CN114002698A - Depth camera, method for manufacturing light emitting module and terminal - Google Patents

Depth camera, method for manufacturing light emitting module and terminal Download PDF

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Publication number
CN114002698A
CN114002698A CN202111261453.6A CN202111261453A CN114002698A CN 114002698 A CN114002698 A CN 114002698A CN 202111261453 A CN202111261453 A CN 202111261453A CN 114002698 A CN114002698 A CN 114002698A
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China
Prior art keywords
pattern
light emitting
light
optical element
zero
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CN202111261453.6A
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Chinese (zh)
Inventor
刘海亮
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Guangdong Oppo Mobile Telecommunications Corp Ltd
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Guangdong Oppo Mobile Telecommunications Corp Ltd
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Priority to CN202111261453.6A priority Critical patent/CN114002698A/en
Publication of CN114002698A publication Critical patent/CN114002698A/en
Priority to PCT/CN2022/120965 priority patent/WO2023071650A1/en
Pending legal-status Critical Current

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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S17/00—Systems using the reflection or reradiation of electromagnetic waves other than radio waves, e.g. lidar systems
    • G01S17/02—Systems using the reflection of electromagnetic waves other than radio waves
    • G01S17/06—Systems determining position data of a target
    • G01S17/46—Indirect determination of position data
    • G01S17/48—Active triangulation systems, i.e. using the transmission and reflection of electromagnetic waves other than radio waves
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
    • G01S7/48—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S17/00
    • G01S7/491—Details of non-pulse systems
    • G01S7/4911—Transmitters
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
    • G01S7/48—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S17/00
    • G01S7/491—Details of non-pulse systems
    • G01S7/4912—Receivers
    • G01S7/4915—Time delay measurement, e.g. operational details for pixel components; Phase measurement

Abstract

The application discloses a depth camera, a method for manufacturing a light emitting module and a terminal. The depth camera comprises a light emitting module and a light receiving module, wherein the light emitting module comprises a light source and a diffractive optical element. The light source is used for emitting light beams to form a planar pattern. The integrated microstructure on the diffractive optical element can collimate and replicate the planar pattern to emit a speckle pattern; the zero order region in the speckle pattern and a plurality of first order regions surrounding the zero order region satisfy: gapx＝q△x，0.8<q<1.5；gapy＝p△y，0.8<p<1.5. Wherein, gapxA first distance, gap, between the first order region and the zero order region in a first directionyIs the second distance between the first order region and the zero order region in the second direction, and Δ x is the first distance between two adjacent speckles arranged in the same row in the zero order region in the first directionAnd Δ y is a second spacing in the second direction of speckles in two adjacent rows in the zero-order region.

Description

Depth camera, method for manufacturing light emitting module and terminal
Technical Field
The present application relates to the field of ranging technologies, and more particularly, to a depth camera, a method of manufacturing a light emission module, and a terminal.
Background
The light emitting module in a depth camera generally employs a combination of "light source + lens group + diffractive optical element", wherein the lens group is used for collimating a plane pattern emitted by the light source, and the diffractive optical element is used for duplicating and emitting the duplicated plane pattern. The light emitting module with the structure has good optical effects (including but not limited to efficiency, uniformity and light spot quality), but the scheme has larger volume and higher overall cost.
Disclosure of Invention
The embodiment of the application provides a depth camera, a method for manufacturing a light emitting module and a terminal.
The embodiment of the application provides a depth camera. The depth camera comprises a light emitting module and a light receiving module. The light emitting module includes a light source and a diffractive optical element. The light source includes a plurality of light emitting elements and emits light beams to form a planar pattern. The diffractive optical element is provided with an integrated microstructure which can collimate the planar pattern and replicate the planar pattern to emit a speckle pattern; the speckle pattern comprises a zero-order region and a plurality of first-order regions surrounding the zero-order region, and the zero-order region and the first-order regions meet the following conditions: gapx＝q△x，0.8<q<1.5；gapy＝p△y，0.8<p<1.5. Wherein, gapxA first distance, gap, in a first direction between the first order region and the zero order regionyThe second distance between the first-order region and the zero-order region in the second direction is represented by Δ x, which is a first distance between two adjacent speckles arranged in the same row in the zero-order region in the first direction, and Δ y, which is a second distance between two adjacent rows of speckles in the zero-order region in the second direction. The light receiving module is used for receiving at least part of the light reflected by the object and converting the light into an electric signal.
The embodiment of the present application further provides a method for manufacturing the light emitting module according to the above embodiment. The manufacturing method comprises the following steps: acquiring a first pattern formed by emission of a reference module; the reference module comprises a light-emitting component, a collimating lens group and a first optical element, wherein the light-emitting component can emit a light beam to form a second pattern, the collimating lens group is used for collimating the second pattern, the first optical element is used for copying the second pattern to emit the first pattern, the first pattern is a planar pattern, and the second pattern is a speckle pattern; designing a diffractive optical element of the light emitting module according to the first pattern and the second pattern so that the second pattern can be emitted out of the first pattern after passing through the diffractive optical element; designing a light source of the light emitting module according to the light emitting component so that the light source emits a light beam capable of forming the second image; and assembling the diffractive optical element in the light-emitting direction of the light source to obtain the light-emitting module.
The embodiment of the application also provides a terminal. The terminal includes a housing and a depth camera. The depth camera is coupled to the housing. The depth camera comprises a light emitting module and a light receiving module. The light emitting module includes a light source and a diffractive optical element. The light source includes a plurality of light emitting elements and emits light beams to form a planar pattern. The diffractive optical element is provided with an integrated microstructure which can collimate the planar pattern and replicate the planar pattern to emit a speckle pattern; the speckle pattern comprises a zero-order region and a plurality of first-order regions surrounding the zero-order region, and the zero-order region and the first-order regions meet the following conditions: gapx＝q△x，0.8<q<1.5；gapy＝p△y，0.8<p<1.5. Wherein, gapxA first distance, gap, in a first direction between the first order region and the zero order regionyThe second distance between the first-order region and the zero-order region in the second direction is represented by Δ x, which is a first distance between two adjacent speckles arranged in the same row in the zero-order region in the first direction, and Δ y, which is a second distance between two adjacent rows of speckles in the zero-order region in the second direction. The light receiving module is used for receiving at least part of the light reflected by the object and converting the light into an electric signal.
The depth camera, the method for manufacturing the light emitting module and the terminal provided by the application can collimate the planar pattern through the integrated microstructure on the diffractive optical element and duplicate the planar pattern to emit the speckle pattern, and the zero-order area and the first-order area in the formed speckle pattern can also meet the gap requirementx＝q△x，0.8<q<1.5; and gapy＝p△y，0.8<p<1.5. On the one hand, compare in adopting different optical element to realize collimation respectively and duplicate the function, the light emission module of this application can also dwindle the light emission module under the prerequisite that does not influence the optical effect who throws speckle imageThe size of the light emitting module is reduced, and the manufacturing cost of the light emitting module is reduced, so that the size and the cost of the depth camera are reduced; on the other hand, the gap can be satisfied because the zero-order region and the first-order region in the speckle patternx＝q△x，0.8<q<1.5; and gapy＝p△y，0.8<p<1.5, this can satisfy the requirement of follow-up software calculation, can seek zero order district and first order district in the speckle pattern fast and accurately, is favorable to promoting efficiency and the rate of accuracy that the depth information acquireed.
Additional aspects and advantages of embodiments of the present application 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 embodiments of the present application.
Drawings
The above and/or additional aspects and advantages of the present application 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 block diagram of a depth camera in some embodiments of the present application;
FIG. 2 is a schematic diagram of a light emitting module according to some embodiments of the present disclosure;
FIGS. 3 and 4 are schematic illustrations of speckle images in certain embodiments of the present application;
FIG. 5 is a schematic diagram of a reference module in some embodiments of the present application;
FIGS. 6(a) and 6(b) are schematic illustrations of planar images in some embodiments of the present application;
FIGS. 7-9 are schematic diagrams of light sources in certain embodiments of the present application;
10-12 are schematic diagrams of speckle images in certain embodiments of the present application;
FIG. 13 is a schematic structural view of a first microstructure in certain embodiments of the present application;
FIG. 14 is a schematic structural view of a second microstructure in certain embodiments of the present application;
FIG. 15 is a schematic representation of the principle of integrated microstructures formed in certain embodiments of the present application;
fig. 16 to 18 are schematic structural views of a light emitting module according to some embodiments of the present disclosure;
fig. 19 and 20 are schematic views of a light emitting module reproducing a planar pattern according to some embodiments of the present disclosure;
FIG. 21 is a block diagram of a terminal in some embodiments of the present application;
fig. 22 is a flow chart of a method of fabricating a light emitting module according to some embodiments of the present disclosure.
Detailed Description
Embodiments of the present application will be further described below with reference to the accompanying drawings. The same or similar reference numbers in the drawings identify the same or similar elements or elements having the same or similar functionality throughout.
In addition, the embodiments of the present application described below in conjunction with the accompanying drawings are exemplary and are only for the purpose of explaining the embodiments of the present application, and are not to be construed as limiting the present application.
In this application, unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through intervening media. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.
The light emitting module in a depth camera generally employs a combination of "light source + lens group + diffractive optical element", wherein the lens group is used for collimating a plane pattern emitted by the light source, and the diffractive optical element is used for duplicating and emitting the duplicated plane pattern. The light emitting module with the structure has good optical effects (including but not limited to efficiency, uniformity and light spot quality), but the scheme has larger volume and higher overall cost.
To solve the above problem, please refer to fig. 1, 2 to 4 andfig. 7 is a block diagram illustrating a depth camera 100 according to an embodiment of the present disclosure, in which the depth camera 100 includes a light emitting module 10 and a light receiving module 20. The light emitting module 10. The light emitting module 10 includes a light source 11 and a diffractive optical element 12. The light source 11 includes a plurality of light emitting elements 111 and serves to emit light beams to form a planar pattern. The diffractive optical element 12 is provided with an integrated microstructure 121, the integrated microstructure 121 being capable of collimating a planar pattern and replicating the planar pattern to emit a speckle pattern. The speckle pattern comprises a zero-order area a and a plurality of first-order areas b surrounding the zero-order area a, and the zero-order area a and the first-order areas b meet the following conditions: gapx＝q△x，0.8<q<1.5; and gapy＝p△y，0.8<p<1.5. Wherein, gapxA first distance, gap, between the first order region b and the zero order region a in a first direction D1yThe second distance between the first-order region b and the zero-order region a in the second direction D2, Δ x is a first distance between two adjacent speckles arranged in the same row in the zero-order region a in the first direction D1, and Δ y is a second distance between two adjacent speckles in the zero-order region a in the second direction D2. The light receiving module 20 is used for receiving at least part of the light reflected by the object and converting the light into an electrical signal.
The light emitting module 10 in the depth camera 100 of the present application collimates the planar pattern through the integrated microstructure 121 on the diffractive optical element 12 and replicates the planar pattern to emit the speckle pattern, and the zero-order region a and the first-order region b in the formed speckle pattern can also satisfy the gapx＝q△x，0.8<q<1.5; and gapy＝p△y，0.8<p<1.5. On one hand, compared with the method that different optical elements are adopted to respectively realize the functions of collimation and replication, the light emitting module 10 can reduce the volume of the light emitting module 10 and reduce the manufacturing cost of the light emitting module 10 on the premise of not influencing the optical effect of projecting speckle images; on the other hand, when the first distance gap between the zero-order region a and the first-order region b in the speckle patternxOr a second distance gapyToo large, it takes time to find the first-level region b in the speckle pattern in the subsequent software calculation process, and the efficiency is reduced; a first distance gap between the zero-level region a and the first-level region b in the spot patternxOr a second distance gapyToo small results in that the zero-level region a and the first-level region b cannot be well distinguished in the subsequent software calculation process, thereby resulting in low calculation accuracy of the depth information. The zero-order area a and the first-order area b in the speckle pattern formed in the application can also satisfy gapx＝q△x，0.8<q<1.5; and gapy＝p△y，0.8<p<1.5, this can satisfy the requirement of follow-up software calculation, can seek zero order area a and first order district b in the speckle pattern fast and accurately, is favorable to promoting efficiency and the rate of accuracy that the depth information acquireed.
It should be noted that the light beams emitted by the plurality of light emitting elements 111 form a planar pattern, and the planar pattern is replicated after passing through the diffractive optical element 12 to be emitted to form a speckle pattern, that is, the speckle pattern is formed by a plurality of planar pattern sets. The speckle pattern includes a plurality of speckles therein. The depth camera 100 may be a Time of flight (TOF) -based depth camera, that is, the depth camera 100 may calculate depth information of an object according to a Time difference between the light beam emitted by the light source 11 and the speckle received by the light receiving module 20.
Referring to fig. 7, in some embodiments, the light emitting elements 111 of the light source 11 are regularly arranged. On one hand, since the plurality of light emitting elements 111 are regularly arranged, compared with the plurality of light emitting elements 111 which are arranged in a mess, the volume of the light source 11 is reduced; on the other hand, the planar pattern comprises a plurality of light-emitting points formed by emitting light beams by the light-emitting elements 111, and the plurality of light-emitting elements 111 are regularly arranged, and the planar pattern is copied to form a speckle pattern, so that the plurality of speckles in the speckle pattern are not overlapped with each other, and the subsequent finding of the corresponding speckles is facilitated to obtain the depth information. It should be noted that the light source 11 includes a plurality of rows of light emitting elements 111, and each row of light emitting elements 111 includes a plurality of light emitting elements 111. In one example, if the pitches between the rows are the same, the light emitting elements 111 in the light source 11 may be considered to be regularly arranged; on the contrary, if the intervals between the rows are different, or there is no correlation between the rows (the correlation includes, but is not limited to, a direct ratio, an inverse ratio, an increasing and a decreasing, and the differences are not described in detail below), it may be considered that the light emitting elements 111 in the light source 11 are arranged in a disorder. In one example, if the pitches between the light emitting elements 111 in the same row are the same, the light emitting elements 111 in the light source 11 may be considered to be regularly arranged; conversely, if the pitches between the light emitting elements 111 in the same row are different, or there is no correlation between the pitches between the light emitting elements 111 in the same row, it can be considered that the light emitting elements 111 in the light source 11 are arranged in disorder. The light source 11 includes a plurality of rows of light emitting elements 111, and each row of light emitting elements 111 includes a plurality of light emitting elements 111. In one example, if the intervals between the columns are the same, the plurality of light emitting elements 111 in the light source 11 may be considered to be regularly arranged; on the contrary, if the intervals between the columns are not the same or there is no correlation between the intervals between the columns, the plurality of light emitting elements 111 in the light source 11 may be considered to be arranged in a random manner. In one example, if the pitches between the light emitting elements 111 in the same column are the same, the light emitting elements 111 in the light source 11 may be considered to be regularly arranged; on the contrary, if the pitches between the light emitting elements 111 in the same column are different, or there is no correlation between the pitches between the light emitting elements 111 in the same column, it can be considered that the light emitting elements 111 in the light source 11 are arranged in a random manner.
In particular, in some embodiments, the speckles in the speckle pattern are regularly arranged, which facilitates subsequent finding of corresponding speckles for obtaining depth information. In some embodiments, the speckle pattern is formed by a plurality of planar patterns, and there is a gap between each planar pattern in the speckle pattern, that is, each planar pattern in the speckle pattern is not overlapped with each other, which is beneficial for finding out the corresponding speckle to obtain the depth information.
Referring to fig. 7, in some embodiments, the light source 11 includes a first light emitting element group 101 and a second light emitting element group 102, and the first light emitting element group 101 and the second light emitting element group 102 include a plurality of light emitting elements 111. When the light source 11 emits the planar pattern, the first light emitting element group 101 and the second light emitting element group 102 are turned on at intervals, and a time difference between turning on the first light emitting element group 101 and turning on the second light emitting element group 102 is smaller than a preset time. Since the first light emitting element group 101 and the second light emitting element group 102 are turned on at intervals, and the time difference between turning on the first light emitting element group 101 and turning on the second light emitting element group 102 is smaller than the preset time, the power consumption of the light emitting module 10 can be reduced without reducing the number of light emitting points formed by emitting light beams by the light emitting elements 111 in the planar pattern.
For example, when the light source 11 emits the planar pattern, the first light emitting element group 101 is turned on first, the plurality of light emitting elements 111 in the first light emitting element group 101 are made to emit light beams, then the second light emitting element group 102 is turned on, the plurality of light emitting elements 111 in the second light emitting element group 102 are made to emit light beams, and the time difference between turning on the first light emitting element group 101 and turning on the second light emitting element group 102 is less than the preset time. For example, as shown in fig. 7, in some embodiments, it is assumed that the plurality of light emitting elements 111 in the light source 11 are regularly arranged in 5 columns, where the plurality of light emitting elements 111 arranged in the 1 st, 3 rd and 5 th columns are the first light emitting element group 101, and the plurality of light emitting elements 111 arranged in the 2 nd and 4 th columns are the second light emitting element group 102. When the light source 11 emits the planar pattern, the first light emitting element group 101, i.e., the plurality of light emitting elements 111 arranged in the 1 st, 3 rd and 5 th columns emit light beams, is turned on, then the second light emitting element group 102, i.e., the plurality of light emitting elements 111 arranged in the 2 nd and 4 th columns emit light beams, is turned on, and the time difference between turning on the first light emitting element group 101 and turning on the second light emitting element group 102 is less than the preset time. The light beams emitted from all the light emitting elements 111 in the light source 11 form a planar pattern. Of course, in some embodiments, the second light emitting element group 102 may be turned on first, and then the first light emitting element group 101 may be turned on, which is not limited herein.
In some embodiments, when the depth camera 100 operates in the first operation mode, only a portion of the light emitting elements 111 in the light source 11 may be caused to emit light beams; when the depth camera 100 operates in the second operating mode, all of the light emitting elements 111 in the light source 11 may be caused to emit light beams. For example, the first operation mode may be a mode with a low security requirement, such as a shooting mode or a ranging mode, and the second operation mode may be a mode with a high security requirement, such as payment or face recognition. On the one hand, since only a part of the light emitting elements 111 emit light beams when the depth camera 100 operates in the first operation mode, which requires less security, power consumption is reduced while depth information can be obtained; on the other hand, when the depth camera 100 operates in the second operating mode with a high requirement on security, all the light emitting elements 111 emit light beams, so that the number of scattered spots in the speckle pattern can be increased, and the accuracy of obtaining depth information can be improved.
The light source 11 is a vertical cavity surface emitting laser, and the light emitted from the vertical cavity surface emitting laser is directly incident on the diffractive optical element 12. Of course, the light source 11 may be other types of emitters, and is not limited herein.
Referring to fig. 2, 4 and 7, the diffractive optical element 12 is disposed on the light-emitting path of the light source 11, and the light-emitting elements 111 of the light source 11 emit light beams to form a planar pattern. The diffractive optical element 12 is capable of receiving a planar pattern and the diffractive optical element 12 is provided with an integrated microstructure 121 capable of collimating the planar image and replicating the planar pattern to emit a speckle pattern. As shown in fig. 3 and 4, the speckle pattern includes a zero-order region a and a plurality of first-order regions b, the plurality of first-order regions b surround the zero-order region a, and each region (including the zero-order region a and the first-order regions b) includes a plurality of speckles. The zero-order area a and the first-order area b in the speckle pattern satisfy the following conditions: gapx＝q△x，0.8<q<1.5; and gapy＝p△y，0.8<p<1.5。
Wherein, gapxThe first distance of the zero-order region a in the first direction D1 is the first-order region b. Illustratively, as shown in fig. 4, the zero order region a has two adjacent first order regions b in the first direction D1 (i.e., two first order regions b on the left and right sides of the zero order region a). Taking the first-order region b1 on the right side of the zero-order region a as an example, the distance between any line of speckles in the first-order region b1 closest to the zero-order region a and the speckle in the first direction D1 of the line corresponding to the zero-order region a closest to the first-order region b1 is the first distance gapx. Example (b)For example, the distance between the leftmost speckle in the first row of the first-order region b1 and the rightmost speckle in the first row of the zeroth-order region a is the first distance gapx(ii) a The distance between the leftmost speckle in the fourth row of the first-order region b1 and the rightmost speckle in the fourth row of the zero-order region a is also the first distance gapx. Δ x is a first distance between two adjacent speckles arranged in the same row in the zero-order region a in the first direction D1. For example, as shown in fig. 4, the first speckle and the second speckle in the fifth row of the zero-order region a from left to right are separated by a first distance Δ x in the first direction D1. That is, the first distance gap between the first-order region b and the zero-order region a in the first direction D1xIn relation to the first distance Δ x in the first direction D1 between two adjacent speckles arranged in the same row in the zero-order region a, specifically, the formula gap can be calculatedxQ Δ x, obtained by calculation. Where q is a predetermined coefficient, in some embodiments, 0.8<q<1.5。
It should be noted that, the distance between the speckle in each row of the first-order region b1 closest to the zero-order region a and the speckle in the row corresponding to the zero-order region a closest to the first-order region b1 in the first direction D1 are the same; any two adjacent speckles in the zero-order region a arranged in the same row have the same first spacing in the first direction D1. In some embodiments, the first direction D1 is the same as the direction of extent of each row of speckles in the zero order region a (or first order region b).
gapyA first distance of the zero-order region a in the second direction D2 for the first-order region b. Illustratively, as shown in fig. 4, the zero order region a has two adjacent first order regions b in the second direction D2 (i.e., two first order regions b on the upper and lower sides of the zero order region a). Taking the first-order region b2 on the upper side of the zero-order region a as an example, the distance between any row of speckles in the first-order region b2 closest to the zero-order region a and the row of speckles corresponding to the zero-order region a closest to the first-order region b2 in the second direction D2 is the second distance gapy. For example, the distance between the lowest speckle in the third column of the first-order region b2 and the lowest speckle in the third row of the zero-order region a is the second distance gapy. Δ y is a second spacing of two adjacent rows of speckles in the zero-order region a in the second direction D2. E.g. zero as shown in fig. 4The second distance Δ y is defined as the distance between the second row and the third row of the stage area a in the second direction D2. That is, the second distance gap between the first order region b and the zero order region a in the second direction D2yThe first distance Δ y in the second direction D2 between the speckles of two adjacent lines in the zero-order region a is related to, and specifically, can be calculated by the formula gapyAnd p Δ y, obtained by calculation. Where p is a predetermined coefficient, in some embodiments, 0.8<q<1.5. It should be noted that, in some embodiments, the second direction D2 is the same as the extending direction of each column of speckles in the zero-order region a (or the first-order region b). In addition, q and p can take the same value or different values, and only need to satisfy 0.8<q<1.5 and 0.8<q<1.5, and is not limited herein.
In some embodiments, integrated microstructure 121 is designed based on reference module 30 (shown in fig. 5). The vertical distance between the light source 11 and the diffractive optical element 12 is related to the object distance of the light emitting module 10 and the effective focal length of the collimating lens set 31 in the reference module 30.
Specifically, referring to fig. 2 and 5, the reference module 30 includes a light emitting element 33, a collimating lens group 31 and a first optical element 32 sequentially disposed along a light emitting path. The light emitting assembly 33 is used for emitting a light beam to form a second image, the collimating lens group 31 is used for receiving the second pattern emitted by the light emitting assembly 33 and collimating the second pattern, and the first optical element 32 is used for receiving the collimated second pattern and duplicating the plane pattern to emit the first pattern. The first pattern is a speckle pattern and the second pattern is a planar pattern. The number, arrangement and light emitting power of the light emitting elements in the light source 11 of the light emitting module 10 are the same as the number, arrangement and light emitting power of the light emitting elements in the light emitting module 33 of the reference module 30, that is, the planar pattern emitted by the light source 11 is substantially the same as the second pattern emitted by the light emitting module 33. The integrated microstructure 121 on the diffractive optical element 12 in the light emitting module 10 is designed according to the first pattern emitted from the reference module 30 and the light beam emitted from the light emitting element 33 to form a second pattern, so that the speckle pattern emitted from the planar pattern emitted from the light source 11 after passing through the diffractive optical element 12 is substantially consistent with the first pattern emitted from the reference module 30. For example, in one example, a planar phase variation profile can be obtained based on the electromagnetic wave vector theory according to the input (i.e., the light beam emitted by the light emitting element 33) and output (i.e., the first pattern emitted by the reference module 30) light waves, and the phase variation can be realized by using the optical path difference caused by the medium, so as to design the integrated microstructure 121 on the diffractive optical element 12. Of course, the integrated microstructure 121 may be designed based on the reference module 30 in other ways, and it is only necessary to satisfy that when the light emitting module 10 emits the planar pattern using the same light source as the reference module 30, the speckle pattern finally emitted by the light emitting module 10 is substantially consistent with the first pattern (i.e., speckle pattern) emitted by the reference module 30.
When the integrated microstructure 121 is designed based on the reference module 30, in some embodiments, the vertical distance between the light source 11 and the diffractive optical element 12 can be related to the object distance of the light emitting module 10 and the effective focal length of the collimating lens group 31 in the reference module 30. Specifically, in some embodiments, the perpendicular distance between the light source 11 and the diffractive optical element 12 may be calculated by the formula v ═ EFLGinseng radix (Panax ginseng C.A. Meyer)×u/u-EFLGinseng radix (Panax ginseng C.A. Meyer)And (6) calculating. Where v is the perpendicular distance between the light source 11 and the diffractive optical element 12; EFLGinseng radix (Panax ginseng C.A. Meyer)Is the effective focal length of the collimating lens group 31 in the reference module 30; u is the object distance of the light emitting module 10. In particular, in some embodiments, the perpendicular distance between the light source 11 and the plane where the integrated microstructures 121 are located may be taken as the perpendicular distance v between the light source 11 and the diffractive optical element 12.
In addition, the light emitting module 10 also has a certain requirement for assembly tolerance (i.e. the vertical distance between the light source 11 and the diffractive optical element 12, which will not be described in detail below). For example, when the assembly tolerance is large, the spot dispersion may be caused to be larger, but when the assembly tolerance is in the range of <30um, the spot dispersion is not caused to be larger. Therefore, in some embodiments, the light emitting module 10 has an assembly tolerance of <30um, i.e. the perpendicular distance between the light source 11 and the diffractive optical element 12 is <30um, to avoid causing an enlarged spot dispersion.
In some embodiments, the perpendicular distance between the light source 11 and the diffractive optical element 12 may also be equal toThe object distance of the light emitting module 10 is related to the effective focal length of the diffractive optical element 12. Specifically, in some embodiments, the perpendicular distance between the light source 11 and the diffractive optical element 12 may be calculated by the formula v ═ EFLDiffraction of×u/u-EFLDiffraction ofAnd (6) calculating. Where v is the perpendicular distance between the light source 11 and the diffractive optical element 12; EFLDiffraction ofIs the effective focal length of the diffractive optical element 12; u is the object distance of the light emitting module 10. Likewise, in some embodiments, the vertical distance between the light source 11 and the plane where the integrated microstructures 121 are located may be taken as the vertical distance v between the light source 11 and the diffractive optical element 12.
Referring to fig. 6 to 9, in some embodiments, the viewing angle of the light emitting module 10, the length X of the planar pattern in the first direction D1, the length Y of the planar pattern in the second direction D2, the effective focal length EFL of the diffractive optical element 12, and the first distance gapxAnd a second distance gapyIt is related.
As shown in fig. 7, the light source 11 includes a short side 1101 and a long side 1102 adjacent to each other, and the long side 1102 is longer than the short side 1101, wherein the short side 1101 extends in the same direction as the columns formed by the plurality of light emitting elements 111 arranged in rows, and the long side 1102 extends in the same direction as the rows formed by the plurality of light emitting elements 111 arranged in rows. In one example, the light source 11 shown in fig. 7 includes a plurality of light emitting elements 111 arranged regularly to form a matrix, i.e., a plurality of rows of light emitting elements 111 are aligned one by one. In another example, as shown in FIG. 8, the light source 11 includes a plurality of light emitting elements 111 that are offset along the long side 1102, i.e., the rows of light emitting elements 111 are offset from each other. In another example, as shown in fig. 9, the light source 11 includes a plurality of light emitting elements 111 that are offset along the short side 1101, i.e., the light emitting elements 111 in a plurality of rows are offset from each other.
In some embodiments, as shown in fig. 6(a), the length of the planar pattern in the first direction D1 may be a distance between a straight line passing through the centers of the leftmost column of light-emitting points of the planar pattern and a straight line passing through the centers of the rightmost column of light-emitting points of the planar pattern; alternatively, in some embodiments, as shown in fig. 6(b), the length X of the planar pattern in the first direction D1 may also be a distance between a tangent line passing through the left side of the leftmost column of light-emitting points of the planar pattern and a tangent line passing through the right side of the rightmost column of light-emitting points of the planar pattern. Of course, in some embodiments, the length X of the planar pattern in the first direction D1 may also be the distance between a tangent line passing through the left side of the leftmost column of light-emitting points of the planar pattern and a tangent line passing through the left side of the rightmost column of light-emitting points of the planar pattern; alternatively, in some embodiments, the length X of the planar pattern in the first direction D1 may also be a distance between a tangent line passing through the right side of the leftmost column of light-emitting points of the planar pattern and a tangent line passing through the right side of the rightmost column of light-emitting points of the planar pattern; and are not intended to be limiting herein.
Similarly, in some embodiments, as shown in fig. 6(a), the length Y of the planar pattern in the second direction D2 may be a distance between a straight line passing through the center of the uppermost row of light-emitting points of the planar pattern and a straight line passing through the center of the lowermost row of light-emitting points of the planar pattern; alternatively, in some embodiments, as shown in fig. 6(b), the length Y of the planar pattern in the second direction D2 may also be a distance between a tangent line passing through an upper side of the uppermost row of light-emitting points of the planar pattern and a tangent line passing through a lower side of the lowermost row of light-emitting points of the planar pattern. Of course, in some embodiments, the length Y of the planar pattern in the second direction D2 may also be a distance between a tangent line passing through an upper side of the uppermost row of light-emitting points of the planar pattern and a tangent line passing through an upper side of the lowermost row of light-emitting points of the planar pattern; alternatively, in some embodiments, the length Y of the planar pattern in the second direction D2 may be a distance between a tangent line passing through a lower side of the uppermost row of the light emitting points of the planar pattern and a tangent line passing through a lower side of the lowermost row of the light emitting points of the planar pattern, which is not limited herein.
Specifically, the first direction D1 corresponds to the horizontal direction, and the second direction D2 corresponds to the vertical direction. In some embodiments, the field angle of the zero-order region a of the speckle pattern in the horizontal direction is related to the length X of the planar pattern in the first direction D1, and the effective focal length EFL of the diffractive optical element 12. As an example of this, the following is given,
Figure BDA0003325885490000081
where X is the length of the planar pattern in the first direction D1 and EFL is the effective focal length of the diffractive optical element 12. Further, in some embodiments, the field angle θ of the zero-order region a of the speckle pattern in the horizontal directionHAt a first distance gapxSatisfy the calculation formula
Figure BDA0003325885490000082
Wherein theta isHThe angle of view of the zero-order region a in the horizontal direction. In some implementations, the field angle of the zero-order region a in the horizontal direction may be an angle between a line connecting the centers of the speckles located in the middle of the leftmost column of the zero-order region a to the light source 11 and a line connecting the centers of the speckles located in the middle of the rightmost column of the zero-order region a to the light source 11; alternatively, in some embodiments, the field angle of the zero-order region a in the horizontal direction may be an angle between a line drawn from the leftmost of the speckles located in the middle of the leftmost column of the zero-order region a to the light source 11 and a line drawn from the rightmost of the speckles located in the middle of the rightmost column of the zero-order region a to the light source 11.
Likewise, in some embodiments, the vertical field angle of the zero-order region a of the speckle pattern is related to the length Y of the planar pattern in the second direction D2, and the effective focal length EFL of the diffractive optical element 12. As an example of this, the following is given,
Figure BDA0003325885490000083
where Y is the length of the planar pattern in the second direction D2 and EFL is the effective focal length of the diffractive optical element 12. Further, in some embodiments, the field angle θ of the zero-order region a of the speckle pattern in the vertical directionVSatisfies the calculation formula with the second distance gapy
Figure BDA0003325885490000084
Figure BDA0003325885490000085
Wherein theta isvThe angle of view of the zero-order region a in the vertical direction. Note that in some implementations, the zero order regionThe field angle of the a in the vertical direction can be an included angle between a connecting line from the center of the speckle in the middle of the uppermost line of the zero-order region a to the light source 11 and a connecting line from the center of the speckle in the middle of the lowermost line of the zero-order region a to the light source 11; alternatively, in some embodiments, the vertical field angle of the zero-order region a may be an angle between a line connecting an uppermost point of speckles located in the middle of an uppermost row of the zero-order region a to the light source 11 and a line connecting a lowermost point of speckles located in the middle of a lowermost row of the zero-order region a to the light source 11.
In some embodiments, the speckle pattern includes a plurality of regions of different levels, with the high level regions being peripheral to the low level regions. For example, as shown in fig. 3, the speckle pattern includes a zero-order region a and a first-order region b, the first-order region b is at the periphery of the zero-order region a; for another example, as shown in fig. 10, the speckle pattern includes a zero-order region a, a first-order region b and a second-order region c, the first-order region b is at the periphery of the zero-order region a, and the second-order region c is at the periphery of the first-order region b. The first direction D1 corresponds to the horizontal direction, and the second direction D2 corresponds to the vertical direction. The field angles of the light emission module 10 include a horizontal field angle FOV-X and a vertical field angle FOV-Y.
It should be noted that, in some embodiments, the horizontal field angle FOV-X of the light emitting module 10 may be an angle between a line connecting the center of the speckle in the middle of the leftmost column of the speckle pattern to the light source 11 and a line connecting the center of the speckle in the middle of the rightmost column of the speckle pattern to the light source 11; alternatively, in some embodiments, the horizontal field angle FOV-X of the light emission module 10 may be an angle between a line connecting the leftmost of the speckles located in the middle of the leftmost column of the speckle pattern to the light source 11 and a line connecting the rightmost of the speckles located in the middle of the rightmost column of the speckle pattern to the light source 11. Similarly, in some embodiments, the vertical field angle FOV-Y of the light emitting module 10 may be an angle between a line connecting the center of the speckle located in the middle of the uppermost row of the speckle pattern to the light source 11 and a line connecting the center of the speckle located in the middle of the lowermost row of the speckle pattern to the light source 11; alternatively, in some embodiments, the vertical field angle FOV-Y of the light emitting module 10 may be an angle between a line connecting the top of the speckles located in the middle of the top row of the speckle pattern to the light source 11 and a line connecting the bottom of the speckles located in the middle of the bottom row of the speckle pattern to the light source 11, which is not limited herein.
Further, in some embodiments, the horizontal field angle FOV-X is related to the length X of the planar pattern in the first direction D1, the effective focal length EFL of the diffractive optical element 12, the first distance gapxAnd the maximum level that the speckle pattern has in the first direction D1. In particular, it is possible to calculate the formula
Figure BDA0003325885490000091
And
Figure BDA0003325885490000092
and (6) calculating. Where X is the length of the planar pattern in the first direction D1, EFL is the effective focal length of the diffractive optical element 12, gapxAt the first distance, e is the maximum order level that the speckle pattern has in the first direction D1. Note that, as shown in fig. 11, if only the zero-order region a and the first-order region b exist in the first direction D1, e is 1; as shown in fig. 12, there are the zero-level region a, the first-level region b, and the second-level region c in the first direction D1, and e is 2.
Likewise, in some embodiments, the vertical field angle FOV-Y is related to the length Y of the planar pattern in the second direction D2, the effective focal length EFL of the diffractive optical element 12, the second distance gapyAnd the maximum level that the speckle pattern has in the second direction D2. In particular, it is possible to calculate the formula
Figure BDA0003325885490000093
And
Figure BDA0003325885490000094
and (6) calculating. Where Y is the length of the planar pattern in the second direction D2, EFL is the effective focal length of the diffractive optical element 12, gapyAt the second distance, f is the maximum order level that the speckle pattern has in the second direction D2. To be noted are, for exampleIn FIG. 12, in the second direction D2, if there are only the zero-order region a and the first-order region b, f is 1; as shown in fig. 11, in the second direction D2, there are the zero-level region a, the first-level region b, and the second-level region c, and f is 2.
In some embodiments, the integrated microstructure 121 is formed by the fusion of a virtual phase-based first microstructure and a virtual second microstructure. The first microstructure is used for collimating light rays, and the second microstructure is used for copying light spots formed by received light rays. For example, in some embodiments, the first microstructure is a microstructure of an n-step diffractive lens (as shown in fig. 13 (a)) or a microstructure of a superlens (as shown in fig. 13 (b)), where n is greater than or equal to 2. Such that the first microstructure can be used to collimate light. For another example, in some embodiments, the second microstructure is a grating-based diffractive microstructure (as shown in fig. 14 (a)) or a superlens-based diffractive microstructure (as shown in fig. 14 (b)). The second microstructure can thus be used to replicate the spot formed by the received light.
For example, as shown in fig. 15, the upper left diagram is a schematic diagram of a first microstructure for collimating light, the upper left diagram is a schematic diagram of a second microstructure for replicating a light spot formed by received light, and the right diagram is a schematic diagram of an integrated microstructure 121 formed by fusing the first microstructure and the second microstructure. Because the integrated microstructure 121 is formed by fusing a virtual phase-based first microstructure and a virtual second microstructure, the integrated microstructure 121 can collimate a planar pattern and copy the planar pattern to emit a speckle pattern, so that the light emitting module 10 can realize a better light projection effect without arranging a plurality of optical devices, thereby reducing the volume of the light emitting module 10 and reducing the manufacturing cost of the light emitting module 10.
Referring to fig. 2, in some embodiments, the diffractive optical element 12 includes a first surface 1201 and a second surface 1202, wherein the first surface 1201 faces the light source 11, and the second surface 1202 faces away from the light source 11. That is, the light emitted from the light source 11 will enter the first surface 1201 and then exit from the second surface 1202. As shown in fig. 2, in some embodiments, integrated microstructure 121 may be disposed on first surface 1201, light emitted from light source 11 may be incident on integrated microstructure 121, and after integrated microstructure 121 collimates and replicates a planar pattern formed by light emitted from light source 11, a speckle pattern may be emitted from second surface 1202. Since the integrated microstructure 12 is disposed on the first side 1201 close to the light source 11 and intersects with the integrated microstructure 121 disposed on the second side 1202 far from the light source 11, it is beneficial to prevent the integrated microstructure 121 from being scratched and to prevent moisture and dust from entering the integrated microstructure 121, thereby prolonging the service life of the light emitting module 10. As shown in fig. 16, in some embodiments, the integrated microstructure 12 may be disposed on the second surface 1202, light emitted from the light source 11 enters the integrated microstructure 12 after entering the first surface 1201, and the integrated microstructure 12 collimates and replicates a planar pattern formed by the light emitted from the light source 11 to emit a speckle pattern. Glare may occur due to direct incidence of strong light on the integrated microstructure 122, and the stray light is relatively strong, which may affect the effect of the light emitting module 10 to emit a speckle pattern, thereby affecting the detection accuracy of the depth camera 100 (shown in fig. 1). Therefore, in this embodiment, the integrated microstructure 12 is disposed on the second surface 1202 far away from the light source 11, so that the size of the light emitting module 10 can be reduced, and simultaneously, glare and stray light can be avoided, which is beneficial to improving the effect of the light emitting module 10 for emitting speckle patterns, thereby improving the detection accuracy of the depth camera 100 (shown in fig. 1). Of course, in some embodiments, the integrated microstructures 121 may also be disposed on the first side 1201 and the second side 1202, that is, the integrated microstructures 121 are disposed on both sides of the diffractive optical element 12, which is not limited herein.
Referring to fig. 17, in some embodiments, the diffractive optical element 12 includes a first layer 1203 and a second layer 1204, and the first layer 1203 is closer to the light source 11 than the second layer 124. Integrated microstructure 121 is located within a sealed cavity 1205 formed by first layer 1203 and second layer 1204. Because integrated microstructure 121 is accommodated in sealed cavity 1205, moisture and dust can be prevented from entering integrated microstructure 121, which is beneficial to prolonging the service life of light emitting module 10. The first layer 1203 and the second layer 1204 of the diffractive optical element 12 may be made of a plastic material. Of course, the first layer 1203 and the second layer 1204 of the diffractive optical element 12 may be made of other materials that can prevent water and dust, and are not limited herein.
Referring to fig. 18, in some embodiments, a filler 122 is disposed between the voids of the integrated microstructures 121. Therefore, on one hand, moisture and dust can be prevented from entering the gaps of the integrated microstructures 121, and the service life of the light emitting module 10 is prolonged; on the other hand, the light beam emitted by the light source 11 can be prevented from directly entering the human eye through the gap between the integrated microstructures 121, thereby improving the safety of the light emitting module 10. It is noted that in some embodiments, the filler 122 may comprise an organic or silicon dioxide.
Referring to fig. 19, in some embodiments, after the planar pattern passes through integrated microstructure 121, integrated microstructure 121 can replicate the planar pattern into M × N pieces, and the plurality of planar patterns (i.e., M × N pieces) form a speckle pattern. Wherein M is greater than or equal to 3, N is greater than or equal to 3, and M and N are both odd numbers. Since the integrated microstructure 121 can reproduce a planar pattern in M × N, the range over which the speckle pattern can be projected, that is, the range over which the depth camera 100 (shown in fig. 1) can measure, can be extended.
The integrated microstructures 121 are disposed along two symmetry axes, and specifically, as shown in the schematic diagram of the integrated microstructure on the right side of fig. 15, the integrated microstructures 121 are arranged in a substantially circular shape, and may form two mutually perpendicular symmetry axes, which are the symmetry axis S1 and the symmetry axis S2, with the circle center as the center. In some embodiments, while integrated microstructures 121 are symmetrically distributed along axis of symmetry S1, integrated microstructures 121 are also symmetrically distributed along axis of symmetry S2. Specifically, the integrated microstructures 121 on the left side of the symmetry axis S1 and the integrated microstructures on the right side of the symmetry axis S1 are distributed axisymmetrically with respect to the symmetry axis S1; the integrated microstructures 121 on the upper side of the symmetry axis S2 and the integrated microstructures on the lower side of the symmetry axis S1 are distributed axisymmetrically with respect to the symmetry axis S2. Note that the symmetry axis S1 and the symmetry axis S2 are virtual and do not exist in reality.
For example, as shown in the schematic diagram of the integrated microstructures on the right side of fig. 15, assuming that the straight line F1 and the straight line F2 are both perpendicular to the symmetry axis S1 and are both parallel to the symmetry axis S2, and the straight line F3 and the straight line F4 are both perpendicular to the symmetry axis S2 and are both parallel to the symmetry axis S1, if the symmetry axis S1 is taken as a boundary, the integrated microstructures 121 on the straight line F1 and on the left side of the symmetry axis S1 and the integrated microstructures 121 on the straight line F1 and on the right side of the symmetry axis S1 are symmetrically distributed about the symmetry axis S1, and the integrated microstructures 121 on the straight line F2 and on the left side of the symmetry axis S1 and the integrated microstructures 121 on the straight line F2 and on the right side of the symmetry axis S1 are symmetrically distributed about the symmetry axis S1; similarly, if the symmetry axis S2 is defined as a boundary, the integrated microstructures 121 on the line F3 and above the symmetry axis S2 and the integrated microstructures 121 on the line F3 and below the symmetry axis S2 are symmetrically distributed about the symmetry axis S2, and the integrated microstructures 121 on the line F4 and above the symmetry axis S2 and the integrated microstructures 121 on the line F4 and below the symmetry axis S2 are symmetrically distributed about the symmetry axis S2.
In addition, among a plurality of straight lines perpendicular to the symmetry axis S1 and parallel to the symmetry axis S2, there are a first straight line pair having the same distance to the symmetry axis S2 and a second straight line pair having different distances to the symmetry axis S2, and the integrated microstructures 121 on the first straight line pair are distributed the same and the integrated microstructures 121 on the second straight line pair are different. For example, assume that the straight lines F1, F2, and F5 are perpendicular to the symmetry axis S1 and parallel to the symmetry axis S2, among three straight lines, i.e., the straight lines F1, F2, and F5, the straight line F1 and the straight line F2 have the same distance to the symmetry axis S2 and form a first straight line pair, the straight line F1 and the straight line F5 have different distances to the symmetry axis S2 and form a second straight line pair, the straight line F2 and the straight line F5 have different distances to the symmetry axis S2 and form a second straight line pair, the straight line F1 and the straight line F2 have the same distribution of integrated microstructures 121, the straight line F1 and the straight line F5 have different integrated microstructures 121, and the straight line F2 and the straight line F5 have different integrated microstructures 121. Similarly, among the plurality of straight lines perpendicular to the symmetry axis S2 and parallel to the symmetry axis S1, there are a third straight line pair having the same distance to the symmetry axis S1 and a fourth straight line pair having different distances to the symmetry axis S1, the integrated microstructures 121 on the third straight line pair are distributed in the same distribution, and the integrated microstructures 121 on the fourth straight line pair are different.
In some embodiments, the two axes of symmetry are perpendicular to each other, which enables the M x N planar images obtained after replication to be arranged in a one-to-one correspondence (as shown in fig. 19). In particular, in some embodiments, the two axes of symmetry are not perpendicular, such that in a speckle pattern formed by M x N planar patterns, the planar patterns between adjacent columns are misaligned (as shown in fig. 20). Of course, in some embodiments, the speckle pattern formed by the M × N planar patterns may also be offset between adjacent rows, and is not limited herein.
In some embodiments, the diffractive optical element 12 may also be a planar phase lens, which performs the functions of collimating and replicating light. Illustratively, a planar pattern formed by light beams emitted by the plurality of light emitting elements 111 in the light source 11 can be incident on a planar phase lens, and a plurality of phase microstructures are disposed on the planar phase lens, and the phase microstructures can collimate and replicate the received planar pattern. Thus, compared with the method of using different optical elements to respectively realize the collimating and copying functions, the volume of the light emitting module 10 can be reduced, and the manufacturing cost of the light emitting module 10 can be reduced.
Referring to fig. 21, an embodiment of the present application further provides a terminal 1000. Terminal 1000 can include a housing 200 and a depth camera 100 as described in any of the embodiments above, depth camera 100 being coupled to housing 200. It should be noted that the terminal 1000 may be a mobile phone, a computer, a tablet computer, an intelligent watch, an intelligent wearable device, and the like, which is not limited herein.
Terminal 1000 of this application, through integrated micro-structure 121 collimation plane pattern on the diffraction optical element 12 among the light emission module 10, and duplicate the plane pattern with the emergent speckle pattern to zero order district a and first order district b in the speckle pattern that forms can also satisfy the gapx＝q△x，0.8<q<1.5; and gapy＝p△y，0.8<p<1.5. On one hand, compared with the method that different optical elements are adopted to respectively realize the functions of collimation and replication, the light emitting module 10 can reduce the volume of the light emitting module 10 and reduce the manufacturing cost of the light emitting module 10 on the premise of not influencing the optical effect of projecting speckle images, so that the volume and the cost of the depth camera 100 are reduced; on the other hand, the gap can be satisfied because the zero-order region and the first-order region in the speckle patternx＝q△x，0.8<q<1.5; and gapy＝p△y，0.8<p<1.5, which can satisfy the follow-upThe requirement of software calculation can quickly and accurately find the zero-order area a and the first-order area b in the speckle pattern, and the efficiency and the accuracy of depth information acquisition are favorably improved.
Referring to fig. 2 and 22, the present disclosure further provides a method for manufacturing the light emitting module 10 according to any one of the above embodiments. For example, the light emitting module 10 is manufactured to include a light source 11 and a diffractive optical element 12. The light source 11 includes a plurality of light emitting elements 111 and serves to emit light beams to form a planar pattern. The diffractive optical element 12 is provided with an integrated microstructure 121, the integrated microstructure 121 being capable of collimating a planar pattern and replicating the planar pattern to emit a speckle pattern. The speckle pattern comprises a zero-order area a and a plurality of first-order areas b surrounding the zero-order area a, and the zero-order area a and the first-order areas b meet the following conditions: gapx＝q△x，0.8<q<1.5; and gapy＝p△y，0.8<p<1.5. Wherein, gapxA first distance, gap, between the first order region b and the zero order region a in a first direction D1yThe second distance between the first-order region b and the zero-order region a in the second direction D2, Δ x is a first distance between two adjacent speckles arranged in the same row in the zero-order region a in the first direction D1, and Δ y is a second distance between two adjacent speckles in the zero-order region a in the second direction D2.
Specifically, the manufacturing method includes:
01: acquiring a first pattern formed by emission of a reference module; the reference module comprises a light-emitting component, a collimating lens group and a first optical element, wherein the light-emitting component can emit a light beam to form a second pattern, the collimating lens group is used for collimating the second pattern, the first optical element is used for copying the second pattern to emit the first pattern, the first pattern is a speckle pattern, and the second pattern is a plane pattern;
02: designing a diffractive optical element of the light emitting module according to the first pattern and the second pattern so that the second pattern can emit the first pattern after passing through the diffractive optical element; designing a light source of the light emitting module according to the light emitting component so that a light beam emitted by the light source can form a second image; and
03: the diffractive optical element is assembled in the light-emitting direction of the light source to obtain the light-emitting module.
Illustratively, in some embodiments, a reference module 30 (shown in fig. 5) is obtained, and the reference module 30 includes a light emitting component 33, a collimating lens group 31, and a first optical element 32, which are sequentially disposed along a light emitting optical path. The light emitting assembly 33 is configured to emit a light beam to form a second pattern, the collimating lens group 31 is configured to receive the second pattern emitted by the light emitting assembly 33 and collimate the second pattern, the first optical element 32 is configured to receive the collimated second pattern and copy the second pattern to emit a first pattern, where the first pattern is a speckle pattern and the second pattern is a planar pattern.
After acquiring the first pattern emitted by the reference module 30, the diffractive optical element 12 in the light emitting module 10 is designed according to the first pattern emitted by the reference module 30 and the emitted light beam in the light emitting assembly 33 to form a second pattern, so that the second pattern can emit the first pattern after passing through the diffractive optical element 12.
Specifically, in some embodiments, the integrated microstructure 121 on the diffractive optical element 12 is designed according to the first pattern emitted by the reference module 30 and the light beam emitted from the light emitting assembly 11 to form the second pattern, so that the second pattern emitted by the light emitting assembly 33 can emit a speckle pattern after passing through the diffractive optical element 12, and the emitted speckle pattern is substantially identical to the first pattern emitted by the reference module 30. For example, in one example, a planar phase variation profile can be obtained based on the electromagnetic wave vector theory according to the input (i.e., the light beam emitted by the light emitting element 33) and output (i.e., the first pattern emitted by the reference module 30) light waves, and the phase variation can be realized by using the optical path difference caused by the medium, so as to design the integrated microstructure 121 on the diffractive optical element 12.
The light source 11 of the light emitting module 10 is designed according to the light emitting assembly 33, so that the light beam emitted by the light source 11 can form the first image. For example, in some embodiments, the light emitting assembly 33 includes a plurality of light emitting elements, the light source 11 also includes a plurality of light emitting elements, and the number, arrangement and light emitting power of the plurality of light emitting elements in the light source 11 are all the same as those of the plurality of light emitting elements in the light emitting assembly 33. After obtaining the light source 11 and the diffractive optical element 12, the diffractive optical element 12 is assembled in the light emitting direction of the light source 11, so that the light emitting module 10 can be obtained.
Referring to fig. 2, 3 and 4, the light emitting module 10 obtained includes a light source 11 and a diffractive optical element 12. The light source 11 includes a plurality of light emitting elements 111 and serves to emit light beams to form a planar pattern. The diffractive optical element 12 is provided with an integrated microstructure 121, the integrated microstructure 121 being capable of collimating a planar pattern and replicating the planar pattern to emit a speckle pattern. The speckle pattern comprises a zero-order area a and a plurality of first-order areas b surrounding the zero-order area a, and the zero-order area a and the first-order areas b meet the following conditions: gapx＝q△x，0.8<q<1.5; and gapy＝p△y，0.8<p<1.5。
In the description herein, reference to the description of the terms "certain embodiments," "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means 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 application. 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.
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, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the feature. In the description of the present application, "a plurality" means at least two, e.g., two, three, unless specifically limited otherwise.
Although embodiments of the present application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present application, and that variations, modifications, substitutions and alterations of the above embodiments may be made by those of ordinary skill in the art within the scope of the present application, which is defined by the claims and their equivalents.

Claims (16)

1. The utility model provides a depth camera which characterized in that, includes light emission module and light receiving module, the light emission module includes:
a light source including a plurality of light emitting elements and emitting light beams to form a planar pattern; and
a diffractive optical element provided with an integrated microstructure capable of collimating the planar pattern and replicating the planar pattern to exit a speckle pattern; the speckle pattern comprises a zero-order region and a plurality of first-order regions surrounding the zero-order region, and the zero-order region and the first-order regions meet the following conditions:
gapx＝q△x，0.8<q<1.5；
gapy＝p△y，0.8<p<1.5；
wherein, gapxA first distance, gap, in a first direction between the first order region and the zero order regionyThe second distance between the first-order region and the zero-order region in the second direction is represented by Δ x, which is a first distance between two adjacent speckles arranged in the same row in the zero-order region in the first direction, and Δ y, which is a second distance between two adjacent rows of speckles in the zero-order region in the second direction;
the light receiving module is used for receiving at least part of the light reflected by the object and converting the light into an electric signal.
2. The depth camera of claim 1, wherein the plurality of light emitting elements are arranged in a regular pattern.
3. The depth camera of claim 2, wherein the speckle pattern comprises a plurality of speckles, the speckles being arranged in a regular pattern; and/or
The speckle pattern is formed of a plurality of the planar patterns, and a gap exists between each of the planar patterns in the speckle pattern.
4. The depth camera of claim 1, wherein the light source comprises a first light emitting element group and a second light emitting element group, each of the first light emitting element group and the second light emitting element group comprises a plurality of light emitting elements, the first light emitting element group and the second light emitting element group are turned on at intervals when the light source emits the planar pattern, and a time difference between turning on the first light emitting element group and turning on the second light emitting element group is less than a preset time.
5. The depth camera of claim 1, wherein a vertical distance between the light source and the diffractive optical element is related to an object distance of the light emitting module and an effective focal length of the diffractive optical element.
6. The depth camera of claim 1, wherein a field angle of the light emitting module is related to a length of the planar pattern in a first direction, a length of the planar pattern in a second direction, an effective focal length of the diffractive optical element, the first distance, and the second distance.
7. The depth camera of claim 1, wherein the field angle of the zeroth order region in the horizontal direction is related to the length of the planar pattern in the first direction and the effective focal length of the diffractive optical element;
the angle of field of the zero order region in the vertical direction is related to the length of the planar pattern in the second direction and the effective focal length of the diffractive optical element.
8. The depth camera of claim 1, wherein the integrated microstructure is formed by a fusion of a virtual phase-based first microstructure for collimating light and a virtual phase-based second microstructure for replicating a spot of light formed by received light.
9. The depth camera of claim 5, wherein the first microstructure is a microstructure of an n-step diffractive lens or a microstructure of a superlens, wherein n is greater than or equal to 2; and/or
The second microstructure is a grating-based diffractive microstructure or a superlens-based diffractive microstructure.
10. The depth camera of claim 1, wherein the light source is a vertical cavity surface emitting laser, and wherein the outgoing light of the vertical cavity surface emitting laser is directly incident on the diffractive optical element.
11. The depth camera of claim 1, wherein the diffractive optical element comprises a first face facing the light source and a second face facing away from the light source, the integrated microstructure being provided on the first face or the second face; or
The diffractive optical element includes a first layer and a second layer, and the integrated microstructure is located within a sealed cavity formed by the first layer and the second layer.
12. The depth camera of claim 1, wherein a filler is disposed between the voids of the integrated microstructures, the filler comprising an organic or silicon dioxide.
13. The depth camera of claim 1, wherein the integrated microstructures replicate the planar pattern by M x N, wherein the plurality of planar patterns form the speckle pattern, wherein M is equal to or greater than 3, N is equal to or greater than 3, and both M and N are odd numbers.
14. The depth camera of claim 10, wherein the planar pattern between adjacent columns is misaligned or the planar pattern between adjacent rows is misaligned in the speckle pattern formed from the M x N planar images.
15. A method of manufacturing a light emitting module according to any of claims 1-14, comprising:
acquiring a first pattern formed by emission of a reference module; the reference module comprises a light-emitting component, a collimating lens group and a first optical element, wherein the light-emitting component can emit a light beam to form a second pattern, the collimating lens group is used for collimating the second pattern, the first optical element is used for copying the second pattern to emit the first pattern, the first pattern is a speckle pattern, and the second pattern is a plane pattern;
designing a diffractive optical element of the light emitting module according to the first pattern and the second pattern so that the second pattern can be emitted out of the first pattern after passing through the diffractive optical element; designing a light source of the light emitting module according to the light emitting component so that the light source emits a light beam capable of forming the second image; and
and assembling the diffractive optical element in the light emergent direction of the light source to obtain the light emitting module.
16. A terminal, comprising:
a housing; and
the depth camera of any one of claims 1 to 14, in combination with the housing.
CN202111261453.6A 2021-10-28 2021-10-28 Depth camera, method for manufacturing light emitting module and terminal Pending CN114002698A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2023071650A1 (en) * 2021-10-28 2023-05-04 Oppo广东移动通信有限公司 Depth camera, method for manufacturing light-emitting module, and terminal

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20160377414A1 (en) * 2015-06-23 2016-12-29 Hand Held Products, Inc. Optical pattern projector
TWM526763U (en) * 2015-11-27 2016-08-01 高準精密工業股份有限公司 Lighting apparatus
CN107424188B (en) * 2017-05-19 2020-06-30 深圳奥比中光科技有限公司 Structured light projection module based on VCSEL array light source
CN107450190B (en) * 2017-09-08 2019-12-13 深圳奥比中光科技有限公司 Diffraction optical element and preparation method
CN111522190B (en) * 2019-02-01 2022-03-11 无锡奥普顿光电子有限公司 Projection device based on surface emitting laser and manufacturing method thereof
CN111399245A (en) * 2020-05-13 2020-07-10 浙江水晶光电科技股份有限公司 Laser emission module and 3D imaging device
CN111694161A (en) * 2020-06-05 2020-09-22 Oppo广东移动通信有限公司 Light emitting module, depth camera and electronic equipment
CN114002698A (en) * 2021-10-28 2022-02-01 Oppo广东移动通信有限公司 Depth camera, method for manufacturing light emitting module and terminal

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2023071650A1 (en) * 2021-10-28 2023-05-04 Oppo广东移动通信有限公司 Depth camera, method for manufacturing light-emitting module, and terminal

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