CN210015299U - Laser projection module, depth camera and electronic device - Google Patents

Abstract

The application discloses laser projection module, degree of depth camera and electron device. The laser projection module comprises a light source, a collimation element and a diffraction optical element. The light source is used for emitting laser; the collimation element is used for collimating the laser; the diffraction optical element is used for diffracting the laser collimated by the collimation element to form a laser pattern, and the diffraction optical element is provided with a hydrophobic layer. In the laser projection module, the depth camera and the electronic device of this application embodiment, set up the hydrophobic layer on the diffraction optical element, can avoid because liquid gets into the laser projection module, attached to the surface of diffraction optical element, lead to the zero order laser energy reinforcing that the laser projection module throwed, harm eye safety.

Description

Laser projection module, depth camera and electronic device

Technical Field

The present application relates to the field of consumer electronics, and more particularly, to a laser projection module, a depth camera, and an electronic device.

Background

With the rapid development of electronic technology, electronic devices such as smart phones and tablet computers have become more and more popular. The laser projection module can be arranged on the electronic device and can be used for diffusing laser spots into a spot pattern with a certain angle by utilizing the diffractive optical element to project the spot pattern on an object. When the laser energy projected by the laser projection module is too strong, the safety of human eyes can be endangered.

SUMMERY OF THE UTILITY MODEL

The embodiment of the application provides a laser projection module, a depth camera and an electronic device.

The embodiment of the present application provides a laser projection module, which includes a light source, a collimating element, and a Diffractive Optical Element (DOE), where the light source is configured to emit laser light; the collimation element is used for collimating the laser; the diffraction optical element is used for diffracting the laser collimated by the collimation element to form a laser pattern, and a hydrophobic layer is arranged on the diffraction optical element.

In some embodiments, the diffractive optical element comprises opposing diffractive entrance and exit faces, the diffractive entrance face being opposite the collimating element, the hydrophobic layer being formed at the diffractive entrance face and/or the diffractive exit face.

In some embodiments, the diffractive optical element includes a light-transmissive diffractive body and a diffractive micro-structural layer formed on the diffractive body, the diffractive body includes a body incident surface and a body exit surface that are opposite to each other, the body incident surface corresponds to the diffractive incident surface, the body exit surface corresponds to the diffractive exit surface, the diffractive micro-structural layer is formed on the body incident surface, and the hydrophobic layer is formed on the diffractive incident surface.

In some embodiments, the diffractive optical element includes a light-transmissive diffractive body and a diffractive micro-structure layer formed on the diffractive body, the diffractive body includes a body incident surface and a body exit surface that are opposite to each other, the body incident surface corresponds to the diffractive incident surface, the body exit surface corresponds to the diffractive exit surface, the diffractive micro-structure layer is formed on the body exit surface, and the hydrophobic layer is formed on the diffractive exit surface.

In some embodiments, the laser projection module further comprises a lens barrel, wherein the lens barrel comprises a lens barrel side wall and a limiting protrusion protruding inwards from the lens barrel side wall; the laser projection module is characterized in that the laser projection module further comprises a waterproof rubber ring arranged between the limiting protrusion and the diffraction optical element, the waterproof rubber ring comprises a top surface and a bottom surface which are back to back, the top surface is abutted against the diffraction optical element, and the bottom surface is abutted against the limiting protrusion.

In some embodiments, the limiting protrusion is provided with an annular accommodating groove, and the waterproof rubber ring is accommodated in the accommodating groove.

In some embodiments, the material of the diffractive optical element comprises polycarbonate.

In some embodiments, the laser projection module further comprises a lens barrel and a protective cover, the lens barrel comprises a lens barrel side wall, a limiting protrusion protruding inwards from the lens barrel side wall, and a fixing protrusion protruding outwards from the lens barrel side wall, and the diffractive optical element is mounted on the limiting protrusion; the protective cover comprises a protective top wall and a protective side wall extending from the protective top wall, the protective top wall is provided with a light through hole, the light through hole corresponds to the diffractive optical element, the protective side wall is provided with a fixing hole, the protective cover covers the lens barrel, the fixing protrusion extends into the fixing hole, and the diffractive optical element is located between the limiting protrusion and the protective top wall.

In some embodiments, the protection side wall includes a plurality of protection sub side walls connected end to end in sequence, the fixing holes are formed on at least two protection sub side walls, the number of the fixing protrusions is the same as that of the fixing holes, and the fixing protrusions are corresponding in position, and each fixing protrusion extends into the corresponding fixing hole; the fixing holes are formed on at least two opposite side walls of the protector.

In some embodiments, the fixing protrusion is formed with a guiding inclined plane, the guiding inclined plane is gradually far away from the side wall of the lens barrel along a direction in which the protective cover is sleeved into the lens barrel, and the protective side wall is abutted against the guiding inclined plane in a process that the protective cover is covered on the lens barrel.

The embodiment of the application further provides a depth camera, which comprises the laser projection module, an image collector and a processor, wherein the image collector is used for collecting laser patterns projected into a target space after passing through the diffractive optical element; the processor is respectively connected with the laser projection module and the image collector and is used for processing the laser patterns to obtain depth images.

The embodiment of the present application further provides an electronic device, which includes a housing and the depth camera of the above embodiment, wherein the depth camera is combined with the housing.

In the laser projection module, the depth camera and the electronic device of this application embodiment, set up the hydrophobic layer on the diffraction optical element, can avoid because liquid gets into the laser projection module, attached to the surface of diffraction optical element, lead to the zero order laser energy reinforcing that the laser projection module throwed, harm eye safety.

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 structural diagram of an electronic device according to an embodiment of the present application;

FIG. 2 is a schematic diagram of a depth camera according to an embodiment of the present application;

fig. 3 is a schematic perspective view of a laser projection module according to an embodiment of the present disclosure;

FIG. 4 is a schematic plan view of a laser projection module according to an embodiment of the present disclosure;

fig. 5 is an exploded perspective view of a laser projection module according to an embodiment of the present disclosure;

FIG. 6 is a schematic cross-sectional view of the laser projection module shown in FIG. 4 taken along line VI-VI;

FIG. 7 is a schematic cross-sectional view of another embodiment of the present application taken along a position corresponding to the VI-VI line of the laser projection module shown in FIG. 4;

FIG. 8 is a schematic cross-sectional view of the laser projection module shown in FIG. 4 taken along line VIII-VIII;

FIG. 9 is an enlarged schematic view of portion IX of the laser projection module of FIG. 8;

FIG. 10 is a schematic perspective view of a lens barrel of a laser projector according to an embodiment of the present application;

FIG. 11 is a schematic representation of a normal diffractive microstructure according to an embodiment of the present application;

FIG. 12 is a schematic diagram of speckles when the laser projection module of the present application projects laser light normally;

FIG. 13 is a schematic representation of a diffractive microstructure according to an embodiment of the present application after feeding;

FIG. 14 is a schematic diagram of speckles when a diffraction microstructure of a laser projection module is fed with liquid and then projects laser;

fig. 15 is a schematic structural view of a diffractive optical element according to an embodiment of the present application;

fig. 16 is a schematic structural view of a diffractive optical element according to an embodiment of the present application;

fig. 17 is a schematic structural view of a diffractive optical element according to an embodiment of the present application;

fig. 18 is a schematic view of the application of a hydrophobic layer according to an embodiment of the present application;

FIG. 19 is a schematic structural diagram of a laser projection module according to an embodiment of the present disclosure;

fig. 20 is a perspective view of a protective cover of a laser projection module according to an embodiment of the present disclosure.

Detailed Description

Reference will now be made in detail to embodiments of the present application, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below by referring to the drawings are exemplary only for the purpose of explaining the embodiments of the present application, and are not to be construed as limiting the embodiments of the present application.

Referring to fig. 1, an electronic device 1000 according to an embodiment of the present disclosure includes a housing 200 and a depth camera 100. The electronic device 1000 may be a mobile phone, a tablet computer, a laptop computer, a game machine, a head display device, an access control system, a teller machine, etc., in the embodiment of the present application, the electronic device 1000 is taken as an example for illustration, it is understood that the specific form of the electronic device 1000 may be other, and is not limited herein. The depth camera 100 is disposed in the housing 200 and exposed from the housing 200 to obtain a depth image, the housing 200 can provide protection for the depth camera 100, such as dust prevention, water prevention, and falling prevention, and a hole corresponding to the depth camera 100 is formed in the housing 200, so that light passes through the hole or penetrates into the housing 200.

Referring to fig. 2, the depth camera 100 includes a laser projection module 10, an image collector 20 and a processor 30. The depth camera 100 may be formed with a projection window 40 corresponding to the laser projection module 10, and a collection window 50 corresponding to the image collector 20. The laser projection module 10 is configured to project a laser pattern to a target space through the projection window 40, and the image collector 20 is configured to collect the laser pattern modulated by a target object through the collection window 50. In one example, the laser projected by the laser projection module 10 is infrared light, and the image collector 20 is an infrared camera. The processor 30 is connected to both the laser projection module 10 and the image collector 20, and the processor 30 is configured to process the laser pattern to obtain a depth image. Specifically, the processor 30 calculates the deviation value between each pixel point in the laser pattern and each corresponding pixel point in the reference pattern by using an image matching algorithm, and further obtains the depth image of the laser pattern according to the deviation value. The image matching algorithm may be a Digital Image Correlation (DIC) algorithm. Of course, other image matching algorithms may be employed instead of the DIC algorithm. The structure of the laser projection module 10 will be further described below.

Referring to fig. 3 to 6, the laser projection module 10 includes a substrate assembly 11, a lens barrel 12, a light source 13, a collimating element 14, a Diffractive Optical Element (DOE) 15, and a protective cover 16. The collimating element 14 and the diffractive optical element 15 are arranged in sequence on the optical path of the light source 13, in particular, the light emitted by the light source 13 passes through the collimating element 14 and the diffractive optical element 15 in sequence.

Referring to fig. 5 and 6, the substrate assembly 11 includes a substrate 111 and a circuit board 112 carried on the substrate 111. The substrate 111 is used to carry the lens barrel 12, the light source 13, and the circuit board 112. The material of the substrate 111 may be plastic, such as at least one of Polyethylene Terephthalate (PET), polymethyl methacrylate (PMMA), Polycarbonate (PC), and Polyimide (PI). That is, the substrate 111 may be made of a single plastic material selected from PET, PMMA, PC, and PI. Thus, the substrate 111 is light in weight and has sufficient support strength.

The circuit board 112 may be any one of a printed circuit board, a flexible circuit board, and a rigid-flex board. The circuit board 112 may be provided with a via hole 113, the via hole 113 may be used to accommodate the light source 13, a portion of the circuit board 112 is covered by the lens barrel 12, and another portion of the circuit board extends out and may be connected to the connector 17, and the connector 17 may connect the laser projection module 10 to a main board of the electronic device 1000.

Referring to fig. 5 to 8, the lens barrel 12 is disposed on the substrate assembly 11 and forms a receiving cavity 121 together with the substrate assembly 11. Specifically, the lens barrel 12 may be connected to the circuit board 112 of the substrate assembly 11, and the lens barrel 12 and the circuit board 112 may be adhered by an adhesive to improve the air tightness of the accommodating chamber 121. Of course, the lens barrel 12 and the substrate assembly 11 may be connected in other specific ways, such as by a snap connection. The accommodating cavity 121 may be used to accommodate components such as the collimating element 14 and the diffractive optical element 15, and the accommodating cavity 121 simultaneously forms a part of the optical path of the laser projection module 10. In the embodiment of the present application, the lens barrel 12 is in a hollow cylindrical shape, and the lens barrel 12 includes a barrel sidewall 122, a limiting protrusion 123, and a fixing protrusion 127.

The barrel sidewall 122 surrounds the receiving cavity 121, and the outer wall of the barrel sidewall 122 may be formed with a positioning structure and a mounting structure to fix the position of the laser projection module 10 when the laser projection module 10 is mounted in the electronic device 1000. The lens barrel 12 includes a first surface 124 and a second surface 125 opposite to each other, wherein one opening of the receiving cavity 121 is opened on the second surface 125, and the other opening is opened on the first surface 124. The second surface 125 is bonded, for example, glued, to the circuit board 112, and the first surface 124 may be used as a bonding surface for the lens barrel 12 and the diffractive optical element 15, or as a bonding surface for the lens barrel 12 and the protective cover 16.

Referring to fig. 8 and 9, the limiting protrusion 123 protrudes inward from the barrel sidewall 122, and specifically, the limiting protrusion 123 protrudes inward from the barrel sidewall 122 into the receiving cavity 121. The limiting protrusion 123 may be continuous and annular, or the limiting protrusion 123 includes a plurality of limiting protrusions 123, and the plurality of limiting protrusions 123 are distributed at intervals. The limiting protrusion 123 forms a light passing hole 1231, the light passing hole 1231 may be a part of the accommodating cavity 121, and the laser emitted from the light source 13 passes through the light passing hole 1231 and then passes through the diffractive optical element 15. In the embodiment shown in fig. 6, the limiting protrusion 123 is located between the first surface 124 and the second surface 125, the receiving cavity 121 between the limiting protrusion 123 and the second surface 125 can be used for receiving the collimating element 14, and the receiving cavity 121 between the limiting protrusion 123 and the first surface 124 can be used for receiving the diffractive optical element 15. Meanwhile, when the laser projection module 10 is assembled, when the diffractive optical element 15 abuts against the limiting protrusion 123, the diffractive optical element 15 can be considered to be installed in place, and when the collimating element 14 abuts against the limiting protrusion 123, the collimating element 14 can be considered to be installed in place. The stopper protrusion 123 includes a stopper surface 1232, and the stopper surface 1232 is combined with the diffractive optical element 15 when the diffractive optical element 15 is mounted on the stopper protrusion 123.

Referring to fig. 5, 8, 9 and 10, a fixing protrusion 127 protrudes outward from the barrel sidewall 122, specifically, the fixing protrusion 127 protrudes outward from the outer wall of the barrel sidewall 122. The fixing protrusion 127 is located closer to the first surface 124 than to the second surface 125, and in one example, the position of the fixing protrusion 127 may correspond to the position of the limiting protrusion 123. In the embodiment of the present application, the barrel sidewall 122 includes a first section 1221 and a second section 1222 connected to each other, the first section 1221 and the second section 1222 may be integrally formed, the first surface 124 is formed on the first section 1221, and the second surface 125 is formed on the second section 1222. The outer size of the first section 1221 is smaller than the outer size of the second section 1222, the fixing protrusion 127 is formed on the first section 1221, so that after the fixing protrusion 127 protrudes from the first section 1221, the total outer size of the first section 1221 and the fixing protrusion 127 is not larger than the outer size of the second section 1222, and the fixing protrusion 127 does not cause the outer size of the lens barrel 12 to increase.

Referring to fig. 8, the light source 13 is disposed on the substrate assembly 11, specifically, the light source 13 may be disposed on the circuit board 112 and electrically connected to the circuit board 112, and the light source 13 may also be disposed on the substrate 111 and corresponding to the via 113, at this time, the light source 13 may be electrically connected to the circuit board 112 by disposing a wire. The light source 13 is used to emit laser light, which may be infrared light. In one example, the light source 13 may include a semiconductor substrate disposed on the substrate 111 and a light emitting Laser (VCSEL) disposed on the semiconductor substrate. The semiconductor substrate may be provided with a single emitting laser or with an array laser composed of a plurality of emitting lasers, and specifically, the plurality of emitting lasers may be arranged on the semiconductor substrate in a regular or irregular two-dimensional pattern.

Referring to fig. 8, the collimating element 14 may be an optical lens, and the collimating element 14 is used for collimating the laser light emitted by the light source 13. The collimating element 14 is received in the receiving cavity 121, and the collimating element 14 can be assembled into the receiving cavity 121 along a direction in which the second face 125 points to the first face 124. The collimating element 14 includes an optical portion 141 and a mounting portion 142, the mounting portion 142 is used for combining with the barrel sidewall 122 to fix the collimating element 14 in the accommodating cavity 121, in the embodiment of the present application, the optical portion 141 includes two curved surfaces located on two opposite sides of the collimating element 14. One of the curved surfaces of the collimating element 14 extends into the light passing aperture 1231.

Referring to fig. 8 and 9, the diffractive optical element 15 is mounted on the limiting protrusion 123, and specifically, the diffractive optical element 15 is combined with the limiting surface 1232 to be mounted on the limiting protrusion 123. Referring to fig. 8 and 15, the diffractive optical element 15 includes a diffractive incident surface 151 and an opposite diffractive exit surface 152, the diffractive incident surface 151 is combined with the position-limiting surface 1232, the diffractive incident surface 151 corresponds to the position-limiting surface 1232, the diffractive exit surface 152 is combined with the lower surface of the top wall 161 of the protective cover, and the diffractive exit surface 152 corresponds to the lower surface of the top wall 161 of the protective cover. In the embodiment of the present application, the diffractive entrance surface 151 is formed with a diffractive micro-structured layer 154, or the diffractive exit surface 152 is formed with a diffractive micro-structured layer 154, or both the diffractive entrance surface 151 and the diffractive exit surface 152 are formed with diffractive micro-structured layers 154. The diffractive optical element 15 is configured to diffract the laser light collimated by the collimating element 14 to form a laser light pattern corresponding to the diffractive micro-structured layer 154.

The laser wavelength emitted by the light source 13 is 940nm, and the laser beam is collimated by the collimating element 14, then is diffracted by the diffractive optical element 15 to shape and uniformly project the beam to a space, so that a speckle field is formed. The diffraction pattern of the diffractive optical element 15 is realized by multi-zone replication, and in the using process, under the conditions that water mist in a humid environment enters the laser projection module 10 and is attached to the surface of the diffractive optical element 15, and the like, the energy of the zero-order zone of the diffractive optical element 15 is obviously enhanced, and the human eyes are injured. Fig. 11 shows a normal diffractive micro-structured layer 154, the normal diffractive micro-structured layer 154 being spatially ordered. Correspondingly, fig. 12 is a speckle pattern of the laser projection module 10 when the laser is normally projected, and the normal speckle pattern is a speckle pattern formed by splicing a plurality of small speckle patterns. Fig. 13 is a diagram of the filled diffractive microstructure layer 154 after liquid inlet, and the spatial arrangement of the liquid-filled diffractive microstructure layer 154 is disordered. Correspondingly, fig. 14 is a speckle pattern when the diffraction micro-structure layer 154 of the laser projection module 10 is fed with liquid and then projects laser, and the pattern shows that the laser projection brightness in the middle area is most concentrated, which is expressed as zero-order energy enhancement, and once the laser is injected into human eyes, human eyes are easily stabbed, and the safety of the human eyes is damaged.

It is understood that the surface of the diffractive optical element is usually a very fine diffractive surface, however, during the production or use of the laser projection module, moisture or other liquid may adhere to the surface of the diffractive optical element, so that the diffraction efficiency of the diffractive optical element is reduced, and even the diffractive optical element diffracts the light beam in an unexpected direction, burning the eyes of the user.

In the present embodiment, the hydrophobic layer 18 is provided on the diffractive optical element 15. By arranging the hydrophobic layer 18 on the diffractive optical element 15, the diffractive optical element 15 can be protected, water or other liquid is prevented from damaging the diffractive optical element 15, and the problem that the energy of zero-order laser is increased and exceeds the safety standard of human eyes due to the fact that water mist in a humid environment enters the laser projection module 10 and is attached to the surface of the diffractive optical element 15 can be effectively avoided. The constituent material of the water-repellent layer 18 may be a water-repellent agent, a polymer synthetic agent, or the like. In addition, the well-sealed diffractive optical element 15 enables the laser projection module 10 to be used in high moisture and/or airborne particle environments without damaging the user's eyes or degrading the optical performance of the laser projection module 10.

Referring to fig. 15, the diffractive optical element 15 includes a diffractive incident surface 151 and a diffractive exit surface 152, which are opposite to each other, the diffractive incident surface 151 corresponds to an upper surface of the collimating element 14, and the diffractive exit surface 152 corresponds to a lower surface of a top wall 161 of the protective cover, the hydrophobic layer 18 may be formed on the diffractive incident surface 151 and/or the diffractive exit surface 152, specifically, ① the hydrophobic layer 18 is formed on the diffractive incident surface 151 and the diffractive exit surface 152 (as shown in fig. 15), ② the hydrophobic layer 18 is formed on the diffractive incident surface 151 (as shown in fig. 16), ③ the hydrophobic layer 18 is formed on the diffractive exit surface 152 (as shown in fig. 17), wherein the hydrophobic layer 18 may be formed on an entire surface of the diffractive incident surface 151 and/or the diffractive exit surface 152, or only on an intermediate region of the diffractive incident surface 151 and/or the diffractive exit surface 152 (as shown in fig. 18), for example, the hydrophobic layer 18 is formed on the diffractive exit surface 151, since laser energy of the diffractive optical element 15 converges to the intermediate level, the laser energy increases safety hazard of the zero-order laser energy, and further, the hydrophobic layer 18 is concentrated on the intermediate diffraction surface 151, and the diffraction energy of the diffractive incident surface 151 and the diffraction-enhancing optical element can be prevented from directly damaging the human eye, the human eye.

Referring to fig. 15 to 17, the diffractive optical element 15 includes a light-transmissive diffractive body 153 and a diffractive micro-structure layer 154 formed on the diffractive body 153. The diffractive body 153 may be a light-transmissive crystal or a light-transmissive diffraction grating. The diffractive body 153 includes a body incident surface 1531 and a body exit surface 1532 opposite to each other, the body incident surface 1531 corresponds to the diffractive incident surface 151, and the body exit surface 1532 corresponds to the diffractive exit surface 152.

Referring to fig. 16, in one embodiment, the diffractive micro-structure layer 154 is formed on the body incident plane 1531 and the hydrophobic layer 18 is formed on the diffractive incident plane 151. The hydrophobic layer 18 is formed on the diffraction incident surface 151, so that the liquid can be effectively prevented from being attached to the diffraction incident surface 151 after entering the laser projection module 10, the diffraction structure in the diffraction micro-structure layer 154 on the body incident surface 1531 is filled, and the laser projection module 10 generates the condition that zero-order laser energy is enhanced to further harm human eye safety.

Referring to fig. 17, in one embodiment, the diffractive micro-structured layer 154 is formed on the body exit surface 1532 and the hydrophobic layer 18 is formed on the diffractive exit surface 152. The hydrophobic layer 18 is formed on the diffraction exit surface 152, so that the liquid can be effectively prevented from attaching to the diffraction exit surface 152 after entering the laser projection module 10, the diffraction structure in the diffraction micro-structure layer 154 on the body exit surface 1532 is filled, and the laser projection module 10 generates the condition that zero-order laser energy is enhanced to further harm human eye safety.

Referring to fig. 15, in one embodiment, the diffractive micro-structure layer 154 may also be formed on the body incident plane 1531 and the body exit plane 1532, and correspondingly, the hydrophobic layer 18 may also be formed on the diffractive incident plane 151 and the diffractive exit plane 152. The hydrophobic layer 18 is formed on the diffraction incident surface 151 and the diffraction exit surface 152, so that the liquid can be effectively prevented from attaching to the diffraction incident surface 151 and the diffraction exit surface 152 after entering the laser projection module 10, and filling the diffraction structures in the diffraction micro-structure layer 154 on the body incident surface 1531 and the body exit surface 1532, so that double-sided protection is realized, and the situation that the laser projection module 10 is subjected to zero-order laser energy enhancement and then harms human eye safety is avoided.

Referring to fig. 6 and 7, the laser projection module 10 may further include a waterproof rubber ring 19 disposed between the limiting protrusion 123 and the diffractive optical element 15. The waterproof rubber ring 19 comprises a top surface 191 and a bottom surface 192 which are opposite to each other, wherein the top surface 191 abuts against the diffractive optical element 15, and the bottom surface 192 abuts against the limiting protrusion 123.

Specifically, referring to fig. 6 and 19, a waterproof rubber ring 19 is additionally arranged between the limiting protrusion 123 and the diffractive optical element 15, and the waterproof rubber ring 19 can form a waterproof sealing layer between the limiting protrusion 123 and the diffractive optical element 15. The waterproof rubber ring 19 is arranged on the limiting surface 1232, a closed environment is formed between the diffraction incident surface 151 of the diffractive optical element 15 and the limiting surface 1232, and it can be ensured that liquid cannot enter between the diffractive optical element 15 and the limiting protrusion 123, so that the problem that the liquid filled in the diffraction microstructure layer 154 generates zero-order laser energy to enhance and harm human eye safety is effectively avoided. It will be appreciated that the waterproof rubber ring 19 has good waterproof, wear-resistant and pressure-resistant functions. The waterproof rubber ring 19 can be a rubber ring, a silica gel rubber ring or other environment-friendly rubber rings.

Referring to fig. 7, in some embodiments, the limiting protrusion 123 may also be formed on the top of the lens barrel 12, specifically, the limiting surface 1232 of the limiting protrusion 123 may coincide with the first surface 124, and when the diffractive optical element 15 is mounted on the limiting protrusion 123, the diffractive optical element 15 is combined with the first surface 124. An airtight environment is formed between the diffraction incident surface 151 and the first surface 124 of the diffractive optical element 15, and it can also be ensured that liquid cannot enter between the diffractive optical element 15 and the limiting protrusion 123, so that the problem that the liquid filled with the diffractive microstructure layer 154 generates zero-order laser energy to enhance and harm human eye safety is effectively avoided.

Referring to fig. 6 and 7, the limiting protrusion 123 is provided with an annular accommodating groove 1233, and the waterproof rubber ring 19 is accommodated in the accommodating groove 1233.

The annular housing groove 1233 may be disposed on the position-limiting protrusion 123 in different manners. Referring to fig. 6, in some embodiments, the annular accommodating groove 1233 is disposed between the lens barrel 12, the diffractive optical element 15 and the limiting protrusion 123, the accommodating groove 1233 is disposed on the limiting surface 1232, and a side surface of the annular accommodating groove 1233 abuts against the barrel sidewall 122, so as to form a sealed environment between the lens barrel 12, the diffractive optical element 15 and the limiting protrusion 123, and once the laser projection module 10 is fed with liquid, the accommodating groove 1233 can serve as a first waterproof layer of the liquid-filled diffractive microstructure layer 154, so as to prevent the liquid-filled diffractive microstructure layer 154 from enhancing the energy of the zero-order laser, which may harm human eyes. Referring to fig. 7, an annular accommodating groove 1233 may be further disposed between the diffractive optical element 15 and the limiting protrusion 123, and the annular accommodating groove 1233 is located at a middle position of the first surface 124 of the limiting protrusion 123, specifically, the accommodating groove 1233 may be formed on the first surface 124, an adhesive may be disposed in the accommodating groove 1233 to adhere the diffractive optical element 15 to the first surface 124, and the waterproof rubber ring 19 may be formed after the adhesive is cured. At this time, the protective ceiling wall 161 abuts against the diffractive optical element 15, and the protective ceiling wall 161 and the stopper projection 123 sandwich the diffractive optical element 15. Thus, the lens barrel 12 has a simple structure, and the diffractive optical element 15 is easily attached to the stopper projection 123. Here, the annular housing groove 1233 may be a square ring shape, a circular ring shape, or another shape of ring shape, and is not limited herein.

In some embodiments, the material of the diffractive optical element 15 includes Polycarbonate (PC).

It is understood that the rupture of the diffractive optical element 15 will cause the laser emitted from the laser projection module 10 to be directly emitted, which is similar to directly irradiating the human eye with a laser pen, and the direct vision for 1 second will exceed the safety standard of the human eye, and the human eye may be irreversibly damaged. The eye safety hazard created by the fracture of the diffractive optical element 15 is much more severe than the zero order enhancement of the diffractive optical element 15.

Specifically, the polycarbonate material is a nearly colorless glassy amorphous polymer, and has the advantages that ① has good optical property, high transparency and free dyeing property, light rays emitted by the light source 13 can be ensured to penetrate through the diffractive optical element 15 after being collimated by the collimating element 14, ② has high strength and elastic coefficient, high impact strength and wide use temperature range, the situation that the diffractive optical element 15 is cracked or scratched can be effectively prevented, ③ has low forming shrinkage and good dimensional stability, the installation of the diffractive optical element 15 can be firmer, and the structure of the laser projection module 10 is more stable.

Of course, in other embodiments, the diffractive optical element 15 may be made of glass, or may be made of composite plastic (such as PET), and is not limited herein.

Referring to fig. 3, the protective cover 16 is coupled to the lens barrel 12, the protective cover 16 is used for limiting the position of the diffractive optical element 15, and specifically, the protective cover 16 is used for preventing the diffractive optical element 15 from falling out of the lens barrel 12 after the coupling of the diffractive optical element 15 and the lens barrel 12 fails. Referring to fig. 5, the protective cover 16 includes a protective top wall 161 and a protective side wall 162.

Referring to fig. 8 and 9, the protective top wall 161 and the limiting protrusion 123 are respectively located on two opposite sides of the diffractive optical element 15, or the diffractive optical element 15 is located between the limiting protrusion 123 and the protective top wall 161, so that even if the combination of the diffractive optical element 15 and the limiting protrusion 123 fails, the diffractive optical element 15 cannot be separated due to the limiting effect of the protective top wall 161. The protective top wall 161 is provided with a light through hole 1611, the position of the light through hole 1611 corresponds to the diffractive optical element 15, and the laser emitted by the light source 13 sequentially passes through the light through hole 1231, the diffractive optical element 15 and the light through hole 1611 and then is emitted from the laser projection module 10. In the embodiment of the present application, the overall shape of the protection top wall 161 is a rounded square, and the light passing hole 1611 may be a regular polygon, a circle, a rectangle, an ellipse, a trapezoid, or the like. The aperture size of the light passing hole 1611 is smaller than at least one of the width or the length of the diffractive optical element 15 to confine the diffractive optical element 15 between the protective top wall 161 and the stopper protrusion 123. In the embodiment shown in fig. 6, when the protective cover 16 is combined with the lens barrel 12, the protective top wall 161 is abutted against the first surface 124, and further, the protective top wall 161 may be combined with the first surface 124 by gluing or the like.

Referring to fig. 8, 9 and 20, the protection sidewall 162 extends from the periphery of the protection top wall 161, the protection cover 16 covers the lens barrel 12, and the protection sidewall 162 is fixedly connected to the lens barrel sidewall 122. The protective sidewall 162 is opened with a fixing hole 1622, and when the protective cover 16 covers the lens barrel 12, the fixing protrusion 127 extends into the fixing hole 1622. Specifically, the position where the fixing hole 1622 is opened corresponds to the position of the fixing protrusion 127, the protection cover 16 has certain elasticity, when the protection cover 16 is covered on the lens barrel 12, the fixing protrusion 127 and the protection side wall 162 abut against each other, the fixing protrusion 127 props up the protection side wall 162, the protection side wall 162 is elastically deformed, when the protection cover is mounted in place, the fixing protrusion 127 extends into the fixing hole 1622, the fixing protrusion 127 does not prop up the protection side wall 162 any more, the protection side wall 162 is restored to the original shape, and the touch feedback and the sound feedback of "click" accompanied with the mounting in place are provided. It can be understood that after the protective cover 16 is covered on the lens barrel 12, under the condition that the protective side walls 162 are not expanded by applying an external force, the protective cover 16 can be covered on the lens barrel 12 all the time due to the limiting function of the fixing protrusions 127, so that the protective top wall 161 prevents the diffractive optical element 15 from being released from the lens barrel 12.

In summary, in the electronic device 1000 according to the embodiment of the present disclosure, the diffractive optical element 15 is located between the limiting protrusion 123 and the protective top wall 161, and the fixing protrusion 127 can extend into the fixing hole 1622 to fixedly connect the protective cover 16 and the lens barrel 12, so that the diffractive optical element 15 cannot fall off along the light emitting direction, thereby preventing the laser from being emitted without passing through the diffractive optical element 15, protecting the user, and improving the safety.

Referring to fig. 9 and 20, in some embodiments, the protection sidewall 162 includes a plurality of protection sub-sidewalls 1621, and the protection sub-sidewalls 1621 are connected end to end. At least two protection sub-side walls 1621 are formed with fixing holes 1622, the number of fixing protrusions 127 is the same as the number of fixing holes 1622, and the positions of the fixing protrusions are corresponding, and each fixing protrusion 127 extends into the corresponding fixing hole 1622. Thus, the fixing protrusions 127 are matched with the fixing holes 1622, so that the protective cover 16 is not easily separated from the lens barrel 12 under the action of external force, and the reliability of covering the lens barrel 12 with the protective cover 16 is improved. Specifically, at least two opposite protection sub-side walls 1621 are formed with fixing holes 1622, and correspondingly, at least two opposite positions of the barrel side wall 122 are formed with fixing protrusions 127. Thus, if the protection side wall 162 needs to be stretched to take out the protection cover 16, at least two opposite protection sub side walls 1621 need to be stretched to two sides, that is, at least pulling force needs to be applied from two sides, so as to avoid the situation that the protection side wall 162 deforms under the action of the pulling force at one side to cause the matching failure of the fixing protrusion 127 and the fixing hole 1622, and further improve the reliability of the protection cover 16 covering the lens barrel 12.

Referring to fig. 9, in some embodiments, the fixing protrusion 127 is formed with a guiding inclined surface 1271, and the guiding inclined surface 1271 is gradually away from the barrel sidewall 122 along the direction in which the protective cover 16 is inserted into the barrel 12. The protective cover 16 covers the lens barrel 12, and the protective sidewall 162 abuts against the guiding inclined surface 1271. Since the guide slope 1271 is inclined with respect to the barrel side wall 122, in the process of abutting the protection side wall 162 against the guide slope 1271, the abutting force of the guide slope 1271 on the protection side wall 162 gradually and continuously increases, the deformation amount of the protection side wall 162 also continuously increases, and the protection cover 16 is easily covered in the barrel 12.

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 (12)

1. A laser projection module, comprising:

a light source for emitting laser light;

a collimating element to collimate the laser light; and

the diffraction optical element is used for diffracting the laser collimated by the collimation element to form a laser pattern, and a hydrophobic layer is arranged on the diffraction optical element.

2. The laser projection module of claim 1, wherein the diffractive optical element comprises opposing diffractive entrance and exit surfaces opposite the collimating element, and the hydrophobic layer is formed on the diffractive entrance and/or exit surface.

3. The laser projection module of claim 2, wherein the diffractive optical element comprises a light-transmissive diffractive body and a diffractive microstructure layer formed on the diffractive body, the diffractive body comprises a body incident surface and a body exit surface which are opposite to each other, the body incident surface corresponds to the diffractive incident surface, the body exit surface corresponds to the diffractive exit surface, the diffractive microstructure layer is formed on the body incident surface, and the hydrophobic layer is formed on the diffractive incident surface.

4. The laser projection module of claim 2, wherein the diffractive optical element comprises a light-transmissive diffractive body and a diffractive microstructure layer formed on the diffractive body, the diffractive body comprises a body incident surface and a body exit surface which are opposite to each other, the body incident surface corresponds to the diffractive incident surface, the body exit surface corresponds to the diffractive exit surface, the diffractive microstructure layer is formed on the body exit surface, and the hydrophobic layer is formed on the diffractive exit surface.

5. The laser projection module of claim 1, further comprising a barrel, the barrel comprising a barrel sidewall and a limiting protrusion protruding inward from the barrel sidewall; the laser projection module is characterized in that the laser projection module further comprises a waterproof rubber ring arranged between the limiting protrusion and the diffraction optical element, the waterproof rubber ring comprises a top surface and a bottom surface which are back to back, the top surface is abutted against the diffraction optical element, and the bottom surface is abutted against the limiting protrusion.

6. The laser projection module as claimed in claim 5, wherein the limiting protrusion defines an annular receiving groove, and the waterproof rubber ring is received in the receiving groove.

7. The laser projection module of claim 1, wherein the diffractive optical element comprises polycarbonate.

8. The laser projection module of claim 1, further comprising a barrel and a protective cover, wherein the barrel comprises a barrel sidewall, a limiting protrusion protruding inward from the barrel sidewall, and a fixing protrusion protruding outward from the barrel sidewall, and the diffractive optical element is mounted on the limiting protrusion; the protective cover comprises a protective top wall and a protective side wall extending from the protective top wall, the protective top wall is provided with a light through hole, the light through hole corresponds to the diffractive optical element, the protective side wall is provided with a fixing hole, the protective cover covers the lens barrel, the fixing protrusion extends into the fixing hole, and the diffractive optical element is located between the limiting protrusion and the protective top wall.

9. The laser projection module of claim 8, wherein the protection sidewalls include a plurality of protection sub-sidewalls connected end to end in sequence, at least two protection sub-sidewalls are formed with the fixing holes, the number of the fixing protrusions is the same as the number of the fixing holes, and the fixing protrusions are corresponding in position, and each fixing protrusion extends into the corresponding fixing hole; the fixing holes are formed on at least two opposite side walls of the protector.

10. The laser projection module of claim 8, wherein the fixing protrusion forms a guiding inclined surface, the guiding inclined surface is gradually away from the side wall of the lens barrel along a direction in which the protection cover is inserted into the lens barrel, and the protection side wall is abutted against the guiding inclined surface in a process in which the protection cover is covered on the lens barrel.

11. A depth camera, comprising:

the laser projection module of any of claims 1-10;

the image collector is used for collecting the laser patterns projected into the target space after passing through the diffractive optical element; and

and the processor is respectively connected with the laser projection module and the image collector and is used for processing the laser pattern to obtain a depth image.

12. An electronic device, comprising:

a housing; and

the depth camera of claim 11, in combination with the housing.

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