Linear laser projector, camera assembly and electronics

Abstract

This application provides a linear laser projector, a camera assembly, and an electronic device. The laser projector includes a substrate assembly, multiple laser light sources, and diffractive optical elements. Multiple laser light sources are disposed on the substrate assembly for emitting laser light. The multiple laser light sources are arranged in N rows along a direction perpendicular to a predetermined straight line, wherein each row includes multiple laser light sources arranged along the predetermined straight line. The diffractive optical elements are used to diffuse the laser light emitted by the multiple laser light sources along the predetermined straight line, such that each row of laser light sources projects M linear projection patterns extending along the predetermined straight line, where N and M are positive integers greater than 1, and the N×M linear projection patterns are arranged at intervals along the direction perpendicular to the predetermined straight line. The M linear projection patterns projected by at least one row of laser light sources are alternately arranged with the M linear projection patterns projected by at least another row of laser light sources along the direction perpendicular to the predetermined straight line.

Description

[0001] This application is a divisional application of Chinese patent application No. CN202210977419.7, filed on August 15, 2022, entitled "Linear Laser Projector, Camera Assembly and Electronic Device". Technical Field

[0002] This application relates to the field of imaging technology, and more specifically, to a laser projector and a camera assembly and electronic device having therein. Background Technology

[0003] With the widespread adoption of structured light, line-line laser projection systems are increasingly used for depth detection and 3D sensing in industrial and consumer electronics sectors. This necessitates narrower line widths, higher uniformity, and higher brightness in line-line lasers. Simultaneously, systems are becoming increasingly miniaturized. Traditional line-line laser projection systems often use single-mode laser diodes (LDs) as the light source for the line. However, due to the excellent monochromaticity and coherence of lasers, when LD light illuminates the rough surface of a typical object, interference creates speckle patterns on the surface, resulting in a granular structure within the line spot. This reduces the line quality and directly impacts the calculation results of depth detection and 3D sensing. Currently, conventional line-line lasers struggle to meet application requirements in terms of divergence angle, spot uniformity, and the sharpness of the spot edge cutoff. Furthermore, conventional line-line lasers also struggle to meet the specific energy distribution requirements of certain application scenarios.

[0004] Therefore, there is a need for a linear laser projector that can easily achieve a preset light intensity distribution (uniform or non-uniform) according to application requirements.

[0005] Application content

[0006] The summary of this application introduces a series of simplified concepts, which will be further explained in detail in the detailed description section. This summary is not intended to limit the key features and essential technical features of the claimed technical solution, nor is it intended to determine the scope of protection of the claimed technical solution.

[0007] The first aspect of this application provides a linear laser projector, comprising:

[0008] Substrate assembly;

[0009] Multiple laser light sources are disposed on the substrate assembly for emitting laser light. The multiple laser light sources are arranged in N rows along a direction perpendicular to a predetermined straight line, wherein each row includes multiple laser light sources arranged along the predetermined straight line.

[0010] A diffractive optical element is used to diffuse the laser emitted by the plurality of laser sources along the predetermined straight line direction to form N×M linear projection patterns extending along the predetermined straight line direction, wherein N is a positive integer and M is a positive integer greater than 1, and the N×M linear projection patterns are arranged at intervals along a direction perpendicular to the predetermined straight line direction.

[0011] According to this application, a diffractive optical element can project a linear projection pattern from a laser source. The projection patterns from multiple laser sources are superimposed and staggered along a predetermined straight line to form the final linear projection pattern. When using a diffractive optical element to form a linear pattern, the energy distribution (e.g., uniform or non-uniform) of the linear projection pattern can be easily controlled to ensure that the energy distribution of the final projection pattern meets preset energy distribution requirements. Furthermore, by adjusting the values ​​of M and N, different numbers of linear patterns can be obtained, as well as different field-of-view angles along directions perpendicular to the predetermined straight line can be achieved.

[0012] Optionally, the plurality of laser light sources are arranged in N rows at approximately equal intervals on the substrate assembly along a direction perpendicular to the predetermined straight line, wherein N is greater than 1.

[0013] According to this application, the arrangement of multiple laser light sources is simple.

[0014] Optionally, in each row of the laser light source:

[0015] The number of laser sources is 7 to 25, and / or

[0016] The multiple laser sources are distributed at approximately equal intervals.

[0017] Optionally, in each row of the laser light source:

[0018] The distance between two adjacent laser sources is 20 μm to 40 μm, and / or

[0019] The total width of the distribution of the plurality of laser sources is 150μm to 600μm.

[0020] Optionally, the field of view of the linear projection pattern projected by the laser emitted by a single laser source is 40° to 130° along the set straight line direction.

[0021] According to this application, the parameters of the laser projector are set reasonably.

[0022] Optionally, the diffractive optical element is parallel to the substrate assembly, and the air gap between the laser source and the diffractive optical element is 2 mm to 5.5 mm.

[0023] According to this application, diffractive optical elements can have built-in collimation functions.

[0024] Optionally, the linear laser projector further includes a collimating lens disposed between the laser source and the diffractive optical element.

[0025] Furthermore, the focal length of the collimating lens is 2mm to 5.5mm.

[0026] According to this application, when the diffractive optical element does not have a collimation function, the light emitted by the laser source is collimated by the collimating lens.

[0027] Optionally, the laser source is a vertical cavity surface-emitting laser element.

[0028] According to this application, the laser source is a vertical cavity surface-emitting laser element, which can make the projector smaller in size.

[0029] Optionally, the diffractive optical element comprises a micro / nano structure with 2, 4, or 8 steps.

[0030] According to this application, the processing precision of the diffractive optical element can meet the projection requirements.

[0031] Optionally, each of the linear projection patterns includes transition regions at both ends and an intermediate region between the two transition regions, and the linear laser projector is configured such that the projection angle of the transition regions is 2° to 8°, and the non-uniformity of the intensity of the projected light in the intermediate region is less than 30%.

[0032] When it is necessary to project a single line with uniform light intensity distribution, the laser projector according to this application can project a single line with uniform light spot and sharp cutoff edge.

[0033] Optionally, the diffractive optical element is configured such that the intensity distribution of the projected light of each of the linear projection patterns satisfies a preset intensity distribution curve.

[0034] Furthermore, each of the linear projection patterns includes transition regions at both ends and a middle region located between the two transition regions, and the linear laser projector is configured such that the intensity of the projected light in the middle region is proportional to 1 / (cosα). a The normalized intensity distribution, where a is a real number in the range of (0, 1.5), and α is the diffraction angle of each point on the linear projection pattern.

[0035] The laser projector according to this application can project a straight line with an energy distribution that meets the preset energy distribution requirements.

[0036] Optionally, the linear laser projector is configured such that each row of the laser light source projects M linear projection patterns.

[0037] In this application, a laser light source projects M straight lines, and the design of the diffractive optical element is simplified.

[0038] Optionally, N is greater than 1, and the M linear projection patterns projected by at least one row of the N rows of laser light sources are staggered with the M linear projection patterns projected by at least another row of the N rows of laser light sources in a direction perpendicular to the set straight line direction.

[0039] further,

[0040] Let the q-th linear projection pattern projected by the laser light source in the p-th row be denoted as line pq, where p and q are integers, 1≤p≤N, 1≤q≤M.

[0041] The linear laser projector is configured such that the N×M linear projection patterns have the following relationship:

[0042] N lines pq with the same q value are adjacent to each other in a direction perpendicular to the defined straight line.

[0043] The p values ​​of the N lines pq with the same q value are arranged in reverse order of the row number of the laser source along a direction perpendicular to the set straight line.

[0044] According to this application, the regular staggered arrangement of N×M straight lines is beneficial for simplifying the design of diffractive optical elements and troubleshooting.

[0045] Optionally,

[0046] The plurality of laser light sources are arranged in N rows at equal intervals on the substrate assembly along a direction perpendicular to the predetermined straight line, and the diffractive optical elements are parallel to the substrate assembly.

[0047] The structural parameters of the laser projector satisfy the following formula (1):

[0048]

[0049] Where D is the minimum period of the diffractive optical element along the direction perpendicular to the set straight line, λ is the wavelength of the laser, h is the distance between two adjacent rows of the laser source along the direction perpendicular to the set straight line, and G is the air gap between the laser source and the diffractive optical element.

[0050] In this application, when the diffractive optical element has a built-in collimation function, the effect of the above-mentioned regular staggered arrangement of the diffractive optical element can be achieved by designing the diffractive optical element according to formula (1). At the same time, multiple field angles of N×M diffraction lines along the direction perpendicular to the set straight line can also be determined.

[0051] Alternatively,

[0052] The plurality of laser light sources are arranged in N rows at equal intervals on the substrate assembly along a direction perpendicular to the predetermined straight line. The linear laser projector further includes a collimating lens disposed between the laser light sources and the diffractive optical element.

[0053] The structural parameters of the laser projector satisfy the following formula (2):

[0054]

[0055] Where D is the minimum period of the diffractive optical element along the direction perpendicular to the set straight line, λ is the wavelength of the laser, h is the distance between two adjacent rows of the laser source along the direction perpendicular to the set straight line, and f is the focal length of the collimating lens.

[0056] In this application, when the diffractive optical element does not have a collimation function, the effect of the above-mentioned regular staggered arrangement of the diffractive optical element can be achieved by designing the diffractive optical element according to formula (2). At the same time, multiple field angles of N×M diffraction lines along the direction perpendicular to the set straight line can also be determined.

[0057] Optionally, N is greater than 1, and the M linear projection patterns projected by any row of the laser light sources in the N rows are adjacent along a direction perpendicular to the set straight line direction.

[0058] further,

[0059] Let the q-th linear projection pattern projected by the laser light source in the p-th row be denoted as line pq, where p and q are integers, 1≤p≤N, 1≤q≤M.

[0060] The linear laser projector is configured such that the N×M linear projection patterns have the following relationship:

[0061] M lines pq with the same p value are adjacent to each other in a direction perpendicular to the set straight line direction;

[0062] The p values ​​of the N lines pq with the same q value are arranged in reverse order of the row number of the laser source along a direction perpendicular to the set straight line.

[0063] According to this application, the N×M straight lines are arranged regularly without intersecting each other, which helps to simplify the design of diffractive optical elements and troubleshoot malfunctions.

[0064] Optionally,

[0065] The plurality of laser light sources are arranged in N rows at equal intervals on the substrate along a direction perpendicular to the predetermined straight line, and the diffractive optical elements are parallel to the substrate assembly.

[0066] The structural parameters of the laser projector satisfy the following formula (3):

[0067]

[0068] Where D is the minimum period of the diffractive optical element along the direction perpendicular to the set straight line, λ is the wavelength of the laser, h is the distance between two adjacent rows of the laser source along the direction perpendicular to the set straight line, and G is the air gap between the laser source and the diffractive optical element.

[0069] In this application, when the diffractive optical element has a built-in collimation function, the effect of the above-mentioned regular, non-intersecting arrangement of the diffractive optical element can be achieved by designing the diffractive optical element according to formula (3). At the same time, multiple field angles of N×M diffraction lines along the direction perpendicular to the set straight line can also be determined.

[0070] Alternatively,

[0071] The plurality of laser light sources are arranged in N rows at equal intervals on the substrate along a direction perpendicular to the predetermined straight line. The linear laser projector also includes a collimating lens, which is disposed between the laser light sources and the diffractive optical element.

[0072] The structural parameters of the laser projector satisfy the following formula (4):

[0073]

[0074] Where D is the minimum period of the diffractive optical element along the direction perpendicular to the set straight line, λ is the wavelength of the laser, h is the distance between two adjacent rows of the laser source along the direction perpendicular to the set straight line, and f is the focal length of the collimating lens.

[0075] In this application, when the diffractive optical element does not have a collimation function, the effect of the above-mentioned regular, non-intersecting arrangement of the diffractive optical element can be achieved by designing the diffractive optical element according to formula (4). At the same time, multiple field angles of N×M diffraction lines along the direction perpendicular to the set straight line can also be determined.

[0076] Optionally, N=1, and the structural parameters of the laser projector satisfy the following formula (5):

[0077]

[0078] Where D is the minimum period of the diffractive optical element along the direction perpendicular to the set straight line, λ is the wavelength of the laser, and θv is the field of view angle of two adjacent lines in the M linear projection patterns along the direction perpendicular to the set straight line.

[0079] According to this application, when N=1, there is a corresponding relationship between the structural parameters of the diffractive optical element and the field of view of the M lines.

[0080] A second aspect of this application provides a camera assembly comprising:

[0081] The aforementioned linear laser projector;

[0082] An image acquisition device is used to acquire a laser image formed by the pattern projected by the linear laser projector; and

[0083] A processor for processing the laser image to obtain a depth image.

[0084] The camera assembly according to this application can easily project a line with a light intensity distribution that meets preset light intensity distribution requirements (e.g., uniform or non-uniform) according to application needs, and capture and process the laser image formed by the line. Simultaneously, by adjusting the values ​​of M and N, different numbers of lines can be obtained, as well as different field-of-view angles along directions perpendicular to the set straight line.

[0085] A third aspect of this application provides an electronic device comprising:

[0086] The outer shell; and

[0087] The camera assembly described above is disposed to and exposed from the housing to obtain depth images.

[0088] The camera assembly according to this application can easily project a straight line with a light front distribution that meets preset light intensity distribution requirements (e.g., uniform or non-uniform) according to application needs, and capture and process the laser image formed by the straight line. Simultaneously, by adjusting the values ​​of M and N, different numbers of straight lines can be obtained, as well as different field-of-view angles along directions perpendicular to the set straight line. Attached Figure Description

[0089] The following drawings, which are incorporated herein by reference and are used to understand this application, illustrate embodiments of the application and their descriptions to explain the principles of the application. In the drawings:

[0090] Figure 1 This is a schematic diagram of the structure of a linear laser projector according to the first preferred embodiment of this application;

[0091] Figure 2 for Figure 1 A schematic diagram of the projection pattern of a single laser source from a linear laser projector;

[0092] Figure 3 for Figure 1 A schematic diagram of a line laser light source projecting a pattern from a linear laser projector;

[0093] Figure 4 for Figure 3 The diagram illustrates the projection effect of a line of laser light sources. For illustrative purposes, the linear projection pattern formed by multiple superimposed individual laser light sources is decomposed in space.

[0094] Figure 5 This is an explanatory diagram of the arrangement of a row of laser light sources in a linear laser projector according to a specific embodiment of this application, wherein there are 9 laser light sources;

[0095] Figure 6 for Figure 5 A simulation diagram of a linear projection pattern projected by a single laser light source, with a projection distance of 300mm.

[0096] Figure 7 for Figure 5 A simulation diagram of a linear projection pattern projected by a line of laser light sources, with a projection distance of 300mm.

[0097] Figure 8 for Figure 5 A simulation diagram of the energy distribution of a line-shaped projection pattern projected by a single laser source, where the energy values ​​are the energies of each diffraction order at infinity.

[0098] Figure 9 for Figure 5 A simulation diagram of the energy distribution of a linear projection pattern projected by a line of laser light sources, where the energy values ​​are the energies of each diffraction order at infinity.

[0099] Figure 10 This is an explanatory diagram showing the arrangement of all laser light sources in a linear laser projector according to a specific embodiment of this application;

[0100] Figure 11 for Figure 10 A simulation diagram of a linear projection pattern projected by a single laser light source, with a projection distance of 300mm.

[0101] Figure 12 for Figure 10 A simulation diagram of a linear projection pattern projected by all laser light sources in the image, with a projection distance of 300mm.

[0102] Figure 13 This is an explanatory diagram showing the arrangement of all laser light sources in a linear laser projector according to yet another specific embodiment of this application;

[0103] Figure 14 for Figure 13 A simulation diagram of a linear projection pattern projected by a single laser light source, with a projection distance of 300mm.

[0104] Figure 15 for Figure 13 A simulation diagram of a linear projection pattern projected by all laser light sources in the image, with a projection distance of 300mm.

[0105] Figure 16 This is a schematic diagram of a linear laser projector, a variant of the first preferred embodiment of this application.

[0106] Figure 17 This is a schematic diagram of the structure of a linear laser projector according to the second preferred embodiment of this application;

[0107] Figure 18 This is an explanatory diagram showing the arrangement of all laser light sources in a linear laser projector according to another specific embodiment of this application;

[0108] Figure 19 for Figure 18 A simulation diagram of a linear projection pattern projected by a single laser light source, with a projection distance of 300mm.

[0109] Figure 20 for Figure 18 A simulation diagram of a linear projection pattern projected by all laser light sources in the image, with a projection distance of 300mm;

[0110] Figure 21 for Figure 18 A simulation diagram of the energy distribution of a linear projection pattern projected by a single laser source, where the energy values ​​are the energies of each diffraction order at infinity.

[0111] Figure 22 for Figure 21 A simulation diagram of the energy distribution of another linear projection pattern projected by a single laser source, where the energy values ​​are the energies of each diffraction order at infinity;

[0112] Figure 23 To and Figure 21 A simulation diagram of the energy distribution of a linear projection pattern projected by the entire row of laser light sources corresponding to a single laser light source, where the energy values ​​are the energy of each diffraction order at infinity.

[0113] Figure 24 For Figure 22 A simulation diagram of the energy distribution of another linear projection pattern projected by the entire row of laser light sources corresponding to a single laser light source, where the energy values ​​are the energy of each diffraction order at infinity.

[0114] Figure 25 for Figure 20 A simulation diagram of the energy distribution of the 65D1 linear projection pattern, where the energy values ​​are the energies of each diffraction order at infinity.

[0115] Figure 26 for Figure 20 A simulation diagram of the energy distribution of the 65B1 linear projection pattern, where the energy values ​​are the energies of each diffraction order at infinity.

[0116] Figure 27 for Figure 20 A simulation diagram of the energy distribution of the 65D2 linear projection pattern, where the energy values ​​are the energies of each diffraction order at infinity.

[0117] Figure 28 for Figure 20 A simulation diagram of the energy distribution of the 65B2 linear projection pattern, where the energy values ​​are the energies of each diffraction order at infinity.

[0118] Explanation of reference numerals in the attached figures:

[0119] 10: Substrate Assembly

[0120] 20: Laser source

[0121] 21 / 21A / 21B / 21C / 21D: A line of laser light sources

[0122] 25: Laser beam

[0123] 30: Diffractive optical elements

[0124] 40: Collimating lens

[0125] 50: Projection screen

[0126] 60: A linear projection pattern projected by a single laser light source.

[0127] 65 / 65A1 / 65A2 / 65B1 / 65B2 / 65C1 / 65C2 / 65D1 / 65D2: A linear projection pattern formed by a line of laser light sources.

[0128] 100: Linear laser projector Detailed Implementation

[0129] The following description provides numerous specific details to offer a more thorough understanding of this application. However, it will be apparent to those skilled in the art that this application can be practiced without one or more of these details. In other instances, certain technical features well-known in the art have not been described to avoid confusion with this application.

[0130] To fully understand this application, a detailed description will be provided in the following description. It should be understood that these embodiments are provided so that the disclosure of this application is thorough and complete, and that the concept of these exemplary embodiments is fully conveyed to those skilled in the art. Obviously, the implementation of the embodiments of this application is not limited to the specific details familiar to those skilled in the art. Preferred embodiments of this application are described in detail below; however, in addition to these detailed descriptions, this application may have other embodiments.

[0131] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms “comprising” and / or “including” are used in this specification, they indicate the presence of features, integrals, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or combinations thereof.

[0132] Ordinal numbers such as “first” and “second” used in this application are merely identifiers and have no other meaning, such as a specific order. Moreover, for example, the term “first component” does not imply the existence of a “second component”, and the term “second component” does not imply the existence of a “first component”.

[0133] Exemplary embodiments according to this application will now be described in more detail with reference to the accompanying drawings.

[0134] The first aspect of this application provides a linear laser projector.

[0135] like Figure 1As shown, in a first preferred embodiment, the linear laser projector 100 includes a substrate assembly 10, a plurality of laser light sources 20, and a diffractive optical element 30. The plurality of laser light sources 20 are disposed on the substrate assembly 10 and are used to emit laser light. The plurality of laser light sources 20 are arranged in N rows (N is a positive integer, N=4 in the illustrated embodiment) along a direction Y perpendicular to a predetermined straight line X, wherein each row of laser light sources 21 includes a plurality of laser light sources 20 arranged along the predetermined straight line X. The diffractive optical element 30 is used to diffuse the laser light emitted by the plurality of laser light sources 20 along the predetermined straight line X to form N×M (M is a positive integer greater than 1, M=2 in the illustrated embodiment) linear projection patterns 65 extending along the predetermined straight line X, wherein the N×M linear projection patterns 65 are arranged at intervals along a direction Y perpendicular to the predetermined straight line X.

[0136] Specifically, such as Figure 2 As shown, one of the laser sources 20 of the linear laser projector 100 can emit a laser beam 25. The diffractive optical element 30 is configured such that the laser beam 25, after passing through the diffractive optical element 30, forms M linear projection patterns 60 on the projection screen 50. Alternatively, the diffractive optical element 30 is configured to cause the laser emitted by a single laser source 20 to diffuse in a linear pattern along a predetermined straight direction X, while simultaneously replicating this linear pattern extending along the X direction into N mutually spaced lines along the Y direction. The field of view (FOV) of the linear projection pattern 60 projected by the laser emitted by a single laser source 20 along the X direction is θs, and the field of view (FOV) of two adjacent linear projection patterns 60 along the Y direction is θv. An air gap G exists between the laser source 20 and the diffractive optical element 30.

[0137] Taking a linear projection pattern 60 projected by a single laser light source 20 as an example, such as Figure 3 and Figure 4 As shown, when each row of laser light sources 21 in the linear laser projector 100 includes multiple laser light sources 20 arranged at intervals along a predetermined straight line direction X, each laser light source 20 in the same row forms its own linear projection pattern 60. The multiple linear projection patterns 60 in the same row are then spatially superimposed to form a superimposed linear projection pattern 65. The multiple linear projection patterns 60 are staggered relative to each other in the predetermined straight line direction X, making the superposition result similar to extending the linear projection pattern 60 of a single laser light source 20 along the predetermined straight line direction X. Therefore, the linear laser projector 100 is configured such that each row of laser light sources 21 projects M linear projection patterns 65.

[0138] The field of view (FOV) of the linear projection pattern 60 projected by a single laser source 20 is θs. The linear projection pattern 65 formed by the superposition of multiple laser source 20 laser source linear projection patterns 60 has a field of view θf, where θf > θs. It can be understood that the larger the total width L of the distribution of multiple laser source 20s in the same row, the larger the field of view θf of the linear projection pattern 65.

[0139] The light intensity distribution characteristics of the linear projection pattern 60 or 65 are controlled by the diffractive optical element 30. The diffractive optical element 30 can be configured to make the light intensity distribution of the linear projection pattern 60 as uniform as possible. Figure 4 As shown, multiple linear projection patterns 60 are staggered along a predetermined straight direction X, resulting in a greater number of individual linear projection patterns 60 participating in the superposition of the superimposed linear projection patterns 65 in the middle portion and a smaller number of individual linear projection patterns 60 participating in the superposition in the portions at the ends. Therefore, the light intensity distribution curve C of the superimposed linear projection patterns 65 is approximately trapezoidal. Figure 4 As shown, each linear projection pattern 65 includes transition regions at both ends (the field of view of the transition regions is θb) and a middle region located between the two transition regions (the field of view of the middle region is θu). The light intensity of the middle region (where there are more individual linear projection patterns 60 participating in the superposition) is higher than that of the transition regions (where there are fewer individual linear projection patterns 60 participating in the superposition). The light intensity of the middle region is basically uniformly distributed, while the light intensity of the transition regions decreases towards the ends. The field of view has the following quantitative relationship:

[0140] θb = arctg(L / G),

[0141] θf = θs + θb

[0142] θu=θs-θb.

[0143] In this application, preferably, the linear laser projector 100 is configured such that the projection angle (i.e., field of view θb) of the transition region of each linear projection pattern 65 is 2° to 8°, and the non-uniformity of the intensity of the projected light in the middle region is less than 30%.

[0144] For example, such as Figures 5 to 9 As shown, each row of laser light sources 21 includes 9 laser light sources 20, which are evenly spaced and have a total distribution width L of 500 μm (see [reference]). Figure 5 The air gap G between the laser source 20 and the diffractive optical element 30 is 5 mm. The field of view θs of the linear projection pattern 60 projected by the laser emitted by a single laser source 20 is 120° (see...). Figure 6The intensity (energy) distribution of the linear projection pattern 60 projected by the laser emitted from a single laser source 20 is as follows: Figure 8 As shown. When the projected light from 9 laser sources 20 is superimposed, it will... Figure 6 and Figure 7 Comparing the two, it can be seen that the field of view of the superimposed linear projection pattern 65 is significantly greater than 120°. The light intensity (energy) distribution of the superimposed linear projection pattern 65 is as follows: Figure 9 As shown. Figure 8 and Figure 9 Comparative analysis shows that the uniformity of light intensity is significantly improved after multi-point superposition. The linewidth angle of the linear projection patterns 60 and 65 is less than 0.05°.

[0145] In practical applications, cameras typically capture a line at close range (e.g., within 10m). In this situation, due to the inherent size of the light spot, adjacent signal points on the line will overlap, resulting in convolution. This convolution makes the light intensity of the received signal points on the line more uniform. Therefore, in reality, the non-uniformity of a line received at close range is much lower than that of a line projected at infinity (e.g., at a distance of less than 10m). Figure 9 The simulation results shown demonstrate non-uniformity. For example, as... Figures 5 to 9 In the embodiment shown, in the case of close-range reception, the field of view θb of the transition region is 5.7°, and the non-uniformity of the intermediate region is less than 30%.

[0146] In this invention, the method for calculating light intensity non-uniformity is as follows:

[0147] (Maximum light intensity - Minimum light intensity) / (Maximum light intensity + Minimum light intensity).

[0148] The diffractive optical element 30 can also be configured such that the intensity distribution of the projected light from the linear projection pattern 65 satisfies a preset intensity distribution curve. Besides the uniform distribution described above, for example, the intensity distribution of the projected light from the linear projection pattern 65 can be such that the intensity distribution in the middle region is 1 / (cosα). a The normalized intensity distribution is given by α, where a is a real number in the range (0, 1.5) and α is the diffraction angle corresponding to each point on the line.

[0149] In this application, preferably, the number of laser sources 20 in each row of laser sources 21 is 7 to 25. Preferably, the multiple laser sources 20 in each row are distributed at equal intervals (or substantially equal intervals). Preferably, the distance D between two adjacent laser sources 20 in each row is 20 μm to 40 μm. Preferably, the total width L of the distribution of multiple laser sources 20 in each row is 150 μm to 600 μm. Preferably, the field of view θs of the linear projection pattern 60 projected by the laser emitted by a single laser source 20 is 40° to 130°. Preferably, the diffractive optical element 30 is parallel to the substrate assembly 10, such that the distance between the multiple laser sources 20 and the diffractive optical element 30 is equal. Preferably, the air gap G between the laser source 20 and the diffractive optical element 30 is 2 mm to 5.5 mm. Preferably, the diffractive optical element 30 includes a micro / nano structure with 2 steps, 4 steps, or 8 steps. Preferably, the laser source 20 is a vertical-cavity surface-emitting laser (VCSEL). Of course, the laser source 20 can also be, for example, an LED laser source or an edge-emitting laser (EEL).

[0150] like Figure 10 As shown, in one specific embodiment, the linear laser projector 100 includes a row of laser light sources 21, comprising eight laser light sources 20. These eight laser light sources 20 are evenly spaced, with a total distribution width L of 175 μm (equivalent to a distance d of 25 μm between two adjacent laser light sources 20). The distance between two adjacent rows of laser light sources is 250 μm. The air gap G between the laser light sources 20 and the diffractive optical element 30 is 2.5 mm. The laser wavelength is 940 nm. The diffractive optical element 30 is configured such that parameter M is 3. Wherein, as... Figure 11 As shown, the field of view θs along the X direction of the linear projection pattern 60 projected by the laser emitted by a single laser source 20 is 120°, and the field of view along the Y direction is 22.5° (see...). Figure 11 The dashed frame and the linear projection pattern 60 located in the middle). (e.g.) Figure 12 As shown, the field of view of the three linear projection patterns 65 projected by all eight laser light sources 20 is greater than 120° in the X direction and 22.5° in the Y direction (see...). Figure 12 (middle dashed box).

[0151] like Figure 1 As shown, when N is greater than 1, preferably, a plurality of laser light sources 20 are arranged in N rows at equal or substantially equal intervals along a direction Y perpendicular to the set straight line direction X on the substrate assembly 10. For example, a plurality of laser light sources 20 are arranged in N rows at equal intervals h in the Y direction.

[0152] The diffractive optical element 30 is configured such that, when N is greater than 1, the M linear projection patterns 65 projected by any row of laser light sources 21 in the N rows are adjacent along the direction Y perpendicular to the set straight line direction X. That is, the M linear projection patterns 65 projected by any row of laser light sources 21 in the N rows are not intersected with the M linear projection patterns 65 projected by any other row of laser light sources 21 in the N rows along the direction Y perpendicular to the set straight line direction X. For example, the qth linear projection pattern 65 projected by the p-th row laser light source 21 is denoted as linear pq (p and q are integers, 1≤p≤N, 1≤q≤M). The linear laser projector 100 is constructed such that the N×M linear projection patterns 65 have the following arrangement: the M linear patterns pq with the same p value are adjacent along the direction Y perpendicular to the set straight line direction X; the p values ​​of the N linear patterns pq with the same q value are arranged in reverse order of the row number of the laser light source along the direction Y perpendicular to the set straight line direction X.

[0153] like Figure 1 As shown, the linear laser projector 100 includes four (N=4) rows of laser light sources 21A (row number 1), 21B (row number 2), 21C (row number 3), and 21D (row number 4). Each row of laser light sources 21 projects two (M=2) linear projection patterns 65. Specifically, row laser light source 21A projects linear projection patterns 65A1 (line 11) and 65A2 (line 12), row laser light source 21B projects linear projection patterns 65B1 (line 21) and 65B2 (line 22), row laser light source 21C projects linear projection patterns 65C1 (line 31) and 65C2 (line 32), and row laser light source 21D projects linear projection patterns 65D1 (line 41) and 65D2 (line 42). On the projection screen 50, the eight linear projection patterns 65 are arranged in the Y-direction as follows: linear 41, linear 42, linear 31, linear 32, linear 21, linear 22, linear 11, and linear 12. It can be seen that these eight linear projection patterns 65 satisfy the following conditions: two linear patterns pq with the same p value are adjacent along the Y-direction; and the p values ​​of four linear patterns pq with the same q value are arranged in reverse order along the Y-direction according to the row number of the corresponding laser light source 20.

[0154] Preferably, the linear laser projector 100 is configured such that N×M linear projection patterns 65 are arranged at equal intervals (or substantially equal intervals) along the Y direction. To achieve the equal interval arrangement of N×M linear projection patterns 65 and the aforementioned non-intersecting arrangement effect, multiple laser light sources 20 are arranged in N rows at equal intervals h in the Y direction, and the diffractive optical elements 30 are parallel to the substrate assembly 10. Meanwhile, the structural parameters of the laser projector 100 satisfy the following formula (1):

[0155]

[0156] Where D is the minimum period of the diffractive optical element 30 along the direction Y perpendicular to the set straight line X, λ is the wavelength of the laser (e.g., 840-950nm, such as 940nm, 850nm), h is the distance between two adjacent rows of the laser source 20 along the direction Y perpendicular to the set straight line X, and G is the air gap between the laser source 20 and the diffractive optical element 30.

[0157] In this implementation, the field of view θv of two adjacent linear projection patterns 65 projected by the same row of laser light sources 21 along the Y direction is calculated according to the following formula (1-1), the field of view θvm of M linear projection patterns 65 projected by the same row of laser light sources 21 along the Y direction is calculated according to the following formula (1-2), and the field of view θvn of N×M linear projection patterns 65 projected by all laser light sources 20 along the Y direction is calculated according to the following formula (1-3).

[0158] θv=2arctan(h / (2MG)) (1-1)

[0159] θvm=θv×(M-1) (1-2)

[0160] θvn =θv×(N×M-1) (1-3)

[0161] like Figure 13 As shown, in one specific embodiment, the linear laser projector 100 includes four rows of laser light sources. Each row of laser light sources 21 includes eight laser light sources 20, which are equally spaced, with a total distribution width L of 175 μm (equivalent to a distance d of 25 μm between two adjacent laser light sources 20 in each row). The distance between two adjacent rows of laser light sources is 250 μm. The air gap G between the laser light sources 20 and the diffractive optical element 30 is 2.5 mm. The laser wavelength is 940 nm. The diffractive optical element 30 is constructed such that parameter M is 2, and the eight linear projection patterns 65 are arranged according to the aforementioned non-intersecting pattern. Wherein, as... Figure 14As shown, the field of view θs along the X direction of the two linear projection patterns 60 projected by the laser emitted by a single laser source 20 is 120°, and the field of view θv and θvm along the Y direction are 2.86° (see [reference]). Figure 13 (Middle dashed box). For example Figure 15 As shown, the field of view 65 projected by all 4 rows of 32 laser light sources 20, forming 8 linear projection patterns, has a field of view θvn greater than 120° along the X direction and a field of view θvn of 20.05° along the Y direction (see [reference]). Figure 15 (middle dashed box).

[0162] Understandable. Figure 1 The diffractive optical element 30 of the linear laser projector 100 shown has a collimation function. For example... Figure 16 As shown, when the diffractive optical element 30 does not have a collimation function, the linear laser projector 100 also includes a collimating lens 40. The collimating lens 40 is located between the laser source 20 and the diffractive optical element 30, and is used to collimate the laser beam emitted by the laser source 20. Figure 16 In the illustrated embodiment, θb = arctg(L / f), where f is the focal length of the collimating lens 40. Preferably, the focal length f of the collimating lens 40 is 2mm to 5.5mm. When the linear laser projector 100 includes the collimating lens 40, if it is to project an image as shown... Figure 1 The N×M linear projection pattern 65 shown is uniformly distributed along the Y direction and has no intersections. Then, multiple laser light sources 20 are arranged in N rows at equal intervals along the Y direction perpendicular to the set straight line direction X on the substrate assembly 10. The structural parameters of the laser projector 100 satisfy the following formula (2):

[0163]

[0164] Where D is the minimum period of the diffractive optical element 30 along the direction Y perpendicular to the set straight line X, λ is the wavelength of the laser, h is the distance between two adjacent rows of the laser source 20 along the direction Y perpendicular to the set straight line X, and f is the focal length of the collimating lens 40. In this embodiment, the field of view θv along the Y direction of two adjacent linear projection patterns 65 projected by the same row of laser sources 21 is calculated according to the following formula (2-1), the field of view θvm along the Y direction of M linear projection patterns 65 projected by the same row of laser sources 21 is calculated according to the following formula (2-2), and the field of view θvn along the Y direction of N×M linear projection patterns 65 projected by all laser sources 20 is calculated according to the following formula (2-3).

[0165] θv=2arctan(h / (2Mf)) (2-1)

[0166] θvm=θv×(M-1) (2-2)

[0167] θvn =θv×(N×M-1) (2-3)

[0168] Figure 17 A line-shaped laser projector 200 according to a second preferred embodiment of this application is shown. Figure 16 In the illustrated embodiment, the linear laser projector 200 includes a substrate assembly 10, a plurality of laser light sources 20, and a diffractive optical element 230. The plurality of laser light sources 20 are disposed on the substrate assembly 10 and are used to emit laser light. The plurality of laser light sources 20 are arranged in N rows (N is a positive integer, N=4 in the illustrated embodiment) along a direction Y perpendicular to a predetermined straight line X, wherein each row of laser light sources 21 includes a plurality of laser light sources 20 arranged along the predetermined straight line X. The diffractive optical element 230 is used to diffuse the laser light emitted by the plurality of laser light sources 20 along the predetermined straight line X to form N×M (M is a positive integer greater than 1, M=2 in the illustrated embodiment) linear projection patterns 65 extending along the predetermined straight line X, wherein the N×M linear projection patterns 65 are spaced apart along a direction Y perpendicular to the predetermined straight line X.

[0169] and Figure 1 The difference between the embodiments shown is that, in Figure 17 In the illustrated embodiment, the arrangement of the N×M linear projection patterns 65 is staggered relative to the N rows of laser light sources 21. That is, the diffractive optical element 30 is configured such that, when N is greater than 1, the M linear projection patterns 65 projected by at least one row of laser light sources 21 and the M linear projection patterns 65 projected by at least another row of laser light sources 21 are staggered along a direction Y perpendicular to the set straight line direction X. For example, the qth linear projection pattern 65 projected by the p-th row laser light source 21 is denoted as linear pq (p and q are integers, 1≤p≤N, 1≤q≤M). The linear laser projector 100 is constructed such that the N×M linear projection patterns 65 have the following relationship: N linear pq with the same q value are adjacent along the direction Y perpendicular to the set straight line direction X; the p values ​​of the N linear pq with the same q value are arranged in reverse order of the row number of the laser light source 20 along the direction Y perpendicular to the set straight line direction X.

[0170] like Figure 17As shown, the linear laser projector 200 includes four (N=4) rows of laser light sources 21A (row number 1), 21B (row number 2), 21C (row number 3), and 21D (row number 4). Each row of laser light sources 21 projects two (M=2) linear projection patterns 65. Specifically, row laser light source 21A projects linear projection patterns 65A1 (line 11) and 65A2 (line 12), row laser light source 21B projects linear projection patterns 65B1 (line 21) and 65B2 (line 22), row laser light source 21C projects linear projection patterns 65C1 (line 31) and 65C2 (line 32), and row laser light source 21D projects linear projection patterns 65D1 (line 41) and 65D2 (line 42). On the projection screen 50, the eight linear projection patterns 65 are arranged in the Y-direction as follows: linear 41, linear 31, linear 21, linear 11, linear 42, linear 32, linear 22, and linear 12. It can be seen that these eight linear projection patterns 65 satisfy the following conditions: four linear patterns pq with the same q value are adjacent along the Y-direction; and the p values ​​of the four linear patterns pq with the same q value are arranged in reverse order along the Y-direction according to the row number of the corresponding laser light source 20.

[0171] Preferably, the linear laser projector 200 is configured such that N×M linear projection patterns 65 are arranged at equal intervals (or substantially equal intervals) along the Y direction. To achieve the equal interval arrangement of N×M linear projection patterns 65 and the aforementioned staggered arrangement effect, multiple laser light sources 20 are arranged in N rows at equal intervals h along the Y direction, and the diffractive optical element 230 is parallel to the substrate assembly 10. Meanwhile, the structural parameters of the laser projector 100 satisfy the following formula (3):

[0172]

[0173] Where D is the minimum period of the diffractive optical element 230 along the direction Y perpendicular to the set straight line X, λ is the wavelength of the laser, h is the distance between two adjacent rows of the laser source 20 along the direction Y perpendicular to the set straight line X, and G is the air gap between the laser source 20 and the diffractive optical element 230.

[0174] In this implementation, the field of view θv of two adjacent linear projection patterns 65 projected by the same row of laser light sources 21 along the Y direction is calculated according to the following formula (3-1), the field of view θvm of M linear projection patterns 65 projected by the same row of laser light sources 21 along the Y direction is calculated according to the following formula (3-2), and the field of view θvn of N×M linear projection patterns 65 projected by all laser light sources 20 along the Y direction is calculated according to the following formula (3-3).

[0175] θv=2arctan(N·h / (2G)) (3-1)

[0176] θvm=θv×(M-1) (3-2)

[0177] θvn =θv×(N×M-1) / N (3-3)

[0178] Understandable, Figure 17 In the illustrated embodiment, the diffractive optical element 230 has a collimation function. When the diffractive optical element 230 does not have a collimation function, it is similar to... Figure 16 Similar to the illustrated embodiment, the linear laser projector 200 also includes a collimating lens 40. The collimating lens 40 is located between the laser source 20 and the diffractive optical element 230, and is used to collimate the laser beam emitted by the laser source 20. In this embodiment, θb = arctg(L / f), where f is the focal length of the collimating lens 40. Preferably, the focal length f of the collimating lens 40 is 2 mm to 5.5 mm. When the linear laser projector 200 includes the collimating lens 40, to project an image as shown... Figure 17 The N×M interlaced linear projection pattern 65 uniformly distributed along the Y direction shown means that multiple laser light sources 20 are arranged in N rows at equal intervals along the Y direction perpendicular to the set straight line direction X on the substrate assembly 10. The structural parameters of the laser projector 100 satisfy the following formula (4):

[0179]

[0180] Where D is the minimum period of the diffractive optical element 230 along the direction perpendicular to the set straight line, λ is the wavelength of the laser, h is the distance between two adjacent rows of the laser source 20 along the direction Y perpendicular to the set straight line X, and f is the focal length of the collimating lens 40.

[0181] In this implementation, the field of view θv of two adjacent linear projection patterns 65 projected by the same row of laser light sources 21 along the Y direction is calculated according to the following formula (4-1), the field of view θvm of M linear projection patterns 65 projected by the same row of laser light sources 21 along the Y direction is calculated according to the following formula (4-2), and the field of view θvn of N×M linear projection patterns 65 projected by all laser light sources 20 along the Y direction is calculated according to the following formula (4-3).

[0182] θv=2arctan(N·h / (2f)) (4-1)

[0183] θvm=θv×(M-1) (4-2)

[0184] θvn =θv×(N×M-1) / N (4-3)

[0185] When N=1, the laser projector 100 projects M linear projection patterns 65. The structural parameters of the laser projector 100 satisfy the following formula (5):

[0186]

[0187] Where D is the minimum period of the diffractive optical element 30 along the direction Y perpendicular to the set straight line X, λ is the wavelength of the laser, and θv is the field of view angle of two adjacent lines of the M linear projection patterns 65 along the direction Y perpendicular to the set straight line X. In this embodiment, the field of view angle θvm of the M linear projection patterns 65 projected by the same row of laser light sources 21 along the Y direction is M times the field of view angle θvn of the N×M linear projection patterns 65 projected by all laser light sources 20.

[0188] In practice, users usually determine the field of view angles θvn, θvm, θv, etc. according to specific needs, and then determine the appropriate M and N values ​​by combining the spacing of the laser source along the X direction, the spacing h along the Y direction, and the focal length f of the collimating lens 40 or the air gap G. Then, the structural parameters of the diffractive optical elements are derived by using the field of view calculation formulas related to formulas (1)-(5).

[0189] like Figure 18 As shown, in one specific embodiment, the linear laser projector 200 includes four rows of laser light sources. Each row of laser light sources 21 includes eight laser light sources 20, which are equally spaced, with a total distribution width L of 175 μm (equivalent to a distance d of 25 μm between two adjacent laser light sources 20 in each row). The distance between two adjacent rows of laser light sources is 250 μm. The air gap G between the laser light sources 20 and the diffractive optical element 30 is 2.5 mm. The laser wavelength is 940 nm. The diffractive optical element 30 is constructed such that parameter M is 2, and the eight linear projection patterns 65 are arranged according to the aforementioned staggered pattern. Wherein, as... Figure 19 As shown, the field of view θs along the X direction of the two linear projection patterns 60 projected by the laser emitted by a single laser source 20 is 120°, and the field of view θv and θvm along the Y direction are 22.5° (see [reference]). Figure 19 (Middle dashed box). For example Figure 20 As shown, the field of view 65 projected by all 4 rows of 32 laser light sources 20, which project 8 linear projection patterns 65, has a field of view θvn greater than 120° along the X direction and a field of view θvn of 40° along the Y direction (see [reference]). Figure 20 (middle dashed box).

[0190] Compared to Figure 1 The non-interlaced implementation shown, Figure 17The staggered implementation shown makes it easier to obtain a larger field of view in the Y direction.

[0191] exist Figure 18 In the embodiment shown, the light intensity (energy) distribution of the two linear projection patterns 60 projected by a single laser light source 20 is as follows: Figure 21 and Figure 22 As shown, the light intensity (energy) distribution of the two linear projection patterns 65 projected by a row of laser light sources 21 corresponding to the single laser light source 20 is as follows: Figure 23 and Figure 24 As shown. By Figure 21 and Figure 23 Comparison, will Figure 22 and Figure 24 Comparison shows that when the projected light from eight laser sources 20 is superimposed, the field of view of the superimposed linear projection pattern 65 in the X direction increases, and the uniformity of light intensity after multi-point superposition is significantly improved. From Figures 25 to 28 It can also be seen that the field of view of the superimposed linear projection pattern 65 in the X direction is increased, and the uniformity of light intensity after multi-point superposition is significantly improved.

[0192] A second aspect of this application provides a camera assembly. In a preferred embodiment, the camera assembly includes the aforementioned linear laser projector 100, image acquisition unit, and processor. The image acquisition unit is used to acquire a laser image formed by the pattern projected by the linear laser projector 100; the processor is used to process the laser image to obtain a depth image. The camera assembly according to this application can easily project a linear line with a light intensity distribution that meets preset light intensity distribution requirements (e.g., uniform or non-uniform) according to application needs, and can capture and process the laser image formed by the linear line.

[0193] A third aspect of this application provides an electronic device. In a preferred embodiment, the electronic device includes a housing and the aforementioned camera assembly. The camera assembly is disposed to and exposed from the housing to obtain a depth image. The electronic device may be, for example, a mobile phone, a wristband, a watch, a tablet computer, smart glasses, a smart helmet, or a motion-sensing gaming device. The electronic device according to this application can easily project a line with a light intensity distribution that meets preset light intensity distribution requirements (e.g., uniform or non-uniform) according to application needs, and can capture and process the laser image formed by the line.

[0194] Unless otherwise defined, the technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used herein is for descriptive purposes only and is not intended to limit the scope of this application. Features described in one embodiment may be applied, alone or in combination with other features, to another embodiment, unless that feature is not applicable in that other embodiment or is otherwise stated.

[0195] This application has been described through the above embodiments. However, it should be understood that the above embodiments are for illustrative purposes only and are not intended to limit this application to the described embodiments. Furthermore, those skilled in the art will understand that this application is not limited to the above embodiments, and many more variations and modifications can be made based on the teachings of this application, all of which fall within the scope of protection claimed in this application.

Claims

1. A linear laser projector, characterized in that, include: Substrate assembly; Multiple laser light sources are disposed on the substrate assembly for emitting laser light. The multiple laser light sources are arranged in N rows along a direction perpendicular to a predetermined straight line, wherein each row includes multiple laser light sources arranged along the predetermined straight line. A diffractive optical element is used to diffuse the laser light emitted by the plurality of laser light sources along the predetermined straight line direction, such that each row of laser light sources projects M linear projection patterns extending along the predetermined straight line direction, forming N×M linear projection patterns extending along the predetermined straight line direction, where N is a positive integer greater than 1 and M is a positive integer greater than 1. The N×M linear projection patterns are arranged at intervals along a direction perpendicular to the predetermined straight line direction. In this configuration, the M linear projection patterns projected by at least one row of the N rows of laser light sources are staggered with the M linear projection patterns projected by at least another row of the N rows of laser light sources in a direction perpendicular to the predetermined straight line. Here, the q-th linear projection pattern projected by the laser light source in the p-th row is denoted as line pq, where p and q are integers, 1≤p≤N, 1≤q≤M. The linear laser projector is configured such that the N×M linear projection patterns have the following relationship: N lines pq with the same q value are adjacent to each other in a direction perpendicular to the defined straight line. The p values ​​of the N lines pq with the same q value are arranged in reverse order of the row number of the laser source along a direction perpendicular to the set straight line.

2. The linear laser projector according to claim 1, characterized in that, The plurality of laser light sources are arranged in N rows at equal intervals on the substrate assembly along a direction perpendicular to the predetermined straight line.

3. The linear laser projector according to claim 1, characterized in that, In each row of the laser light source: The number of laser sources is 7 to 25, and / or The multiple laser light sources are distributed at equal intervals.

4. The linear laser projector according to claim 1, characterized in that, In each row of the laser light source: The distance between two adjacent laser sources is 20 μm to 40 μm, and / or The total width of the distribution of the plurality of laser sources is 150μm to 600μm.

5. The linear laser projector according to claim 1, characterized in that, The field of view of the linear projection pattern projected by the laser emitted by a single laser source is 40° to 130° along the set straight line direction.

6. The linear laser projector according to claim 1, characterized in that, The diffractive optical element is parallel to the substrate assembly, and the air gap between the laser source and the diffractive optical element is 2 mm to 5.5 mm.

7. The linear laser projector according to claim 1, characterized in that, It also includes a collimating lens, which is disposed between the laser source and the diffractive optical element.

8. The linear laser projector according to claim 7, characterized in that, The focal length of the collimating lens is 2mm to 5.5mm.

9. The linear laser projector according to claim 1, characterized in that, The laser source is a vertical cavity surface-emitting laser element.

10. The linear laser projector according to claim 1, characterized in that, The diffractive optical element comprises a micro / nano structure with 2, 4, or 8 steps.

11. The linear laser projector according to claim 1, characterized in that, The diffractive optical element is configured such that the intensity distribution of the projected light of each of the linear projection patterns satisfies a preset intensity distribution curve.

12. The linear laser projector according to claim 11, characterized in that, Each of the linear projection patterns includes transition regions at both ends and a middle region located between two of the transition regions. The linear laser projector is configured such that the intensity of the projected light in the middle region is proportional to 1 / (cosα). a The normalized intensity distribution, where a is a real number in the range of (0, 1.5), and α is the diffraction angle of each point on the linear projection pattern.

13. The linear laser projector according to any one of claims 1 to 12, characterized in that, The plurality of laser light sources are arranged in N rows at equal intervals on the substrate assembly along a direction perpendicular to the predetermined straight line, and the diffractive optical elements are parallel to the substrate assembly. The structural parameters of the laser projector satisfy the following formula: Where D is the minimum period of the diffractive optical element along the direction perpendicular to the set straight line, λ is the wavelength of the laser, h is the distance between two adjacent rows of the laser source along the direction perpendicular to the set straight line, and G is the air gap between the laser source and the diffractive optical element.

14. The linear laser projector according to any one of claims 1 to 12, characterized in that, The plurality of laser light sources are arranged in N rows at equal intervals on the substrate assembly along a direction perpendicular to the predetermined straight line. The linear laser projector further includes a collimating lens disposed between the laser light sources and the diffractive optical element. The structural parameters of the laser projector satisfy the following formula: Wherein, D is the minimum period of the diffractive optical element along the direction perpendicular to the set straight line, λ is the wavelength of the laser, h is the distance between two adjacent rows of the laser source along the direction perpendicular to the set straight line, and f is the focal length of the collimating lens.

15. A camera assembly, characterized in that, include: Linear laser projector according to any one of claims 1-14; An image acquisition device is used to acquire a laser image formed by the pattern projected by the linear laser projector; and A processor for processing the laser image to obtain a depth image.

16. An electronic device, characterized in that, include: shell; and The camera assembly of claim 15 is disposed to and exposed from the housing to obtain a depth image.

Images