light source region 12; wherein, the first light source region 11 is a strip-shaped light-emitting region, which includes a strip-shaped light-emitting module and can be used to obtain a strip-shaped pattern; the second light source region 12 is a hole-shaped light-emitting region, which has a plurality of regularly arranged light-emitting holes and can be used to obtain a speckle pattern.

[0117] For example, seeFigure 2 , the light-emitting panel 1 of the light source includes two regions: a first light source region 11 and a second light source region 12; wherein, the first light source region 11 is a strip-shaped light-emitting region, and is provided in three, each of the first light source regions 11 includes a strip-shaped light-emitting module, which can be used to obtain a strip pattern; the second light source region 12 is a hole-shaped light-emitting region, and is provided in two, each of the second light source regions 12 includes a plurality of regularly arranged light-emitting holes, which can be used to obtain a speckle pattern. It should be noted that one second light source region 12 is provided between two adjacent first light source regions 11.

[0118] For example, see Figure 3 , the light-emitting panel 1 of the light source includes two regions: a first light source region 11 and a second light source region 12; wherein, the first light source region 11 is a strip-shaped light-emitting region, and is provided in two, each of the first light source regions 11 includes a strip-shaped light-emitting module, which can obtain a strip pattern; the second light source region 12 is a hole-shaped light-emitting region, and is provided in two, each of the second light source regions 12 includes a plurality of regularly arranged light-emitting holes, which can be used to obtain a speckle pattern. It should be noted that one horizontally placed first light source region 11 is provided between two adjacent second light source regions 12, and one longitudinally arranged first light source region 11 is provided on one side (left side) of the two second light source regions 12.

[0119] For example, see Figure 4 , the light-emitting panel 1 of the light source includes two regions: a first light source region 11 and a second light source region 12; both the first light source region 11 and the second light source region 12 are hole-shaped light-emitting regions, and one of each of the first light source region 11 and the second light source region 12 is provided, and the light-emitting holes in the first light source region 11 are arranged in a strip shape. The first hole pitch between the light-emitting holes in the first light source region 11 is smaller than the second hole pitch between the light-emitting holes in the second light source region 12. Among them, the first light source region 11 can be used to obtain a strip pattern, and the second light source region 12 can be used to obtain a speckle pattern.

[0120] For example, see Figure 5 , different from the structure shown in Figure 4 , one horizontally arranged first light source region 11 (the plurality of light-emitting holes included therein are arranged in a strip structure) is provided between two adjacent second light source regions 12, and one longitudinally arranged first light source region 11 (the plurality of light-emitting holes included therein are arranged in a strip structure) is provided on one side (left side) of the two second light source regions 12. Among them, the first light source region 11 can be used to obtain a strip pattern, and the second light source region 12 can be used to obtain a speckle pattern.

[0121] The core of this application lies in designing a light projector that integrates the functions of speckle and stripe projection. Its advantages are that it significantly reduces the equipment cost by streamlining the requirement for multiple light projectors to a single device, and at the same time greatly saves space resources, making the overall layout of the 3D reconstruction system more compact and efficient. This design not only helps to simplify the structure of the 3D reconstruction system and reduce the complexity, but also significantly improves the reliability and stability of the system. Particularly crucial is that by carefully optimizing the layout and lighting strategy of the light source area and combining diffractive optical elements, the light projector provided in the embodiments of this application can generate more dense and accurate speckle and stripe patterns on the projection surface, thereby greatly improving the accuracy of 3D reconstruction. In addition, this light projector has a high degree of flexibility and can easily achieve independent or combined switching between speckle and stripe image modes to flexibly meet the requirements of diverse application scenarios.

[0122] According to another embodiment of this application, a 3D reconstruction system is also provided. The 3D reconstruction system includes the light projector and a camera as described above.

[0123] The 3D reconstruction system of this application involves a 3D reconstruction method in application. The 3D reconstruction method includes the following steps S1 to step S5:

[0124] Step S1: Provide a light projector; wherein, the light projector includes a light source, the light source includes a light-emitting panel, and different arranged light source areas are provided on the light-emitting panel, which at least include a first light source area and a second light source area. The first light source area can be used to project and form a speckle pattern, and the second light source area can be used to project and form a stripe pattern;

[0125] Step S2: Select the first light source area and / or the second light source area on the light-emitting panel to be lit to form a speckle pattern and / or a stripe pattern on the projection surface;

[0126] Step S3: Project the speckle pattern and / or the stripe pattern onto the object to be measured;

[0127] Step S4: Capture images of the speckle pattern and / or the stripe pattern projected onto the object to be measured through at least one camera;

[0128] Step S5: Perform 3D reconstruction based on the captured images to generate a 3D model of the object to be measured.

[0129] In the above embodiments, the differences between the various embodiments are mainly described. As long as the different optimization features between the various embodiments are not contradictory, they can be combined to form a better embodiment. Considering the simplicity of the text, it will not be elaborated here.

[0130] Although some specific embodiments of the present application have been described in detail by way of examples, those skilled in the art should understand that the above examples are for illustrative purposes only and not for limiting the scope of the present application. Those skilled in the art should understand that the above embodiments can be modified without departing from the scope and spirit of the present application. The scope of the present application is defined by the appended claims.

Claims

1. A light projector, characterized in that: including a light source for emitting a laser beam; The light source comprises a light emitting panel (1), on which light source regions arranged in different ways are arranged, and which at least comprises a first light source region (11) and a second light source region (12); The first light source area (11) is configured to be capable of being used for projecting a speckle pattern, and the second light source area (12) is configured to be capable of being used for projecting a stripe pattern.

2. The light projector according to claim 1, characterized in that Light source areas with different arrangements on the light-emitting panel (1) can be illuminated independently in different areas.

3. The light projector according to claim 2, characterized in that The first light source area (11) is a stripe-shaped light-emitting area, which includes at least one stripe-shaped light-emitting module and can be used to obtain a stripe pattern; The second light source area (12) is a hole-shaped light-emitting area, which includes a plurality of light-emitting holes arranged in a set manner and can be used to obtain a speckle pattern.

4. The light projector according to claim 2, characterized in that The first light source region (11) and the second light source region (12) are both hole-shaped light-emitting regions; The first light source region (11) includes a first light-emitting hole array, and the second light source region (12) includes a second light-emitting hole array. The light-emitting holes in the first light-emitting hole array and the second light-emitting hole array have two different hole spacings, and the light-emitting holes in the first light-emitting hole array are arranged in a strip structure.

5. The light projector according to claim 4, characterized in that There is a first hole spacing between the light-emitting holes on the first light-emitting hole array, and there is a second hole spacing between the light-emitting holes on the second light-emitting hole array; The first hole spacing is smaller than the target hole spacing, so that the speckles obtained by diffraction of the light-emitting holes on the first light-emitting hole array overlap with each other, thereby obtaining a fringe pattern; The second hole spacing is greater than the target hole spacing, so that the speckles obtained by diffraction of the light-emitting holes on the second light-emitting hole array will not overlap, thereby obtaining a speckle pattern.

6. The light projector according to claim 4, characterized in that The relationship between the hole spacing AB between the light holes on the first light hole array and the distance A'B' between the spots in the corresponding speckle pattern is AB: A'B'=f:(vf); wherein f is the focal length of the light projector, and v is the projection distance of the light projector.

7. The light projector according to claim 2, characterized in that The light projector further comprises a control module for controlling the lighting status of different light source areas on the light emitting panel, so as to realize the switching between the speckle image mode and / or the stripe image mode.

8. The light projector according to claim 3 or 4, characterized in that: The arrangement of the light-emitting holes on the hole-shaped light-emitting area includes regular arrangement or random arrangement.

9. The light projector according to claim 1, characterized in that The light projector further comprises a diffractive optical element, and the diffractive optical element is arranged on the light emitting side of the light emitting panel (1); The pattern formed on the projection surface by the laser beam emitted by the light-emitting panel (1) after passing through the diffractive optical element is a regular splicing pattern or a staggered splicing pattern.

10. The light projector according to claim 1, characterized in that The first light source area (11) and the second light source area (12) are respectively provided to be at least one; The first light source area (11) and the second light source area (12) are arranged in a set manner on the surface of the light-emitting panel (1).

11. A three-dimensional reconstruction system, characterized in that: include: A light projector as claimed in any one of claims 1 to 10; and camera.

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