CN108490628B - Structured light projector, depth camera and electronic device - Google Patents
Structured light projector, depth camera and electronic device Download PDFInfo
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- CN108490628B CN108490628B CN201810200423.6A CN201810200423A CN108490628B CN 108490628 B CN108490628 B CN 108490628B CN 201810200423 A CN201810200423 A CN 201810200423A CN 108490628 B CN108490628 B CN 108490628B
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- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
- G02B27/42—Diffraction optics, i.e. systems including a diffractive element being designed for providing a diffractive effect
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- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
- G02B27/42—Diffraction optics, i.e. systems including a diffractive element being designed for providing a diffractive effect
- G02B27/4205—Diffraction optics, i.e. systems including a diffractive element being designed for providing a diffractive effect having a diffractive optical element [DOE] contributing to image formation, e.g. whereby modulation transfer function MTF or optical aberrations are relevant
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B11/00—Measuring arrangements characterised by the use of optical techniques
- G01B11/24—Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures
- G01B11/25—Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures by projecting a pattern, e.g. one or more lines, moiré fringes on the object
- G01B11/2513—Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures by projecting a pattern, e.g. one or more lines, moiré fringes on the object with several lines being projected in more than one direction, e.g. grids, patterns
Abstract
The invention discloses a structured light projector, a depth camera and an electronic device. The structured light projector includes a light source, a collimating element, and a diffractive optical element. The light source is used for emitting laser. The light source includes a substrate and an array of light emitting elements disposed on the substrate. The substrate includes a first region and a second region contiguous with the first region. The density of the light emitting elements of the first region is different from the density of the light emitting elements of the second region. The collimating element is used for collimating the laser light. The diffractive optical element is used for diffracting the laser light collimated by the collimating element to form a laser light pattern. In the structured light projector, the depth camera, and the electronic apparatus according to the embodiments of the present invention, the density of the light emitting elements in the first region is different from the density of the light emitting elements in the second region, so that the irrelevance of the laser pattern can be improved, and the speed and accuracy of obtaining the depth image of the laser pattern can be improved.
Description
Technical Field
The present invention relates to the field of imaging technologies, and in particular, to a structured light projector, a depth camera, and an electronic device.
Background
Structured light projectors, such as laser projectors, are used to project set optical patterns into a target space, and are widely used in the field of optical-based three-dimensional measurement. The structured light projector generally includes a light source, a collimating element, and a diffractive optical element, wherein the light source may be a single edge-emitting laser light source, or an area-array laser light source composed of a plurality of vertical cavity surface-emitting lasers. The structured light projector based on the single edge-emitting laser light source can emit laser patterns with high irrelevance, but the volume of the structured light projector is obviously increased along with the increase of the output power, and the uniformity of the laser patterns is poor; the structured light projector based on at least two vertical cavity surface emitting laser light sources can emit laser patterns with the same power and higher uniformity in a smaller volume, but the irrelevance of the laser patterns is lower, and the irrelevance of the laser patterns directly influences the depth image precision and the speed of acquiring the depth image.
Disclosure of Invention
The embodiment of the invention provides a structured light projector, a depth camera and an electronic device.
A structured light projector of an embodiment of the present invention includes:
a light source for emitting laser light, the light source including a substrate and a light emitting element array provided on the substrate, the substrate including a first region and a second region contiguous to the first region, a density of the light emitting elements of the first region being different from a density of the light emitting elements of the second region;
a collimating element to collimate the laser light; and
a diffractive optical element for diffracting the laser light collimated by the collimating element to form a laser light pattern.
In some embodiments, a first density of the light emitting elements in the first region is less than a second density of the light emitting elements in the second region.
In certain embodiments, the first density is zero.
In some embodiments, the density of the light emitting elements gradually increases from the first region to the second region.
In some embodiments, the array of light emitting elements is distributed in a matrix, and the light emitting elements of the second region are located on at least two sides of the light emitting elements of the first region.
In some embodiments, the array of light emitting elements is distributed in a ring shape, and the light emitting elements of the second region are disposed around the light emitting elements of the first region.
In some embodiments, the light emitting elements of the first region and the light emitting elements of the second region are individually driven to emit laser light, and the intensity of the laser light emitted by the light emitting elements of the first region is smaller than the intensity of the laser light emitted by the light emitting elements of the second region.
In some embodiments, a light emitting area of the light emitting element of the first region is smaller than a light emitting area of the light emitting element of the second region.
A depth camera according to an embodiment of the present invention includes:
the structured light projector of any of the embodiments above;
the image collector is used for collecting the laser patterns projected into the target space after passing through the diffractive optical element; and
and the processor is respectively connected with the structured light projector and the image collector and is used for processing the laser pattern to obtain a depth image.
An electronic device according to an embodiment of the present invention includes:
a housing; and
the depth camera of any of the above embodiments, the depth camera disposed within and exposed from the housing to acquire a depth image.
In the structured light projector, the depth camera, and the electronic apparatus according to the embodiments of the present invention, the density of the light emitting elements in the first region is different from the density of the light emitting elements in the second region, so that the irrelevance of the laser pattern can be improved, and the speed and accuracy of obtaining the depth image of the laser pattern can be improved.
Additional aspects and advantages of embodiments of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.
Drawings
The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:
FIG. 1 is a schematic structural view of a structured light projector according to certain embodiments of the present invention;
FIGS. 2-7 are schematic structural views of the light source of the structured light projector according to certain embodiments of the present invention;
FIGS. 8-19 are schematic illustrations of portions of collimating elements of structured light projectors according to certain embodiments of the present invention;
FIG. 20 is a schematic diagram of a depth camera in accordance with certain embodiments of the invention;
FIG. 21 is a schematic structural diagram of an electronic device in accordance with certain embodiments of the invention;
description of the main elements and symbols:
the structured light projector 100, the substrate assembly 10, the substrate 11, the heat dissipation hole 111, the circuit board 12, the via hole 121, the lens barrel 20, the accommodating cavity 21, the top 22, the bottom 23, the through hole 24, the carrier 25, the first segment structure 26, the first segment structure 27, the protective cover 30, the contact surface 31, the light hole 32, the light source 40, the light emitting surface 41, the substrate 43, the first region 432, the first sub-region 4322, the second sub-region 4324, the second region 434, the third sub-region 4342, the fourth sub-region 4344, the light emitting element 44, the collimating element 50, the first lens 51, the first light incident surface 511, the first light emitting surface 512, the second lens 52, the second light incident surface 521, the second light emitting surface 522, the third lens 53, the third light incident surface 531, the third light emitting surface 532, the fourth lens 54, the fifth lens 55, the sixth lens 56, the diffractive optical element 60, the diffractive light emitting surface 61, the diffractive incident surface 62, the, Projection window 401, collection window 402, image collector 200, processor 300, electronic device 1000, housing 500.
Detailed Description
Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are exemplary only for the purpose of illustrating the embodiments of the present invention and are not to be construed as limiting the embodiments of the present invention.
In the description of the embodiments of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of describing the embodiments of the present invention and simplifying the description, but do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the embodiments of the present invention. Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", may explicitly or implicitly include one or more of the described features. In the description of the embodiments of the present invention, "a plurality" means two or more unless specifically limited otherwise.
In the description of the embodiments of the present invention, it should be noted that, unless explicitly stated or limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; may be mechanically connected, may be electrically connected or may be in communication with each other; either directly or indirectly through intervening media, either internally or in any other suitable relationship. Specific meanings of the above terms in the embodiments of the present invention can be understood by those of ordinary skill in the art according to specific situations.
The following disclosure provides many different embodiments or examples for implementing different configurations of embodiments of the invention. In order to simplify the disclosure of embodiments of the invention, the components and arrangements of specific examples are described below. Of course, they are merely examples and are not intended to limit the present invention. Furthermore, embodiments of the invention may repeat reference numerals and/or reference letters in the various examples, which have been repeated for purposes of simplicity and clarity and do not in themselves dictate a relationship between the various embodiments and/or arrangements discussed. In addition, embodiments of the present invention provide examples of various specific processes and materials, but one of ordinary skill in the art may recognize applications of other processes and/or use of other materials.
Referring to fig. 1, a structured light projector 100 according to an embodiment of the present invention includes a substrate assembly 10, a lens barrel 20, a protective cover 30, a light source 40, a collimating element 50, and a diffractive optical element 60.
The substrate assembly 10 includes a substrate 11 and a circuit board 12 carried on the substrate 11. The material of the substrate 11 may be plastic, for example, any one or more of Polyethylene Glycol Terephthalate (PET), Polymethyl Methacrylate (PMMA), Polycarbonate (PC), and Polyimide (PI). Thus, the substrate 11 is light in weight and has sufficient support strength. The circuit board 12 may be a hard board, a soft board, or a rigid-flex board. The circuit board 12 is provided with a via 121. The light source 40 is fixed on the substrate 11 through the via 121 and electrically connected to the circuit board 12. The substrate 11 may be formed with heat dissipation holes 111, heat generated by the operation of the light source 40 or the circuit board 12 may be dissipated through the heat dissipation holes 111, and the heat dissipation holes 111 may be filled with a thermal conductive adhesive to further improve the heat dissipation performance of the substrate assembly 10.
The lens barrel 20 is disposed on the substrate assembly 10 and forms an accommodation cavity 21 together with the substrate assembly 10. The light source 40, the collimating element 50, and the diffractive optical element 60 are all housed in the housing cavity 21. The collimating element 50 and the diffractive optical element 60 are disposed in sequence on the light emitting path of the light source 40. The barrel 20 includes opposing top 22 and bottom 23 portions. The lens barrel 20 is formed with a through hole 24 penetrating the top 22 and the bottom 23. The base 23 is carried on the substrate assembly 10 and may be secured to the circuit board 12, in particular by glue. An annular bearing table 25 extends from the inner wall of the lens barrel 20 toward the center of the through hole 24, and the diffractive optical element 60 is carried on the bearing table 25.
A protective cover 30 is provided on the top portion 22, the protective cover 30 including an abutting surface 31 opposing the base plate 11. The protective cover 30 and the stage 25 respectively abut against the diffractive optical element 60 from opposite sides of the diffractive optical element 60. The abutting surface 31 is a surface of the protective cover 30 that abuts the diffractive optical element 60. The structured light projector 100 uses the protective cover 30 to abut against the diffractive optical element 60 so that the diffractive optical element 60 is accommodated in the accommodating cavity 21, and prevents the diffractive optical element 60 from falling off in the light outgoing direction.
In some embodiments, the protective cover 30 may be made of a metal material, such as nano silver wire, metallic silver wire, copper sheet, and the like. The protective cover 30 is provided with a light hole 32. The light-transmissive holes 32 are aligned with the through-holes 24. The light-transmitting hole 32 is used to emit the laser light pattern projected by the diffractive optical element 60. The aperture size of the light-transmitting hole 32 is smaller than at least one of the width or the length of the diffractive optical element 60 to confine the diffractive optical element 60 within the housing cavity 21.
In some embodiments, the protective cover 30 may be made of a light-transmissive material, such as glass, Polymethyl Methacrylate (PMMA), Polycarbonate (PC), Polyimide (PI), and the like. Since the transparent materials such as glass, PMMA, PC, and PI have excellent light transmittance, the protective cover 30 does not need to be provided with the light hole 32. In this way, the protective cover 30 can prevent the diffractive optical element 60 from coming off and prevent the diffractive optical element 60 from being exposed to the outside of the lens barrel 20, thereby providing waterproof and dustproof effects to the diffractive optical element 60.
The light source 40 is used to emit laser light. The light source 40 is carried on the substrate 11 and is received within the via 121. The size of the via hole 121 corresponds to the size of the light source 40, that is, the size of the via hole 121 is larger than the size of the light source 40, or the size of the via hole 121 is equivalent to the size of the light source 40.
In the embodiment shown in fig. 1, the light source 40 may be a Vertical Cavity Surface Emitting Laser (VCSEL). In particular, the VCSEL is a novel laser emitting light vertically from the surface, i.e. the light emitting direction of the VCSEL is perpendicular to the substrate, so that integration of a high-density two-dimensional area array can be easily achieved, higher power output can be achieved, and the VCSEL is more convenient to be integrated into a small electronic component because the VCSEL has a smaller volume than an edge-emitting laser; meanwhile, the coupling efficiency of the VCSEL and the optical fiber is high, so that a complex and expensive light beam shaping system is not needed, the manufacturing process is compatible with the light emitting diode, and the production cost is greatly reduced.
Of course, the light source 40 may also be an edge-emitting Laser (EEL), more specifically, a Distributed Feedback Laser (DFB). It can be appreciated that DFB has less temperature drift and lower cost.
Referring to fig. 2, when the light source 40 is a vertical cavity surface emitting laser, the light source 40 includes a semiconductor substrate 43 and an array of light emitting devices 44 disposed on the substrate 43, and the array of light emitting devices 44 is fixed on the substrate assembly 10 through the substrate 43. When the light source 40 is an edge emitting laser, the light source 40 includes a plurality of DFBs, the DFBs form an array of light emitting elements 44, that is, each light emitting element 44 is in a column shape, one end surface of the light emitting element 44 away from the substrate assembly 10 forms a light emitting surface 41, the laser light is emitted from the light emitting surface 41, the light emitting surface 41 faces the collimating element 50, and the light emitting surface 41 is perpendicular to the collimating optical axis of the collimating element 50. In the following description, taking an example in which the light source 40 is a vertical cavity surface emitting laser, and the light source 40 is an edge emitting laser, the arrangement of the array of the light emitting elements 44 formed of a plurality of DFBs on the substrate 11 is the same as the arrangement of the array of the light emitting elements 44 on the substrate 43.
With reference to fig. 2, the substrate 43 includes a first region 432 and a second region 434 adjoining the first region 432, and the density of the light emitting devices 44 in the first region 432 is different from the density of the light emitting devices 44 in the second region 434. In this way, the irrelevancy of the laser pattern projected into the target space by the structured light projector 100 can be improved, thereby improving the speed and accuracy of acquiring the depth image of the laser pattern.
It is to be noted that the irrelevancy of the laser pattern means that the laser pattern generated by the light beam emitted from the light emitting element 44 has high uniqueness including uniqueness of the shape, size, arrangement position, and the like of the laser pattern.
Specifically, the first region 432 is a region at the center position of the substrate 43, and the second region 434 is a region at the edge position of the substrate 43. The density of light emitting elements 44 of the first region 432 may be greater than the density of light emitting elements 44 of the second region 434 (including the case where the density of light emitting elements 44 of the second region 434 is zero); or the density of the light emitting elements 44 of the first region 432 is smaller than the density of the light emitting elements 44 of the second region 434 (including the case where the density of the light emitting elements 44 of the first region 432 is zero).
Referring to fig. 2 and 3, in some embodiments, the array of light emitting elements 44 may be arranged in a matrix. The light emitting elements 44 of the second area 434 are located on at least two sides of the light emitting elements 44 of the first area 432.
Specifically, the light emitting elements 44 of the second region 434 may be located on either side of the light emitting elements 44 of the first region 432 (as shown in FIG. 2); or the light emitting elements 44 of the second area 434 may be located on any three sides of the light emitting elements 44 of the first area 432; or the light emitting elements 44 of the second area 434 may be located on four sides of the light emitting elements 44 of the first area 432 (as shown in fig. 3).
Referring to fig. 4, in some embodiments, the array of light emitting elements 44 is distributed in a ring shape, and may be in a circular ring shape or a square ring shape. The light emitting elements 44 of the second area 434 are arranged around the light emitting elements 44 of the first area 432.
Referring to fig. 5, in some embodiments, a first density of light emitting devices 44 in the first area 432 is less than a second density of light emitting devices 44 in the second area 434. Specifically, the light emitting elements 44 in the first area 432 and the light emitting elements 44 in the second area 434 may be uniformly distributed, and the distance between the adjacent light emitting elements 44 in the first area 432 is greater than the distance between the adjacent light emitting elements 44 in the second area 434 along the direction from the first area 432 to the second area 434.
It is understood that when the structured light projector 100 emits laser light, the laser light emitted by the structured light projector 100 includes a zero-order light beam and a non-zero-order light beam because the laser light is scattered, wherein the zero-order light beam is a light beam which is converged at the center of the light emitting position after the laser light is scattered, and the non-zero-order light beam is a light beam which is transmitted to the periphery of the light emitting position after the laser light is scattered. When the intensity of the zero-order light beam is too strong, the zero-order light beam cannot be completely diffracted when being transmitted to the diffractive optical element 60, so that the intensity of the zero-order light beam emitted through the diffractive optical element 60 is too strong, which may harm the eyes of the user. In embodiments of the present invention, the first density of light-emitting elements 44 in the first region 432 is less than the second density of light-emitting elements 44 in the second region 434, which reduces the light converging to the middle of the optical path and thus reduces the intensity of the zero-order beam of the structured light projector 100.
Further, referring to FIG. 6, the first density may be zero, i.e., no light emitting elements 44 are disposed in the middle region of the substrate 43, to further reduce the intensity of the zero order beam of the structured light projector 100.
Referring again to fig. 2, in some embodiments, the density of the light emitting devices 44 gradually increases from the first region 432 to the second region 434. Specifically, the first area 432 includes a plurality of sub-areas, such as a first sub-area 4322, a second sub-area 4324, and the like, in sequence along the direction from the first area 432 to the second area 434. The second region 434 includes a plurality of sub-regions, for example, a third sub-region 4342, a fourth sub-region 4344, and the like, in order along the direction from the first region 432 to the second region 434. Here, the density of the light emitting elements 44 in the first sub-region 4322, the density of the light emitting elements 44 in the second sub-region 4324, the density of the light emitting elements 44 in the third sub-region 4342, and the density of the light emitting elements 44 in the fourth sub-region 4344 are sequentially increased, or the number of the light emitting elements 44 per unit area in the first sub-region 4322, the number of the light emitting elements 44 per unit area in the second sub-region 4324, the number of the light emitting elements 44 per unit area in the third sub-region 4342, and the number of the light emitting elements 44 per unit area in the fourth sub-region 4344 are sequentially increased.
In some embodiments, the light emitting elements 44 of the first area 432 and the light emitting elements 44 of the second area 434 are driven separately to emit laser light, and the intensity of the laser light emitted by the light emitting elements 44 of the first area 432 is less than the intensity of the laser light emitted by the light emitting elements 44 of the second area 434. In this manner, the intensity of light converging to an intermediate position in the optical path may be reduced, thereby reducing the intensity of the zero order beam of the structured light projector 100.
Referring to fig. 7, in some embodiments, the light emitting area of the light emitting device 44 in the first region 432 is smaller than the light emitting area of the light emitting device 44 in the second region 434. In this manner, light converging to an intermediate position in the optical path may be reduced, thereby reducing the intensity of the zero order beam of the structured light projector 100.
Referring again to fig. 1, the collimating element 50 is used for collimating the laser light emitted from the light source 40. The collimating element 50 is fixed to the barrel 20, and the stage 25 is located between the collimating element 50 and the diffractive optical element 60. The collimating element 50 includes one or more lenses disposed in the light-emitting path of the light source 40, and the lenses are made of glass. The lenses of the collimating element 50 can be made of glass material, so as to solve the problem that the lenses generate temperature drift when the environmental temperature changes; alternatively, the lenses of the collimating element 50 are made of plastic material, so that the cost is low and mass production is convenient.
Referring to fig. 1 and 8, in some embodiments, the collimating element 50 may only include the first lens 51, and the first lens 51 includes a first light incident surface 511 and a first light emitting surface 512 which are opposite to each other. The first light incident surface 511 is a surface of the first lens 51 close to the light source 40, and the first light emitting surface 512 is a surface of the first lens 51 close to the diffractive optical element 60. The first light incident surface 511 is a concave surface, and the first light emitting surface 512 is a convex surface. The surface type of the first lens 51 may be an aspherical surface, a spherical surface, a fresnel surface, or a binary optical surface. A diaphragm is arranged between the light source 40 and the first lens 51 for limiting the light beam.
In some embodiments, the collimating element 50 may include a plurality of lenses coaxially disposed in sequence in the light emitting path of the light source 40. The surface type of each lens can be any one of an aspheric surface, a spherical surface, a Fresnel surface and a binary optical surface.
For example: referring to fig. 1 and 9, the plurality of lenses may include a first lens 51 and a second lens 52. The first lens 51 and the second lens 52 are coaxially arranged in this order on the light emission path of the light source 40. The first lens 51 includes a first light incident surface 511 and a first light emitting surface 512 opposite to each other. The first light incident surface 511 is a surface of the first lens 51 close to the light source 40, and the first light emitting surface 512 is a surface of the first lens 51 close to the diffractive optical element 60. The second lens 52 includes a second light incident surface 521 and a second light emitting surface 522 opposite to each other. The second light incident surface 521 is a surface of the second lens 52 close to the light source 40, and the second light emitting surface 522 is a surface of the second lens 52 close to the diffractive optical element 60. The vertex of the first light emitting surface 512 is abutted against the vertex of the second light incident surface 521, the first light incident surface 511 is a concave surface, and the second light emitting surface 522 is a convex surface. The diaphragm is disposed on the second light incident surface 521 for limiting the light beam. Further, the first light emitting surface 512 and the second light incident surface 521 may be convex surfaces. Thus, the vertex of the first light emitting surface 512 is convenient to collide with the vertex of the second light incident surface 521. The curvature radius of the first light exiting surface 512 is smaller than that of the second light entering surface 521.
Referring to fig. 1 and 10, the plurality of lenses may further include a first lens 51, a second lens 52, and a third lens 53. The first lens 51, the second lens 52, and the third lens 53 are coaxially and sequentially disposed on a light emitting path of the light source 40. The first lens 51 includes a first light incident surface 511 and a first light emitting surface 512 opposite to each other. The first light incident surface 511 is a surface of the first lens 51 close to the light source 40, and the first light emitting surface 512 is a surface of the first lens 51 close to the diffractive optical element 60. The second lens 52 includes a second light incident surface 521 and a second light emitting surface 522 opposite to each other. The second light incident surface 521 is a surface of the second lens 52 close to the light source 40, and the second light emitting surface 522 is a surface of the second lens 52 close to the diffractive optical element 60. The third lens 53 includes a third light incident surface 531 and a third light emitting surface 532 opposite to each other. The third light incident surface 531 is a surface of the third lens 53 close to the light source 40, and the third light emitting surface 532 is a surface of the third lens 53 close to the diffractive optical element 60. The third light incident surface 531 is a concave surface, and the third light emitting surface 532 is a convex surface. The diaphragm is disposed on the third light emitting surface 532 and is used for limiting the light beam. Further, the first light incident surface 511 may be a convex surface, the first light emitting surface 512 is a concave surface, the second light incident surface 521 is a concave surface, and the second light emitting surface 522 is a concave surface.
In some embodiments, the collimating element 50 comprises a plurality of lenses. The plurality of lenses are sequentially disposed on a light emitting path of the light source 40, and an optical axis of at least one lens is shifted from optical axes of the other lenses. At this time, the structure of the lens barrel 20 may be one or more sections, each section being used for mounting a corresponding lens.
For example: referring to fig. 11 to 15, the collimating element 50 includes a first lens 51, a second lens 52 and a third lens 53. The first lens 51, the second lens 52, and the third lens 53 are sequentially disposed on the light emission path of the light source 40. The optical axis of the second lens 52 is offset from the optical axis of the first lens 51, the optical axis of the first lens 51 coincides with the optical axis of the third lens 53 (as shown in fig. 11), further, the optical axis of the second lens 52 may be parallel to the optical axis of the first lens 51, at this time, the structure of the lens barrel 20 may be a two-stage structure, the first stage structure 26 is used for installing the first lens 51 and the second lens 52, the second stage structure 27 is used for installing the third lens 53, the first stage structure 26 is obliquely connected to the second stage structure 27, and the second lens 52 is installed at the connection position of the first stage structure 26 and the second stage structure 27, so that the multiple lenses form a bending structure to increase the optical path length and reduce the overall height of the structured light projector 100, the inner walls of the first stage structure 26 and the second stage structure 27 are coated with a reflective coating for reflecting light, so that the light emitted by the light source 40 can sequentially pass through the first light incident surface 511, the second incident surface, A first light emitting surface 512, a second light incident surface 521, a second light emitting surface 522, a third light incident surface 531, and a third light emitting surface 532; of course, in other embodiments, the first stage structure 26 and the second stage structure 27 may also be reflective elements independent from the lens barrel 20, the reflective elements are disposed on the lens barrel 20, the reflective elements are prisms or mirrors, and the like, and the reflective elements are used for reflecting light to change the direction of the light path; alternatively, the optical axis of the first lens 51 may be shifted from the optical axis of the second lens 52, and the optical axis of the second lens 52 may coincide with the optical axis of the third lens 53 (as shown in fig. 12), and further, the optical axis of the first lens 51 may be parallel to the optical axis of the second lens 52; alternatively, the optical axis of the third lens 53 is offset from the optical axis of the first lens 51, the optical axis of the first lens 51 coincides with the optical axis of the second lens 52 (as shown in fig. 13), and further, the optical axis of the third lens 53 may be parallel to the optical axis of the first lens 51; alternatively, the optical axis of the second lens 52 is shifted from the optical axis of the first lens 51, the optical axis of the third lens 53 is shifted from the optical axis of the first lens 51, the optical axis of the second lens 52 and the optical axis of the third lens 53 are located on the same side of the optical axis of the first lens 51 (as shown in fig. 14), further, the optical axis of the first lens 51 may be parallel to the optical axis of the second lens 52, the optical axis of the first lens 51 is parallel to the optical axis of the third lens 53, and the optical axis of the second lens 52 is parallel to the optical axis of the third lens 53; alternatively, the optical axis of the second lens 52 is offset from the optical axis of the first lens 51, the optical axis of the third lens 53 is offset from the optical axis of the first lens 51, the optical axis of the second lens 52 and the optical axis of the third lens 53 are located on opposite sides of the optical axis of the first lens 51 (as shown in fig. 15), and further, the optical axis of the first lens 51 may be parallel to the optical axis of the second lens 52, the optical axis of the first lens 51 may be parallel to the optical axis of the third lens 53, and the optical axis of the second lens 52 may be parallel to the optical axis of the third lens 53.
Preferably, the optical axis of the second lens 52 is shifted from the optical axis of the first lens 51, the optical axis of the third lens 53 is shifted from the optical axis of the first lens 51, and the optical axis of the second lens 52 and the optical axis of the third lens 53 are located on opposite sides of the optical axis of the first lens 51. Thus, the multiple lenses form a bending structure, which is beneficial to increase the optical path, increase the focal length, and reduce the height of the structured light projector 100. Of course, the collimating element 50 may also include more lenses, for example, referring to fig. 16, the collimating element 50 includes a first lens 51, a second lens 52, a third lens 53, a fourth lens 54, a fifth lens 55, and a sixth lens 56. The first lens 51, the second lens 52, the third lens 53, the fourth lens 54, the fifth lens 55, and the sixth lens 56 are sequentially disposed on the light emission optical path of the light source 40. The optical axis of the second lens 52 is shifted from the optical axis of the first lens 51, the optical axis of the third lens 53 is shifted from the optical axis of the first lens 51, the optical axis of the second lens 52 and the optical axis of the third lens 53 are located on the opposite side of the optical axis of the first lens 51, the optical axis of the fourth lens 54 is overlapped with the optical axis of the second lens 52, the optical axis of the fifth lens 55 is overlapped with the optical axis of the third lens 53, and the optical axis of the sixth lens 56 is overlapped with the optical axis of the first lens 51.
It should be noted that in the structured light projector 100 shown in fig. 12 to 16, the structure of the lens barrel 20 is the same as or similar to the structure of the lens barrel 20 shown in fig. 11, and the structure of the lens barrel 20 can be a one-stage or multi-stage structure, which is not described herein again.
In some embodiments, the collimating element 50 comprises a plurality of lenses, and the optical centers of at least two of the lenses are located on the same plane perpendicular to the first direction, which is the direction from the light source 40 to the diffractive optical element 60.
For example: referring to fig. 17 to 19, the collimating element 50 includes a first lens 51, a second lens 52 and a third lens 53. The optical center of the first lens 51 and the optical center of the second lens 52 are located on the same plane (as shown in fig. 17), and the optical axis of the first lens 51 and the optical axis of the second lens 52 may be located on the opposite side of the optical axis of the third lens 53; alternatively, the optical center of the second lens 52 and the optical center of the third lens 53 may be located on the same plane (as shown in fig. 18), and the optical axis of the second lens 52 and the optical axis of the third lens 53 may be located on the opposite side of the optical axis of the first lens 51; alternatively, the optical center of the first lens 51 and the optical center of the third lens 53 are located on the same plane; alternatively, the optical center of the first lens 51, the optical center of the second lens 52, and the optical center of the third lens 53 are all located on the same plane (as shown in fig. 19). Further, the optical axis of the first lens 51 may be parallel to the optical axis of the second lens 52, the optical axis of the first lens 51 may be parallel to the optical axis of the third lens 53, and the optical axis of the second lens 52 may be parallel to the optical axis of the third lens 53.
Referring to fig. 1 again, the diffractive optical element 60 is used for diffracting the laser light collimated by the collimating element 50 to form a laser pattern. The diffractive optical element 60 includes opposing diffractive exit and entrance faces 61, 62. The protective cover 30 can be adhered to the top 22 by glue, the contact surface 31 contacts with the diffraction exit surface 61, and the diffraction incident surface 62 contacts with the carrying platform 25, so that the diffractive optical element 60 will not fall off from the receiving cavity 21 along the light exit direction. The diffractive optical element 60 may be made of glass or composite plastic (e.g., PET).
When the structured light projector 100 described above is assembled, the collimating element 50 and the substrate assembly 10 to which the light source 40 is attached are inserted into the through hole 24 in this order from the bottom 23 of the lens barrel 20 along the optical path. The light source 40 may be mounted on the substrate assembly 10, and then the substrate assembly 10 mounted with the light source 40 is fixed to the bottom 23. The diffractive optical element 60 is put into the through hole 24 from the top 22 against the direction of the optical path and carried on the carrier table 25, and then the protective cover 30 is mounted such that the diffractive exit surface 61 of the diffractive optical element 60 interferes with the protective cover 30 and the diffractive entrance surface 62 interferes with the carrier table 25. The structured light projector 100 is simple in structure and convenient to assemble.
Referring to fig. 20, a depth camera 400 according to an embodiment of the present invention includes the structured light projector 100, the image collector 200, and the processor 300 according to any of the above embodiments. The image collector 200 is used to collect the laser pattern projected into the target space via the diffractive optical element 50. The processor 300 is connected to the structured light projector 100 and the image collector 200, respectively. The processor 300 is used to process the laser pattern to obtain a depth image.
Specifically, the structured light projector 100 projects the laser light pattern projected into the target space outward through the projection window 401, and the image acquirer 200 acquires the laser light pattern modulated by the target object through the acquisition window 402. The image collector 200 may be an infrared camera, and the processor 300 calculates a deviation value between each pixel point in the laser pattern and each corresponding pixel point in the reference pattern by using an image matching algorithm, and further obtains a depth image of the laser pattern according to the deviation value. The Image matching algorithm may be a Digital Image Correlation (DIC) algorithm. Of course, other image matching algorithms may be employed instead of the DIC algorithm.
In the depth camera 400 according to the embodiment of the present invention, the density of the light emitting elements 44 in the first region 432 is different from the density of the light emitting elements 44 in the second region 434, so that the irrelevance of the laser pattern projected into the target space by the structured light projector 100 can be improved, and the speed and accuracy of acquiring the depth image of the laser pattern can be improved.
Referring to fig. 21, an electronic device 1000 according to an embodiment of the invention includes a housing 500 and the depth camera 400 according to the embodiment. The depth camera 400 is disposed within the housing 500 and exposed from the housing 500 to acquire a depth image. The electronic device 1000 includes, but is not limited to, a mobile phone, a tablet computer, a notebook computer, a smart bracelet, a smart watch, a smart helmet, smart glasses, and the like. The housing 500 may provide protection for the depth camera 400 from dust, water, falls, etc.
In the electronic device 1000 according to the embodiment of the present invention, the density of the light emitting elements 44 in the first region 432 is different from the density of the light emitting elements 44 in the second region 434, so that the irrelevance of the laser pattern projected into the target space by the structured light projector 100 can be improved, and the speed and the accuracy of acquiring the depth image of the laser pattern can be improved.
In the description herein, references to the description of the terms "one embodiment," "some embodiments," "an illustrative embodiment," "an example," "a specific example" or "some examples" or the like mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and not to be construed as limiting the present invention, and those skilled in the art can make changes, modifications, substitutions and alterations to the above embodiments within the scope of the present invention.
Claims (9)
1. A structured light projector, comprising:
the light source is a vertical cavity surface emitting laser, the light source is used for emitting laser, the light source comprises a substrate and a light emitting element array arranged on the substrate, the substrate sequentially comprises a first area and a second area connected with the first area from the center to the edge, and the first density of the light emitting elements in the first area is smaller than the second density of the light emitting elements in the second area;
a collimating element for collimating the laser light, the collimating element comprising a plurality of lenses, an optical axis of at least one of the lenses being offset with respect to optical axes of other of the lenses; and
a diffractive optical element for diffracting the laser light collimated by the collimating element to form a laser light pattern.
2. The structured light projector of claim 1 wherein the first density is zero.
3. The structured light projector of claim 1 wherein the density of the light emitting elements increases from the first region to the second region.
4. The structured light projector of claim 1 wherein the array of light emitting elements is distributed in a matrix, the light emitting elements of the second region being located on at least two sides of the light emitting elements of the first region.
5. The structured light projector of claim 1 wherein the array of light emitting elements is distributed in a ring, the light emitting elements of the second region being disposed around the light emitting elements of the first region.
6. The structured light projector of claim 1 wherein the light emitting elements of the first area and the light emitting elements of the second area are separately driven to emit laser light, the intensity of the laser light emitted by the light emitting elements of the first area being less than the intensity of the laser light emitted by the light emitting elements of the second area.
7. The structured light projector of claim 1 wherein the light emitting elements of the first region have a light emitting area that is less than a light emitting area of the light emitting elements of the second region.
8. A depth camera, comprising:
the structured light projector of any one of claims 1 to 7;
the image collector is used for collecting the laser patterns projected into the target space after passing through the diffractive optical element; and
and the processor is respectively connected with the structured light projector and the image collector and is used for processing the laser pattern to obtain a depth image.
9. An electronic device, comprising:
a housing; and
the depth camera of claim 8, disposed within and exposed from the housing to acquire a depth image.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810200423.6A CN108490628B (en) | 2018-03-12 | 2018-03-12 | Structured light projector, depth camera and electronic device |
| PCT/CN2019/075378 WO2019174434A1 (en) | 2018-03-12 | 2019-02-18 | Structured light projector, depth camera, and electronic device |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201810200423.6A CN108490628B (en) | 2018-03-12 | 2018-03-12 | Structured light projector, depth camera and electronic device |
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| CN109120837B (en) * | 2018-10-31 | 2020-05-01 | Oppo广东移动通信有限公司 | Image acquisition method, image acquisition device, structured light assembly and electronic device |
| CN109643051B (en) * | 2018-11-24 | 2022-03-11 | 深圳阜时科技有限公司 | Light source structure, optical projection module, sensing device and equipment |
| WO2020103166A1 (en) * | 2018-11-24 | 2020-05-28 | 深圳阜时科技有限公司 | Light source structure, optical projection module and sensing device and apparatus |
| CN111246073B (en) * | 2020-03-23 | 2022-03-25 | 维沃移动通信有限公司 | Imaging device, method and electronic equipment |
| CN114727089A (en) * | 2022-02-28 | 2022-07-08 | 深圳博升光电科技有限公司 | Structured light system, electronic equipment with structured light system and control method |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103097805A (en) * | 2010-09-10 | 2013-05-08 | 皇家飞利浦电子股份有限公司 | Arrangement for spot illumination |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| WO2009093228A2 (en) * | 2008-01-21 | 2009-07-30 | Prime Sense Ltd. | Optical designs for zero order reduction |
| US9778476B2 (en) * | 2014-11-03 | 2017-10-03 | Aquifi, Inc. | 3D depth sensor and projection system and methods of operating thereof |
| CN106568396A (en) * | 2016-10-26 | 2017-04-19 | 深圳奥比中光科技有限公司 | Laser projector and depth camera thereof |
| CN106569382B (en) * | 2016-10-26 | 2018-07-06 | 深圳奥比中光科技有限公司 | Laser-projector and its depth camera |
| CN106997603B (en) * | 2017-05-19 | 2020-04-17 | 深圳奥比中光科技有限公司 | Depth camera based on VCSEL array light source |
| CN107490930B (en) * | 2017-09-01 | 2020-12-18 | 深圳奥比中光科技有限公司 | Laser projection device with suppression of zero-order diffraction |
-
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| CN103097805A (en) * | 2010-09-10 | 2013-05-08 | 皇家飞利浦电子股份有限公司 | Arrangement for spot illumination |
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