Photonic crystal surface-emitting laser device and optical system

Abstract

The application provides a photonic crystal surface emitting laser device, comprising: a substrate; a light emitting layer on one surface of the substrate, for generating photons under the driving of a driving signal; a photonic crystal layer on one side of the light emitting layer away from the substrate, for generating Bragg diffraction oscillation in the photonic crystal layer when the photons are incident to the photonic crystal layer, so as to generate laser; and a super-hap interface on one side of the substrate away from the photonic crystal layer, the super-hap interface comprising a base and a plurality of column bodies arranged between one surface of the base, shapes and / or sizes of at least two column bodies are different, the super-hap interface is used for receiving the laser, and the laser is emitted after diffraction, shapes and sizes of the column bodies are used for controlling an emission angle of the laser. The application also provides an optical system.

Description

Technical Field

[0001] This application relates to the field of laser detection technology, and in particular to a photonic crystal surface-emitting laser device and optical system. Background Technology

[0002] Photonic crystal surface-emitting laser (PCSEL) devices have advantages such as excellent beam quality, small size, low power consumption, easy integration, and high reliability, and are widely used in scanning LiDAR systems.

[0003] Existing LiDAR typically requires a motorized spinning scanner or a MEMS scanner to scan the laser beam. However, these structures are not conducive to controlling the size of the LiDAR. The photonic crystal surface-emitting laser device in LiDAR includes a diffraction grating to control the laser emission angle. However, traditional diffraction gratings consist of multiple periodically repeating, structurally identical diffraction units, providing only single control over the laser beam emission angle. The emission angle range is limited by grating fabrication processes, and higher-order diffraction effects cannot be eliminated, resulting in multiple symmetrically distributed laser spots, which is detrimental to beam scanning.

[0004] Therefore, the existing PCSEL urgently needs improvement. Summary of the Invention

[0005] The first aspect of this application provides a photonic crystal surface-emitting laser device, comprising: substrate; A light-emitting layer, located on a surface of the substrate, is used to generate photons under the drive signal. A photonic crystal layer, located on the side of the light-emitting layer away from the substrate, wherein when photons are incident on the photonic crystal layer, Bragg diffraction oscillations are generated in the photonic crystal layer to generate laser light; and A meta-interface is located on the side of the substrate away from the photonic crystal layer. The meta-interface includes a substrate and a plurality of pillars formed on a surface of the substrate at intervals. At least two of the pillars have different shapes and / or sizes. The meta-interface is used to receive the laser and diffract the laser before emitting it.

[0006] A second aspect of this application provides an optical system, comprising: Multiple photonic crystal surface-emitting laser devices, each of which is as described above; and A control device, electrically connected to the plurality of photonic crystal surface-emitting laser devices, is used to output drive signals to control the plurality of photonic crystal surface-emitting laser devices to turn on or off.

[0007] The aforementioned photonic crystal surface-emitting laser device and optical system include a meta-interface. The meta-interface includes a substrate formed on a surface of which a plurality of pillars are spaced apart. At least two of the pillars have different shapes and / or sizes. The meta-interface receives the laser light, diffracts it, and then emits it. By setting the shape, size, and number of the multiple pillars, the desired laser emission angle can be obtained, thereby controlling the number and size of the laser spot. In other words, the photonic crystal surface-emitting laser device and optical system of this embodiment, through the meta-interface, can not only deflect the laser light but also shape it, facilitating diversified control of the laser. Attached Figure Description

[0008] Figure 1 This is a schematic diagram of the module structure of the optical system in the embodiments of this application.

[0009] Figure 2 for Figure 1 A schematic diagram of the planar structure of a medium-photon crystal surface-emitting laser device.

[0010] Figure 3 for Figure 2 A schematic diagram of the cross-sectional structure of a medium-photon crystal surface-emitting laser device along line III-III.

[0011] Figure 4 for Figure 3 A schematic diagram of the planar structure of the photonic crystal layer.

[0012] Figure 5 This is a schematic diagram of the planar structure of the photonic crystal layer of a photonic crystal surface-emitting laser device in a modified embodiment of this application.

[0013] Figure 6 for Figure 3 A schematic diagram of the three-dimensional structure of the Chinese Super League interface.

[0014] Figure 7 This is a three-dimensional structural diagram of a diffraction unit in different meta-interfaces in other embodiments of this application.

[0015] Figure 8 For laser passing through Figure 7 A schematic diagram of the exit angle distribution after diffraction by the middle diffraction unit.

[0016] Figure 9 This is a three-dimensional structural diagram of a column in a super-interface of another embodiment of this application.

[0017] Explanation of main component symbols The following detailed description, in conjunction with the accompanying drawings, will further illustrate this application. Detailed Implementation

[0018] Please see Figure 1 The optical system 100 of this application includes multiple photonic crystal surface-emitting laser devices 1. The optical system 100 can be a facial recognition sensing device, a lidar, etc., and can be applied to various consumer electronic devices such as smartphones, augmented reality (AR) glasses, and virtual reality (VR) glasses. It can also be applied to automobiles, home or medical equipment, and unmanned vehicles used in smart factories and automated warehouses. When the photonic crystal surface-emitting laser device 1 is applied in the above-mentioned optical systems 100, it is used to emit lasers according to a driving signal to enable the optical system 100 to achieve functions such as three-dimensional image sensing and flight ranging.

[0019] The optical system 100 also includes a control device 2 electrically connected to each photonic crystal surface-emitting laser device 1. The control device 2 is used to output drive signals to each photonic crystal surface-emitting laser device 1. In this embodiment, the control device 2 may be a chip, a chip assembly, a control motherboard, etc. Multiple photonic crystal surface-emitting laser devices 1 are arranged in a laser emission array, and each photonic crystal surface-emitting laser device 1 is independently controlled by the control device 2 to be in an on or off state. Each photonic crystal surface-emitting laser device 1 emits laser light when it is in the on state and does not emit laser light when it is in the off state. In this laser emission array, at least two photonic crystal surface-emitting laser devices 1 emit laser light in different directions.

[0020] During a working period, the control device 2 controls one or more photonic crystal surface-emitting laser devices 1 to be turned on, depending on the direction, distance, size, etc. of the object to be detected. By changing the working state (on or off) of each photonic crystal surface-emitting laser device 1 in different working periods, the direction and shape of the laser emitted by the laser emission array in different working periods can be changed.

[0021] Please refer to the following: Figure 2 and Figure 3 The photonic crystal surface-emitting laser device 1 includes a substrate 10, a buffer layer 11, a first cladding layer 12, a light-emitting layer 13, and a photonic crystal layer 14 stacked sequentially.

[0022] The substrate 10 is an insulating substrate used to support and grow the buffer layer 11, the first cladding layer 12, the light-emitting layer 13, and the photonic crystal layer 14. The material of the substrate 10 can be n-type gallium arsenide. In this application, the material of the buffer layer 11 can be n-type gallium arsenide.

[0023] The light-emitting layer 13 includes multiple quantum well light-emitting layers 131 and multiple energy barrier layers 132. The multiple quantum well light-emitting layers 131 and multiple energy barrier layers 132 are stacked alternately. That is, the quantum well light-emitting layers 131 and energy barrier layers 132 are arranged alternately. In some embodiments of this application, the light-emitting layer 13 includes three to five quantum well light-emitting layers 131 and four to six energy barrier layers 132 stacked alternately. In this embodiment, the light-emitting layer 13 includes three quantum well light-emitting layers 131 and four energy barrier layers 132 stacked alternately. Each quantum well light-emitting layer 131 is made of indium gallium arsenide, and each energy barrier layer 132 is made of gallium arsenide. In other embodiments, the quantum well light-emitting layer 131 may also be aluminum gallium indium arsenide or indium gallium arsenide phosphide, and the energy barrier layer 132 may also be aluminum gallium arsenide or aluminum gallium indium arsenide.

[0024] The light-emitting layer 13 is used to generate photons under the drive signal. The photons generated by the light-emitting layer 13 propagate in all directions. The photons that propagate into the photonic crystal layer 14 generate Bragg diffraction oscillations in the photonic crystal layer 14 until the photonic crystal surface-emitting laser device 1 reaches a gain-loss balance state, thus generating laser light. In this embodiment, the laser wavelength emitted by the photonic crystal surface-emitting laser device 1 is 905 to 1550 nm (inclusive).

[0025] The photonic crystal layer 14 includes a stacked ohmic contact layer 141 and a second cladding layer 142, with the second cladding layer 142 located between the ohmic contact layer 141 and the light-emitting layer 13. In this embodiment, the ohmic contact layer 141 is made of p-type gallium arsenide. In other embodiments, the ohmic contact layer 141 may also be indium phosphide or indium gallium arsenide phosphide.

[0026] In this embodiment, the first cladding layer 12 is made of n-type aluminum gallium arsenide, and the second cladding layer 142 is made of p-type aluminum gallium arsenide. The first cladding layer 12 and the second cladding layer 142 are used to lock the photons emitted by the light-emitting layer 13, reducing the propagation of photons towards the photonic crystal layer 14. In other embodiments, the first cladding layer 12 and the second cladding layer 142 may also be made of indium aluminum arsenide, indium phosphide, or gallium arsenide phosphide.

[0027] Please see Figure 4 The photonic crystal layer 14 includes a first photonic crystal region 143 and a second photonic crystal region 144 surrounding the first photonic crystal region 143. When a photon is incident on the first photonic crystal region 143, Bragg diffraction oscillations are generated in the first photonic crystal region 143 to generate laser light. The second photonic crystal region 144 is used to reflect the received photons back to the first photonic crystal region 143 to reduce photon loss and improve the luminous efficiency of the photonic crystal surface-emitting laser device 1.

[0028] The first photonic crystal region 143 has a plurality of spaced-apart first through-holes 145, and the second photonic crystal region 144 has a plurality of spaced-apart second through-holes 146. Each first through-hole 145 penetrates the ohmic contact layer 141 and the second cladding layer 142, and each second through-hole 146 penetrates the ohmic contact layer 141 and the second cladding layer 142. All the first through-holes 145 and the second through-holes 146 are circular. All the first through-holes 145 have the same diameter, and all the second through-holes 146 have the same diameter. The diameter of the first through-hole 145 is larger than the diameter of the second through-hole 146. The energy position of a selected mode at the reciprocal space Γ point of the first photonic crystal region 143 is not aligned with the energy position of the same mode in the second photonic crystal region 144. Therefore, the resonant wavelength of the first photonic crystal region 143 can fall within the band gap of the second photonic crystal region 144, allowing the second photonic crystal region 144 to function as a horizontal reflector, reflecting photons back to the first photonic crystal region 143 to oscillate and generate laser light. In other embodiments, the first through-hole 145 and the second through-hole 146 can also be elliptical, triangular, quadrangular, "L"-shaped, "V"-shaped, double-hole, etc. (In this application, the shapes of the first through-hole 145 and the second through-hole 146 are respectively the opening shapes of the first through-hole 145 and the second through-hole 146 on the photonic crystal layer 14).

[0029] The region in which the photonic crystal surface-emitting laser device 1 can emit laser light is defined as the light-emitting region S. In this embodiment, the region where the first photonic crystal region 143 is located is the light-emitting region S.

[0030] Firstly, the smaller the area occupied by the first photonic crystal region 143, the smaller the driving signal threshold, that is, the smaller the current threshold required to drive the photonic crystal surface-emitting laser device 1 to emit laser. The smaller the current threshold, the shorter the time required to reach the current threshold, which is beneficial to improving the operating speed of the photonic crystal surface-emitting laser device 1.

[0031] Secondly, the smaller the area occupied by the first photonic crystal region 143, the smaller the emitting area of ​​the photonic crystal surface-emitting laser device 1. The smaller the emitting area of ​​a single photonic crystal surface-emitting laser device 1, the more photonic crystal surface-emitting laser devices 1 can be accommodated in a laser emitting array of the same area. The more photonic crystal surface-emitting laser devices 1 there are in the laser emitting array, the more diverse the direction and shape of the laser emitted by the laser emitting array.

[0032] Therefore, in this embodiment, by setting the photonic crystal layer 14 to include a first photonic crystal region 143 and a second photonic crystal region 144, and emitting laser light from the first photonic crystal region 143, it is beneficial to reduce the area of ​​the light-emitting region S of the photonic crystal surface-emitting laser device 1, thereby improving the operating speed of the photonic crystal surface-emitting laser device 1, and also making the direction and shape of the laser emitted by the laser emitting array used in the photonic crystal surface-emitting laser device 1 more diverse.

[0033] Depend on Figure 4 As can be seen, in this embodiment, the first photonic crystal region 143 is a rectangle, and the second photonic crystal region 144 is a rectangular frame surrounding the first photonic crystal region 143. Please refer to... Figure 5 In one modified embodiment of this application, the planar structure of the first photonic crystal region 143 is hexagonal, and the planar structure of the second photonic crystal region 144 is a hexagonal frame surrounding the first photonic crystal region 143. In other embodiments, the first photonic crystal region 143 may also be circular, and the second photonic crystal region 144 may be annular (in this application, the shapes of the first photonic crystal region 143 and the second photonic crystal region 144 are the shapes of the orthographic projections of the first photonic crystal region 143 and the second photonic crystal region 144 onto the substrate 10).

[0034] The shape of the first photonic crystal region 143 depends on the lattice type of the photonic crystal material in the photonic crystal layer 14. For example, when the lattice type of the photonic crystal material is a triangular lattice or a honeycomb lattice, the first photonic crystal region 143 is hexagonal; when the lattice type of the photonic crystal material is a square lattice, the first photonic crystal region 143 is quadrilateral (or rectangular).

[0035] Please continue reading. Figure 3 In this embodiment, the photonic crystal surface-emitting laser device 1 further includes a meta-interface 15. The meta-interface 15 is located on the surface of the substrate 10 away from the photonic crystal layer 14. The laser generated by the photonic crystal layer 14 is diffracted by the meta-interface 15 and exits from the side of the meta-interface 15 away from the photonic crystal layer 14.

[0036] The photonic crystal layer 14 and the metasurface 15 are positioned opposite each other. That is, the orthographic projection of the photonic crystal layer 14 onto the light-emitting layer 13 at least partially overlaps with the orthographic projection of the metasurface 15 onto the light-emitting layer 13. In this embodiment, the orthographic projection of the photonic crystal layer 14 onto the light-emitting layer 13 completely overlaps with the orthographic projection of the metasurface 15 onto the light-emitting layer 13. In other embodiments, the orthographic projection of the metasurface 15 onto the light-emitting layer 13 may completely cover the orthographic projection of the photonic crystal layer 14 onto the light-emitting layer 13. This is beneficial for maximizing the amount of laser light generated by the photonic crystal layer 14 that can be incident on the metasurface 15, thereby improving laser utilization.

[0037] Please refer to the following: Figure 6 The super-interface 15 includes a substrate 151 and a plurality of spaced-apart pillars 152 protruding from a surface of the substrate 151. Figure 2 The structure of column 152 in the plan view is for illustrative purposes only. For the specific structure of column 152, please refer to [the provided text]. Figure 6 (For reference only). The surface of the substrate 151, which is disposed opposite to the surface on which the pillars 152 are formed, is in direct contact with the surface of the substrate 10. The substrate 151 and the pillars 152 are made of the same material and are integrally formed. Each pillar 152 is formed by etching a substrate including the substrate 151. In this embodiment, the material of the super-interface 15 is the same as that of the substrate 10.

[0038] Each column 152 is a cylinder. In some embodiments, the spacing between each column 152 is the same, that is, the spacing between any two adjacent columns 152 is the same. In other embodiments, the spacing between any two adjacent columns 152 is not entirely the same. That is, some adjacent columns 152 have different spacings, some adjacent columns 152 have the same spacing, or all adjacent columns 152 have different spacings. In still other embodiments, the diameter and / or height of each column 152 is different. The plurality of columns 152 on the substrate 151 are divided into a plurality of diffraction units 150, each diffraction unit 150 comprising a plurality of adjacently arranged columns 152. Each diffraction unit 150 is used to diffract the received laser light.

[0039] Figure 7 Figures (a)-(c) illustrate the structures of several different diffraction units 150 in other embodiments of this application. Figure 8 The laser was shown Figure 7 The emission direction (or emission angle, where the direction perpendicular to the metasurface 15 is taken as 0°) after diffraction by various diffraction units 150. It can be seen that by changing the size (including diameter, height, etc.), shape and number of each cylinder in each diffraction unit 150, the emission direction of the laser after diffraction and emission by the metasurface 15 can be changed.

[0040] Furthermore, since the metasurface 15 can change the emission direction of the laser, when the metasurface 15 controls the laser to be concentrated in a certain direction, it is equivalent to forming a converging effect on the laser. In some embodiments, through the converging effect of the metasurface 15 on the laser, the laser emitted from the metasurface 15 can form a single spot or multiple spots. Depending on the degree of laser convergence, the size of the formed spot can also be controlled. Therefore, the metasurface 15 in this embodiment can also change the number of laser spots and the size of the formed spots by changing the size (including diameter, height, etc.), shape, and number of each column in each diffraction unit 150.

[0041] In other embodiments, each column 152 may be a column of other shapes. For example, Figure 9 The elliptical cylinder shown in Figure (a) Figure 9 The quadrangular prism shown in Figure (b) Figure 9 The triangular prism shown in Figures (c) and (d) Figure 9 The "L"-shaped cylinder shown in Figure (e) Figure 9 The “V” shaped column, “+” shaped column or “C” shaped column shown in Figure (f) (the shape of the column 152 described in this application is the shape of the column 152 projected onto the base 151).

[0042] In this embodiment, the photonic crystal surface-emitting laser device 1 has a flip-chip structure. After growing a buffer layer 11, a first cladding layer 12, a light-emitting layer 13, and a photonic crystal layer 14 on one surface of a substrate 10, the photonic crystal surface-emitting laser device 1 is inverted and mounted on a flip-chip substrate 200. A meta-interface 15 is formed on the other opposite surface of the substrate 10. In this embodiment, the substrate 10 is thinned before the meta-interface 15 is formed. In some embodiments, the thickness of the substrate 10 after the thinning treatment is 10% to 90% of that before the thinning treatment, preferably 20% to 70%. Thinning the substrate 10 helps maintain heat dissipation. Furthermore, since the laser needs to pass through the substrate 10 before being emitted, thinning the substrate 10 also helps reduce the absorption of the laser by the substrate 10 and reduce laser loss.

[0043] Please refer to the following: Figure 3 In this embodiment, the photonic crystal surface-emitting laser device 1 further includes a first transparent conductive layer 161 and a second transparent conductive layer 162. The first transparent conductive layer 161 is located on the surface of the metasurface 15 away from the photonic crystal layer 14, and the second transparent conductive layer 162 is located on the surface of the photonic crystal layer 14 away from the substrate 10. Both the first transparent conductive layer 161 and the second transparent conductive layer 162 are indium tin oxide (ITO). The first transparent conductive layer 161 and the second transparent conductive layer 162 are used to diffuse current, making the current distribution more uniform.

[0044] In this embodiment, the first transparent conductive layer 161 covers the surface of the substrate 151 where the pillars 152 are formed and fills the space between the pillars 152 in the super-interface 15. The thickness of the first transparent conductive layer 161 is less than the height of each pillar 152, that is, the space between each pillar 152 is not completely filled by the first transparent conductive layer 161.

[0045] Therefore, when the laser light enters the meta-interface 15 from the photonic crystal layer 14, it needs to pass through two dielectric layers with different refractive indices. In this embodiment, the two dielectric layers with different refractive indices are defined as a first dielectric layer 153 and a second dielectric layer 154. The first dielectric layer 153 is a dielectric layer composed of each pillar 152 and a first transparent conductive layer 161. After passing through the first dielectric layer 153, the laser light has a first deflection angle α1. The second dielectric layer 154 is a dielectric layer composed of each pillar 152 and air. After passing through the second dielectric layer 154, the laser light has a second deflection angle α2. It can be seen that the laser light undergoes two angular deflections after passing through the two dielectric layers with different refractive indices. Therefore, the angle of the laser light finally emitted by the photonic crystal surface laser emission device 1 is the sum of the two angular deflections, which is α1 + α2.

[0046] Therefore, by providing a first transparent conductive layer 161, which partially fills the space between each pillar 152, it is beneficial to increase the deflection angle of the final emitted laser from the photonic crystal surface-emitting laser device 1, resulting in a larger deflection angle range for the final emitted laser. Consequently, when the photonic crystal surface-emitting laser device 1 is applied to the optical system 100, the optical system 100 has a larger detection range.

[0047] In this embodiment, the photonic crystal surface-emitting laser device 1 further includes a first electrode 171 and a second electrode 172. The first electrode 171 is located on the side of the substrate 10 away from the photonic crystal layer 14 and is in electrical contact with the first transparent conductive layer 161. The second electrode 172 is located on the surface of the second transparent conductive layer 162 away from the photonic crystal layer 14 and is in electrical contact with the second transparent conductive layer 162. The first electrode 171 and the second electrode 172 are used to be electrically connected to the control device 2 to receive the drive signal. The first electrode 171 and the second electrode 172 are metals, such as titanium (Ti), germanium (Ge), nickel (Ni), gold (Au), or platinum (Pt) and their alloys. In this embodiment, the first electrode 171 is an n-type electrode and the second electrode 172 is a p-type electrode.

[0048] When driving signals are applied to the first electrode 171 and the second electrode 172 respectively (the magnitudes of the driving signals applied to the first electrode 171 and the second electrode 172 are different), driving current is injected from the side of the photonic crystal layer 14 near the light-transmitting substrate 10. The light-emitting layer 13 generates photons under the drive of the driving current. When the photons generated by the light-emitting layer 13 propagate to the photonic crystal layer 14, Bragg diffraction oscillations are generated in the photonic crystal layer 14 until the photonic crystal surface-emitting laser device 1 reaches the gain and loss balance and generates laser light. The laser light is incident on the meta-interface 15 and after being diffracted by the meta-interface 15 with a specific structure, it is emitted by the meta-interface 15 in a specific shape and at a specific angle.

[0049] In this embodiment, the photonic crystal surface-emitting laser device 1 further includes an insulating layer 18. The insulating layer 18 may be silicon nitride (SiNx), silicon dioxide (SiO2), or polymethyl methacrylate (PMMA). The insulating layer 18 is located between the substrate 10 and the first electrode 171, and between the second electrode 172 and the photonic crystal layer 14. The insulating layer 18 is mainly disposed around the first electrode 171, the second electrode 172, the substrate 10, and the photonic crystal layer 14, and plays a protective role for each layer of materials in the photonic crystal surface-emitting laser device 1.

[0050] The photonic crystal surface-emitting laser device 1 and optical system 100 of this embodiment include a meta-interface 15. The meta-interface includes a substrate 151 and a plurality of pillars 152 spaced apart on a surface of the substrate 151. At least two pillars 152 have different shapes and / or sizes. The meta-interface 15 is used to receive laser light, diffract the laser light, and then emit it. By setting the shape, size, and number of the plurality of pillars 152, the desired laser emission angle can be obtained, thereby also controlling the number and size of the laser spot. That is, the photonic crystal surface-emitting laser device 1 and optical system 100 of this embodiment, through the meta-interface 15, can not only achieve laser deflection but also laser shaping, which is beneficial for achieving diversified control of the laser.

[0051] Those skilled in the art should recognize that the above embodiments are only used to illustrate this application and are not intended to limit this application. Any appropriate changes and variations made to the above embodiments within the essential spirit and scope of this application fall within the scope of protection claimed in this application.

Claims

1. A photonic crystal surface-emitting laser device, characterized in that, include: substrate; A light-emitting layer, located on a surface of the substrate, is used to generate photons under the drive signal. A photonic crystal layer, located on the side of the light-emitting layer away from the substrate, wherein when photons are incident on the photonic crystal layer, Bragg diffraction oscillations are generated in the photonic crystal layer to generate laser light; and A meta-interface is located on the side of the substrate away from the photonic crystal layer. The meta-interface includes a substrate and a plurality of pillars formed on a surface of the substrate at intervals. At least two of the pillars have different shapes and / or sizes. The meta-interface is used to receive the laser and diffract the laser before emitting it. The photonic crystal surface-emitting laser device further includes a first transparent conductive layer, which covers the surface of the substrate on which the plurality of pillars are formed and fills part of the space between the plurality of pillars.

2. The photonic crystal surface-emitting laser device as described in claim 1, characterized in that, The spacing between each adjacent column in the plurality of columns is equal; or The spacing between adjacent columns is not entirely equal.

3. The photonic crystal surface-emitting laser device as described in claim 1, characterized in that, The super-interface includes multiple diffraction units, and each diffraction unit includes one or more pillars among the multiple pillars; The shape and / or size of each of the pillars in each of the diffraction units are different.

4. The photonic crystal surface-emitting laser device as described in claim 1, characterized in that, The thickness of the first transparent conductive layer is less than the height of the plurality of pillars.

5. The photonic crystal surface-emitting laser device as described in claim 1, characterized in that, The photonic crystal layer includes a first photonic crystal region and a second photonic crystal region surrounding the first photonic crystal region; When a photon is incident on the photonic crystal layer, Bragg diffraction oscillations are generated in the first photonic crystal region, and the second photonic crystal region is used to reflect the received photon back to the first photonic crystal region.

6. The photonic crystal surface-emitting laser device as described in claim 5, characterized in that, The orthographic projection of the first photonic crystal region onto the substrate is a rectangle, and the orthographic projection of the second photonic crystal region onto the substrate is a rectangular frame surrounding the rectangle; or The orthographic projection of the first photonic crystal region onto the substrate is a hexagon, and the orthographic projection of the second photonic crystal region onto the substrate is a hexagonal frame surrounding the hexagon; or The first photonic crystal region is projected onto the substrate in the form of a circle, and the second photonic crystal region is projected onto the substrate in the form of an annulus surrounding the circle.

7. The photonic crystal surface-emitting laser device as described in claim 5, characterized in that, The first photonic crystal region has multiple first through holes, and the second photonic crystal region has multiple second through holes, wherein the multiple first through holes and the multiple second through holes are of different sizes.

8. The photonic crystal surface-emitting laser device as described in claim 1, characterized in that, The super-interface is made of the same material as the substrate.

9. The photonic crystal surface-emitting laser device as described in any one of claims 1 to 4, characterized in that, It also includes a second transparent conductive layer, which is located on the surface of the photonic crystal layer away from the substrate, for diffusing current.

10. An optical system, characterized in that, include: Multiple photonic crystal surface-emitting laser devices, each of which is described in any one of claims 1 to 9; and A control device, electrically connected to the plurality of photonic crystal surface-emitting laser devices, is used to output drive signals to control the plurality of photonic crystal surface-emitting laser devices to turn on or off.

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