Anti-reflective vertical cavity surface-emitting laser and chip

Abstract

An anti-reflective vertical-cavity surface-emitting laser and chip, wherein the laser comprises an active region (30) including at least five active layers (310) and tunnel junctions (330) located between the active layers (310), and Bragg reflective layers (10) located on opposite sides of the active region (30), wherein an anti-reflective storage resonator (40) is provided between the active region (30) and at least one of the Bragg reflective layers (10), and the anti-reflective storage resonator (40) is configured to increase the optical field intensity peak value to a value higher than the optical field intensity peak value of the active region (30) and to store optical field energy, and a current-constricting layer (320) is provided within or near the outside of the active region (30), the optical aperture of the laser is located in the current injection region of the current-constricting layer (320), and the output laser is a single transverse-mode laser.

Description

Technical Field

[0001] This application claims the priority of the US provisional application "Antireflective vertical-cavity surface-emitting laser" with provisional patent application serial number 63 / 607,776 filed on December 8, 2023, and the priority of the Chinese patent application with application number 202410506937.X filed with the Chinese Patent Office on April 25, 2024. The entire content of the above applications is incorporated herein by reference.

[0002] Embodiments of this application relate to the technical field of semiconductor laser devices, for example, antireflective vertical-cavity surface-emitting lasers and chips.

Background Art

[0003] Multi-junction vertical-cavity surface-emitting lasers (VCSELs) are becoming increasingly popular in automotive lidar. However, the divergence angle of conventional VCSELs is generally 20° - 30°, which is quite large for many mid- to long-range scanning lidars.

[0004] Conventional methods for reducing the divergence angle of a VCSEL beam involve extending the length of the resonator using a resonator extension layer, thereby reducing the contrast in effective refractive index between the inside and outside of the VCSEL's optical aperture and suppressing the generation of higher-order transverse modes. However, increasing the VCSEL's resonator length also reduces the spacing between the laser's longitudinal modes, resulting in the appearance of multiple longitudinal modes, or multiple spectral peaks, in the VCSEL's emission spectrum. Of these multiple spectral peaks, in addition to the designed laser oscillation wavelength, other undesirable spectral peaks may appear on one or both sides of the designed laser oscillation wavelength; these undesirable spectral peaks are usually called side modes. The appearance of side modes can lead to potential problems such as reduced efficiency and crosstalk, for example, because these side modes cannot be identified on the receiving side of a laser radar. Other methods for reducing the divergence angle include the use of high-index-contrast gratings (HCG), slow-light amplifiers, microlens integration, or different types of current constriction, such as ion implantation and embedded tunnel junctions. However, each of these methods has its own unique challenges, such as being complex to manufacture, high in cost, having low power density, and making it difficult to achieve a uniform light emission pattern. [Overview of the project]

[0005] In the embodiments of this application, an anti-reflective vertical cavity surface-emitting laser and chip are provided that significantly reduce the divergence angle, increase brightness and spectral brightness, maintain single longitudinal mode laser oscillation, and avoid problems such as complex manufacturing, high cost, and low power density.

[0006] In embodiments of the present application, an anti-reflective vertical-cavity surface-emitting laser is provided, comprising: a lower Bragg reflective layer; an active region located on one side of the lower Bragg reflective layer and including at least five active layers and tunnel junctions located between the active layers; an upper Bragg reflective layer located on the side of the active region away from the lower Bragg reflective layer; and an anti-reflective storage resonator located at at least one location between the lower Bragg reflective layer and the active region, and between the upper Bragg reflective layer and the active region, wherein the anti-reflective storage resonator increases the optical field intensity peak value to a value higher than the optical field intensity peak value of the active region and stores optical field energy. The present invention provides an anti-reflective vertical cavity surface-emitting laser, wherein a current-constricting layer is provided within or near the outside of the active region, the current-constricting layer comprises an oxide layer, the oxide layer is an epitaxial film layer in which the epitaxially grown Al component is higher than a preset value, an insulating aluminum oxide film layer is formed in the oxidized region outside thereof, a light-emitting region into which an active current is injected is formed in the unoxidized region, the optical aperture of the anti-reflective vertical cavity surface-emitting laser is located in the current injection region, and the laser output from the anti-reflective vertical cavity surface-emitting laser is a single transverse-mode laser.

[0007] According to another aspect of the present application, an anti-reflective vertical cavity surface-emitting laser chip is provided, comprising at least one laser array, the laser array comprising a plurality of anti-reflective vertical cavity surface-emitting lasers as described in any one of claims 1 to 12, the laser array being a regularly arranged array, or a randomly arranged array, or an array having a plurality of addressable sub-arrays. [Brief explanation of the drawing]

[0008] [Figure 1] This is a schematic diagram of the structure of an anti-reflective vertical cavity surface-emitting laser according to an embodiment of the present invention. [Figure 2] This is a schematic diagram of the structure of a vertical cavity surface-emitting laser with a cavity extension layer related to the technology. [Figure 3]Figure 2 shows a distant field view of a laser array with the structure shown, taken at a distance of 50 mm. [Figure 4] Figure 2 shows the optical field intensity distribution and refractive index distribution diagrams for the structure shown. [Figure 5] Figure 2 is a comparison of the array laser spectrum and the FP longitudinal mode reflection spectrum of a laser array with the structure shown in Figure 2 at different temperatures. [Figure 6] This is a schematic diagram of the structure of another anti-reflective vertical cavity surface-emitting laser according to an embodiment of the present application. [Figure 7] Figure 6 shows a distant field view of a laser array with the structure shown, taken at a distance of 50 mm. [Figure 8] Figure 6 shows the optical field intensity distribution and refractive index distribution diagrams for the structure shown. [Figure 9] Figure 6 is a comparison of the array laser spectrum and the FP longitudinal mode reflection spectrum of a laser array with the structure shown at different temperatures. [Figure 10] This is a comparison diagram of the change in light intensity between a vertical-cavity surface-emitting laser in related technologies and an anti-reflective vertical-cavity surface-emitting laser in the embodiment of this application. [Figure 11] ~ [Figure 15] This is a diagram illustrating the principle of constructing the electric field distribution in an anti-reflective vertical-cavity surface-emitting laser according to an embodiment of the present invention. [Figure 16] This figure shows a comparison of the relationship curve between the average M2 factor and the injection current, and the array near-field image and array far-field image, for a laser array having the structure shown in Figure 6 and a laser array having the structure shown in Figure 2, according to an embodiment of the present application. [Figure 17] Figure 6 is a comparison diagram of the various photoelectric characteristics of a laser array with the structure shown in Figure 6 and various other laser arrays in related technologies. [Figure 18] These are optical field intensity distribution diagrams and refractive index distribution diagrams for another anti-reflective vertical cavity surface-emitting laser according to an embodiment of the present application. [Figure 19] This diagram shows the relationship between the divergence angle and the phototrapping factor of the oxide layer in the embodiment of the present application. [Figure 20]This diagram shows the relationship between the divergence angle and the effective resonator length according to the embodiment of the present application. [Figure 21] This diagram shows the relationship between the laser array brightness, spectral width, and spectral brightness, respectively, and the phototrapping factor of the oxide layer in the embodiment of the present application. [Figure 22] This is a relationship curve diagram between the mean M2 factor and current density of AR-VCSEL arrays with different optical apertures according to an embodiment of the present application. [Figure 23] These are laser spectral diagrams of an AR-VCSEL with a 7-micron optical aperture according to an embodiment of the present application at different output powers. [Figure 24] This is a comparison diagram of measured near-field and far-field images at different output powers of an AR-VCSEL with a 7-micron optical aperture according to an embodiment of the present application. [Figure 25] This is a comparative diagram of luminance and unit effective area power between the AR-VCSEL according to the embodiment of the present application and other types of semiconductor lasers for laser radar applications. [Figure 26] This is a comparative diagram of spectral brightness and unit effective area power between the AR-VCSEL according to the embodiment of the present application and other types of semiconductor lasers for laser radar applications. [Figure 27] This is a schematic diagram of the structure of a rectangular laser array consisting of four rectangular AR-VCSELs according to an embodiment of the present application. [Figure 28] Figure 27 is a schematic diagram of a far-field image of the structure shown, measured with an injection current of 5.5A. [Figure 29] The laser spectral diagrams shown in Figure 27 were obtained by injecting a 5.5A injection current at different temperatures into the structure shown. [Figure 30] Figure 27 shows curve diagrams of various photoelectric properties of the structure shown. [Figure 31] This is a schematic diagram of the structure of a hexagonal laser array consisting of 37 hexagonal AR-VCSELs according to an embodiment of the present invention. [Figure 32] Figure 31 is a schematic diagram of a far-field image of the structure shown, measured with an injection current of 10A. [Figure 33] This is a laser spectrum diagram obtained by injecting a 10A injection current at different temperatures into the structure shown in Figure 31. [Figure 34] Figure 31 shows curve diagrams illustrating various photocurrent characteristics of the structure shown. [Figure 35] This is a comparison diagram of the photoelectric characteristics of various AR-VCSEL arrays according to embodiments of the present application and various high-power laser arrays related to related technologies. [Figure 36] This is a schematic diagram of the free-space lens setup used for measuring a single-emission laser spectrum according to an embodiment of the present invention. [Figure 37] This is a schematic diagram of the structure of the light source drive circuit according to an embodiment of the present invention. [Modes for carrying out the invention]

[0009] The technical proposal in the embodiments of this application will be described below with reference to the drawings of the embodiments of this application, but it goes without saying that the embodiments described are only a part of the embodiments of this application and not all of them. All other embodiments that a person skilled in the art could obtain based on the embodiments of this application without any creative work are all within the scope of protection of this application.

[0010] Furthermore, the terms "First," "Second," etc., in the specification and claims of this application, as well as in the drawings, are for distinguishing similar subjects and are not used to describe a specific order or priority. The data used in this manner is replaceable where appropriate, so it should be understood that the embodiments of this application described herein may be carried out in an order other than that illustrated or described herein. In addition, the terms "includes" and "has" and all variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or apparatus that includes a series of steps or units is not necessarily limited to those steps or units listed, and may include other steps or units that are not listed or are specific to those processes, methods, products or apparatus.

[0011] As with the background technology, VCSEL arrays have become the main light source for high-speed data communication and sensing due to their compactness, fast response, and high energy conversion efficiency. Laser radar systems equipped with VCSEL array solid-state light sources have been commercialized in autonomous vehicles. High-resolution laser radar light sources have many performance metrics, such as power, power density, divergence angle, beam quality, beam parameter product, spectral width, luminance, spectral luminance, wavelength, temperature stability, pulse width, energy conversion efficiency, switching speed, module size, and power per effective area. Luminance, i.e., unit solid angle, is defined by equation (1). The power density per TIFF2026517353000002.tif69 (unit: steradians, sr) is a composite of the first five indicators. In equation (1), JPEG2026517353000003.jpg624 represents brightness, JPEG2026517353000004.jpg634 is the power density, TIFF2026517353000005.tif69 is a solid angle, TIFF2026517353000006.tif65 represents the luminescence area.

[0012] The filename is JPEG2026517353000007.jpg11100. Furthermore, spectral brightness is, It is defined as JPEG2026517353000008.jpg11109, In formula (2), JPEG2026517353000009.jpg639 is spectral brightness, TIFF2026517353000010.tif68 is the spectral width, which is a combination of the first six indicators.

[0013] Brightness is particularly important for scanning LiDAR systems that utilize collimated laser beams. Higher brightness results in a longer detectable distance and higher angular resolution for scanning LiDAR systems. On the receiving side, narrow-pass filters are typically applied before the detector to achieve longer detection distances by obtaining a high signal-to-noise ratio. The system's signal-to-noise ratio is inversely proportional to the filter bandwidth; the smaller the filter bandwidth, the higher the system's signal-to-noise ratio. Traditionally, the bandwidth of optical filter elements covers the entire range of laser source wavelength shifts from -40°C to 125°C, as required by the Automotive Electronics Commission standards. However, if the wavelength shift temperature coefficient of the optical filter element is well matched to the laser source, the optical filter element bandwidth can be significantly narrowed. Furthermore, if the wavelength angular shift of the optical filter element can be minimized to a negligible degree, the optical filter element bandwidth can even approach the laser spectral width itself. In this case, spectral brightness becomes more important in evaluating the final ability of the laser source to achieve a high signal-to-noise ratio.

[0014] In the case of an array-type laser light source, the emission area TIFF2026517353000011.tif65 is defined as the area of ​​the smallest circle or rectangle enclosing all emitters. The solid angle is It can be represented as JPEG2026517353000012.jpg642, where, TIFF2026517353000013.tif65 is a divergent half-width character, If TIFF2026517353000014.tif65 is very small It can be approximated as TIFF2026517353000015.tif620. Denominator in equation (1) TIFF2026517353000016.tif612 (etendue, also called focusing rate) is preserved when the beam passes through any ideal collimating lens system. Only when none of the optical devices in the propagation process are ideal, TIFF2026517353000017.tif612 increases. Similarly, power can only be maintained or reduced by any optical losses during propagation. As a result, luminance and spectral luminance can only be maintained unchanged in an ideal, lossless lens system; otherwise, they decrease. Therefore, in addition to improving optical devices and increasing laser emission power, reducing the focusing efficiency of the original laser beam from the bare tip is crucial for achieving high luminance and high spectral luminance for distant objects.

[0015] Regarding the selection of light sources for LiDAR, there has been a long-standing debate between edge-emitting lasers (EELs) and VCSELs. EELs were introduced to LiDAR applications earlier than VCSELs because they typically generate significantly more power with a single laser than single-emitter VCSELs. However, VCSELs have recently become preferred. Compared to high-power Fabry-Perot (FP) EELs, VCSELs have a narrower spectral width (<2 nm) and better wavelength temperature-dependent stability (0.06–0.07 nm / °C). Over a wide temperature range of -40 to 125°C, VCSEL wavelengths drift by only 12 nm, allowing for narrower filter bandwidths even without filters to match this wavelength-temperature drift. Optical filter systems in some laser radars may be specifically designed to match the VCSEL's wavelength-temperature drift coefficient of 0.06–0.07 nm / °C. However, achieving the same temperature drift coefficient as the FP EEL (0.2-0.3 nm / °C) is extremely difficult, if not entirely impossible. On the other hand, EELs with improved wavelength stability (e.g., Distributed Feedback (DFB) lasers and Distributed Bragg Reflector (DBR) lasers) require carefully designed Bragg gratings and further manufacturing processes, such as electron beam lithography. Furthermore, while VCSELs can generate excellent circularly symmetric beams, EEL beam profiles are asymmetric. Finally, due to their inherent 2D array manufacturability, VCSELs have unparalleled advantages in 2D point cloud generation and chip-level optical integration, without requiring complex optical devices or complex packaging. These advantages have led many LiDAR manufacturers to adopt VCSEL arrays as light sources. However, compared to EELs, conventional VCSEL array designs still require higher power density, smaller divergence angles, and higher spectral brightness to compete with other LiDAR light sources.

[0016] The VCSEL power density is equivalent to that of a high-power EEL array, at 1000 W / mm². 2 There are several ways to improve performance to a certain level. First, for medium- and long-range LiDAR, the conditions for operation are nanosecond short pulses and low duty cycles. This generates relatively low average power and avoids overheating of the laser tip, thereby increasing the peak power of the laser. Also, VCSELs can use series or multi-junction structures. By connecting several PN junctions perpendicularly in series with the tunnel junction without increasing the light-emitting area, a slope efficiency (SE, in units of W / A) directly proportional to the number of PN junctions can be generated, which significantly improves power density. From an energy-saving perspective, if the required optical power output is constant, a series structure effectively reduces the input current by increasing the input voltage (this is not a problem in automobiles, but is more limited in consumer electronic products). Lower current reduces the waste heat from parasitic series resistance in the drive circuit, thus improving the energy conversion efficiency of the system. Leading companies in the VCSEL industry have now begun mass production of 5-7 junction VCSELs and are developing even more junctions. In addition to multi-junction designs, VCSEL power density may be further improved by increasing the effective light-emitting area (packing factor) of the entire VCSEL array region and increasing the operating current as long as the device lifetime allows, thereby improving energy conversion efficiency.

[0017] EELs may also employ a multi-junction structure. However, in order to avoid losses due to absorption of optical field energy, the tunnel junction must be placed at the minimum optical field between optical modes, and therefore its power density is limited by the necessary separation of the optical modes of each junction. Furthermore, there is a potential reliability problem of destructive optical damage (COD) when, for example, the spacing distance between PN junctions becomes too close. Typically, the spacing between junctions in an EEL reaches several microns and is observed as individual emitters in near-field imaging. Therefore, applying a multi-junction structure to an EEL does not increase its power density.

[0018] Since the power density of VCSELs is already sufficient to meet the requirements of LiDAR, reducing their beam divergence angle to obtain higher brightness has become a pressing need. A low beam divergence angle is typically associated with fewer higher-order modes and a narrower spectral width, thus doubling its impact on spectral brightness. The perfect divergence angle in D86 is defined as the angle obtained by extending the D86 beam width in the far field, where the D86 beam width is defined as the diameter of the circle containing 86% of the optical field energy centered on the centroid of the beam profile. The perfect D86 divergence angle of VCSELs based on an oxide layer (current-constricting layer) is generally 20° to 30°, which is quite large for many medium-to-long-range (>100 meter) scanning LiDARs. Due to stronger lateral optical confinement, multi-junction VCSELs with multiple oxide layers for current constriction may have larger divergence angles than single-junction VCSELs.

[0019] Reducing the number of oxide layers in a multi-junction VCSEL can lead to a loss of power conversion efficiency (PCE), otherwise requiring further current constriction, such as ion implantation. A conventional method for reducing the divergence angle of a VCSEL beam while maintaining efficiency is to reduce the effective refractive index contrast (Δn) between the inside and outside of the VCSEL's optical aperture by extending the length of the resonator using a resonator extension layer. This reduced refractive index contrast suppresses the generation of higher-order transverse modes. Therefore, the resonator extension layer effectively functions as a higher-order mode suppressor or "low-pass" mode filter. After filtering out higher-order mode beams exhibiting low beam quality (large M2 factor and large divergence angle), lower-order mode beams with small divergence angles dominate the laser modal. Other methods for reducing the divergence angle include the use of high-contrast gratings (HCG), slow-light optical amplifiers, microlens integration, or different types of current constriction, such as ion implantation and embedded tunnel junctions. However, many of these methods have their own unique challenges, such as being complex to manufacture, high in cost, having low power density, and making it difficult to achieve a uniform light emission pattern.

[0020] On the other hand, increasing the resonator length leads to new problems. Increasing the resonator length also reduces the spacing between the longitudinal modes of the laser, resulting in the appearance of multiple longitudinal modes, or multiple spectral peaks, in the emission spectrum of the VCSEL. Among these multiple spectral peaks, in addition to the designed laser oscillation wavelength, other undesirable spectral peaks may appear on one or both sides of the designed laser oscillation wavelength, and these undesirable spectral peaks are usually called side modes. The appearance of side modes can lead to potential problems such as an increase in the temperature drift coefficient of the light source, a decrease in temperature stability, and a decrease in efficiency or crosstalk due to the inability of the receiving side of a 3D sensor or laser radar to identify these side modes.

[0021] In view of the above, the embodiment of the present application provides an anti-reflective vertical cavity surface-emitting laser (AR-VCSEL), and Figure 1 is a schematic diagram of the structure of an anti-reflective vertical cavity surface-emitting laser according to the embodiment of the present application. Referring to Figure 1, the anti-reflective vertical cavity surface-emitting laser comprises a lower Bragg reflective layer 10, an active region 30 located on one side of the lower Bragg reflective layer 10 and including at least five active layers 310 and tunnel junctions 330 located between the active layers 310, an upper Bragg reflective layer 20 located on the side of the active region 30 away from the lower Bragg reflective layer 10, and an anti-reflective storage resonator 40 located at at least one location between the lower Bragg reflective layer 10 and the active region 30, and between the upper Bragg reflective layer 20 and the active region 30. 40 is configured to increase the optical field intensity peak value until it is higher than the optical field intensity peak value of the active region 30, and to accumulate optical field energy. Here, a current constriction layer 320 is provided inside or near the outside of the active region 30, and the current constriction layer 320 comprises an oxide layer, the oxide layer is an epitaxial film layer in which the epitaxially grown Al component is higher than a preset value, an insulating aluminum oxide film layer is formed in the oxidized region outside thereof, and an emission region into which an active current is injected is formed in the unoxidized region, the optical aperture of the anti-reflective vertical cavity surface-emitting laser is located in the current injection region (see the rectangular ring region of the rectangular AR-VCSEL in Figure 27), and the aperture value of the optical aperture (OA) is the laser quality factor (M) of the laser. 2 It is negatively correlated with the factor, the aperture value includes 7 μm, and the laser output from the anti-reflective vertical-cavity surface-emitting laser includes a 28.4 mW high-power single transverse-mode laser.

[0022] The anti-reflective vertical-cavity surface-emitting laser according to the embodiment of the present application is provided with an anti-reflective storage resonator at least one location between the multi-junction active region and the lower Bragg reflective layer, and between the multi-junction active region and the upper Bragg reflective layer. The anti-reflective storage resonator increases the optical field intensity peak value to a level higher than the optical field intensity peak value of the multi-junction active region and stores optical field energy. As a result, the optical field intensity of the transparent storage resonator is higher than that of the multi-junction active region, reducing the difference in effective refractive index between the inside and outside of the VCSEL emission hole, suppressing the generation of higher-order modes, and reducing the divergence angle. At the same time, by increasing the optical field intensity inside the anti-reflective storage resonator, the increase in resonator length can be reduced compared to the configuration in related technologies that lengthens the resonator length. This improves the problem of multiple longitudinal modes appearing in the emission spectrum of the VCSEL, and thereby enables the maintenance of single-longitudinal-mode laser oscillation while significantly reducing the divergence angle. Furthermore, it does not require the use of high-contrast gratings (HCG), slow-light amplifiers, microlens integration, or different types of current constriction, thus avoiding problems such as complex manufacturing, high cost, and low power density. The active region includes at least five active layers, which can increase brightness and spectral brightness. The size of the optical aperture OA and M 2 A clear correlation exists between the factors. The aperture value of the optical aperture OA is 7 μm for 5 or more junction AR-VCSEL single emitters, M 2 The factor is close to 1, making it possible to realize a high-power single transverse-mode laser of 28.4 mW.

[0023] Preferably, the anti-reflective vertical cavity surface-emitting laser according to the embodiment of the present application has an injection current density of 10 kA / cm². 2 It operates under the conditions that the value is greater than or equal to 4W / A, the slope efficiency is greater than 4W / A, and the D86 full angle of the far field divergence is 19° or less.

[0024] For fair comparison, the embodiments of this application performed tests on the far-field divergence angle, optical field distribution within the laser, and spectrum at different temperatures for VCSEL arrays in related technologies, as well as tests on the far-field divergence angle, optical field distribution within the laser, and spectrum at different temperatures for AR-VCSEL arrays according to embodiments of this method. Each array consists of 37 lasers, with a distance of approximately 40 μm between adjacent lasers, and the optical aperture (aperture of the light-emitting hole) of each laser is 22 μm, forming a hexagonal light-emitting region with a size of approximately 250 μm (see Figure 31 for the array diagram).

[0025] Figure 2 is a schematic diagram of the structure of a vertical cavity surface-emitting laser with a cavity extension layer related to the related technology. Each VCSEL in the VCSEL array is a cavity extension type VCSEL as shown in Figure 2. Referring to Figure 2, the cavity extension type VCSEL has an upper Bragg reflective layer 2, an active region 3 including an active layer with 6 junctions, a cavity extension layer 4, and a lower Bragg reflective layer 1. Here, the active layer includes a quantum well 01, a tunnel junction 02 is provided between adjacent active layers, and a current constriction layer 03 is provided within each active layer. Figure 3 is a far-field view of the laser array with the structure shown in Figure 2 at a distance of 50 mm. Referring to Figure 3, the far-field divergence angle of the VCSEL array in the related technology is measured to be 18.5°. Figure 4 shows the optical field intensity distribution and refractive index distribution for the structure shown in Figure 2. Referring to Figure 4, we can see the refractive index distribution and electric field intensity distribution (epitaxial direction: from left to right) along the vertical axis after normalizing the output level. The electric field intensity distributed throughout the active region 3 and the electric field intensity of the resonator extension layer 4 are relatively uniform, and the difference between the peak electric field intensity value distributed throughout the active region 3 and the peak electric field intensity value of the resonator extension layer 4 is small. The laser wavelength is designed to be 905 mm. The resonator extension layer 4 functions as a higher-order mode filter by suppressing the generation of higher-order transverse modes, thereby reducing the divergence angle from the range of 20° to 30° to 18.5°. The reason for this is analyzed as follows.

[0026] In a VCSEL, a current-constricting layer 03 is provided within or near the outside of the active region 3. The current-constricting layer 03 comprises an oxide layer, which is epitaxially grown high-Al-component AlGaAs. An insulating aluminum oxide film layer is formed in the oxidized region outside of the oxide layer, and in the unoxidized region, an emission region where the active current is injected, i.e., a laser emission hole, is formed. The AlGaAs between the current-constricting layers 03 has a different refractive index than the outer aluminum oxide. This results in a difference in the effective refractive index inside and outside the VCSEL emission hole. The effective refractive index is given by the formula... Determined based on JPEG2026517353000018.jpg1167, Here, TIFF2026517353000019.tif610 is the effective refractive index. TIFF2026517353000020.tif610 is the refractive index in the z-axis direction. TIFF2026517353000021.tif69 represents the optical field intensity in the z-axis direction (i.e., the direction of light emission). The integration range is the range in which the optical field exists in the laser.

[0027] The difference in effective refractive index between the inside and outside of the VCSEL light-emitting hole is given by the formula Determined based on JPEG2026517353000022.jpg789, Here, TIFF2026517353000023.tif610 is the difference in effective refractive index between the inside and outside of the light-emitting hole. TIFF2026517353000024.tif613 is the effective refractive index of the region where the light-emitting holes are located. TIFF2026517353000025.tif613 is the effective refractive index outside the light-emitting hole. TIFF2026517353000026.tif67 is a material with a high aluminum content (e.g., Al 0.98 Ga 0.02 The refractive index of As) TIFF2026517353000027.tif67 is the refractive index of aluminum oxide. TIFF2026517353000028.tif67 is the optical confinement factor of the oxide layer and is determined based on the formula JPEG2026517353000029.jpg1149, and here, TIFF2026517353000030.tif64 is the thickness of the current confinement layer 320 in the z-axis direction, TIFF2026517353000031.tif64 is the thickness of the entire optical field in the z-axis direction.

[0028] According to the step-index waveguide theory, in the radial symmetric refractive index profile of a weak index guide, there exists a linearly polarized (LP) transverse mode, which is suitable for the case of oxide-confined VCSELs. The beam quality of each LP mode is determined by the mode order. The lowest-order mode, i.e., the fundamental mode, has the highest beam quality, or the lowest M 2 factor (M 2 = 1). Therefore, when the mode is coupled from the waveguide to free space, the divergence angle is the smallest. The higher the mode order, the higher the M 2 factor (M 2 > 1) and the larger the divergence angle. The number and order of the allowed LP modes are largely determined by the effective refractive index contrast between the core region and the cladding region of the refractive index profile, which corresponds to the inside and outside of the VCSEL emission aperture. By minimizing TIFF2026517353000032.tif67 and TIFF2026517353000033.tif610, the number of allowed LP modes is reduced, resulting in a smaller divergence angle being generated. Increasing the resonator length (providing the resonator extension layer 4), placing the oxide layer at the node of the standing-wave electron field, and reducing the number and thickness of the oxide layers all contribute to the minimization of TIFF2026517353000034.tif67 and TIFF2026517353000035.tif610.

[0029] However, long resonator lengths also lead to new risks. The main problem is that the spacing of longitudinal modes or the free spectral range (FSR) is affected by the effective resonator length L. eff The increasing frequency of the laser causes the frequency to decrease, hindering the operation of a single longitudinal mode. The emission spectrum of a VCSEL displays not only the desired laser mode but also multiple laser wavelengths appearing on one or both sides of the designed laser wavelength. Figure 5 is a comparison of the array laser spectrum and the reflection spectrum of the FP longitudinal mode at different temperatures for a laser array with the structure shown in Figure 2. The left panel of Figure 5 shows the reflection spectrum of the entire VCSEL structure in Figure 2 (solid black line) and the photoluminescence spectrum (dashed gray line) measured by moving from the active region to align with the central FP tilt angle for illustrative purposes. The FP longitudinal mode appears in the reflection spectrum. The FSR has narrowed to approximately 7.5 nm. The full width at half maximum (FWHM) of the photoluminescence (PL) spectrum measured from active region 3 is approximately 20 nm, which is larger than the mode spacing. When two longitudinal modes are covered by the emission spectrum of the active region 3 and are within the stopbands of the top DBR (upper Bragg reflector) and bottom DBR (lower Bragg reflector), these two longitudinal modes emit laser light simultaneously. Referring to the right-hand figure in Figure 5, array laser spectra were observed at different temperatures (from 25°C to 125°C), and in all cases, two longitudinal laser modes appeared.

[0030] As shown in Figure 3, Although TIFF2026517353000036.tif67 has a divergence angle of only 0.131%, such laser arrays achieve a divergence angle of 18.5° (D86 full angle). However, for many applications, multi-longitudinal-mode lasers (right diagram in Figure 5) are unacceptable due to potential problems such as temperature instability and efficiency losses of the photodetector filter. Such multi-wavelength lasers can be compensated to some extent by reducing the stopband bandwidth of the top DBR (upper Bragg reflector layer 2) and decreasing the refractive index contrast, but this is limited by stress due to epitaxial thickness, wafer warping, and subsequent manufacturing difficulties. Achieving a D86 full angle of less than 16° is difficult in single-longitudinal-mode oxide VCSELs with five or more active layers. Better low-divergence designs are needed to make more effective use of the resonator length.

[0031] Figure 6 is a schematic diagram of the structure of another anti-reflective vertical cavity surface-emitting laser according to an embodiment of the present invention. Referring to Figure 6, each AR-VCSEL in the AR-VCSEL array is an anti-reflective vertical cavity surface-emitting laser as shown in Figure 6. Referring to Figure 6, the anti-reflective vertical cavity surface-emitting laser has an upper Bragg reflective layer 20, an active region 30 including a 6-junction active layer 310, an anti-reflective storage cavity 40, and a lower Bragg reflective layer 10. Tunnel junctions 330 are provided between adjacent active layers, and current constriction layers 320 are provided within each active layer 310. The anti-reflective storage resonator 40 comprises an anti-reflective layer 41 and an optical storage layer 42. The anti-reflective layer 41 is located between the optical storage layer 42 and the active region 30. The anti-reflective layer 41 is configured to increase the optical field intensity peak value of the optical storage layer 42 until it is higher than the optical field intensity peak value of the active region 30. The optical storage layer 42 is configured to store optical field energy. Figure 7 is a far-field view of the laser array at 50 mm away, which has the structure shown in Figure 6. Referring to Figure 7, the measured far-field divergence angle of the AR-VCSEL array is 9.7°.

[0032] Along the direction from the active region 30 toward the anti-reflection storage resonator 40, the anti-reflection layer 41 includes a first anti-reflection interface located at the interface between the low refractive index and the high refractive index between the photo-storage layer 42 and the active region 30, and / or a second anti-reflection interface located at the interface between the high refractive index and the low refractive index between the photo-storage layer 42 and the active region 30. The optical path distance between the first anti-reflection interface and the nearest antinode of the standing wave optical field is less than 1 / 10 of the laser oscillation wavelength, and the optical path distance between the second anti-reflection interface and the nearest node of the standing wave optical field is less than 1 / 10 of the laser oscillation wavelength. Figure 8 shows the optical field intensity distribution and refractive index distribution of the structure shown in Figure 6. Referring to Figure 8, the anti-reflection layer 41 is formed by alternately providing multiple film layers (which may be called anti-reflection sublayers) with varying aluminum content, each having a thickness of 1 / 4 of the wavelength and being made of n-type doped AlGaAs. The photo-storage layer 42 may be a 2-micron thick film layer made of AlGaAs. The thickness of the photo-storage layer is an odd multiple of half the laser oscillation wavelength. Figure 8 illustrates that the anti-reflective layer 41 comprises a first anti-reflective interface and a second anti-reflective interface, and that the first and second anti-reflective interfaces are arranged sequentially and alternately. Between the active region 30 and the photo-storage layer 42, multiple anti-reflective interfaces are provided such that the electric field strength from the active region 30 to the photo-storage layer 42 gradually increases.

[0033] In the embodiment of the present invention, instead of simply extending the resonator on one side of the active region 30, an anti-reflective layer 41 is added, allowing light to be extracted from the active region 30 and stored in the photo-storage layer 42, thereby accommodating photons and improving the optical field intensity, much like an optical dam. As a result, the total electric field energy in the photo-storage layer 42 is several times that of a normal resonator extension layer with the same spatial volume. Preferably, the electric field intensity peak values ​​of the different active regions are the same or different, and the maximum electric field intensity peak value in the active region is less than the maximum electric field intensity peak value in the photo-storage storage resonator. As shown in Figure 8, when the two output levels are normalized to units, the electric field intensity peak value inside the photo-storage layer 42 is about three times the electric field intensity peak value of the active region 30 and about four to five times the electric field intensity peak value of the resonator extension layer 4 in Figure 4. Figure 9 is a comparison of the array laser spectrum and the FP longitudinal mode reflection spectrum of a laser array with the structure shown in Figure 6 at different temperatures. Referring to Figure 9, the strong electric field strength inside the photo-storage layer reduces the dependence of the divergence angle on the length of the resonator extension layer. Therefore, a smaller divergence angle can be achieved with only a photo-storage layer 42 of moderate length while maintaining a large FSR of approximately 16 nm (left panel in Figure 9). TIFF2026517353000037.tif67 is reduced by 0.027%, while single vertical mode (right image in Figure 9) is maintained.

[0034] Figure 10 is a comparison diagram of the optical intensity changes of a vertical-cavity surface-emitting laser in related technologies and an anti-reflective vertical-cavity surface-emitting laser in an embodiment of the present invention. Referring to Figure 10, a comparison is shown between the near-field electric field strength at the interface of the active region / lower Bragg reflective layer in a conventional VCSEL structure (left figure in Figure 10) and the near-field electric field strength at the interface of the active region / anti-reflective layer in an AR-VCSEL structure (right figure in Figure 10). The anti-reflective layer has a gap of 1 / 4 wavelength on the side of the active region 30, so that the position of the antinode of the electric field moves from the initial refractive index decreasing interface in the left figure of Figure 10 to the refractive index increasing interface in the right figure of Figure 10 along the direction from the active region 30 toward the lower Bragg reflective layer 10. In other words, the anti-reflective layer 41 consists of several pairs of film layers similar to the lower Bragg reflective layer 10, but a special π / 2 (1 / 4 wavelength) phase shift is designed. Photons generated from the active region 30 and propagated toward the lower Bragg reflective layer 10 undergo constructive interference in each anti-reflective sublayer, and their intensity gradually increases until they stabilize in the photostorage layer 42. In the AR-VCSEL structure shown in Figure 10, the anti-reflective layer 41 is located between the lower Bragg reflective layer 10 and the active region 30.

[0035] Figures 11 to 15 are diagrams illustrating the principle of constructing the electric field distribution in an anti-reflective vertical resonator surface-emitting laser according to an embodiment of the present invention. Referring to Figures 11 to 15, the electric field is established in the AR-VCSEL. Referring to Figure 11, a simple 0.5λ resonator type VCSEL with N-DBR and P-DBR is first shown using standing wave electric field strength and refractive index distribution diagrams. The N-DBR is equipped with multiple reflective mirrors whose optical thickness is 1 / 4 of the laser oscillation wavelength, and the multiple reflective mirrors are arranged alternately with high and low refractive indices. The P-DBR is equipped with multiple reflective mirrors whose optical thickness is 1 / 4 of the laser oscillation wavelength, and the multiple reflective mirrors are arranged alternately with high and low refractive indices. Compared with the electric field at both ends of the structure (the electric field strength at both ends of the structure is set to 1), the relative electric field strength inside the 0.5λ resonator (>50) is very high. Referring to Figure 12, the resonator length is then extended from 0.5λ to 10.5λ, and any resonator length of (1 / 2 + m / 2)λ (where m is a positive integer) does not affect the electric field distribution in the DBR. Referring to Figure 13, the thickness of one reflective mirror in the P-DBR is increased from 1 / 4λ to 3 / 4λ, and the thickness of the DBR can be (1 / 4 + m / 2)λ, where m is a positive integer, and increasing the additional spacing of one (m / 2)λ in the DBR does not create another resonator. Referring to Figure 14, the thickness of the 3 / 4λ layer in the P-DBR is increased to (11 + 3 / 4)λ, and the electric field strength distribution in all other locations remains unchanged. Referring to Figure 15, finally, the (11 + 3 / 4)λ layer is replaced with an active region having an optical thickness of (11 + 3 / 4)λ. By positioning multiple quantum wells as antinodes of the electric field standing wave, and simultaneously positioning tunnel junctions and oxide layers as nodes, the electric field distribution can be maintained to the maximum extent. No further resonators are added during this process. The first 10.5λ resonator becomes the photostorage layer.

[0036] In the unique design configuration of the embodiment of this application, a long resonator extension is converted to a shorter extension, but the electric field becomes stronger. Such an anti-reflection storage resonator 40 can store photons more effectively within a unit resonator length, TIFF2026517353000038.tif67 is more effectively reduced. Photons accumulated in the light storage layer are almost "free" in the lateral direction with little constraint from the sides, so the overall divergence angle is significantly reduced. In some embodiments of the present application, the light confinement factor of the oxide layer TIFF2026517353000039.tif67 has a gain of less than 0.16%.

[0037] Figure 16 shows the average M of a laser array having the structure shown in Figure 6 and a laser array having the structure shown in Figure 2 according to an embodiment of the present application. 2 This shows the relationship curve between factors and injection current, and a comparison diagram of array near-field and array far-field images. Referring to Figure 16, the average M of the lasers in the AR-VCSEL array... 2 The curve that changes with the factor injection current, and the average M of the laser in the resonator-extended VCSEL array. 2 The curves shown change with the injection current of the factor, and a comparison of near-field images (images e and b, and f and c in Figure 16, respectively) and far-field images (images g and d in Figure 16, respectively) of the AR-VCSEL array and the resonator-extended VCSEL array is shown. 2 The factor is directly proportional to the far-field divergence angle (FF). The file is JPEG2026517353000040.jpg629, and here, TIFF2026517353000041.tif65 is a full-size file in D86, TIFF2026517353000042.tif64 is a divergent half-width character ( (TIFF2026517353000043.tif614), average M of AR-VCSEL and resonator-extended VCSEL under different current injection levels. 2 All factors are stable. In the AR-VCSEL near-field image (e.g., image f in Figure 16), the sparse spots indicate a low number of lateral modes, which are reduced. This matches TIFF2026517353000044.tif67. Near-field and far-field images were measured with a current of 10A. It is assumed that the beam waist radius (r) is equal to the optical aperture radius, and the mean M of the array. 2 The factors were calculated.

[0038] Figure 17 is a comparison diagram of various photoelectric characteristics of a laser array with the structure shown in Figure 6 and various laser arrays in related technologies. Referring to Figure 17, the performance of luminance, spectral luminance, and optical output power within a 10° field of view was compared for AR-VCSEL, Extended Cavity VCSEL, state-of-the-art commercial multi-junction VCSEL, and state-of-the-art commercial multi-junction EEL laser radar. The comparison results show that the AR-VCSEL according to the embodiment of this application shows significantly improved performance in all three indicators. For the same array size and layout, the power within the 10° field of view (FOV) of the AR-VCSEL is more than twice that of the Extended Cavity VCSEL. The luminance is 12.5 kW*mm -2 sr ー1 From 38.5kW*mm -2 sr ー1 It has increased threefold, and the spectral brightness is 12.2kW*nm -1 mm -2 sr -1 From 75.6kW*nm -1 mm -2 sr -1This represents an increase of more than six times. Due to the increase in higher-order mode losses, the external quantum efficiency is slightly reduced (see Figure 35). However, compared to state-of-the-art commercial multi-junction EEL laser radars, the AR-VCSEL of this application has more than doubled the power within the 10° FOV range. Although the brightness of the AR-VCSEL in this application is still lower than that of state-of-the-art EELs, the spectral brightness has more than doubled, which can improve the performance of medium- and long-range laser radars with narrowband filters. EELs can achieve similar spectral brightness at higher currents, but their value is lower because they lack narrowband filters that can accommodate the large temperature coefficient of their wavelength shift. Note that the anti-reflective layer 41 and the photo-storage layer 42 are not necessarily separable.

[0039] In one embodiment of the present application, Figure 18 shows the optical field intensity distribution and refractive index distribution for another anti-reflective vertical-cavity surface-emitting laser according to an embodiment of the present application. Referring to Figure 18, the anti-reflective layer may be embedded in the optical storage layer, thereby integrating the anti-reflective layer and the optical storage layer. The anti-reflective storage resonator 40 comprises a plurality of first semiconductor material layers 401 and a plurality of second semiconductor material layers 402, the first semiconductor material layers 401 and the second semiconductor material layers 402 are arranged sequentially and alternately, the number and optical thickness of the first semiconductor material layers 401 and the second semiconductor material layers 402 are the same, the refractive indices of the first semiconductor material layers 401 and the second semiconductor material layers 402 are different, and the thickness of the anti-reflective storage resonator 40 is an integer multiple of half the laser oscillation wavelength. Compared to the active region 30, the structure and phase can be made flexible if the electric field intensity is strengthened. The key to such field cross-sectional engineering is ensuring that the cumulative phase shift of the entire optical reservoir, i.e., the optical distance between the active region 30 and the lower Bragg reflective layer 10, is an integer multiple of half a wavelength. The anti-reflective storage resonator 40 according to the embodiment of the present invention offers great potential for engineering and customizing the optical intensity distribution in AR-VCSELs.

[0040] Note that the AR-VCSEL design differs from the dual-resonator design (active-inert resonator), the latter being primarily used for narrowband applications. When used for low-divergence purposes, the significant decrease in the electric field between the inert and active resonators is a significant drawback. Not only is it inefficient in reducing TIFF2026517353000045.tif611, but it also leads to an increase in the total resonator length, which further reduces FSR. AR-VCSELs differ from passive resonator surface-emitting lasers, in which a thin active layer 310 is inserted into a high refractive index layer at 1 / 4 the wavelength of the top DBR (upper Bragg reflective layer 20), allowing the dielectric material to form a passive resonator, resulting in better temperature stability or mode control. The reflection-suppressed resonator in this paper is a single resonator body combining an active region 30 and an inactive region. The thickness of its multi-junction active region 30 is usually far greater than the total thickness of its top DBR. Furthermore, considering the loss mechanism of the reflection-suppressed resonator, the reflection-suppressing mirror or layer inside the photo-storage layer cannot be treated as part of the top DBR because it does not cause losses in the external mirror.

[0041] Based on the above multiple embodiments, both placing an oxide layer (current constriction layer 320) at the standing wave electron field node and / or reducing the thickness of the oxide layer are possible. TIFF2026517353000046.tif67 and To contribute to minimizing TIFF2026517353000047.tif612, in one embodiment of the present application, the optical path distance between the current-constricting layer 320 and the nearest zero-value position of the standing wave optical field is set to less than 1 / 10 of the laser oscillation wavelength. The current-constricting layer 320 is provided to be located at the zero-value position of the standing wave optical field. To ensure the current-constricting effect of the current-constricting layer 320, if the current-constricting layer 320 is outside the active region 30, the current-constricting layer 320 is provided to be located within two wavelength ranges along a direction perpendicular to one side of the active layer 310. The number of layers of the current-constricting layer 320 is less than or equal to the number of layers of the active layer 310 and less than or equal to the number of tunnel junctions 330 + 1.

[0042] and / or, the light-emitting pores of the AR-VCSEL are located in an unoxidized region of the oxide layer. TIFF2026517353000048.tif66 and To reduce the size of TIFF2026517353000049.tif610, the thickness of the oxidized portion of the oxide layer near the outer edge of the optical hole is set to less than 30 nm. The thickness of the oxidized portion of the oxide layer near the outer edge of the optical hole is less than 20 nm, and the thickness of the oxidized portion of the oxide layer near the outer edge of the optical hole is less than 15 nm.

[0043] Based on the above embodiments, along the direction opposite to the laser emission direction, the anti-reflective vertical-cavity surface-emitting laser sequentially comprises an active region having a dielectric layer, an electrical contact layer, a transverse current diffusion layer, a p-type upper Bragg reflective layer, an oxide layer, an anti-reflective storage resonator, an n-type lower Bragg reflective layer, and a substrate. Referring to Figure 1, the active layer 310 comprises a PIN structure including at least one quantum well 302, and the active layers 310 are connected in series via a tunnel junction 330. Each active layer 310 may be understood to include a quantum well 302 and an N-type semiconductor layer 303 and a P-type semiconductor layer 301 located on either side thereof. Each active layer 310 has at most one current-constricting layer 320, where the optical path distance between the tunnel junction 330 and the nearest standing wave optical field node is less than 1 / 10 of the laser oscillation wavelength. Preferably, the tunnel junction 330 is located at a standing wave optical field node. The tunnel junction 330 has very high doping, and this doping causes light absorption loss and reduces luminescence efficiency. Therefore, by placing the tunnel junction 330 in the location of the smallest light field, light loss can be minimized. In the structure of multiple active layers 310, only one current-constricting layer 320 may be provided, and this current-constricting layer 320 is located in the active layer 310 closest to the upper Bragg reflector layer 20.

[0044] When the active layer 310 contains one quantum well 302, the optical path distance between the quantum well 302 and the nearest standing wave light field peak is less than 1 / 5 of the laser oscillation wavelength. When the active layer 310 contains multiple quantum wells 302, the optical path distance between the overall center position of each of the multiple quantum wells 302 and the nearest standing wave light field peak is less than 1 / 10 of the laser oscillation wavelength. Preferably, the overall center position of each quantum well 302 is aligned with the electric field peak value. Since the quantum well is where laser gain amplification occurs, a greater amplification effect can be obtained by aligning the overall center position of each quantum well 302 with the position where the light field is strongest.

[0045] The anti-reflective vertical-cavity surface-emitting laser further comprises an ion-implanted layer, the ion-implanted layer located on the surface of the substrate near the n-type underbragg reflective layer and configured to enhance electrical insulation between the substrate and the n-type underbragg reflective layer, or the ion-implanted layer located at the bottom of an oxide trench and configured to enhance electrical insulation between the bottom of the oxide trench and the substrate, and the current-constricting layer is formed by oxidizing the sidewalls of the oxide trench. The implanted ions include at least one of H ions, He ions, B ions and O ions.

[0046] Based on the above-described embodiments, the AR-VCSEL can achieve a low divergence angle and improve the output optical power by increasing the number of junctions in the active layer 310. In order to expand the divergence angle range and satisfy different application purposes, the embodiments of the present invention use different We designed and experimented with over 50 AR-VCSEL and resonator-extended VCSEL structures with TIFF2026517353000050.tif67. These designs included 5, 6, 8, 10, and 14-junction AR-VCSELs, as well as a 6-junction resonator-extended VCSEL, each fabricated on the same 250 μm array pattern, tested at room temperature with a repetition frequency of 20 kHz, the same 3 ns pulse drive conditions, and an injection current of 10 A. The test results are shown in Figures 19 to 21 below.

[0047] Figure 19 is a diagram showing the relationship between the divergence angle and the light-trapping factor of the oxide layer in the embodiment of the present application, and as shown in Figure 19, the divergence angle and A clear correlation exists between TIFF2026517353000051.tif67 and the data. Almost all AR-VCSELs and resonator-extended VCSELs, regardless of the number of junctions, follow the same trend line. The dashed trend line reveals an approximate linear relationship between the divergence angle and the oxidation constraint factor, where the laser divergence angle is positively correlated with the photoconfinement factor of the oxide layer. Through careful design, the AR-VCSELs according to the embodiments of this application were able to precisely control the divergence angle (D86) from 8° to 25°. According to the inventors' research, this is the first time that an ultra-small divergence angle (D86) of less than 10° for a multi-junction VCSEL array has been achieved by optimizing the epitaxial structure alone, without using any type of lens, transverse grating, or two-dimensional photonic crystal structure, using only single longitudinal mode operation. The circular dots represent measurement data points for 46 AR-VCSEL epitaxial designs, where solid dots represent the AR-VCSELs in Figure 6. The triangular dots represent measurement data points for eight extended resonator VCSEL designs, where the entities represent the extended resonator VCSELs in Figure 2. The green, red, purple, brown, and blue circles represent AR-VCSEL arrays of 5J (7 designs), 6J (32 designs), 8J (3 designs), 10J (3 designs), and 14J (1 design), respectively.

[0048] Figure 20 shows the relationship between the divergence angle and the effective resonator length according to the embodiment of the present application. As shown in Figure 20, the AR-VCSEL array always exhibits a low divergence angle at the same resonator length. Even with the same effective resonator length, It should also be noted that the divergence angle does not form a single linear relationship with the effective resonator length, as TIFF2026517353000052.tif67 can change.

[0049] Figure 21 is a diagram showing the relationship between the laser array brightness, spectral width, and spectral brightness, respectively, and the photoconfinement factor of the oxide layer in an embodiment of the present application. The left diagram in Figure 21 shows the array brightness for 10A and 6 junctions of the AR-VCSEL array and the resonator-extended VCSEL array. Relationship curve and spectral width of TIFF2026517353000053.tif67 The relationship curve with TIFF2026517353000054.tif67 is shown, and the right figure in Figure 21 shows the array spectral brightness for AR-VCSEL arrays and resonator-extended VCSEL arrays with 10A and 6 junctions. The relationship curve with TIFF2026517353000055.tif67 is shown. For a fair comparison, the same number of junctions is used between the AR-VCSEL array and the resonator-extended VCSEL array. As can be seen from Figure 21, the laser brightness is negatively correlated with the photoconfinement factor of the oxide layer, and the laser spectral brightness is negatively correlated with the photoconfinement factor of the oxide layer. Because the light-emitting area is fully utilized, in the embodiments of this application, the maximum brightness achieved using six junctions in an AR-VCSEL array with a size of 250 microns is approximately 40 kW*mm -2 sr -1 The maximum brightness of a single laser is approximately 140 kW*mm². -2 sr -1 In the case of 10A, the spectral brightness achieved by the AR-VCSEL array is approximately 75.6 kW*nm. -1 mm -2 sr ー1 Therefore, with a single laser, approximately 260kW*nm -1 mm -2 sr ー1 It is similar to the state-of-the-art laser radar EEL level, and at high currents (EEL), it is typically 120kW*nm -1 mm -2 sr ー1 However, it cannot be used without a suitable filter wavelength shift. For reference, the most advanced VCSEL arrays used in laser radar in related technologies are approximately 12 kW*nm. -1 mm-2 sr ー1 The spectral brightness remains moderate. Because the number of junctions in the AR-VCSEL can be increased, the capacity of the light-emitting layer can be significantly expanded, reducing the emission size of the array. This allows the spectral brightness and power of the AR-VCSEL to be improved by several times, or even by an order of magnitude. Exemplarily, in one embodiment of the present invention, a 6-junction AR-VCSEL array with a diameter of 100 μm is given 100 kW.mm². -2 sr ー1 Brightness exceeding that of previous models has been achieved (see Figure 30). In short, the AR-VCSEL maintains the most cost-effective power per unit area while possessing the characteristics of high spectral brightness, high beam quality, and excellent temperature stability.

[0050] Number of active layer junctions and phototrapping factors of the oxide layer In addition to modifying TIFF2026517353000056.tif67, one embodiment of the present application also considers another key parameter, the aperture value of the optical aperture (OA), i.e., the aperture size of the light-emitting hole. Preferably, the range of the aperture value is 3 μm to 22 μm. Figure 22 shows the average M of AR-VCSEL arrays with different optical apertures according to an embodiment of the present application. 2 This is a relationship curve diagram between the factor and current density, referring to Figure 22. In the embodiment of the present application, a series of AR-VCSEL arrays with a size of 250 μm are provided, and each array is densely packed with the same AR-VCSELs. The aperture values ​​of the optical aperture OA include 7 μm, 9 μm, 11 μm, 13 μm, 15 μm, 17 μm, 19 μm and 21 μm, and all epitaxial structures, for example the epitaxial structures shown in Figure 6, are all identical. Subsequently, their divergence angles were measured, and the average M in these arrays was determined. 2 The value was calculated. According to the results of the study, the size of the aperture value of the optical aperture OA and M 2 A clear correlation exists between the values, and as shown in Figure 22, as the size of the optical aperture OA decreases, M 2 The value also becomes smaller. When the aperture size becomes as small as 7um, M 2It should be noted that since the value approaches 1, it was found that the emitter in the AR-VCSEL array can operate in a state of nearly a single transverse-mode laser.

[0051] To thoroughly examine a 7µm OA array sample and confirm the potential of a single-mode laser, the embodiments of this application were tested using a 100 ns pulse driver. This allows for better control of the AR-VCSEL array with lower currents and contributes to determining the conversion point between single-mode and multi-mode laser emission. Referring to Figure 36, light emitted from one specific emitter (AR-VCSEL) is coupled to an optical fiber (MM-Fibre) via a free-space lens numerical aperture (NA) (all other emitters in the laser array are completely optically blocked by silver paste). Figure 23 shows the laser spectra of the 7-micron optical aperture AR-VCSEL according to the embodiments of this application at different output powers, referring to Figure 23, where the optical output powers include 35.4 mW, 30.6 mW, 28.4 mW, 26.1 mW, 18.3 mW, and 9.4 mW. The optical power is 28.4mW, the current is approximately 7.8mA (calculated by dividing the total array current by the number of emitters), and the current density is approximately 200A / mm². 2 In this case, the spectrum showed that the side-mode suppression ratio (SMSR) of the single-mode laser reached nearly 40 dB. This demonstrated that a high-power single transverse-mode laser was realized in the AR-VCSEL array under 100 ns pulse conditions. The peak power of the emitter was 28.4 mW, exceeding the highest power of 14 mW reported in the literature for multi-junction VCSEL single-mode lasers. Note that the AR-VCSEL with a 7-micron optical aperture is much larger than conventional single-mode VCSELs, which typically have an aperture of 3-4 microns and lack extra surface roughness or complex structures.

[0052] Figure 24 is a comparison of measured near-field and far-field images at different output powers for an AR-VCSEL with a 7-micron optical aperture according to an embodiment of the present application. In this embodiment, near-field images (first row) and far-field images (second row) of light emitted from the light-emitting aperture were also observed. The light field is slightly elliptical, possibly because the circular shape of the light-emitting aperture is not perfect. Analysis of the side view of the far-field intensity reveals that its shape is very similar to a Gaussian curve. In the case of an AR-VCSEL with an optical aperture of 7 μm, its far-field divergence angle is 9.4°, which is close to the diffraction limit, and this is one of the important characteristics of single-mode operation.

[0053] At this stage, we must acknowledge that the present invention cannot definitively confirm the optical mode agreement between continuous waves (e.g., in many previous single-mode VCSEL operations) and pulsed conditions (e.g., in this operation). This point requires further investigation. Furthermore, it should be noted that in AR-VCSEL arrays and conventional VCSEL arrays, light emitted from a single emitter lacks coherence with one another. Therefore, even if each emitter operates in single mode, the optical field of the entire array cannot be considered single-mode. Instead, it represents a superposition of multiple single-mode optical fields.

[0054] In one embodiment of the present invention, the performance of the AR-VCSEL array was further compared with that of other semiconductor lasers in laser radar applications, such as photonic crystal surface-emitting laser (PCSEL) arrays. PCSEL arrays have recently been seen as a promising type of laser radar light source due to their extremely high brightness. However, their low power density may limit such applications. Figure 25 is a comparison chart of brightness and unit area power for the AR-VCSEL according to an embodiment of the present invention and other types of semiconductor lasers in laser radar applications, with the relationship between brightness and unit area power for various semiconductor lasers created in Figure 25. Figure 26 is a comparison chart of spectral brightness and unit area power for the AR-VCSEL according to an embodiment of the present invention and other types of semiconductor lasers in laser radar applications, with the relationship between spectral brightness and unit area power for various semiconductor lasers created in Figure 26. In the competition for long-range laser radar, the laser arrays shown in the lower right corner of Figures 25 and 26 (100 μm 18-junction AR-VCSEL array, 100 μm 6-junction AR-VCSEL array, 250 μm 14-junction AR-VCSEL array, and 250 μm 6-junction AR-VCSEL array) will become important. Figure 35 is a comparison of the photoelectric characteristics of various AR-VCSEL arrays according to embodiments of the present application and various high-power laser arrays according to related technologies. Referring to Figure 35, the various AR-VCSEL arrays include 250 μm 6-junction AR-VCSEL arrays, 100 μm 6-junction AR-VCSEL arrays, and 250 μm 14-junction AR-VCSEL arrays. Various high-power laser arrays according to related technologies include EEL arrays and PCSEL arrays. The relationship curves between optical power density and current density, the relationship curve between optical power and input electrical power within a 10° field of view, the relationship curve between total output power and current, and the relationship curve between external quantum efficiency and current were observed and compared for AR-VCSEL arrays and other types of laser radar semiconductor laser arrays. The power (current) density of the EEL was calculated by dividing the power (current) by the ridge area. The power density of all surface-emitting lasers was calculated by dividing the power by the total emission area.

[0055] Regarding divergence angle and brightness, for a 200m long-range scanning laser radar, a collimated beam with a divergence angle <0.03° is required to generate a 10cm spot size. PCSELs provide a divergence angle of approximately 0.1°, significantly reducing the size of the collimating lens, and even eliminating the need for a collimating lens altogether at shorter distances or lower resolutions. From this perspective, PCSELs have the advantage of low etendue and tolerate a small spot size after collimation. However, if the laser spot size is less than the spatial resolution of the sensor, there are no further advantages. Current scanning laser radars have a power output of 10-20kW*mm. -2 sr ー1 The brightness is sufficient to fit a sensor array with 10 μm spacing. The brightness range according to the embodiment of this application is 30~60 kW*mm -2 sr ー1 While AR-VCSEL light sources are sufficient to accommodate next-generation sensor arrays with spacing of approximately 6µm or three times the current pixel resolution, development may take several years.

[0056] Furthermore, Figure 27 is a schematic diagram of the structure of a rectangular laser array consisting of four rectangular AR-VCSELs according to an embodiment of the present application; Figure 28 is a schematic diagram of a far-field image measured with an injection current of 5.5A on the structure shown in Figure 27; Figure 29 is a laser spectral diagram measured by injecting an injection current of 5.5A into the structure shown in Figure 27 at different temperatures (25°C, 50°C, 75°C, 100°C, 125°C); and Figure 30 is a curve diagram of various photoelectric characteristics of the structure shown in Figure 27, each including the relationship curve between optical power and current within the total divergence angle, the relationship curve between optical power and current of light within a 10° divergence angle in the laser, the relationship curve between power conversion efficiency and current, the relationship curve between optical power density and current, the relationship curve between brightness and current, and the relationship curve between spectral brightness and current. Referring to Figures 27 to 30, the 100kW*mm of the 100μm size AR-VCSEL array according to an embodiment of the present application -2 sr ー1Brightness can meet the requirements of detector pixels with a brightness lower than 5 μm. With increasing the number of junctions, reducing the area, decreasing the oxide layer, and strengthening the light storage layer, brightness can be increased to 200-1000 kW*mm -2 sr ー1 This enables the realization of an AR-VCSEL array, which is compatible with higher resolution sensor arrays.

[0057] In terms of power density or kilowatts per chip area, the greatest advantage of AR-VCSELs over PCSELs is power density. Chip area determines the number of chips manufactured on a fixed-size semiconductor substrate, such as the 6-inch GaAs substrate widely used in VCSEL manufacturing. If the substrate type, epitaxial thickness and regrowth cycles, number of manufacturing layers and complexity, and test time on the wafer are all similar, the overall manufacturing cost of the wafer will be similar. Thus, the unit cost of the manufactured chips is directly proportional to the chip area. Therefore, to reduce costs, smaller chip sizes are most desirable for generating the same power. While PCSELs can improve power density at the expense of beam quality, experimental reports indicate that the peak power density of PCSELs is approximately 60 W / mm². 2 There is no other option. AR-VCSEL and VCSEL have a load capacity of 1000W / mm². 2 (Figure 25) can be easily exceeded. As shown in Figure 25, the optical power range that the 100um rectangular 6-junction AR-VCSEL array according to the embodiment of the present invention can provide is a peak power of approximately 45 W, and the optical power density range is approximately 4500 W / mm². 2 That is the case.

[0058] Furthermore, Figure 31 is a schematic diagram of the structure of a hexagonal laser array consisting of 37 hexagonal AR-VCSELs according to an embodiment of the present application; Figure 32 is a schematic diagram of a far-field image measured with an injection current of 10A on the structure shown in Figure 31; Figure 33 is a laser spectral diagram measured by injecting an injection current of 10A into the structure shown in Figure 31 at different temperatures (25°C, 65°C, 105°C, 125°C); and Figure 34 is a curve diagram of various photocurrent characteristics of the structure shown in Figure 31, each including a curve relating optical power and current within the total divergence angle, a curve relating optical power and current within a 10° divergence angle in the laser, a curve relating power conversion efficiency and current, a curve relating optical power density and current, a curve relating brightness and current, and a curve relating spectral brightness and current. Referring to Figures 31 to 33, a 14-junction AR-VCSEL array with a size of 250um has a peak power of approximately 240W and approximately 5000W / mm². 2 It is possible to generate a light power density of [value missing].

[0059] Based on these figures, a 100 μm square 18-junction AR-VCSEL array would generate 15,000 W / mm². 2It can be predicted that this is achievable. Ignoring the expensive photolithography and regrowth processes of PCSELs, and considering only semiconductor area usage, AR-VCSELs can generate the same optical power at 10 to 100 times lower cost than PCSELs. Lasers and sensor chips each account for 20-40% of the total laser radar cost. Under PCSEL technology, even if the cost of the light-emitting lens (20% of the total laser radar cost) is completely eliminated, the cost savings are still far lower than the 10-fold (conservative estimate) increase in total cost due to the larger chip area (2-4 times the total laser radar cost). The market needs to halve the cost of light sources to achieve the goal of keeping the material cost of long-range main laser radars under $100. In such laser radars, the total power of all light source chips is typically around 5 kilowatts. Therefore, $10 per kilowatt is a rough cost requirement for the laser chip. While AR-VCSELs, VCSELs, and even EELs can all more or less meet this cost requirement, PCSELs need to improve their power density by 10 to 100 times through several innovative technologies to be competitive. Similar to PCSELs, DBR lasers with stable wavelength temperature can also achieve good brightness and spectral brightness, but their power per chip area is located on the far left of Figure 25, making them more expensive and less competitive as laser radars. Both PCSELs and DBR lasers require complex manufacturing processes, such as electron beam lithography, nanoimprint lithography, and epitaxial regrowth.

[0060] In addition to laser radar, AR-VCSELs can also be used for structural optical 3D sensing due to their characteristics of a small divergence angle, high beam quality, and minimized crosstalk between emitters. For data communication applications, AR-VCSELs can potentially achieve single transverse mode, which reduces chromaticity and modal dispersion and has a larger oxidation aperture than conventional single-mode VCSELs.

[0061] Furthermore, the anti-reflective storage resonator 40 technology can facilitate other advanced surface-emitting laser technologies. For example, the z-direction optical reservoir in AR-VCSELs can be combined with xy-plane photonic crystals, topological resonators, or metasurface structures, potentially enabling higher output power and efficiency in these surface-emitting lasers.

[0062] Based on the above, the AR-VCSEL, which combines an anti-reflective storage resonator 40 with a multi-junction active region, maintains a single longitudinal mode laser while offering the advantages of a significantly smaller divergence angle, high brightness, and high spectral brightness. By individually reconfiguring the epitaxial layers, such a unique design does not require a complex device structure or further manufacturing steps. By employing a standard low-cost VCSEL process, an ultra-compact, perfect divergence angle of 8.0° (D86) or 4.1° (FWHM) is achieved in a 250 μm size 6-junction AR-VCSEL array, with a brightness of 40 kW* mm². -2 sr ー1 It exceeds that, with a spectral brightness of 75.6kW*nm -1 mm -2 sr ー1 This means that by adopting a more compact 100μm-sized array, the AR-VCSEL array brightness will be 100kW*mm -2 sr ー1 The performance has improved to the above, with spectral brightness reaching 180kW*nm -1 mm -2 sr ー1 This improves performance even further. By increasing the number of junctions and using a 14-junction AR-VCSEL array with a size of 250um, the performance can reach 5000 W / mm². 2This power density is achieved. By changing the oxidation aperture size, a 28.4 mW high-power single transverse-mode laser is realized in a 6-junction AR-VCSEL single emitter with an optical aperture of 7 μm. To the best of the applicant's knowledge, these are the best-performing multi-junction VCSELs published to date. AR-VCSELs offer more advantages over competing EELs, complementing scalable high power output, a nearly circularly symmetric beam, and temperature-dependent wavelength drift suitable for filtering. This application further compares AR-VCSELs and PCSELs from multiple perspectives, revealing that power density is the most difficult challenge for PCSELs, while power density is key to low-cost laser radars. Overall, AR-VCSELs demonstrate a well-balanced performance across various laser radar requirements. In particular, for high-power, low-cost scanning laser radars requiring 16° (D86) or lower divergence, employing an AR-VCSEL is the optimal solution.

[0063] The photoelectric characteristics of all VCSEL / ARVCSEL arrays were tested under short-pulse conditions, with a pulse width of 3 ns, a frequency of 20 kHz, and a test environment temperature of room temperature. As shown in Figure 37, the drive circuit comprises a capacitor charge / discharge circuit 1011 and a capacitor charge / discharge drive circuit 1013. The capacitor charge / discharge circuit 1011 comprises a charging resistor R1, a charge / discharge capacitor C1, and a power supply 1012. The negative terminal of the power supply 1012 is grounded, the positive terminal of the power supply 1012 is electrically connected to one end of the charging resistor R1, the other end of the charging resistor R1 is electrically connected to one end of the charge / discharge capacitor C1, the other end of the charge / discharge capacitor C1 is grounded, and the connection terminal between the other end of the charging resistor R1 and the charge / discharge capacitor C1 is further electrically connected to one end of the light source 102. The capacitor charge / discharge drive circuit 1013 comprises a switching transistor Q1 and a switching transistor drive circuit 1014. One end of the switching transistor drive circuit 1014 is grounded, the other end is electrically connected to the first end of the switching transistor Q1, the second end of the switching transistor Q1 is grounded, and the third end of the switching transistor Q1 is electrically connected to the other end of the light source 102.

[0064] Photoluminescence spectra were measured using an OBIS LS 532nm continuous laser with an optical power of 20mW and a spot size of 20um at room temperature, employing the Nanometrics RPMBlue system. Far-field patterns were acquired using an Ophir L11059 beam profiler camera with an operating current of 10A. Optical output power was measured using a Newport 819D-SL-3.3 integrating sphere. Laser spectra were acquired using an Ocean Insight HR4Pro spectrometer with an operating current of 10A and a resolution of 0.2nm. Single-mode laser spectra were acquired using an MS9740A spectrometer with a resolution of 0.07nm. Two-dimensional electric field strength simulations were performed using the Ansys Lumerical FDTD solution. Full vector simulations were performed using the Perfectly Matched Layer (PML) boundary condition, yielding final simulation results with an auto-off minimum of 1E-5 and an auto-off maximum of 1E5. Simulations were performed with and without gain in the active layer. By comparing the normalized E(z) field strength distribution maps with and without gain, the difference was less than 0.1%, demonstrating a stable static distribution.

[0065] Embodiments of the present invention further provide an anti-reflective vertical cavity surface-emitting laser chip comprising at least one laser array, wherein the laser array comprises a plurality of anti-reflective vertical cavity surface-emitting lasers of any embodiment of the present invention, and the laser array is a regularly arranged array, or a randomly arranged array, or an array having a plurality of addressable sub-arrays.

[0066] Preferably, the size of the laser array is 250 μm or less, and the brightness of the laser array is 40 kW* mm -2 sr ー1 The above is the result, and the spectral brightness is 75.6 kW * nm -1 mm -2 sr ー1 That's all.

[0067] Preferably, when the number of junctions in the active layer of the anti-reflective vertical-cavity surface-emitting laser is 14 or more, the optical power density of the anti-reflective vertical-cavity surface-emitting laser chip is 5000 W / mm². 2 That's all.

[0068] In the embodiments of this application, the shape of the laser array can be a rectangle, a circle, a regular hexagon, or any other shape. In the case of a rectangular laser array, its size is its length or width. In the case of a circular laser array, its size is its diameter. In the case of a regular hexagonal laser array, its size is the diameter of its inscribed circle.

[0069] It should be understood that the steps can be rearranged, added, or deleted using the various forms of flows described above. For example, the steps described in this application may be executed in parallel, sequentially, or in different orders, as long as the desired results of the proposed technology are achieved, and this paper is not limited thereto.

Claims

1. The lower Bragg reflective layer, An active region located on one side of the lower Bragg reflective layer, which includes at least five active layers and tunnel junctions located between the active layers, An upper Bragg reflective layer located on the side of the active region away from the lower Bragg reflective layer, An anti-reflective storage resonator located at least one location between the lower Bragg reflective layer and the active region, and between the upper Bragg reflective layer and the active region, An anti-reflective vertical cavity surface-emitting laser comprising: The aforementioned anti-reflective storage resonator is configured to increase the optical field intensity peak value until it is higher than the optical field intensity peak value of the active region, and to store optical field energy. Here, a current-constricting layer is provided within or near the outside of the active region, the current-constricting layer comprises an oxide layer, the oxide layer is an epitaxial film layer in which the epitaxially grown Al component is higher than a preset value, an insulating aluminum oxide film layer is formed in the oxidized region outside thereof, a light-emitting region into which an active current is injected is formed in the unoxidized region, the optical aperture of the anti-reflective vertical-cavity surface-emitting laser is located in the current injection region, and the laser output from the anti-reflective vertical-cavity surface-emitting laser is a single transverse-mode laser. Anti-reflective vertical cavity surface-emitting laser.

2. The optical path distance between the current-constricting layer and the nearest zero-value position of the standing wave optical field is less than 1 / 10 of the laser oscillation wavelength, and when the current-constricting layer is outside the active region, it is located within two wavelength ranges along a direction perpendicular to one side of the active layer, and the number of layers in the current-constricting layer is less than or equal to the number of layers in the active layer and less than or equal to the number of tunnel junctions + 1. The anti-reflective vertical cavity surface-emitting laser according to claim 1.

3. The oxide layer further comprises a light-emitting hole located in an unoxidized region, the optical aperture being the opening of the light-emitting hole, and the thickness of the oxide layer near the outer edge of the light-emitting hole being less than 30 nm. The anti-reflective vertical cavity surface-emitting laser according to claim 2.

4. The divergence angle of the laser is positively correlated with the photoconfinement factor of the oxide layer. The brightness of the laser is negatively correlated with the phototrapping factor of the oxide layer. The spectral brightness of the laser is negatively correlated with the phototrapping factor of the oxide layer. The anti-reflective vertical cavity surface-emitting laser according to claim 2.

5. The light-trapping factor of the oxide layer is less than 0.16%. The anti-reflective vertical cavity surface-emitting laser according to claim 4.

6. The diameter range of the optical aperture is 3 μm to 22 μm. The anti-reflective vertical cavity surface-emitting laser according to claim 1.

7. The active layer comprises a PIN structure including at least one quantum well, and the active layer is connected in series via the tunnel junction. When the active layer contains one quantum well, the optical path distance between the quantum well and the nearest standing wave light field peak is less than 1 / 5 of the laser oscillation wavelength. When the active layer contains multiple quantum wells, the optical path distance between the overall center position of each of the multiple quantum wells and the nearest standing wave light field peak is less than 1 / 10 of the laser oscillation wavelength. The anti-reflective vertical cavity surface-emitting laser according to claim 1.

8. Along the direction opposite to the laser emission direction, the anti-reflective vertical resonator surface-emitting laser sequentially comprises a dielectric layer, an electrical contact layer, a transverse current diffusion layer, a p-type upper Bragg reflective layer, an active region having an oxide layer, the anti-reflective storage resonator, an n-type lower Bragg reflective layer, and a substrate. The anti-reflective vertical cavity surface-emitting laser according to claim 1.

9. The electric field intensity peak values ​​of the different active layers are either the same or different, and the maximum electric field intensity peak value in the active region is less than the maximum electric field intensity peak value in the anti-reflective storage resonator. The anti-reflective vertical cavity surface-emitting laser according to claim 1.

10. The anti-reflective storage resonator comprises an anti-reflective layer and a light storage layer, the anti-reflective layer being located between the light storage layer and the active region, the anti-reflective layer being configured to increase the peak light field intensity value of the light storage layer until it is higher than the peak light field intensity value of the active region, and the light storage layer being configured to store light field energy. Here, the thickness of the light storage layer is an odd multiple of half the laser oscillation wavelength, and along the direction from the active region toward the anti-reflection storage resonator, the anti-reflection layer comprises at least one of: a first anti-reflection interface located at the interface between the light storage layer and the active region from a low refractive index to a high refractive index; and a second anti-reflection interface located at the interface between the light storage layer and the active region from a high refractive index to a low refractive index; the optical path distance between the first anti-reflection interface and the nearest antinode of the standing wave optical field is less than 1 / 10 of the laser oscillation wavelength; and the optical path distance between the second anti-reflection interface and the nearest node of the standing wave optical field is less than 1 / 10 of the laser oscillation wavelength. The anti-reflective vertical cavity surface-emitting laser according to any one of claims 1 to 9.

11. The aforementioned light-reflection-preventing storage resonator is The device comprises a plurality of first semiconductor material layers and a plurality of second semiconductor material layers, wherein the first semiconductor material layers and the second semiconductor material layers are arranged sequentially and alternately. The number and optical thickness of the first semiconductor material layer and the second semiconductor material layer are the same, the refractive indices of the first semiconductor material layer and the second semiconductor material layer are different, and the distance between the active region and the Bragg reflective layer adjacent to the anti-reflective storage resonator is an integer multiple of half the laser oscillation wavelength. The anti-reflective vertical cavity surface-emitting laser according to any one of claims 1 to 9.

12. Multiple anti-reflective interfaces are provided between the active region and the photo-storage layer such that the electric field strength from the active region to the photo-storage layer gradually increases. The anti-reflective vertical cavity surface-emitting laser according to claim 10.

13. The present invention comprises at least one laser array, wherein the laser array comprises a plurality of anti-reflective vertical-cavity surface-emitting lasers as described in any one of claims 1 to 12, and the laser array is a regularly arranged array, or a randomly arranged array, or an array having a plurality of addressable sub-arrays. Anti-reflective vertical cavity surface-emitting laser chip.

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