WO2023174446A1 - Optical antenna and optical chip of phased array lidar - Google Patents

Abstract

The present application provides an optical antenna and an optical chip of a phased array lidar. The optical antenna comprises a transmission antenna array and a reception antenna array; the transmission antenna array comprises a plurality of transmission antenna units, and each transmission antenna unit has a length; the reception antenna array comprises a plurality of reception antenna units, and each reception antenna unit has a length; and the lengths of the transmission antenna units are greater than the lengths of the reception antenna units. In the optical antenna provided by the present application, the lengths of the transmission antenna units are greater than the lengths of the reception antenna units, the reception antenna units can maximally reduce the reflection of a laser echo, the laser echo can be received in a maximally large area, and the reception efficiency of the laser echo is also improved.

Description

An optical antenna and optical chip for phased array lidar

This application requests the priority of the invention patent application filed with the Patent Office of the State Intellectual Property Office on March 15, 2022, with the application number 202210251347.8 and the invention title "An optical antenna and an optical chip for phased array lidar" , the entire contents of which are incorporated herein by reference.

Technical field

The present application belongs to the field of radar technology, and more specifically, relates to an optical antenna and an optical chip of a phased array laser radar.

Background technique

Lidar, as a relatively advanced sensor at present, has been widely used in many fields, such as free space optical communications, unmanned driving and other fields. Among them, optical phased array lidar is a type of lidar. Silicon-based optical phased array uses silicon-based optoelectronic technology. Silicon-based optoelectronic technology can realize complex optoelectronic integrated systems on one chip. The integrated system is not only compact, but also The cost is low, so silicon-based optical phased array laser radar is used, which has the characteristics of small size and high integration.

The silicon-based optical phased array lidar system optical chip includes a transmitting optical phased array and a receiving optical phased array. The transmitting optical phased array can emit light into space; the receiving optical phased array receives the emitted light and detects it. The echo beam reflected by the object. For optical phased arrays, the structural parameters of the optical antenna are the decisive factors for the transmission and reception of the optical phased array, and the design of the transmitting and receiving antennas is particularly critical.

Therefore, how to balance the emission efficiency and reception efficiency of silicon-based optical phased array lidar system optical chips has become a key issue that needs to be solved urgently.

technical problem

The purpose of the embodiments of the present application is to provide an optical antenna and an optical chip for a phased array laser radar to solve the problem of the existing silicon-based optical phased array laser radar system optical chip that cannot take into account both the emission efficiency and the reception efficiency. question.

Technical solutions

In order to achieve the above purpose, the technical solution adopted in this application is:

Provide an optical antenna, including a transmitting antenna array and a receiving antenna array;

Wherein, the transmitting antenna array includes a plurality of transmitting antenna units for emitting laser beams, and each of the transmitting antenna units has a length; the receiving antenna array includes a plurality of receiving antenna units for receiving laser echoes, Each of the receiving antenna elements has a length;

Moreover, the length dimension of the transmitting antenna unit is greater than the length dimension of the receiving antenna unit.

In one embodiment, the transmitting antenna units are arranged in sequence along the first direction, and the transmitting antenna units have lengths along the second direction; the receiving antenna units are arranged in sequence along the first direction, and each receiving antenna unit has a length along the first direction. Each has a length along the second direction; wherein the first direction and the second direction are perpendicular to each other.

In one embodiment, the number of receiving antenna arrays is greater than the number of transmitting antenna arrays;

A plurality of receiving antenna arrays are arranged on multiple sides or one side of the transmitting antenna array.

In one embodiment, the distance between the receiving antenna array and the transmitting antenna array along the first direction is no less than two adjacent receiving antenna units or two adjacent transmitting antenna units along the first direction. Spacing in one direction; wherein the spacing between adjacent receiving antenna units in the receiving antenna array corresponds to the spacing between adjacent transmitting antenna units in the transmitting antenna array.

In one embodiment, the distance between the receiving antenna array and the transmitting antenna array along the first direction is no greater than the distance between two adjacent receiving antenna units or two adjacent transmitting antenna units along the first direction. 5 times the spacing in one direction.

In one embodiment, the total length of multiple receiving antenna arrays located on the same side of the transmitting antenna array is greater than or equal to the length of the transmitting antenna array.

In one embodiment, the number of receiving antenna arrays is m times the number of transmitting antenna arrays, and m is a positive integer.

In one embodiment, the number of receiving antenna arrays is n, where n≥4;

Wherein, n receiving antenna arrays are arranged on opposite sides of the transmitting antenna array;

Wherein, when n is an odd number, the number of receiving antenna arrays located on one side of the transmitting antenna array is (n+1)/2, and the number of receiving antenna arrays located on the other side of the transmitting antenna array opposite to the one side is The number of receiving antenna arrays 50 is (n-1)/2;

When n is an even number, the number of receiving antenna arrays located on opposite sides of the transmitting antenna array is n/2.

In one embodiment, the transmitting antenna array and the receiving antenna array of the optical antenna are integrated or separated.

In one embodiment, the distance between the receiving antenna array and the transmitting antenna array along the first direction is no less than two adjacent receiving antenna units or two adjacent transmitting antenna units along the first direction. spacing in one direction.

In one embodiment, the spacing between two adjacent receiving antenna units in the receiving antenna array is the same or different;

The spacing between two adjacent transmitting antenna units in the transmitting antenna array is the same or different.

In one embodiment, the spacing between the receiving antenna array and the transmitting antenna array may be equal or unequal; and the receiving antenna arrays located on opposite sides of the transmitting antenna array are facing each other or staggered one by one. set up.

In one embodiment, along the first direction, a plurality of the receiving antenna arrays are arranged in equal numbers on both sides of the transmitting antenna array; and, along the first direction, a plurality of the receiving antenna arrays They are symmetrically arranged on both sides of the transmitting antenna array at equal intervals.

In one embodiment, the size parameters of each receiving antenna unit in the receiving antenna array are the same or different.

Another object of the present application is to provide an optical chip for a phased array lidar, including the optical antenna as described above, an input coupler, a beam splitter, a first phase modulator, and a plurality of second phase modulators. and a first beam combiner; the input coupler, beam splitter, and first phase modulator are connected in sequence to the transmitting antenna array of the optical antenna; the receiving transmitting antenna array of the optical antenna is connected to the second phase The modulator and combiner are connected in sequence; among them,

The input coupler is used to couple the laser beam to the optical chip;

The beam splitter is used to split the laser beam coupled into the optical chip into multiple laser beams;

The first phase modulator is used to adjust the phase of the laser split beam;

The transmitting antenna array is used to emit the phase-adjusted laser beam into space; the laser beam hits the target to form a laser echo;

The receiving antenna is used to receive laser echo;

The second phase modulator is used to adjust the phase of the laser echo;

The beam combiner is used to combine the phase-adjusted laser echoes so that the combined laser echoes are received by the detector.

beneficial effects

The beneficial effects of the optical antenna provided by this application are:

In the optical antenna provided by this application, the length dimension of the transmitting antenna unit is larger than the length dimension of the receiving antenna unit. The transmitting antenna array emits the detection beam to the detection area for detection. After the detection is completed, the laser echo reflected back appears in the form of a light spot, which covers the transmitting antenna array and the receiving antenna array. The higher the reception efficiency of the laser echo, the higher the detection accuracy, and the higher the reception efficiency, the less laser echo is reflected back to the detection area. Compared with the solution in which the lengths of the antenna units of both the transmitting antenna array and the receiving antenna array are the same, the length of the antenna unit of the receiving antenna array is smaller than the length of the transmitting antenna unit. Since the length of the antenna unit of the receiving antenna array is smaller, then the length of the antenna unit of the receiving antenna array is smaller. The laser echo is reflected back to the detection area as little as possible, which improves the reception efficiency of the laser echo.

The beneficial effects of the optical chip of the phased array lidar provided by this application compared to the existing technology are the same as the beneficial effects of the optical antenna provided by this application compared to the existing technology, and will not be described again here.

Description of the drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the description of the embodiments or exemplary technologies will be briefly introduced below. Obviously, the drawings in the following description are only for the purpose of the present application. For some embodiments, for those of ordinary skill in the art, other drawings can be obtained based on these drawings without exerting creative efforts.

Figure 1 is a schematic diagram of an integrated transceiver optical chip provided by an embodiment of the present application;

Figure 2 is a schematic layout diagram of a transmitting antenna array and a receiving antenna array provided by an embodiment of the present application;

Figure 3 is a schematic layout diagram of a transmitting antenna array and a receiving antenna array provided by yet another embodiment of the present application;

Figure 4 is a schematic layout diagram of a transmitting antenna array and a receiving antenna array provided by another embodiment of the present application.

Among them, each figure in the figure is marked with:

10. Input coupler; 20. Beam splitter; 30. First phase modulator; 40. Transmitting antenna array; 50. Receiving antenna array; 60. Second phase modulator; 70. First beam combiner; 80. Second beam combiner; 90. Output coupler.

Embodiments of the invention

In order to make the technical problems, technical solutions and beneficial effects to be solved by this application more clear, this application will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present application and are not used to limit the present application.

It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

It should be understood that the terms "length", "width", "top", "bottom", "front", "back", "left", "right", "vertical", "horizontal", "top" The orientations or positional relationships indicated by , "bottom", "inner", "outer", etc. are based on the orientations or positional relationships shown in the drawings. They are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply what is meant. Devices or elements must have a specific orientation, be constructed and operate in a specific orientation and therefore are not to be construed as limiting.

In addition, the terms “first” and “second” are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of indicated technical features. Therefore, features defined as "first" and "second" may explicitly or implicitly include one or more of these features. In the description of this application, "plurality" means two or more than two, unless otherwise explicitly and specifically limited.

Now, the optical antenna and the optical chip of the phased array lidar provided by the embodiments of the present application will be described.

Referring to FIG. 1 , an optical antenna provided by an embodiment of the present application includes a transmitting antenna array 40 and a receiving antenna array 50 .

Wherein, the transmitting antenna array 40 includes at least one transmitting antenna unit for transmitting a laser beam, and each transmitting antenna unit has a length. The receiving antenna array 50 includes a plurality of receiving antenna units for receiving laser echoes, and each receiving antenna unit has a length. Wherein, the length dimension of the transmitting antenna unit is greater than the length dimension of the receiving antenna unit.

It should be noted that, under normal circumstances, the antenna length in the transmitting antenna array in the embodiment of the present application also needs to be set taking into account the detection purpose. The detection purpose may be related to the detection distance. As the length of the transmitting antenna unit in the transmitting antenna array increases, its transmitting efficiency increases accordingly.

In the optical antenna provided by the embodiment of the present application, the length of the transmitting antenna unit is longer than that of the receiving antenna unit. The transmitting antenna array 40 emits the detection beam to the detection area for detection. After the detection is completed, the laser echo is reflected back, and the laser echo is received by the optical antenna. Since the receiving antenna array in the optical antenna is composed of relatively short antenna units, it can It is understood that a shorter antenna array can more flexibly match the laser echo, which is conducive to increasing the effective receiving area of the laser echo, thereby improving the receiving efficiency of the receiving antenna. In addition, the smaller length of the receiving antenna array will also reduce the laser echo being reflected back to the detection area after being received, which will further improve the receiving efficiency of the antenna.

In the embodiment of this application, the length of the antenna unit in the transmitting antenna array needs to reach a set length. For example, when the antenna unit is selected to be a silicon antenna, its length range can be set to within 1 mm; for example, the antenna unit is selected to be nitrided. When using a silicon material antenna, its length range can be set within 4mm.

It should be understood that in the optical antenna provided by the embodiments of the present application, in order to improve the echo reception efficiency, the overall size of the receiving antenna array can be increased. How the size of the receiving antenna array is specifically limited can be based on the detection purpose and/or the characteristics of the transmitting antenna. Adjust settings and other factors.

Optionally, in this embodiment of the present application, the overall size of the receiving antenna array needs to be larger than the overall size of the transmitting antenna array, and the overall size of the receiving antenna array can be converted accordingly to the size corresponding to a single receiving antenna unit. Specifically, the overall size of the receive antenna array refers to the overall size of each receive antenna unit and the overall size of the spacing between adjacent receive antenna units, that is, the overall size of the receive antenna array is approximately the size of all receive antennas in the receive antenna array The overall dimensions of the unit and the sum of the overall dimensions of all bays.

Optionally, the parameters of the receiving antenna units in each receiving antenna phased array may be the same or different. Considering that the process is simple and easy to implement and taking into account the factors of enhancing reception efficiency, it can be considered that the parameters of the receiving antenna units in each receiving antenna phased array are the same, but the length of the receiving antenna unit is kept relatively short as much as possible to facilitate the adjustment of the receiving antenna. The location makes effective use of the space occupied by the antenna.

Of course, it is understandable that when the length of the receiving antenna is too short, the receiving efficiency of a single receiving antenna unit may also be reduced. Therefore, the specific length of the receiving antenna unit can be comprehensively considered based on the specific circumstances during production.

Alternatively, the overall size of the receiving antenna array may be m times that of the transmitting antenna array, where m≥1. In one embodiment, in order to reduce the manufacturing difficulty and improve the coordination of the system, the receiving antenna array 50 and the transmitting antenna array 40 may have the same parameters except for the length of the antennas.

In one embodiment, the number of receiving antenna arrays 50 is greater than the number of transmitting antenna arrays 40, the transmitting antenna units are arranged sequentially along the first direction, and the transmitting antenna units have lengths along the second direction. The receiving antenna units are arranged sequentially along the first direction, and each receiving antenna unit has a length along the second direction. Wherein, the first direction and the second direction are perpendicular to each other.

In this embodiment, the number of receiving antenna arrays 50 is greater than the number of transmitting antenna arrays 40, and the length of the transmitting antenna unit is greater than the length of the receiving antenna unit. In this way, by using the longer transmitting antenna in the optical antenna to improve the transmitting efficiency and setting up a large number of receiving antenna arrays 50 at the same time, using a shorter antenna to receive the laser echo can reflect the received laser echo as little as possible. to the detection area to improve the reception efficiency of laser echo. In this embodiment, the number of transmitting antenna arrays 40 may be one or more.

In the following embodiments, some specific designs of the above-mentioned optical antennas for both transceiver and transceiver purposes are provided to achieve the above-mentioned improvement of transmission efficiency while reducing re-reflection of the receiving antenna.

In one embodiment, the number of transmitting antenna arrays 40 is one, the number of receiving antenna arrays 50 is greater than the number of transmitting antenna arrays 40 , and multiple receiving antenna arrays 50 are arranged on multiple sides or one side of the transmitting antenna array 40 . For example, the number of transmitting antenna arrays 40 is one, and the number of receiving antenna arrays 50 is two or more.

Of course, it can be understood that the number of transmitting antenna arrays 40 may also be multiple, and the number of receiving antenna arrays 50 needs to be greater than the number of transmitting antenna arrays. For example, the number of transmitting antenna arrays 40 is 2, the number of receiving antenna arrays 50 is 3 or 4, the number of transmitting antenna arrays 40 is 3, and the number of receiving antenna arrays 50 is 4.

In one embodiment, multiple receiving antenna arrays 50 may be arranged around the periphery of the transmitting antenna array 40 . The periphery will be described in detail through the following examples.

In a specific embodiment, multiple receiving antenna arrays 50 may be arranged on four sides of the transmitting antenna array 40, where the positions of the four sides may be symmetrical, or the positions of the four sides may be Randomly selected. For example, the four sides include two sides that are symmetrical about the central axis of the transmitting antenna unit along its length direction, and two sides that are symmetrical about the central axis of the transmitting antenna unit along its width direction, that is, they are arranged on the transmitting antenna unit. Among the four sides of the antenna array 40, the length direction and the width direction are perpendicular to each other.

For example, the upper and lower sides, and the left and right sides of the transmitting antenna array 40 in FIG. 1 . Of course, the number of receiving antenna arrays 50 located on the four sides may be the same or different.

In a specific embodiment, multiple receiving antenna arrays 50 may be arranged on three sides of the transmitting antenna array 40, wherein two of the three sides may be symmetrical and the other may be located on the two symmetrical sides. The middle area, or 3 sides are randomly selected. For example, three sides include two sides that are symmetrical about the central axis of the transmitting antenna unit along its length direction, and one side located at the end of the central axis. Alternatively, the three sides are two sides that are symmetrical to the central axis of the transmitting antenna unit along its width direction, and one side located at the end of the central axis.

For example, the upper side, lower side, and left side of the transmitting antenna array 40 in FIG. 1 . Or, as shown in FIG. 1, the upper and lower sides, and the right side of the transmitting antenna array 40. Or, as shown in FIG. 1 , the left side, the right side, and the upper side of the transmitting antenna array 40 . Or, as shown in FIG. 1 , the left side, the right side, and the lower side of the transmitting antenna array 40 . Of course, the number of receiving antenna arrays 50 located on the three sides may be the same or different.

In a specific embodiment, multiple receiving antenna arrays 50 may be arranged on two sides of the transmitting antenna array 40, where the two sides may be arranged symmetrically, diagonally opposite, or located at different orientations but mutually opposite to each other. adjacent. For example, the two sides may be two sides that are symmetrical about the central axis of the transmitting antenna unit along its length direction, they may be two sides that are symmetrical about the central axis of the transmitting antenna unit along its width direction, or they may be located at the transmitting antenna unit. The side of one side of the central axis of the antenna unit along its length direction and the side of one side of the central axis of the transmitting antenna unit along its width direction.

For example, the upper and lower sides of the transmitting antenna array 40 in FIG. 1 . Or, as shown in FIG. 1 , the left side and the right side of the transmitting antenna array 40 . Or, as shown in FIG. 1, the upper side and the right side of the transmitting antenna array 40. Or, as shown in FIG. 1, the lower side and the left side of the transmitting antenna array 40. Of course, the number of receiving antenna arrays 50 located on the two sides may be the same or different. In the embodiment of the present application, it is preferred that the receiving antenna array 50 is arranged on both sides of the transmitting antenna array 40 along the first direction.

In a specific embodiment, multiple receiving antenna arrays 50 may be arranged on one side of the transmitting antenna array 40 . For example, one side may be a side located on one side of the central axis of the transmitting antenna unit along its length direction, or a side located on one side of the central axis of the transmitting antenna unit along its width direction.

For example, the upper side or lower side of the transmitting antenna array 40 in FIG. 1 . Or, as shown in FIG. 1 , the left side or the right side of the transmitting antenna array 40 . Of course, the number of receiving antenna arrays 50 located on one side can be freely arranged. When multiple receiving antenna arrays 50 are arranged on one side of the transmitting antenna array 40, a single row or multiple rows of receiving antenna arrays 50 may be arranged on one side of the transmitting antenna array 40.

For example, the multiple receiving antenna arrays 50 are disposed above or below the transmitting antenna array 40 as shown in FIG. 1 . The multiple receiving antenna arrays 50 may be arranged at intervals along the second direction. The multiple receiving antenna arrays 50 may be arranged at intervals along the first direction. It may also include multiple receiving antenna arrays 50 that are spaced apart in sequence along the second direction, and multiple receiving antenna arrays 50 that are spaced apart in sequence along the first direction, thereby forming a matrix of receiving antenna arrays 50 .

In one embodiment, the number of transmitting antenna arrays 40 is multiple, and the number of receiving antenna arrays 50 is greater than the number of transmitting antenna arrays 40 . The plurality of receiving antenna arrays 50 are arranged on multiple sides or one side of the transmitting antenna array 40 . The plurality of transmitting antenna arrays 40 may be arranged in an array, such as being sequentially spaced along a first direction and/or being sequentially spaced along a second direction, while the plurality of receiving antenna arrays 50 are arranged on multiple sides or one side of a single transmitting antenna array 40 .

For example, as shown in FIG. 4 , the number of transmitting antenna arrays 40 is 2, and the number of receiving antenna arrays 50 is 9. The two transmitting antenna arrays 40 are sequentially spaced along the second direction. One receiving antenna array 50 can be provided, and four receiving antenna arrays 50 are arranged in equal numbers on both sides of one of the transmitting antenna arrays 40 along the first direction, and the other four receiving antenna arrays 50 are arranged in equal numbers along the first direction. on both sides of another transmitting antenna array 40.

In the embodiment of the present application, the distance along the first direction between the receiving antenna array 50 and the transmitting antenna array 40 is not less than the distance along the first direction between two adjacent receiving antenna units or two adjacent transmitting antenna units. The spacing between adjacent receiving antenna units in the receiving antenna array 50 corresponds to the spacing between adjacent transmitting antenna units in the transmitting antenna array 40. This correspondence can maintain the consistency of other parameters of the transmitting and receiving arrays except for length. , and the spacing between the receiving antenna array 50 and the transmitting antenna array 40 along the first direction is not less than the spacing between two adjacent receiving antenna units or two adjacent transmitting antenna units along the first direction, which can prevent the generation of light between the antenna units. crosstalk.

The spacing between adjacent receiving antenna units in the receiving antenna array 50 is not necessarily equal, and the spacing between adjacent transmitting antenna units in the transmitting antenna array 40 is not necessarily equal, but the spacing between adjacent receiving antenna units in the receiving antenna array 50 is not necessarily equal. The spacing between the antenna units corresponds to the spacing between adjacent transmitting antenna units in the transmitting antenna array 40 . That is to say, the antenna units can be equally spaced or unequally spaced.

In one embodiment, the total length of the multiple receiving antenna arrays 50 located on the same side of the transmitting antenna array 40 is greater than or equal to the length of the transmitting antenna array 40 . Optionally, the number of receiving antenna arrays 50 is m times the number of transmitting antenna arrays 40 to further improve the reception rate of laser echoes. For example, the number of transmitting antenna arrays is 2, and the number of receiving antenna arrays is 4.

In a more preferred embodiment, the number of receiving antenna arrays 50 is n, where n is a positive integer, and n≥4; wherein, n receiving antenna arrays 50 are arranged on opposite sides of the transmitting antenna array 40 .

Wherein, when n is an odd number, the number of receiving antenna arrays 50 located on one side of the transmitting antenna array 40 is (n+1)/2, and the number of receiving antennas located on the other side of the transmitting antenna array 40 opposite to the one side is The number of arrays 50 is (n-1)/2.

For example, as shown in FIG. 2 , the number of receiving antenna arrays 50 is five. The five receiving antenna arrays 50 are arranged on opposite sides of the transmitting antenna array 40 along the first direction. Two of them can be arranged on one side. The number of receiving antenna arrays 50 on one side is half of its total number, while three can be arranged on the other side, and the number of receiving antenna arrays 50 on this side is greater than half of its total number. In this way, the plurality of receiving antenna arrays 50 can be arranged on the sides of the transmitting antenna array 40 in a relatively uniform manner as much as possible, so as to receive laser echoes with higher efficiency.

Wherein, when n is an even number, the number of receiving antenna arrays 50 located on opposite sides of the transmitting antenna array 40 is n/2.

For example, as shown in FIG. 3 , the number of receiving antenna arrays 50 is four, and the four receiving antenna arrays 50 are arranged in equal numbers on opposite sides of the transmitting antenna array 40 along the first direction. The receiving antenna arrays 50 on the same side The quantity is half of its total quantity.

In the embodiment of the present application, the transmitting antenna array 40 and the receiving antenna array 50 in the optical antenna are integrated or separated. Among them, the split type means that the transmitting antenna array 40 and the receiving antenna array 50 are arranged on separate bases, and the integrated type means that the transmitting antenna array 40 and the receiving antenna array 50 are arranged on the same base. For example, the base body can be selected as an optical chip, and the transmitting antenna array 40 and the receiving antenna array 50 can be disposed on the optical chip.

In the embodiment of the present application, the spacing between the receiving antenna array 50 and the transmitting antenna array 40 may be equal or unequal, and the receiving antenna arrays 50 provided on opposite sides of the transmitting antenna array 40 may be directly opposite or disposed one by one.

Taking the orientation as shown in FIG. 1 as an example, the spacing between the receiving antenna array 50 and the transmitting antenna array 40 along the first direction may be equal or unequal, some may be slightly farther away from the transmitting antenna array 40, and some may be slightly closer to the transmitting antenna array 40. Antenna array 40.

Taking the orientation shown in FIG. 1 as an example, the receiving antenna arrays 50 provided on the upper and lower sides of the transmitting antenna array 40 can be arranged facing each other, that is, the number is equal and the receiving antenna arrays 50 are arranged symmetrically. It is also possible that the receiving antenna arrays 50 provided on the upper and lower sides of the transmitting antenna array 40 can be staggered. For example, when the numbers are equal, the multiple receiving antenna arrays 50 on the upper side are arranged in sequence along the second direction with a smaller spacing, while the receiving antenna arrays 50 on the lower side are arranged in a staggered position. The plurality of receiving antenna arrays 50 are arranged in sequence with a relatively large spacing along the second direction. For example, when the numbers are unequal, the multiple receiving antenna arrays 50 on the same side with a larger number are arranged in sequence along the second direction with smaller spacing, while the multiple receiving antenna arrays 50 on the same side with a smaller number are arranged in sequence along the second direction. The spacing of the arrangement is larger.

In a preferred embodiment of the present application, a plurality of receiving antenna arrays 50 are arranged in equal numbers on both sides of the transmitting antenna array 40 along the above-mentioned first direction. Further preferably, along the above-mentioned first direction, multiple receiving antenna arrays 50 are symmetrically arranged on both sides of the transmitting antenna array 40 at equal intervals, so as to receive the laser echo in the largest area and improve the integration of the optical antenna. .

Another object of the embodiments of the present application is to provide an optical chip for an optical phased array laser radar. The optical chip of the optical phased array laser radar includes an input coupler 10, a beam splitter 20, a plurality of first phase modulators 30 and the above-mentioned transmitting antenna array 40. A phase modulator 30 and the transmitting antenna array 40 are optically connected through the optical waveguide base layer in turn.

Among them, the input coupler 10 is used to couple the laser beam to the optical waveguide base layer. The beam splitter 20 is used to split the laser beam coupled to the optical waveguide substrate into a plurality of laser beams. The plurality of first phase modulators 30 are in one-to-one correspondence with the plurality of laser beams, and are used to phase modulate the laser beams. The plurality of transmitting antenna units correspond to the plurality of first phase modulators 30 in a one-to-one manner, and are used to receive the plurality of laser beams modulated by the phase modulators and to transmit the plurality of laser beams to the detection area.

Specifically, the input coupler 10 is used to couple the laser beam from the front end to the optical waveguide base layer, that is, into the optical chip. The first phase modulator 30 is used to phase modulate the laser beams. The phase modulation includes modulating the phases of the multiple laser beams to be consistent, that is, making the phase difference of the multiple laser beams zero, and adjusting the multiple laser beams. The angle of the split beams is adjusted so that multiple laser split beams can be emitted from different angles. Further, the lengths from the beam splitter 20 to the optical waveguide base layer in front of each transmitting antenna unit are equal to achieve an equal optical path effect through the physical structure to ensure that the beam phase difference in front of the transmitting antenna array 40 is zero.

The optical chip of the optical phased array lidar also includes the above-mentioned receiving antenna array 50, a plurality of second phase modulators 60 and a first beam combiner 70. The receiving antenna array 50, a plurality of second phase modulators 60 and the first combiner 70 are The beamer 70 sequentially connects the optical paths through the optical waveguide base layer.

Among them, a plurality of second phase modulators 60 correspond to a plurality of receiving antenna units one-to-one, and are used to phase modulate the laser echo. The first beam combiner 70 is used to coherently combine multiple phase-modulated laser echoes, and transmit the combined laser echoes to the coherent beam combining structure.

Specifically, the second phase modulator 60 is used to phase modulate the laser echo. The phase modulation includes modulating the phases of multiple laser echoes to be consistent, that is, making the phase difference of the multiple laser echoes zero, so as to achieve Multiple laser echoes are coherently superimposed before reaching the second beam combiner 80 . Furthermore, the length from each receiving antenna unit to the optical waveguide base layer before the first beam splitter 20 is equal to achieve an equal optical path effect through the physical structure to ensure that the beam phase difference before the second beam combiner 80 is zero.

Wherein, the coherent beam combiner structure includes a second beam combiner 80 and an output coupler 90. The plurality of first beam combiners 70 are optically connected to the second beam combiner 80 through the optical waveguide base layer. The second beam combiner 80 and The output coupler 90 performs optical path connection through the optical waveguide base layer.

The second beam combiner 80 is used to coherently combine the laser echoes transmitted by the plurality of first beam combiners 70 . The output coupler 90 is used to couple the laser echo coherently combined by the second beam combiner 80 out of the optical waveguide base layer. Specifically, the output coupler 90 is used to coherently combine the laser echoes transmitted by the plurality of first beam combiners 70 and couple them to the optical waveguide base layer, that is, to couple out the optical chip.

In this embodiment, along the second direction, the input coupler 10, the beam splitter 20, the plurality of first phase modulators 30, the transmitting antenna array 40, the second beam combiner 80 and the output coupler 90 are linearly arranged in sequence; Wherein, a plurality of first phase modulators 30 are arranged sequentially along the first direction. In the orientation shown in Figure 1, the input coupler 10, the beam splitter 20, and the plurality of first phase modulators 30 are arranged on the left side of the optical phased array transmitting structure, while the second beam combiner 80 and the output The coupler 90 is arranged on the right side of the optical phased array emission structure.

In this way, the input coupler 10, the beam splitter 20, the plurality of first phase modulators 30, the transmitting antenna array 40, the second beam combiner 80 and the output coupler 90 are linearly arranged along the second direction, and the plurality of optical phase control The array receiving structures are arranged in equal numbers on both sides of the transmitting antenna array 40 along the first direction. Each component of the transmitting antenna array 40 is arranged in an orderly manner with the transmitting antenna array 40 as the center. On the basis of increasing the effective receiving area of the optical antenna, the light Chip integration level.

It should be understood that the transmitting antenna array includes at least one transmitting optical phased array, and one transmitting optical phased array includes multiple transmitting antenna units. Similarly, the receiving antenna array includes at least one receiving optical phased array, and one receiving optical phased array includes multiple receiving antenna units.

Optionally, in the transmitting optical phased array, the optical path difference between the light after splitting and before each antenna array is the same, and the receiving echo enters each receiving optical phased array antenna array and before the beam combining of each receiving optical phased array. The optical path differences are equal, and the optical path differences are equal after each receiving optical phased array is combined and before all receiving optical phased arrays are combined.

Further, in the transmitting antenna array, a phase modulator is connected in front of each transmitting optical antenna unit. In the receiving antenna array, a phase modulator is also connected in front of each receiving optical antenna unit. Each receiving optical phased array is connected to a phase modulator for phase modulation.

It should be noted that in the embodiment of the present application, the transmitting optical phased array mentioned includes at least one transmitting antenna unit and a corresponding phase modulator. The transmitting optical phased array may include a plurality of transmitting antenna units and a plurality of phase modulators arranged in one-to-one correspondence with the plurality of transmitting antenna units.

The mentioned receiving optical phased array includes at least one receiving antenna unit and a corresponding phase modulator. The receiving optical phased array may include multiple receiving antenna units and multiple phase modulators arranged in one-to-one correspondence with the multiple receiving antenna units.

The above are only preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application shall be included in the protection of the present application. within the range.

Claims (15)

1. An optical antenna characterized by:

   Including transmitting antenna array and receiving antenna array;

   Wherein, the transmitting antenna array includes a plurality of transmitting antenna units for emitting laser beams, and each of the transmitting antenna units has a length; the receiving antenna array includes a plurality of receiving antenna units for receiving laser echoes, Each of the receiving antenna elements has a length;

   Wherein, the length dimension of the transmitting antenna unit is greater than the length dimension of the receiving antenna unit.
2. The optical antenna according to claim 1, characterized in that:

   The transmitting antenna units are arranged in sequence along the first direction, and the transmitting antenna units have lengths along the second direction; the receiving antenna units are arranged in sequence along the first direction, and each of the receiving antenna units has a length along the second direction. has a length; wherein the first direction and the second direction are perpendicular to each other.
3. The optical antenna according to claim 1 or 2, characterized in that:

   The number of receiving antenna arrays is greater than the number of transmitting antenna arrays;

   A plurality of receiving antenna arrays are arranged on multiple sides or one side of the transmitting antenna array.
4. The optical antenna according to claim 2, characterized in that:

   The distance between the receiving antenna array and the transmitting antenna array along the first direction is not less than the distance between two adjacent receiving antenna units or two adjacent transmitting antenna units along the first direction; Wherein, the spacing between adjacent receiving antenna units in the receiving antenna array corresponds to the spacing between adjacent transmitting antenna units in the transmitting antenna array.
5. The optical antenna according to claim 4, characterized in that:

   The distance between the receiving antenna array and the transmitting antenna array along the first direction is no greater than the distance between two adjacent receiving antenna units or two adjacent transmitting antenna units along the first direction. 5 times.
6. The optical antenna according to any one of claims 3-5, characterized in that:

   The total length of multiple receiving antenna arrays located on the same side of the transmitting antenna array is greater than or equal to the length of the transmitting antenna array.
7. The optical antenna according to any one of claims 2-6, characterized in that:

   The number of receiving antenna arrays is m times the number of transmitting antenna arrays, and m is a positive integer.
8. The optical antenna according to any one of claims 2-7, characterized in that:

   The number of receiving antenna arrays is n, where n≥4;

   Wherein, n receiving antenna arrays are arranged on opposite sides of the transmitting antenna array;

   Wherein, when n is an odd number, the number of receiving antenna arrays located on one side of the transmitting antenna array is (n+1)/2, and the number of receiving antenna arrays located on the other side of the transmitting antenna array opposite to the one side is The number of receiving antenna arrays 50 is (n-1)/2;

   When n is an even number, the number of receiving antenna arrays located on opposite sides of the transmitting antenna array is n/2.
9. The optical antenna according to any one of claims 1-8, characterized in that:

   In the optical antenna, the transmitting antenna array and the receiving antenna array are integrated or split.
10. The optical antenna according to any one of claims 2 and 4-8, characterized in that:

    The distance between the receiving antenna array and the transmitting antenna array along the first direction is no less than the distance between two adjacent receiving antenna units or two adjacent transmitting antenna units along the first direction.
11. The optical antenna according to any one of claims 1-10, characterized in that:

    The spacing between two adjacent receiving antenna units in the receiving antenna array is the same or different;

    The spacing between two adjacent transmitting antenna units in the transmitting antenna array is the same or different.
12. The optical antenna according to any one of claims 1-11, characterized in that:

    The spacing between the receiving antenna array and the transmitting antenna array may be equal or unequal;

    Wherein, the receiving antenna arrays located on opposite sides of the transmitting antenna array are arranged to face each other or be offset one by one.
13. The optical antenna according to any one of claims 4-8 and 10, characterized in that:

    Along the first direction, a plurality of receiving antenna arrays are arranged in equal numbers on both sides of the transmitting antenna array; wherein, along the first direction, a plurality of receiving antenna arrays are symmetrically arranged at equal intervals. on both sides of the transmitting antenna array.
14. The optical antenna according to claim 13, characterized in that:

    The size parameters of each receiving antenna unit in the receiving antenna array are the same or different.
15. An optical chip for phased array laser radar, which is characterized by:

    Comprising an optical antenna as claimed in any one of claims 1 to 14, as well as an input coupler, a beam splitter, a first phase modulator, a plurality of second phase modulators and a first beam combiner; the input coupler , the beam splitter, and the first phase modulator are connected in sequence to the transmitting antenna array of the optical antenna; the receiving antenna array of the optical antenna is connected to the second phase modulator and the beam combiner in sequence; wherein,

    The input coupler is used to couple the laser beam to the optical chip;

    The beam splitter is used to split the laser beam coupled into the optical chip into multiple laser beams;

    The first phase modulator is used to adjust the phase of the laser split beam;

    The transmitting antenna array is used to emit the phase-adjusted laser beam into space; the laser beam hits the target to form a laser echo;

    The receiving antenna is used to receive laser echo;

    The second phase modulator is used to adjust the phase of the laser echo;

    The beam combiner is used to combine the phase-adjusted laser echoes so that the combined laser echoes are received by the detector.