A multi-line lidar transceiver based on a TCSEL array

Abstract

This invention proposes a multi-line lidar transceiver based on a TCSEL array, comprising a TCSEL light source array, a filter, a first optical lens, a scanning system, a second optical lens, a detector array, and a substrate. The TCSEL light source array, filter, first optical lens, second optical lens, and detector array are all mounted on the substrate. The centers of the TCSEL light source array, filter, and first optical lens are aligned on the same horizontal line, as are the centers of the second optical lens and detector array. The filter and detector array transmission optical paths are matched. Light emitted from the TCSEL light source array enters the filter and is split into two beams. Beam I passes sequentially through the first optical lens, scanning system, and second optical lens before entering the detector array. Beam II is directly emitted into the detector array from the filter. This application integrates the device, reducing its size, and the array light source outputs multi-beam lasers, simplifying lidar design.

Description

Technical Field

[0001] This invention relates to the technical field of lidar transceivers, and more particularly to a multi-line lidar transceiver based on a TCSEL array. Background Technology

[0002] With the development of science and technology, lidar is widely used in fields such as autonomous driving, intelligent robot navigation, and smart cities. Currently, lidar based on the time-of-flight principle mainly includes mechanical lidar and hybrid solid-state lidar. The spectral width, multi-line operation capability, beam scanning range, size, and weight of lidar have a significant impact on its performance and mass application.

[0003] Currently, most lidar systems use 905nm wavelength semiconductor lasers (LDs) as their light source. However, the 905nm wavelength has low power, which is harmful to the human eye, limiting its maximum detection distance. Furthermore, the 905nm edge-emitting semiconductor laser has a wide spectral width, typically around 5nm, making it susceptible to noise. Current methods for achieving multi-line lidar operation mainly involve using multiple lasers operating simultaneously. Each laser at the emitting end requires different mounting angles to match the lens. This approach results in low system integration and poor matching accuracy between the detector (PD) and laser, making it unsuitable for mass production. Therefore, the use of vertical-cavity surface-emitting laser (VCSEL) arrays as the optical emission system has been proposed. While VCSELs are easy to fabricate into arrays, they still have a certain divergence angle, generally above 10°, posing challenges for beam control. Additionally, 1550nm VCSELs are difficult to fabricate. 1550nm lidar sources often use fiber lasers, but fiber lasers are large and expensive, hindering miniaturization and low-cost production of lidar. Their high cost also makes multi-line lidar fabrication difficult. Summary of the Invention

[0004] To address the technical problems of 1550nm lidar being difficult to operate in multiple lines, having a large size, and being expensive, this invention proposes a multi-line lidar transceiver device based on a TCSEL array, realizing a compact 1550nm lidar capable of multi-line operation.

[0005] To achieve the above objectives, the technical solution of the present invention is implemented as follows: A multi-line lidar transceiver based on a TCSEL array, characterized in that it includes a TCSEL light source array, a filter, a first optical lens, a second optical lens, a detector array, and a substrate. The TCSEL light source array, the filter, the first optical lens, the second optical lens, and the detector array are all disposed on the substrate. The optical paths of the TCSEL light source array, the filter, and the first optical lens are on the same straight line, and the optical paths of the second optical lens and the detector array are on the same straight line. The transmission optical paths of the filter and the detector array are matched. Both the first optical lens and the second optical lens are convex lenses. The light emitted from the TCSEL light source array enters the filter and is split into two beams. Beam I is reflected by the first optical lens and enters the second optical lens before entering the detector array. Beam II is directly emitted into the detector array by the filter.

[0006] The TCSEL light source array includes a semiconductor substrate, a quantum well, amorphous silicon, and an array light-emitting region. The semiconductor substrate, quantum well, and amorphous silicon are arranged sequentially from bottom to top, and the array light-emitting region is located within the amorphous silicon.

[0007] The amorphous silicon substrate has irregularly distributed rectangular grooves etched on its underside.

[0008] The array light-emitting region includes at least two optical cavities, which are linearly arranged at equal intervals within the amorphous silicon. The bottom of each optical cavity is connected to a quantum well. The number of optical cavities is a multiple of 2, and the centers of the optical cavities are aligned in the vertical direction.

[0009] The array light-emitting area includes at least two optical cavities, which are arranged at unequal intervals within the amorphous silicon. The number of light-emitting areas is a multiple of 2, and the centers of the optical cavities are aligned in the vertical direction.

[0010] Both the first optical lens and the second optical lens are microlens arrays. Each microlens array contains at least two microlenses with their centers vertically aligned. The number of microlenses is the same as the number of optical cavities, and the microlenses and optical cavities are arranged on the same horizontal line.

[0011] The substrate is a PCB printed circuit board.

[0012] The TCSEL light source array, filter, first optical lens, second optical lens, and detector array are all integrated on the substrate.

[0013] The semiconductor substrate is made of one of InP, GaAs, or GaSb.

[0014] The quantum well is made of one of InGaAsP, AlGaInAs, InGaAs, or GaAs.

[0015] The beneficial effects of the present invention are as follows: (1) The multi-line laser radar transceiver device based on TCSEL array described in the present invention realizes the core functions of laser radar beam transceiver, such as transmission and shaping of multiple output laser radar beams through TCSEL light source array, filter and first optical lens, and collection, shaping and transmission of laser radar beams through second optical lens and detector array.

[0016] (2) The multi-line lidar transceiver device based on TCSEL array described in this invention integrates the TCSEL light source array, filter, first optical lens, second optical lens and detector array on the substrate. This application effectively increases the compactness of the lidar transceiver device through integration and greatly reduces the size of the lidar transceiver device.

[0017] (3) The TCSEL laser array described in this invention serves as the emission light source, and the working wavelength of 1550nm increases the maximum detection range of the lidar.

[0018] (4) The TCSEL laser array described in this invention serves as the emission light source. The array light source enables the lidar to operate in multiple lines, which greatly facilitates the design and layout of the lidar.

[0019] (5) The TCSEL laser array described in this invention has a divergence angle of less than 1° as a light source, which solves the problems of light scattering and stray light interference inside the lidar. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the structure of the present invention.

[0022] Figure 2 This is a schematic diagram of the TCSEL array structure of the present invention.

[0023] Figure 3 This is a schematic diagram of the light emission part of the TCSEL light source array when the light emission area is linearly distributed.

[0024] Figure 4 This is a schematic diagram of the light emission part of the TCSEL light source array when the light emission region is nonlinearly distributed.

[0025] In the figure, 1 is the TCSEL light source array, 2 is the filter, 3 is the first optical lens, 4 is the lidar scanning system, 5 is the second optical lens, 6 is the detector array, 7 is the substrate, 8 is the semiconductor substrate, 9 is the quantum well, 10 is the amorphous silicon, 11 is the array light-emitting area, 12 is the first emitted beam, and 13 is the second emitted beam. Detailed Implementation

[0026] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] like Figure 1 As shown, a multi-line lidar transceiver based on a TCSEL array includes a TCSEL light source array 1, a filter 2, a first optical lens 3, a scanning system 4, a second optical lens 5, a detector array 6, and a substrate 7. The TCSEL light source array 1, filter 2, first optical lens 3, second optical lens 5, and detector array 6 are all mounted on the substrate 7. The centers of the TCSEL light source array 1, filter 2, and first optical lens 3 are aligned on the same horizontal line, as are the centers of the second optical lens 5 and detector array 6. The transmission optical paths of the filter 2 and detector array 6 are matched. This invention integrates the light source array 1, filter 2, first optical lens 3, second optical lens 5, and detector array 6 onto the substrate 7, achieving single-chip integration of lidar output light transmission and shaping functions with received light transmission and shaping functions. Compared to current mechanical lidar systems that use multiple light sources and lenses, this invention significantly reduces the size of the device. This invention achieves the transmission and shaping of multiple output light rays of the lidar through a TCSEL light source array 1, a filter 2, and a first optical lens 3, and achieves the collection, shaping, and transmission of the received light rays of the lidar through a second optical lens 5 and a detector array 6.

[0028] Among them, such as Figure 2As shown, the TCSEL light source array 1 includes a semiconductor substrate 8, a quantum well 9, an amorphous silicon 10, and an array light-emitting region 11. The semiconductor substrate 8, quantum well 9, and amorphous silicon 10 are arranged sequentially from bottom to top, and the array light-emitting region 11 is disposed within the amorphous silicon 10. The semiconductor substrate 8 is made of one of InP, GaAs, or GaSb, and its main function is to provide a substrate for growing laser epitaxial materials. The quantum well 9 is mainly used to achieve carrier recombination and emit laser light, and its material is one of InGaAsP, AlGaInAs, InGaAs, or GaAs. The amorphous silicon 10 has non-uniformly distributed rectangular grooves etched on its lower side. Figure 2 The white area represents the etched portion, and the shaded area represents the unetched portion. The primary function of etching the unevenly distributed rectangular grooves on the amorphous silicon 10 is to form Dirac vortex cavities. Multiple circular holes are etched on the amorphous silicon 10, each containing a light-emitting region composed of multiple small circles. The diameter of these circular holes can range from tens to hundreds of micrometers depending on the required output power of the TCSEL light source array 1. Since the divergence angle of the light generated by the TCSEL light source array 1 is less than 1°, no additional lens is needed between the filter 2 and the TCSEL light source array 1 for optical shaping, simplifying the system configuration. Furthermore, the TCSEL light source array 1 allows for multi-line operation of the lidar, greatly facilitating its design and layout. The light emitted from the TCSEL light source array 1 enters the filter 2, which is a 45° filter. The main function of the filter 2 is to separate the incident light from the TCSEL light source array 1 into light beam I and light beam II. Both the first optical lens 3 and the second optical lens 5 are microlens arrays. Each microlens array contains at least two vertically aligned microlenses, with the number of microlenses matching the number of light-emitting areas. The microlenses within the microlens array of the first optical lens 3 are positioned on the same horizontal line as the centers of the light-emitting areas. Light ray I enters the first optical lens 3 after passing through the filter 2. The main function of the first optical lens 3 is to shape light ray I to form collimated output light. For example... Figure 3As shown, the array emitting region 11 includes at least two emitting regions. When the emitting regions are linearly arranged, they are equally spaced within the amorphous silicon 10, and the number of emitting regions is a multiple of 2. The centers of each emitting region are vertically aligned. The main function of the scanning system 4 is to perform horizontal scanning of the collimated output light. The collimated output light is incident on the target object after entering through the first optical lens 3. After being reflected by the target object, the collimated output light enters the scanning system 4, and then is output from the scanning system 4 to the second optical lens 5. The main function of the second optical lens 5 is to shape the collimated output light received by the scanning receiving system 4 to form the target reflected light. The target reflected light output by the second optical lens 5 enters the detection scanning array 6 for scanning and analysis. The light beam II emitted by the filter 2 directly enters the detection scanning array 6 as a reference light for comparison with the target reflected light. This invention achieves the integration of laser radar beam transceiver, greatly reducing the size of the laser radar transceiver device.

[0029] like Figure 4 As shown, the array light-emitting area 11 includes at least two light-emitting areas. When the light-emitting areas are nonlinearly distributed, the light-emitting areas are nonlinearly arranged at unequal intervals on the upper side of the amorphous silicon 10. The number of light-emitting areas is a multiple of 2. By changing the spacing between the light-emitting areas, the middle position of the TCSEL light source array 1 can have a more compact light-emitting area, thereby increasing the scanning accuracy of the lidar in the middle part and outputting focused light such as the second emitted beam 13.

[0030] This patent describes a multi-line lidar transceiver based on a TCSEL array. It realizes the core functions of lidar beam transceiver, such as the transmission and shaping of multiple output beams, as well as the collection, shaping, and transmission of received beams. The integrated lidar transceiver greatly reduces its size. The array light source outputs multiple laser beams, which facilitates the design and layout of the lidar.

[0031] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A multi-line laser radar transceiver based on a TCSEL array, characterized in that, The application relates to a TCSEL light source array (1), a filter (2), a first optical lens (3), a second optical lens (5), a detector array (6) and a substrate (7), wherein the TCSEL light source array (1), the filter (2), the first optical lens (3), the second optical lens (5) and the detector array (6) are arranged on the substrate (7); the light paths of the TCSEL light source array (1), the filter (2) and the first optical lens (3) are on the same straight line, the light paths of the second optical lens (5) and the detector array (6) are on the same straight line, the filter (2) is matched with the transmission light path of the detector array (6), and the first optical lens (3) and the second optical lens (5) are both convex lenses. After the light emitted by the TCSEL light source array (1) enters the filter (2), the light is divided into two light rays, light ray I is reflected into the second optical lens (5) through the first optical lens (3) and then enters the detector array (6), and light ray II is directly injected into the detector array (6) from the filter (2); The TCSEL light source array (1) comprises a semiconductor substrate (8), a quantum well (9), amorphous silicon (10) and an array light emitting area (11), wherein the semiconductor substrate (8), the quantum well (9) and the amorphous silicon (10) are sequentially arranged from bottom to top, and the array light emitting area (11) is arranged in the amorphous silicon (10); and a plurality of rectangular grooves are unevenly distributed on the lower side of the amorphous silicon (10). The array light emitting area (11) comprises at least two light cavities, the light cavities are unevenly spaced in the amorphous silicon (10), the number of the light emitting areas is a multiple of 2, and the centers of the light cavities are aligned in the vertical direction. The first optical lens (3) and the second optical lens (5) are both microlens arrays, the microlens array comprises at least two vertically aligned microlenses, the number of the microlenses is consistent with the number of the light cavities, and the microlenses and the light cavities are correspondingly arranged on the same horizontal line.

2. The TCSEL array based multi-line lidar transceiver apparatus according to claim 1, wherein, The substrate (7) is a PCB (printed circuit board).

3. The multi-line laser radar transceiver based on a TCSEL array according to claim 2, characterized in that, The TCSEL light source array (1), the filter (2), the first optical lens (3), the second optical lens (5) and the detector array (6) are integrated on the substrate (7).

4. The TCSEL array based multi-line lidar transceiver apparatus according to claim 1, wherein, The material of the semiconductor substrate (8) is one of InP, GaAs and GaSb.

5. The multi-line laser radar transceiver based on a TCSEL array according to any of claims 1-4, characterized in that, The material of the quantum well (9) is one of InGaAsP, AlGaInAs, InGaAs and GaAs.

Images