Structured light projector and three-dimensional image sensing device

Abstract

To provide a structured light projector.SOLUTION: The structured light projector includes: a first light source and a second light source which are configured to respectively emit first incoherent light and second incoherent light; an optical refractive element which is arranged over the first and second light sources for refracting the first incoherent light and the second incoherent light; and an optical shaper element which is arranged over the optical refractive element for shaping the first incoherent light to generate first structured light with plural first optical patterns and shaping the second incoherent light to generate second structured light with plural second optical patterns. The first structured light and the second structured light are overlapped onto a region of space.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to structured light projection, and in particular to a structured light projector and a three-dimensional image sensing device. [Background technology]

[0002] 3D stereoscopic image sensing technology is gradually being adopted for various applications, such as face recognition and obstacle detection. For recognition, different types of structured light projectors may be adopted for different applications. For example, a structured light projector can project a light spot pattern to calculate the surface contour of a person's face, and can project a light line pattern to calculate human motion. Meanwhile, the projection uniformity of a structured light projector is one of the key factors related to the sensing quality. Summary of the Invention [Problem to be solved by the invention]

[0003] SUMMARY OF THE PRESENT EMBODIMENT An object of the present invention is to provide a structured light projector and a 3D image sensing device that projects a light pattern with high uniformity so as to achieve better 3D sensing quality. [Means for solving the problem]

[0004] One aspect of the present invention is a structured light projector including a first light source and a second light source arranged to emit a first incoherent light and a second incoherent light, respectively; an optical refraction element arranged above the first light source and the second light source to refract the first incoherent light and the second incoherent light; and a light shaping element arranged above the optical refraction element to shape the first incoherent light to generate a first structured light having a plurality of first optical patterns, and to shape the second incoherent light to generate a second structured light having a plurality of second optical patterns, wherein the first structured light and the second structured light overlap in a spatial domain.

[0005] According to one or more embodiments of the invention, the distance between the first light source and the light refractive element is substantially the same as the distance between the second light source and the light refractive element.

[0006] According to one or more embodiments of the present invention, the first light source and the second light source are both vertical cavity surface emitting laser sources (VCSELs).

[0007] According to one or more embodiments of the present invention, the first optical pattern and the second optical pattern are both M×N light spot patterns, the (M-1)×N light spot patterns of the first optical pattern and the (M-1)×N light spot patterns of the second optical pattern overlap in the spatial region, and M and N are integers greater than 1.

[0008] According to one or more embodiments of the invention, the light shaping element is a two-dimensional fan out diffractive optical element (DOE).

[0009] According to one or more embodiments of the invention, the light shaping element is a microlens array.

[0010] According to one or more embodiments of the invention, the structured light projector further comprises a light patterning element disposed between the light refractive element and the light shaping element.

[0011] According to one or more embodiments of the invention, the optical patterning element is a diffractive line pattern generating element.

[0012] According to one or more embodiments of the present invention, the first optical pattern and the second optical pattern are both M×N light line patterns, the (M-1)×N light line patterns of the first optical pattern and the (M-1)×N light line patterns of the second optical pattern overlap in a spatial domain, and M and N are integers greater than 1.

[0013] According to one or more embodiments of the present invention, the light shaping element and the light patterning element are both one-dimensional fan-out diffractive optical elements.

[0014] According to one or more embodiments of the invention, the photorefractive element and the photopatterning element are an integrated one-dimensional fan-out diffractive optical element.

[0015] According to one or more embodiments of the invention, the structured light projector further comprises a light patterning element disposed above the light projection side of the light shaping element.

[0016] According to one or more embodiments of the invention, the light shaping element is a two-dimensional tiling diffractive optical element and the light patterning element is a diffractive line pattern generating element.

[0017] According to one or more embodiments of the present invention, the structured light projector further includes a third light source and a fourth light source arranged to emit a third incoherent light and a fourth incoherent light, respectively, the light refraction element is also arranged above the third light source and the fourth light source to refract the third incoherent light and the fourth incoherent light, the light shaping element is also arranged to shape the third incoherent light to generate a third structured light having a plurality of third optical patterns and to shape the fourth incoherent light to generate a fourth structured light having a plurality of fourth optical patterns, and the first to fourth structured lights overlap in the spatial domain.

[0018] According to one or more embodiments of the present invention, the first to fourth light sources are provided at the four corners of a virtual square, respectively.

[0019] According to one or more embodiments of the present invention, the first to fourth optical patterns overlap in two mutually perpendicular directions.

[0020] According to one or more embodiments of the present invention, the first optical pattern, the second optical pattern, the third optical pattern and the fourth optical pattern are all M×N light spot patterns, the (M-1)×(N-1) light spot patterns of the first optical pattern, the (M-1)×(N-1) light spot patterns of the second optical pattern, the (M-1)×(N-1) light spot patterns of the third optical pattern and the (M-1)×(N-1) light spot patterns of the fourth optical pattern overlap in a spatial domain, and M and N are integers greater than 1.

[0021] According to one or more embodiments of the present invention, the structured light projector further includes a light patterning element disposed between the light refraction element and the light shaping element, wherein the first optical pattern, the second optical pattern, the third optical pattern and the fourth optical pattern are all M×N light line patterns, the (M-1)×(N-1) light line patterns of the first optical pattern, the (M-1)×(N-1) light line patterns of the second optical pattern, the (M-1)×(N-1) light line patterns of the third optical pattern and the (M-1)×(N-1) light line patterns of the fourth optical pattern overlap in the spatial region, and M and N are integers greater than 1.

[0022] According to one or more embodiments of the invention, the light-refractive element is a collimator lens.

[0023] Another aspect of the invention is a three-dimensional image sensing device including a plurality of light sources arranged to emit a plurality of incoherent light beams each, a light refraction element arranged above the light sources to refract the incoherent light beams, a light shaping element arranged on the light refraction element to shape the incoherent light beams to generate a plurality of structured lights each having a plurality of optical patterns and overlapping in a spatial domain, an image sensor arranged to capture an image from the spatial domain, and a processor arranged to perform operations on the image to obtain three-dimensional data related to the spatial domain. [Brief description of the drawings]

[0024] BRIEF DESCRIPTION OF THE DRAWINGS For a more complete understanding of the embodiments and their advantages, reference is now made to the following detailed description taken in conjunction with the accompanying drawings, in which: FIG. [Figure 1] FIG. 1 is a schematic diagram of a structured light projector in one example. [Diagram 2] FIG. 1 is a schematic diagram of a structured light projector in accordance with one or more embodiments of the invention. [Figure 3A] 3 exemplarily illustrates structured light having a light spot pattern projected by the structured light projector in FIG. 2. [Figure 3B] 3B shows structured light having the light spot patterns in FIG. 3A, respectively. [Figure 3C] 3B shows structured light having the light spot patterns in FIG. 3A, respectively. [Figure 4] FIG. 1 is a schematic diagram of a structured light projector in accordance with one or more embodiments of the invention. [Diagram 5] FIG. 1 is a schematic diagram of a structured light projector in accordance with one or more embodiments of the invention. [Figure 6] FIG. 1 is a schematic diagram of a structured light projector in accordance with one or more embodiments of the invention. [Figure 7A] 7 exemplarily illustrates structured light having a light beam pattern projected by the structured light projector in FIG. 6. [Figure 7B]7B shows structured light having a beam pattern as in FIG. 7A. [Figure 7C] 7B shows structured light having a beam pattern as in FIG. 7A. [Figure 8] FIG. 1 is a schematic diagram of a structured light projector in accordance with one or more embodiments of the invention. [Figure 9] 1 illustrates an exemplary installation of a structured light projector in accordance with one or more embodiments of the present invention. [Figure 10] FIG. 1 is a schematic diagram of a structured light projector in accordance with one or more embodiments of the invention. [Figure 11A] 11 exemplarily illustrates structured light having a light spot pattern projected by the structured light projector in FIG. [Figure 11B] 11B shows structured light having the light spot pattern in FIG. 11A. [Figure 11C] 11B shows structured light having the light spot pattern in FIG. 11A. [Figure 11D] 11B shows structured light having the light spot pattern in FIG. 11A. [Figure 11E] 11B shows structured light having the light spot pattern in FIG. 11A. [Figure 12] FIG. 1 is a schematic diagram of a structured light projector in accordance with one or more embodiments of the invention. [Figure 13A] 13 exemplarily illustrates structured light having a light beam pattern projected by the structured light projector in FIG. 12. [Figure 13B] 13B shows structured light having a line pattern in FIG. 13A. [Figure 13C] 13B shows structured light having a line pattern in FIG. 13A. [Figure 13D] 13B shows structured light having a line pattern in FIG. 13A. [Figure 13E] 13B shows structured light having a line pattern in FIG. 13A. [Figure 14A]13A and 13B are illustrative diagrams showing structured light having a light line pattern projected by the structured light projector in the comparative example and the structured light projector in FIG. 12, respectively. [Figure 14B] 13A and 13B are illustrative diagrams showing structured light having a light line pattern projected by the structured light projector in the comparative example and the structured light projector in FIG. 12, respectively. [Figure 15A] 11A and 11B are illustrative diagrams showing structured light having light spot patterns projected by the structured light projector in the comparative example and in FIG. 10, respectively. [Figure 15B] 11A and 11B are illustrative diagrams showing structured light having light spot patterns projected by the structured light projector in the comparative example and in FIG. 10, respectively. [Figure 16] 1 is a schematic diagram of a three-dimensional image sensing device in one or more embodiments of the present invention; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] In the following, the embodiments of the present disclosure will be considered in detail. However, it will be understood that the embodiments provide many applicable concepts, and that these concepts can be embodied in a variety of specific contexts. The embodiments discussed and disclosed are for illustrative purposes only and are not intended to limit the scope of the present disclosure.

[0026] It will be understood that although terms such as "first," "second," "third," "fourth," etc. may be used herein to describe various elements and / or components, these terms are not intended to be limiting of these elements and / or components. These terms are used only to distinguish one element and / or component from another.

[0027] The terms used in this specification are only for the purpose of describing particular embodiments and are not intended to limit the scope of the claims. Unless otherwise limited, the singular terms "a" or "the" can also be used to refer to the plural. Spatially relative terms are also used to describe different orientations in use or operation of the device and are not limited to the orientation shown in the drawings. The device may be oriented in other configurations (rotated 90 degrees or at other orientations) and the spatially relative descriptions used herein may be understood in the same manner.

[0028] For simplicity and clarity of description, the specification may repeat element reference numbers and / or letters in the various embodiments, but this does not imply a causal relationship between the various embodiments and / or configurations discussed.

[0029] Fig. 1 is a schematic diagram of an example structured light projector 100. As shown in Fig. 1, the structured light projector 100 includes a light source 110, a light refraction element 120, and a light shaping element 130. The light source 110 is arranged to emit light. The light refraction element 120 is disposed above the light source 110 to refract the light emitted by the light source 110 to the light shaping element 130. The light shaping element 130 is disposed above the light refraction element 120 to transform the refracted light into a projected light pattern and project the projected light pattern into a spatial region S.

[0030] FIG. 2 is a schematic diagram of a structured light projector 200 in one or more embodiments of the present invention. As shown in FIG. 2, the structured light projector 200 includes light sources 210A, 210B, a photorefractive element 220, and a light shaping element 230. Each light source 210A, 210B is arranged to emit incoherent light, and may be a laser source such as a vertical cavity surface emitting laser (VCSEL), a distributed feedback (DFB) semiconductor laser source, or other suitable light source. The photorefractive element 220 is disposed above the light sources 210A, 210B to refract the incoherent light emitted by the light sources 210A, 210B to the light shaping element 230. The photorefractive element 220 may be, but is not limited to, a collimator lens, a convex lens, a concave lens, a liquid crystal lens, or a Fresnel lens. When the light sources 210A and 210B emit the same incoherent light, the distance between the light source 210A and the light refraction element 220 may be substantially the same as the distance between the light source 210B and the light refraction element 220. The light shaping element 230 is disposed above the light refraction element 220 to shape the incoherent light refracted by the light refraction element 220 to generate the structured light SLA, SLB. In the case of the structured light projector 200, each structured light SLA, SLB may be generated to have a plurality of optical patterns, such as light spot patterns or the like. The light shaping element 230 may be a two-dimensional fan-out diffractive optical element (DOE), a microlens array, a Fresnel lens array, a holographic optical element (HOE), or other optical element that shapes the incoherent light into a structured light having an optical pattern. The structured light SLA and SLB are projected into a spatial region S and overlap in the spatial region S. The intensity distribution of the optical patterns of the structured light SLA and SLB can be adjusted by the profile of the light shaping element 230.

[0031] FIG. 3A exemplarily illustrates the structured light SLA having the light spot pattern DPA and the structured light SLB having the light spot pattern DPB projected by the structured light projector 200 in FIG. 2. As shown in FIG. 3A, in the overlapping region of the structured light SLA and SLB, the light spot pattern DPA overlaps with the light spot pattern DPB, respectively. The overlapping region is also called the high uniformity projection region, and the light spot patterns DPA and DPB overlap in a one-to-one manner in the high uniformity projection region. FIG. 3B and FIG. 3C also respectively illustrate the structured light SLA having the light spot pattern DPA and the structured light SLB having the light spot pattern DPB in FIG. 3A. As shown in FIG. 3A-3C, the light spot pattern DPA in the top row does not overlap with any light spot pattern DPB, and the light spot pattern DPB in the bottom row does not overlap with any light spot pattern DPA. In the exemplary embodiment shown in FIG. 3A-3C, the structured light SLA and SLB overlap in the vertical direction. In other embodiments, the structured light SLA, SLB may be overlapped horizontally or diagonally by appropriately adjusting the positions of the light sources 210A, 210B.

[0032] In some embodiments, the light spot patterns of the structured light SLA and SLB are both M×N light spot patterns. In particular, when the structured light SLA and SLB overlap in the vertical direction, in some embodiments, the (M-1)×N light spot pattern of the structured light SLA and the (M-1)×N light spot pattern of the structured light SLB overlap in a spatial region S, where M and N are integers greater than 1; or in another embodiment, the (Mi)×N light spot pattern of the structured light SLA and the (Mi)×N light spot pattern of the structured light SLB overlap in a spatial region S, where M and N are integers greater than 1, and i is an integer greater than 1 and less than M. When the structured light SLA and SLB overlap horizontally, in some embodiments, the M×(N-1) light spot patterns of the structured light SLA and the M×(N-1) light spot patterns of the structured light SLB overlap in a spatial region S, where M and N are integers greater than 1, or in other embodiments, the M×(Nj) light spot patterns of the structured light SLA and the M×(Nj) light spot patterns of the structured light SLB overlap in a spatial region S, where M and N are integers greater than 1, and j is an integer greater than 1 and less than N.

[0033] The high uniformity of the projection of the overlapping regions of the light spot patterns shown in Figures 3A-3C may be achieved by other structured light projectors derived from the structured light projector 200 in Figure 2. Figure 4 is a schematic diagram of a structured light projector 400 in one or more embodiments of the present invention. As shown in Figure 4, the structured light projector 400 includes light sources 410A, 410B, a photorefractive element 420, a light patterning element 430, and a light shaping element 440. Each light source 410A, 410B is arranged to emit incoherent light and may be a laser source such as a vertical cavity surface emitting laser source, a distributed feedback semiconductor laser source, or other suitable light source. The photorefractive element 420 is disposed above the light sources 410A, 410B to refract the incoherent light from the light sources 410A, 410B to the light patterning element 430. The photorefractive element 420 may be, but is not limited to, a collimator lens, a convex lens, a concave lens, a liquid crystal lens, or a Fresnel lens. When the light sources 410A and 410B emit the same incoherent light, the distance between the light source 410A and the photorefractive element 420 may be substantially the same as the distance between the light source 410B and the photorefractive element 420. The light patterning element 430 is disposed between the photorefractive element 420 and the light shaping element 440, so as to pattern the incoherent light refracted by the photorefractive element 420 into a diffracted light spot. The light patterning element 430 may be a diffractive linear pattern generating element, such as a one-dimensional fan-out type diffractive optical element or other optical elements suitable for generating diffracted light spots in one direction. The light shaping element 440 is disposed above the light patterning element 430 to shape the diffracted light pattern to generate the structured light SLA, SLB, all having light spot patterns, and project the structured light SLA, SLB into the spatial region S. The light shaping element 440 may be a diffractive line pattern generating element, such as a one-dimensional fan-out diffractive optical element or other optical element suitable for generating diffracted light spots in another direction perpendicular to the diffraction direction of the light patterning element 430. The arrangement of the structured light projector 400 also provides zero-order cancellation.

[0034] Another structured light projector derived from structured light projector 200 to achieve the contents shown in Figures 3A-3C is shown in Figure 5. Figure 5 is a schematic diagram of a structured light projector 500 in one or more embodiments of the present invention. As shown in Figure 5, the structured light projector 500 includes light sources 510A, 510B, an integrated diffractive optical element 520, and a light shaping element 530. Each light source 510A, 510B is arranged to emit incoherent light and may be a laser source such as a vertical cavity surface emitting laser source, a distributed feedback semiconductor laser source, or other suitable light source. The integrated diffractive optical element 520 is disposed above the light sources 510A, 510B to refract the incoherent light from the light sources 510A, 510B to the light shaping element 530 and pattern the incoherent light into a diffracted light spot. The integrated diffractive optical element 520 may be an integrated one-dimensional fan-out diffractive optical element that integrates an optical lens and a one-dimensional fan-out diffractive optical element to generate diffracted light spots in one direction. When the same incoherent light is emitted by the light sources 510A and 510B respectively, the distance between the light source 510A and the integrated diffractive optical element 520 may be substantially the same as the distance between the light source 510B and the integrated diffractive optical element 520. The light shaping element 530 is disposed above the integrated diffractive optical element 520 to shape the diffracted light spots to generate structured light SLA, SLB that all have light spot patterns, and project the structured light SLA, SLB into the spatial region S. The light shaping element 530 may be a diffractive line pattern generating element, such as a one-dimensional fan-out diffractive optical element or other optical elements suitable for generating diffracted light spots in another direction perpendicular to the diffraction direction of the integrated diffractive optical element 520.

[0035] 6 is a schematic diagram of a structured light projector 600 in one or more embodiments of the present invention. As shown in FIG. 6, the structured light projector 600 includes light sources 610A, 610B, a photorefractive element 620, a light patterning element 630, and a light shaping element 640. Each light source 610A, 610B is arranged to emit incoherent light, and may be a laser source, such as a vertical cavity surface emitting laser source, a distributed feedback semiconductor laser source, or other suitable light source. The photorefractive element 620 is disposed above the light sources 610A, 610B to refract the incoherent light from the light sources 610A, 610B to the light patterning element 630. The photorefractive element 620 may be, but is not limited to, a collimator lens, a convex lens, a concave lens, a liquid crystal lens, or a Fresnel lens. When the light sources 610A and 610B emit the same incoherent light, respectively, the distance between the light source 610A and the light refraction element 620 may be substantially the same as the distance between the light source 610B and the light refraction element 620. The light patterning element 630 is provided between the light refraction element 620 and the light shaping element 640 to pattern the incoherent light refracted by the light refraction element 620 into a diffracted beam. The light patterning element 630 may be a diffractive line pattern generating element, such as a diffractive optical element that generates a line shape or other optical element suitable for generating a diffractive beam shape. The light shaping element 640 is provided on the light patterning element 630 to shape the diffracted beam shape to generate the structured light SLA, SLB. In the arrangement of the structured light projector 600, each structured light SLA, SLB may be generated to have a plurality of optical patterns, such as a beam pattern or the like. The light shaping element 640 may be a two-dimensional fan-out diffractive optical element or other optical element suitable for shaping incoherent light into structured light having an optical pattern. The structured light SLA, SLB is projected into the spatial region S and overlaps in the spatial region S.

[0036] FIG. 7A exemplarily illustrates the structured light SLA having the light beam pattern LPA and the structured light SLB having the light beam pattern LPB projected by the structured light projector 600 in FIG. 6. As shown in FIG. 7A, in the overlapping region of the structured light SLA and SLB, the light beam pattern LPA overlaps with the light beam pattern LPB, respectively. The overlapping region is also called a high uniformity projection region, and the light beam patterns LPA and LPB overlap in a one-to-one manner in the high uniformity projection region. FIGS. 7B and 7C also illustrate the structured light SLA and SLB having the light beam patterns LPA and LPB in FIG. 7A, respectively. As shown in FIGS. 7A to 7C, the light beam pattern LPA in the top row does not overlap with any light beam pattern LPB, and the light beam pattern LPB in the bottom row does not overlap with any light beam pattern LPA. In the exemplary embodiment shown in FIGS. 7A to 7C, the structured light SLA and SLB overlap in the vertical direction. In other embodiments, the structured light SLA, SLB may be overlapped horizontally or diagonally by appropriately adjusting the relative positions of the light sources 610A, 610B.

[0037] In some embodiments, the number of light beam patterns of the structured light SLA and SLB is M × N. In particular, when the structured light SLA and SLB overlap in the vertical direction, in some embodiments, the (M-1) × N light beam patterns of the structured light SLA and the (M-1) × N light beam patterns of the structured light SLB overlap in the spatial region S, where M and N are integers greater than 1, or in another embodiment, the (Mi) × N light beam patterns of the structured light SLA and the (Mi) × N light beam patterns of the structured light SLB overlap in the spatial region S, where M and N are integers greater than 1, and i is an integer greater than 1 and less than M. When the structured light SLA and SLB overlap horizontally, in some embodiments, the M×(N-1) light beam patterns of the structured light SLA and the M×(N-1) light beam patterns of the structured light SLB overlap in a spatial domain S, where M and N are integers greater than 1, or in another embodiment, the M×(Nj) light beam patterns of the structured light SLA and the M×(Nj) light beam patterns of the structured light SLB overlap in a spatial domain S, where M and N are integers greater than 1, and j is an integer greater than 1 and less than N.

[0038] The high uniformity of the projection of the overlapping region of the light line patterns shown in Figures 7A-7C may be achieved by other structured light projectors derived from the structured light projector 600 in Figure 6. Figure 8 is a schematic diagram of a structured light projector 800 in one or more embodiments of the present invention. As shown in Figure 8, the structured light projector 800 includes light sources 810A, 810B, a photorefractive element 820, a light shaping element 830, and a light patterning element 840. Each of the light sources 810A, 810B is arranged to emit incoherent light, and may be a laser source such as a vertical cavity surface emitting laser source, a distributed feedback semiconductor laser source, or other suitable light source. The photorefractive element 820 is disposed above the light sources 810A, 810B to refract the incoherent light from the light sources 810A, 810B to the light shaping element 830. The light refraction element 820 may be, but is not limited to, a collimator lens, a convex lens, a concave lens, a liquid crystal lens, or a Fresnel lens. When the same incoherent light is emitted by the light sources 810A and 810B, respectively, the distance between the light source 810A and the light refraction element 820 may be substantially the same as the distance between the light source 810B and the light refraction element 820. The light shaping element 830 is provided between the light refraction element 820 and the light patterning element 840, so as to shape the diffracted light beam shape refracted by the light refraction element 820 to generate structured light SLA, SLB, all of which have light spot patterns, and project the structured light SLA, SLB into the spatial region S. The light shaping element 830 may be a two-dimensional tiling diffractive optical element, a microlens array, a Fresnel lens array, a holographic optical element, or other optical elements suitable for shaping incoherent light into structured light having light spot patterns. The light patterning element 840 is disposed above the light projection side of the light shaping element 830 so as to pattern and convert the light spot pattern of the structured light SLA, SLB into a light line pattern. The light patterning element 840 may be a diffractive line pattern generating element, such as a one-dimensional fan-out diffractive optical element or other optical element suitable for generating diffracted light spots in one direction.

[0039] FIG. 9 illustrates an exemplary installation of a structured light projector 900 in accordance with one or more embodiments of the present invention. As shown in FIG. 9, the structured light projector 900 includes light sources 910A, 910B, a light refractive element 920, and a light shaping element 930. The light sources 910A, 910B, the light refractive element 920, and the light shaping element 930 are similar to the light sources 210A, 210B, the light refractive element 220, and the light shaping element 230 of the structured light projector 200 in FIG. 2, respectively. In particular, the light refractive element 920 is a convex lens, and the light shaping element 930 is a microlens array, and includes a plurality of microstructures 930M arranged in the array. In FIG. 9, the angle α is expressed as tan -1 (d / f eff ), where d is the pitch of the light sources 910A, 910B, and f eff is the effective focal length of the optical refractive element 920. eff is substantially the same as the distance between the light source 910A / 910B and the light refractive element 920. The included angle θ between the center of the structured light SLA and the center of the structured light SLB with respect to the center of the light shaping element 930 is sin -1 (d / f eff ) When the included angle θ is equal to the angle α, the light spot patterns of the structured light SLA and SLB overlap. The installation positions of the light sources 910A and 910B may be determined according to the above description. The installation positions of the light sources in each embodiment may be determined similarly.

[0040] FIG. 10 is a schematic diagram of a structured light projector 1000 in one or more embodiments of the present invention. As shown in FIG. 10, the structured light projector 1000 includes light sources 1010A-1010D, a photorefractive element 1020, and a light shaping element 1030. The light sources 1010A-1010D may be disposed at the four corners of an imaginary square. Each of the light sources 1010A-1010D is arranged to emit incoherent light, and may be a laser source such as a vertical cavity surface emitting laser source, a distributed feedback semiconductor laser source, or other suitable light source. The photorefractive element 1020 is disposed above the light sources 1010A-1010D to refract the incoherent light from the light sources 1010A-1010D to the light shaping element 1030. The light refraction element 1020 may be, but is not limited to, a collimator lens, a convex lens, a concave lens, a liquid crystal lens, or a Fresnel lens. When the same incoherent light is emitted by each of the light sources 1010A to 1010D, the distance between the light source 1010A and the light refraction element 1020 may be substantially the same as the distance between the light source 1010B and the light refraction element 1020, may be substantially the same as the distance between the light source 1010C and the light refraction element 1020, and may be substantially the same as the distance between the light source 1010D and the light refraction element 1020. The light shaping element 1030 is provided above the light refraction element 1020 to shape the incoherent light refracted by the light refraction element 1020 to generate the structured light SLA, SLB. In the arrangement of the structured light projector 1000, each structured light SLA, SLB may be generated to have a plurality of optical patterns, such as a light spot pattern or the like. The light shaping element 1030 may be a two-dimensional fan-out diffractive optical element, a microlens array, or other optical elements suitable for shaping incoherent light into structured light having an optical pattern. The structured light SLA, SLB is projected into the spatial region S and overlaps in the spatial region S.

[0041] Fig. 11A exemplarily illustrates structured light SLA having light spot pattern DPA, structured light SLB having light spot pattern DPB, structured light SLC having light spot pattern DPC, and structured light SLD having light spot pattern DPD projected by structured light projector 1000 in Fig. 10. As shown in Fig. 11A, in the overlapping region of structured light SLA to SLD, the light spot pattern DPA overlaps with the light spot pattern DPB, the light spot pattern DPC, and the light spot pattern DPD. The light spot pattern DPA overlaps with the light spot pattern DPB in the overlapping region of the structured light SLA and SLB, the light spot pattern DPA overlaps with the light spot pattern DPC in the overlapping region of the structured light SLA and SLC, the light spot pattern DPB overlaps with the light spot pattern DPD in the overlapping region of the structured light SLB and SLD, and the light spot pattern DPC overlaps with the light spot pattern DPD in the overlapping region of the structured light SLC and SLD. The overlapping region of the structured light SLA to SLD is also called a high uniformity projection region, and the light spot patterns DPA to DPD overlap in a one-to-one manner. Figures 11B to 11E also show the structured light SLA to SLD having the light spot patterns DPA to DPD in Figure 11A, respectively. As shown in Figures 11A to 11E, the upper left light spot pattern DPA does not overlap with any of the light spot patterns DPB to DPD, the upper right light spot pattern DPB does not overlap with any of the light spot patterns DPA, DPC, and DPD, the lower left light spot pattern DPC does not overlap with any of the light spot patterns DPA, DPB, and DPD, and the lower right light spot pattern DPD does not overlap with any of the light spot patterns DPA, DPB, and DPC. In the illustrative examples shown in Figures 11A to 11E, they overlap in two mutually perpendicular directions (e.g., vertical and horizontal directions). In other embodiments, the structured light SLA to SLD may overlap in two mutually perpendicular diagonal directions by appropriately adjusting the relative positions of the light sources 1010A to 1010D.

[0042] In some embodiments, the light spot pattern of the structured light SLA, the light spot pattern of the structured light SLB, the light spot pattern of the structured light SLC and the light spot pattern of the structured light SLD are all M×N light spot patterns. In particular, when the structured light SLA to SLD overlap in the vertical and horizontal directions, in some embodiments, the (M-1)×(N-1) light spot patterns of the structured light SLA, the (M-1)×(N-1) light spot patterns of the structured light SLB, the (M-1)×(N-1) light spot patterns of the structured light SLC and the (M-1)×(N-1) light spot patterns of the structured light SLD overlap in the spatial region S, and M and N are integers greater than 1, or In another embodiment, the (Mi)×(Nj) light spot patterns of the structured light SLA, the (Mi)×(Nj) light spot patterns of the structured light SLB, the (Mi)×(Nj) light spot patterns of the structured light SLC and the (Mi)×(Nj) light spot patterns of the structured light SLD overlap in a spatial region S, where M and N are integers greater than 1, i is an integer greater than 1 and less than M, and j is an integer greater than 1 and less than N.

[0043] FIG. 12 is a schematic diagram of a structured light projector 1200 in one or more embodiments of the present invention. As shown in FIG. 12, the structured light projector 1200 includes light sources 1210A-1210D, a photorefractive element 1220, a light patterning element 1230, and a light shaping element 1240. The light sources 1210A-1210D may be disposed at the four corners of an imaginary square. Each of the light sources 1210A-1210D is arranged to emit incoherent light, and may be a laser source such as a vertical cavity surface emitting laser source, a distributed feedback semiconductor laser source, or other suitable light source. The photorefractive element 1220 is disposed above the light sources 1210A-1210D to refract the incoherent light from the light sources 1210A-1210D to the light patterning element 1230. The light refraction element 1220 may be, but is not limited to, a collimator lens, a convex lens, a concave lens, a liquid crystal lens, or a Fresnel lens. When the same incoherent light is emitted by each of the light sources 1210A to 1210D, the distance between the light source 1210A and the light refraction element 1220 may be substantially the same as the distance between the light source 1210B and the light refraction element 1220, may be substantially the same as the distance between the light source 1210C and the light refraction element 1220, and may be substantially the same as the distance between the light source 1210D and the light refraction element 1220. The light patterning element 1230 is provided between the light refraction element 1220 and the light shaping element 1240 so as to pattern the incoherent light refracted by the light refraction element 1220 into a diffracted light beam. The light patterning element 1230 may be a diffractive light pattern generating element, such as a diffractive optical element generating a line shape or other optical element suitable for generating a diffracted light line shape. The light shaping element 1240 is provided above the light patterning element 1230 to shape the diffracted light line shape to generate the structured light SLA-SLD. In the configuration of the structured light projector 1200, each structured light SLA-SLD may be generated to have multiple optical patterns, such as light line patterns or the like. The light shaping element 1240 may be a two-dimensional fan-out type diffractive optical element or other optical element suitable for shaping incoherent light into structured light having an optical pattern. The structured light SLA-SLD is projected into a spatial region S and overlaps in the spatial region S.

[0044] Fig. 13A exemplarily illustrates structured light SLA having a light beam pattern LPA, structured light SLB having a light beam pattern LPB, structured light SLC having a light beam pattern LPC, and structured light SLD having a light beam pattern LPD, projected by the structured light projector 1200 in Fig. 12. As shown in Fig. 13A, in the overlapping region of the structured light SLA to SLD, the light beam patterns LPA overlap with the light beam patterns LPB, LPC, and LPD. The light beam pattern LPA overlaps with the light beam pattern LPB in the overlapping region of the structured light SLA and SLB, and overlaps with the light beam pattern LPC in the overlapping region of the structured light SLA and SLC, the light beam pattern LPB overlaps with the light beam pattern LPD in the overlapping region of the structured light SLB and SLD, and the light beam pattern LPC overlaps with the light beam pattern LPD in the overlapping region of the structured light SLC and SLD. The overlapping region of the structured light SLA to SLD is also called a high uniformity projection region, and the light beam patterns LPA to LPD overlap in a one-to-one manner in the high uniformity projection region. Figures 13B to 13E also show the structured light SLA to SLD having the light beam patterns LPA to LPD in Figure 13A, respectively. As shown in Figures 13A to 13E, the upper left light beam pattern LPA does not overlap with any of the light beam patterns LPB to LPD, the upper right light beam pattern LPB does not overlap with any of the light beam patterns LPA, LPC, and LPD, the lower left light beam pattern LPC does not overlap with any of the light beam patterns LPA, LPB, and LPD, and the lower right light beam pattern LPD does not overlap with any of the light beam patterns LPA to LPC. In the illustrative examples shown in Figures 13A to 13E, the structured light SLA to SLD overlap in two mutually perpendicular directions (e.g., vertical and horizontal directions). In other embodiments, the structured light SLA to SLD may overlap in two mutually perpendicular diagonal directions by appropriately adjusting the relative positions of the light sources 1210A to 1210D.

[0045] In some embodiments, the light beam patterns of the structured light SLA, the light beam patterns of the structured light SLB, the light beam patterns of the structured light SLC and the light beam patterns of the structured light SLD are all M×N light beam patterns. In particular, when the structured light SLA to SLD overlap in the vertical and horizontal directions, in some embodiments, the (M-1)×(N-1) light beam patterns of the structured light SLA, the (M-1)×(N-1) light beam patterns of the structured light SLB, the (M-1)×(N-1) light beam patterns of the structured light SLC and the (M-1)×(N-1) light beam patterns of the structured light SLD overlap in the spatial region S, and M and N are integers greater than 1, or In another embodiment, the (Mi)×(Nj) light beam patterns of the structured light SLA, the (Mi)×(Nj) light beam patterns of the structured light SLB, the (Mi)×(Nj) light beam patterns of the structured light SLC and the (Mi)×(Nj) light beam patterns of the structured light SLD overlap in a spatial domain S, where M and N are integers greater than 1, i is an integer greater than 1 and less than M, and j is an integer greater than 1 and less than N.

[0046] 14A and 14B exemplarily show structured light having a light beam pattern projected by the comparative example and the structured light projector 1200 in FIG. 12, respectively. The comparative example is similar to the structured light projector 100 in FIG. 1, and the light beam patterns projected thereby are not all overlapped. As can be seen from FIGS. 14A and 14B, the uniformity of the light beam pattern projected by the structured light projector 1200 is obviously higher than the uniformity of the light beam pattern projected by the comparative example. Also, FIGS. 15A and 15B exemplarily show structured light having a light spot pattern projected by the comparative example and the structured light projector 1000 in FIG. 10, respectively. The comparative example is similar to the structured light projector 100 in FIG. 1, and the light beam patterns projected thereby are not all overlapped. As can be seen from FIGS. 15A and 15B, the uniformity of the light spot pattern projected by structured light projector 1000 is obviously higher than the uniformity of the light spot pattern projected by the comparative example.

[0047] 16 is a schematic diagram of a three-dimensional image sensing device 1600 in one or more embodiments of the present invention. As shown in FIG. 16, the three-dimensional image sensing device 1600 includes a light source 1610, a light refractive element 1620, a light shaping element 1630, an image sensor 1604, and a processor 1606. The light source 1610, the light refractive element 1620, and the light shaping element 1630 may be similar to the light source 210A, 210B, the light refractive element 220, and the light shaping element 230 of the structured light projector 200 in FIG. 2, respectively, and may be included in the structured light projector 1602. In other words, the structured light projector 1602 may be similar to the structured light projector 200 in FIG. 2. In each embodiment, the structured light projector 1602 may be implemented as the structured light projector 400, 500, 600, 800, 1000, 1200, or other similar structured light projectors. The structured light projector 1602 is arranged to project overlapping structured light at the spatial region S. The image sensor 1604 is arranged to capture an image of a corresponding optical pattern from the spatial region. The image sensor 1604 may be a structured light sensor, a time of flight (ToF) ranging sensor, or a combination of the above, and may include a charge-coupled device (CCD) sensor, a complementary metal-oxide semiconductor (CMOS), or the like. The processor 1606 is arranged to perform operations on the image captured by the image sensor to obtain three-dimensional data related to the spatial region S.

[0048] The present disclosure has been disclosed as above by the embodiments, but the embodiments do not limit the present disclosure, and those skilled in the art can make some changes or modifications without departing from the spirit and scope of the present disclosure. Therefore, the scope of protection of the present disclosure is based on the contents specified in the following claims. [Explanation of symbols]

[0049] 100, 200, 400, 500, 600, 800, 900, 1000, 1200, 1602 Structured Light Projector 110, 210A, 210B, 410A, 410B, 510A, 510B, 610A, 610B, 810A, 810B, 910A, 910B, 1010A~1010D, 1210A~1210D, 1610 Light source 120, 220, 420, 620, 820, 920, 1020, 1220, 1620 Photorefractive element 130, 230, 440, 530, 640, 830, 930, 1030, 1240, 1630 Light shaping element 430, 630, 840, 1230 Photopatterning element 520 Integrated Diffractive Optical Element 930M Microstructure 1600 3D image sensing device 1604 Image Sensor 1606 processor DPA, DPB, DPC, DPD Light spot pattern LPA, LPB, LPC, LPD Light Line Pattern α angle θ included angle d Pitch S spatial domain SLA, SLB, SLC, SLD Structured Light

Claims

1. a first light source and a second light source configured to emit a first incoherent light and a second incoherent light, respectively; an optical refraction element disposed above the first light source and the second light source so as to refract the first incoherent light and the second incoherent light; a light shaping element disposed above the light refraction element to shape the first incoherent light to generate a first structured light having a plurality of first optical patterns and to shape the second incoherent light to generate a second structured light having a plurality of second optical patterns, the first structured light and the second structured light overlapping in a spatial region; Including, the first optical pattern comprises a first overlapping optical pattern and at least one first non-overlapping optical pattern, the second optical pattern comprises a second overlapping optical pattern and at least one second non-overlapping optical pattern, the first overlapping optical pattern overlaps with the second overlapping optical pattern within an overlap region of the first structured light and the second structured light, the at least one first non-overlapping optical pattern is located within a first non-overlapping region adjacent to the overlap region, the at least one second non-overlapping optical pattern is located within a second non-overlapping region adjacent to the overlap region, the first non-overlapping region is opposite the second non-overlapping region; A structured light projector, wherein the first overlapping optical pattern and the second overlapping optical pattern completely overlap within the overlap region.

2. 2. The structured light projector of claim 1, wherein a distance between the first light source and the light refractive element is substantially the same as a distance between the second light source and the light refractive element.

3. 2. The structured light projector of claim 1, wherein the first optical pattern and the second optical pattern are both M×N light spot patterns, the (M−1)×N light spot pattern of the first optical pattern and the (M−1)×N light spot pattern of the second optical pattern overlap in the spatial region, and M and N are integers greater than 1.

4. 2. The structured light projector of claim 1, wherein the light shaping element is a two-dimensional fan out diffractive optical element (DOE) or a microlens array.

5. 10. The structured light projector of claim 1 further comprising a light patterning element disposed between the light refractive element and the light shaping element.

6. 6. The structured light projector of claim 5, wherein the optical patterning element is a diffractive linear pattern generating element, the first optical pattern and the second optical pattern are both M×N light linear patterns, the (M-1)×N light linear patterns of the first optical pattern and the (M-1)×N light linear patterns of the second optical pattern overlap in the spatial region within the overlap region, 1×N light linear patterns of the first optical pattern are located in the first non-overlapping region, and 1×N light linear patterns of the second optical pattern are located in the second non-overlapping region, and M and N are integers greater than 1.

7. 6. The structured light projector of claim 5, wherein the light shaping element and the light patterning element are both one-dimensional fan-out diffractive optical elements.

8. 8. The structured light projector of claim 7, wherein the photorefractive element and the photopatterning element are integrated one-dimensional fan-out diffractive optical elements.

9. 10. The structured light projector of claim 1 further comprising a light patterning element disposed above the light projection side of the light shaping element.

10. 10. The structured light projector of claim 9, wherein the light shaping element is a two-dimensional tiling diffractive optical element and the light patterning element is a diffractive line pattern generating element.

11. a third light source configured to emit a third incoherent light; a fourth light source configured to emit a fourth incoherent light; Further comprising:

2. The structured light projector of claim 1, wherein the optical refraction element is also provided above the third light source and the fourth light source to refract the third incoherent light and the fourth incoherent light, the light shaping element is also provided to shape the third incoherent light to generate a third structured light having a plurality of third optical patterns, and to shape the fourth incoherent light to generate a fourth structured light having a plurality of fourth optical patterns, and the first to fourth structured lights overlap in the spatial region within the overlap region.

12. 12. The structured light projector of claim 11, wherein the first light source, the second light source, the third light source and the fourth light source are respectively arranged at four corners of an imaginary square, and the first optical pattern, the second optical pattern, the third optical pattern and the fourth optical pattern overlap in two mutually perpendicular directions.

13. 12. The structured light projector of claim 11, wherein the first optical pattern, the second optical pattern, the third optical pattern and the fourth optical pattern are all M×N light spot patterns, the (M−1)×(N−1) light spot patterns of the first optical pattern, the (M−1)×(N−1) light spot patterns of the second optical pattern, the (M−1)×(N−1) light spot patterns of the third optical pattern and the (M−1)×(N−1) light spot patterns of the fourth optical pattern overlap in the spatial region, and M and N are integers greater than 1.

14. a light patterning element disposed between the light refractive element and the light shaping element; The first optical pattern, the second optical pattern, the third optical pattern and the fourth optical pattern are all M×N light beam patterns, and the (M−1)×(N−1) light beam patterns of the first optical pattern, the (M−1)×(N−1) light beam patterns of the second optical pattern, the (M−1)×(N−1) light beam patterns of the third optical pattern and the (M−1)×(N−1) light beam patterns of the fourth optical pattern overlap in the spatial region within the overlap region, and the first 12. The structured light projector of claim 11, wherein one light beam pattern of the optical patterns is located within the first non-overlapping region, one light beam pattern of the second optical pattern is located within the second non-overlapping region, one light beam pattern of the third optical pattern is located within the third non-overlapping region, and one light beam pattern of the fourth optical pattern is located within the fourth non-overlapping region, the third non-overlapping region being on an opposite side of the fourth non-overlapping region, and M and N are integers greater than 1.

15. a plurality of light sources each configured to emit a plurality of incoherent light beams; a light refracting element disposed above the light source so as to refract the incoherent light; a light shaping element disposed on the light refractive element to shape the incoherent light to generate a plurality of structured lights each having a plurality of optical patterns and overlapping in a spatial region; an image sensor configured to capture an image from the spatial region; a processor configured to perform operations on the image to obtain three-dimensional data related to the spatial region; Including, the optical pattern of one of the structured lights comprises a first overlapping optical pattern and at least one first non-overlapping optical pattern, and the optical pattern of the other of the structured lights comprises a second overlapping optical pattern and at least one second non-overlapping optical pattern, the first overlapping optical pattern overlapping with the second overlapping optical pattern within an overlap region of the structured light, the at least one first non-overlapping optical pattern being located within a first non-overlapping region adjacent to the overlap region, the at least one second non-overlapping optical pattern being located within a second non-overlapping region adjacent to the overlap region, the first non-overlapping region being opposite the second non-overlapping region; A three-dimensional image sensing device, wherein the first overlapping optical pattern and the second overlapping optical pattern completely overlap within the overlap region.

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