Optical antenna, chip, phased array laser radar and detection method

Abstract

The embodiment of the present invention provides an optical antenna, a chip, a phased array laser radar and a detection method. The optical antenna includes: an SOI substrate, two groups of waveguide arrays, two groups of pattern spot converters, a silicon plate, a two-dimensional grating array and a protective layer; the SOI substrate includes two groups of waveguide arrays, two groups of pattern spot converters and a silicon plate; a two-dimensional grating array is formed on the silicon plate, and the protective layer is located above the two groups of waveguide arrays, the two groups of pattern spot converters and the two-dimensional grating array; the two groups of waveguide arrays are respectively connected to the corresponding pattern spot converter optical paths, and the two groups of pattern spot converters are respectively connected to the two-dimensional grating array optical paths; the two groups of waveguide arrays are orthogonal to each other, and the two groups of pattern spot converters are orthogonal to each other. When the optical antenna is used as a transmitting antenna, the scanning range is increased. And when the optical antenna is used as a receiving antenna, the receiving effect of the optical signal is greatly improved, thereby improving the detection capability of the phased array laser radar.

Description

Technical Field

[0001] The embodiments of the present invention relate to the field of radar technology, and in particular to an optical antenna, a chip, a phased array laser radar and a detection method. Background Art

[0002] The concept of phased array LiDAR has been proposed for a long time, and various design schemes are also being developed. The basic modules of the current phased array LiDAR chip include: light source module, beam splitting module, phase modulation module and optical antenna module. These modules cooperate to realize the detection function of LiDAR.

[0003] When the optical antenna of the existing phased array laser radar chip is used to transmit light waves, the scanning angle along the grating direction needs to be adjusted by adjusting the wavelength, but the wavelength adjustment capability of conventional semiconductor lasers is very limited, which makes the scanning angle in this direction very small. In addition, when the optical antenna is used to receive light signals, the light signals reflected back in space will be depolarized to a certain extent due to factors such as uneven air temperature or air flow, and the linear polarization characteristics will be weakened, which will greatly reduce the reception effect of the light signal and affect the detection capability of the entire phased array laser radar. Summary of the invention

[0004] The embodiments of the present invention provide an optical antenna, a chip, a phased array laser radar and a detection method, which solve the technical problem in the prior art that the optical antenna has a very small scanning angle and greatly reduces the receiving effect of the optical signal, thereby affecting the detection capability of the entire phased array laser radar.

[0005] In a first aspect, an embodiment of the present invention provides an optical antenna, comprising: an SOI substrate, two groups of waveguide arrays, two groups of pattern spot converters, a silicon plate, a two-dimensional grating array and a protective layer;

[0006] The two groups of waveguide arrays, the two groups of pattern spot converters and the silicon flat plate are included in the SOI substrate; a two-dimensional grating array is formed on the silicon flat plate, and the protective layer covers the two groups of waveguide arrays, the two groups of pattern spot converters and the two-dimensional grating array;

[0007] The two groups of waveguide arrays are respectively connected to the corresponding pattern spot converter optical paths, and the two groups of pattern spot converters are respectively connected to the two-dimensional grating array optical paths;

[0008] The two groups of waveguide arrays are orthogonal to each other, and the two groups of pattern spot converters are orthogonal to each other.

[0009] Further, in the optical antenna as described above, a two-dimensional grating array is etched on the silicon plate, and the two-dimensional grating array is a two-dimensional hole structure array;

[0010] The hole structures in the two-dimensional hole structure array are round holes or square holes.

[0011] Further, in the optical antenna as described above, a spacer layer is provided on the silicon flat plate, a grating material layer is grown on the spacer layer, the two-dimensional grating array is etched on the grating material layer, and the two-dimensional grating array is a two-dimensional columnar array;

[0012] The columns of the two-dimensional column array are round columns or square columns.

[0013] Further, in the optical antenna as described above, the two groups of waveguide arrays include a transverse waveguide array and a longitudinal waveguide array, and the two-dimensional grating array includes: a transverse grating and a longitudinal grating;

[0014] The waveguide spacing in the transverse waveguide array is an integer multiple of the longitudinal grating period, and the waveguide spacing in the longitudinal waveguide array is an integer multiple of the transverse grating period.

[0015] In a second aspect, an embodiment of the present invention provides a transmitting chip of a phased array laser radar, comprising: an input coupler, an optical switch, a first beam splitter, a second beam splitter, a first phase modulator, a second phase modulator, and an optical antenna as described in any one of the first aspects above;

[0016] The input coupler is connected to each beam splitter optical path through the optical switch, each beam splitter is connected to a corresponding phase modulator optical path, and each phase modulator is connected to the optical antenna optical path.

[0017] In a third aspect, an embodiment of the present invention provides a receiving chip of a phased array laser radar, comprising: a detector, a first beam splitter, a second beam splitter, a first phase modulator, a second phase modulator, and an optical antenna as described in any one of the first aspects above;

[0018] The detector is connected to each beam splitter optical path respectively, each beam splitter is connected to the corresponding phase modulator optical path, and each phase modulator is connected to the optical antenna optical path.

[0019] In a fourth aspect, an embodiment of the present invention provides a phased array laser radar, comprising: a transmitting chip of the phased array laser radar as described in the second aspect, and / or, a receiving chip of the phased array laser radar as described in the third aspect.

[0020] In a fifth aspect, an embodiment of the present invention provides a method for transmitting a phased array laser radar, wherein the method adopts the transmitting chip as described in the second aspect, and the method includes:

[0021] The input coupler couples the input light to the transmitting chip;

[0022] The optical switch controls the input light to work in two groups of emission light paths in a time-sharing manner, so as to realize scanning of the corresponding scanning ranges of the two groups of emission light paths.

[0023] Furthermore, in the method as described above, the optical switch controls the input light to work in two groups of emission light paths in a time-sharing manner to achieve scanning of the corresponding scanning ranges of the two groups of emission light paths, including:

[0024] The optical switch controls the input light to pass through the first beam splitter and the first phase modulator, and then pass the light through the transverse waveguide array, while controlling the second beam splitter and the second phase modulator to block the light from passing through the corresponding longitudinal waveguide array;

[0025] The first phase modulator adjusts the angle of the emitted light and the wavelength modulator adjusts the wavelength of the light source to achieve two-dimensional scanning in a first range;

[0026] The optical switch controls the input light to pass through the second beam splitter and the second phase modulator, and then pass light through the longitudinal waveguide array, while controlling the first beam splitter and the first phase modulator to block light from passing through the corresponding transverse waveguide array;

[0027] The second phase modulator adjusts the angle of the emitted light and the wavelength adjuster adjusts the wavelength of the light source to achieve two-dimensional scanning in the second range.

[0028] In a sixth aspect, an embodiment of the present invention provides a receiving method of a phased array laser radar, the method adopting the receiving chip as described in the third aspect, the method comprising:

[0029] Two groups of receiving optical paths in the optical antenna receive the receiving optical signal simultaneously;

[0030] The received optical signals are gathered into a total received optical signal through two groups of receiving optical paths;

[0031] adjusting the voltage of each channel of the two phase modulators according to the light intensity of the received total light signal;

[0032] If the light intensity of the received light total signal is the maximum light intensity, the received light total signal is transmitted to the detector.

[0033] Furthermore, in the above method, if the light intensity of the received total light signal is the maximum light intensity, the method further includes:

[0034] Setting the voltage of each channel corresponding to the maximum light intensity as a phase calibration voltage;

[0035] The phase calibration voltage is called to receive the next received optical signal.

[0036] The embodiment of the present invention provides an optical antenna, a chip, a phased array laser radar and a detection method, wherein the optical antenna comprises: an SOI substrate, two groups of waveguide arrays, two groups of pattern spot converters, a silicon plate, a two-dimensional grating array and a protective layer; two groups of waveguide arrays, two groups of pattern spot converters and a silicon plate are formed in the SOI substrate; a two-dimensional grating array is formed on the silicon plate, and the protective layer is located above the two groups of waveguide arrays, the two groups of pattern spot converters and the two-dimensional grating array; the two groups of waveguide arrays are respectively connected to the corresponding pattern spot converter optical paths, and the two groups of pattern spot converters are respectively connected to the two-dimensional grating array optical paths; the two groups of waveguide arrays are mutually orthogonal, and the two groups of pattern spot converters are mutually orthogonal. Since the two groups of waveguide arrays are mutually orthogonal and the two groups of pattern spot converters are mutually orthogonal, when the optical antenna is used as a transmitting antenna, light is respectively emitted by time-division multiplexing the emission optical paths corresponding to the waveguide arrays in two directions, so as to realize the scanning of the corresponding scanning ranges of the two groups of emission optical paths, thereby increasing the scanning range. When the optical antenna is used as a receiving antenna, the receiving optical paths corresponding to the waveguide arrays in two directions are used to receive optical signals at the same time, so that the light intensity of the received light reaches the strongest and is detected by the detector. This can effectively reduce the influence of depolarization and linear polarization of the received optical signal in space, greatly improve the receiving effect of the optical signal, and thus improve the detection capability of the phased array lidar.

[0037] It should be understood that the contents described in the above summary of the invention are not intended to limit the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0039] Figure 1 A schematic diagram of the transverse cross-sectional structure of an optical antenna provided in Embodiment 1 of the present invention;

[0040] Figure 2 A schematic diagram of the SOI substrate structure of an optical antenna provided in Embodiment 1 of the present invention;

[0041] Figure 3 A schematic diagram of a longitudinal cross-sectional structure of an optical antenna provided in Embodiment 2 of the present invention;

[0042] Figure 4 A schematic diagram of a transverse cross-sectional structure of an optical antenna provided in Embodiment 2 of the present invention;

[0043] Figure 5 A schematic diagram of a longitudinal cross-sectional structure of an optical antenna provided in Embodiment 3 of the present invention;

[0044] Figure 6 A schematic diagram of a transverse cross-sectional structure of an optical antenna provided in Embodiment 4 of the present invention;

[0045] Figure 7 A schematic diagram of another transverse cross-sectional structure of an optical antenna provided in Embodiment 4 of the present invention;

[0046] Figure 8 A schematic diagram of another transverse cross-sectional structure of the optical antenna provided in the fourth embodiment of the present invention;

[0047] Fig. 9 A schematic diagram of the structure of a transmitting chip of a phased array laser radar provided in Embodiment 5 of the present invention;

[0048] Fig.10 A schematic diagram of the structure of a receiving chip of a phased array laser radar provided in Embodiment 6 of the present invention;

[0049] Fig.11 A schematic diagram of a flow chart of a method for transmitting a phased array laser radar provided in Embodiment 8 of the present invention;

[0050] Fig.12 A schematic flow chart of step 102 in the method for transmitting a phased array laser radar provided in Embodiment 8 of the present invention;

[0051] Fig.13 A schematic flow chart of a receiving method for a phased array laser radar provided in Embodiment 9 of the present invention.

[0052] Reference numerals:

[0053] 1-input coupler 2-optical switch 3-first beam splitter 4-second beam splitter 5-first phase modulator 6-second phase modulator 7-optical antenna 8-detector 10-bottom silicon layer 20-buried oxide layer 30-top silicon layer 40-protective layer 50-spacer layer 31-waveguide structure layer 311-lateral waveguide array 312-longitudinal waveguide array 313-lateral pattern spot converter 314-longitudinal pattern spot converter 32-grating structure layer 321-silicon plate 322-two-dimensional grating array DETAILED DESCRIPTION

[0054] Embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although certain embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be construed as being limited to the embodiments described herein, which are instead provided for a more thorough and complete understanding of the present invention. It should be understood that the drawings and embodiments of the present invention are only for exemplary purposes and are not intended to limit the scope of protection of the present invention.

[0055] The terms "first", "second", "third", "fourth", etc. (if any) in the description and claims of the embodiments of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present invention described herein, for example, can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0056] The following describes an optical antenna, a transmitting chip, a receiving chip, a phased array laser radar, and a detection method of a phased array laser radar provided in embodiments of the present invention in conjunction with the accompanying drawings.

[0057] Among them, the optical antenna is used to transmit or receive optical signals and can be applied to many optical systems. For example, phased array laser radar. Since there are many bands of light waves, one optical antenna cannot be used for light waves of all bands. Therefore, for the convenience of expression, in each embodiment of the present invention, the technical solution is explained by taking the optical antenna for light waves with a band of 1.5 to 1.6 μm as an example.

[0058] Embodiment 1

[0059] Figure 1 The schematic diagram of the transverse cross-sectional structure of the optical antenna provided in the first embodiment of the present invention is as follows: Figure 1 As shown, the optical antenna provided in this embodiment includes: an SOI substrate, two groups of waveguide arrays, two groups of pattern spot converters, a silicon plate 321, a two-dimensional grating array 322 and a protective layer 40.

[0060] Among them, the SOI substrate includes two groups of waveguide arrays, two groups of spot converters and a silicon flat plate 321; a two-dimensional grating array 322 is formed on the silicon flat plate 321, and a protective layer 40 covers the two groups of waveguide arrays, two groups of spot converters and the two-dimensional grating array 322.

[0061] Specifically, in this embodiment, Figure 2 Schematic diagram of the SOI substrate structure of the optical antenna provided in the first embodiment of the present invention; Figure 2 As shown, the SOI substrate includes: a bottom silicon layer 10, a buried oxide layer 20, and a top silicon layer 30;

[0062] The buried oxide layer 20 is located between the bottom silicon layer 10 and the top silicon layer 30;

[0063] Optionally, in this embodiment, the material and thickness of each layer of the SOI substrate can be customized according to different requirements, so the type and thickness of each layer of material are not limited. A conventional standard CMOS process SOI substrate can also be used. When selecting a conventional standard CMOS process SOI substrate, the material of the bottom silicon layer 10 is silicon, and its thickness is 400 to 800 μm, the material of the buried oxide layer 20 is silicon dioxide, and its thickness is 2 μm, and the material of the top silicon layer 30 is silicon, and its thickness is 220 nm.

[0064] In this embodiment, the top silicon layer 30 of the SOI substrate includes a waveguide structure layer 31 and a grating structure layer 32. The waveguide structure layer 31 mainly includes two groups of waveguide arrays and two groups of pattern spot converters. The grating structure layer 32 includes a silicon plate 321 and a two-dimensional grating array 322 formed on the silicon plate 321.

[0065] The two groups of waveguide arrays are respectively connected to the corresponding spot converter optical paths, and the two groups of spot converters are respectively connected to the two-dimensional grating array 322 optical paths.

[0066] The two groups of waveguide arrays are orthogonal to each other, and the two groups of pattern spot converters are orthogonal to each other.

[0067] In this embodiment, the two groups of waveguide arrays are respectively a transverse waveguide array 311 and a longitudinal waveguide array 312. Correspondingly, the two groups of pattern spot converters are respectively a transverse pattern spot converter 313 and a longitudinal pattern spot converter 314. The transverse pattern spot converter 313 and the longitudinal pattern spot converter 314 are orthogonal to each other. The transverse pattern spot converter 313 and the longitudinal pattern spot converter 314 are orthogonal to each other.

[0068] Specifically, in this embodiment, when the waveguide array is formed on the top silicon layer 30, the thickness of the waveguide in each group of the waveguide array is consistent with the thickness of the top silicon layer 30, which can be 220nm in the embodiment of the present invention. The waveguide can be a TE mode single-mode waveguide, and the shape can be a ridge waveguide or a strip waveguide. The waveguide width corresponding to the central wavelength can be 1550nm or other reasonable values. The TE mode single-mode waveguide is generally 450-500nm, and can be set to 500nm in this embodiment.

[0069] It is understandable that the spacing and waveguide width of the waveguides in the transverse waveguide array 311 and the waveguides in the longitudinal waveguide array 312 may also be different to meet different application requirements.

[0070] Since the size of the waveguide array and the back-end silicon plate 321 are very different, the effective refractive index of the light in the waveguide is very different. If they are directly connected, there will be strong reflection. Therefore, the emission light in the waveguide is gradually changed by the template converter and transmitted to the silicon plate 321, which can effectively reduce the reflection. In order to better transition the emission light from the waveguide in the waveguide array to the silicon plate 321, in one embodiment, the pattern spot converter can use a trapezoidal pattern spot converter, with the short bottom side of the pattern spot converter close to the waveguide and the long bottom side close to the silicon plate 321, so as to reduce the energy loss caused by the mismatch of the front and rear waveguide pattern spots.

[0071] In this embodiment, the silicon plate 321 formed on the top silicon layer 30 of the SOI substrate can be a square silicon plate 321. The specific shape and size of the square silicon plate 321 are not limited and need to be determined according to the structure of the two-dimensional grating array 322. For example, it can be a square or a rectangle.

[0072] When the two-dimensional grating array 322 is formed on the silicon flat plate 321 , the specific forming method is not limited.

[0073] In this embodiment, two mutually orthogonal groups of waveguide arrays, two mutually orthogonal groups of pattern spot converters and silicon flat plate 321 are formed in the top silicon layer of the SOI substrate, and after a two-dimensional grating array 322 is formed on the silicon flat plate 321, a protective layer 40 is disposed above all devices to protect the entire optical antenna. The material of the protective layer 40 is a low refractive index material, whose refractive index is lower than that of the waveguide material, such as silicon can be used as the waveguide material, and the material of the protective layer 40 can be silicon dioxide or other low refractive index materials, which is not limited in this embodiment.

[0074] The optical antenna provided in this embodiment includes: an SOI substrate, two groups of waveguide arrays, two groups of pattern spot converters, a silicon plate 321, a two-dimensional grating array 322 and a protective layer 40; two groups of waveguide arrays, two groups of pattern spot converters and a silicon plate 321 are formed in the SOI substrate; a two-dimensional grating array 322 is formed on the silicon plate 321, and the protective layer 40 is located above the two groups of waveguide arrays, the two groups of pattern spot converters and the two-dimensional grating array 322; the two groups of waveguide arrays are respectively connected to the corresponding pattern spot converter optical paths, and the two groups of pattern spot converters are respectively connected to the two-dimensional grating array 322 optical paths; the two groups of waveguide arrays are mutually orthogonal, and the two groups of pattern spot converters are mutually orthogonal. Since the two groups of waveguide arrays are mutually orthogonal, the two groups of pattern spot converters are mutually orthogonal. When the optical antenna is used as a transmitting antenna, the waveguide array in each direction has a corresponding transmitting optical path. The transmitting optical paths in two directions can be used to transmit light respectively by time-division multiplexing, so as to realize the scanning of the corresponding scanning range of the two sets of transmitting optical paths, thereby increasing the scanning range; when used as a receiving antenna, the receiving optical paths corresponding to the waveguide arrays in two directions can be used to receive optical signals at the same time, which can make the light intensity of the received optical signal reach the strongest, thereby weakening the phenomenon that the optical signal reflected back in the space will be depolarized to a certain extent due to the influence of factors such as uneven air temperature or air flow, and the linear polarization characteristics will be weakened, making it easier for the detector to detect the corresponding target. Therefore, when the optical antenna is used as a transmitting antenna, the scanning range can be increased; when used as a receiving antenna, it can effectively reduce the influence of depolarization and linear polarization of the received optical signal in space, greatly improving the reception effect of the optical signal and improving the detection capability of the phased array laser radar.

[0075] Embodiment 2

[0076] Figure 3 A schematic diagram of a longitudinal cross-sectional structure of an optical antenna provided in Embodiment 2 of the present invention is shown as follows: Figure 3 As shown, the optical antenna provided in this embodiment is a further refinement of the two-dimensional grating array 322 formed on the silicon flat plate 321 based on the optical antenna provided in the first embodiment. The optical antenna provided in this embodiment also includes the following scheme.

[0077] Optionally, in this embodiment, if Figure 3 As shown, in this embodiment, a two-dimensional grating array 322 is etched on a silicon flat plate 321, and the two-dimensional grating array 322 is a two-dimensional hole structure array.

[0078] Specifically, in this embodiment, a two-dimensional hole structure array is etched on the square silicon plate 321, and the two-dimensional hole structure array is used as the two-dimensional grating array 322. Figure 3As shown, the two-dimensional grating array 322 is etched on the square silicon flat plate 321 structure, and its etching depth is determined according to specific needs, which is not limited in this embodiment. In this embodiment, in order to be consistent with most foundry platforms, the etching depth of the two-dimensional grating array 322 can be 70nm.

[0079] In this embodiment, the hole structures in the two-dimensional hole structure array are round holes or square holes. Figure 1 As shown, the hole structure in the two-dimensional grating array 322 is a square hole. Figure 4 A schematic diagram of a transverse cross-sectional structure of an optical antenna provided in Embodiment 2 of the present invention is shown as follows: Figure 4 As shown, the hole structure in the two-dimensional optical array is a circular hole. If the hole structure is a circular hole, the diameter and center distance of the circular hole can be consistent with the design requirements corresponding to the square hole, and the corresponding duty cycle and period can be set according to specific needs.

[0080] Optionally, the transverse grating period and the longitudinal grating period of the two-dimensional grating array 322 are independent, and can be the same or different, and the grating duty cycle is also independent, and can be the same or different, but in order to simplify the device structure, such as Figure 1 and Figure 4 As shown, the period and duty cycle of the transverse and longitudinal gratings in this embodiment are the same.

[0081] The horizontal grating period is the distance between two adjacent horizontal gratings, and the vertical grating period is the distance between two adjacent vertical gratings.

[0082] In the optical antenna provided in this embodiment, a two-dimensional grating array 322 is etched on a silicon flat plate 321. The two-dimensional grating array 322 is a two-dimensional hole structure array; the hole structure in the two-dimensional hole structure array is a circular hole or a square hole. When the two-dimensional grating array 322 can be formed on the silicon flat plate 321, the silicon flat plate is directly etched to form the two-dimensional grating array, and there is no need to set a spacer layer on the silicon flat plate. After a grating material layer is grown on the spacer layer, the two-dimensional grating array is further etched on the grating material layer, thereby reducing the process flow and making it easier and faster to form the two-dimensional grating array 322.

[0083] Embodiment 3

[0084] Figure 5 A schematic diagram of a longitudinal cross-sectional structure of an optical antenna provided in Embodiment 3 of the present invention is shown as follows: Figure 5 As shown, the optical antenna provided in this embodiment is a further refinement of the two-dimensional grating array 322 formed on the silicon flat plate 321 based on the optical antenna provided in the first embodiment. The optical antenna provided in this embodiment also includes the following scheme.

[0085] In this embodiment, a spacer layer 50 is disposed on the silicon flat plate 321 , a grating material layer is grown on the spacer layer 50 , and a two-dimensional grating array 322 is etched on the grating material layer. The two-dimensional grating array 322 is a two-dimensional columnar array.

[0086] Specifically, in this embodiment, a spacer layer 50 can be firstly provided on the square silicon flat plate 321, wherein the spacer layer 50 has a first refractive index. Then a grating material layer is grown on the spacer layer 50. The grating material layer has a second refractive index. Among them, the first refractive index of the spacer layer 50 is lower than the second refractive index of the grating material layer. The difference between the refractive index of the grating material layer and the refractive index of the spacer layer 50 and the protective layer 40 is greater than a preset threshold value, which is obtained through multiple experiments, and the preset threshold value is usually between 0.5 and 2.5. The material of the spacer layer 50 can be silicon dioxide, and the grating material layer can be silicon nitride, silicon oxynitride, polycrystalline silicon and other materials. Finally, a two-dimensional columnar array is etched on the grating material layer, and the two-dimensional columnar array is determined as a two-dimensional grating array 322.

[0087] Among them, Figure 5 As shown, the column shape of the two-dimensional column array is a circular column or a square column. When the column shape of the two-dimensional column array is a circular column, the cross-sectional structure diagram of the optical antenna is similar to Figure 4 The horizontal cross-sectional structure schematic diagram shown is the same. If the column shape is a cylinder, the diameter and center distance of the cylinder can be consistent with the design requirements corresponding to the square column, and the corresponding duty cycle and period can be set according to specific needs.

[0088] Optionally, the transverse grating period and the longitudinal grating period of the two-dimensional grating array 322 are independent, and can be the same or different, and the grating duty cycle is also independent, and can be the same or different, but in order to simplify the device structure, such as Figure 1 and Figure 5 As shown, the period and duty cycle of the transverse and longitudinal gratings in this embodiment are the same.

[0089] In the optical antenna provided in this embodiment, a spacer layer 50 is provided on a silicon flat plate 321, a grating material layer is grown on the spacer layer 50, and a two-dimensional grating array 322 is etched on the grating material layer. The two-dimensional grating array 322 is a two-dimensional columnar array; the column of the two-dimensional columnar array is a cylinder or a square column. Since the material and thickness of the spacer layer 50 and the material and thickness of the grating material layer can be set according to specific needs, compared with the two-dimensional grating array 322 provided in the second embodiment, the design of the two-dimensional grating array 322 has great flexibility.

[0090] Embodiment 4

[0091] Figure 6 A schematic diagram of a transverse cross-sectional structure of an optical antenna provided in Embodiment 4 of the present invention is shown in FIG. Figure 6 As shown, the optical antenna provided in this embodiment is a further refinement of the waveguide array and the two-dimensional grating array 322 on the basis of the optical antenna provided in any one of embodiments one to three. The optical antenna provided in this embodiment also includes the following technical solutions.

[0092] In this embodiment, the two groups of waveguide arrays include a transverse waveguide array 311 and a longitudinal waveguide array 312 , and the two-dimensional grating array 322 includes: a transverse grating and a longitudinal grating.

[0093] Optionally, the waveguide spacing in the transverse waveguide array 311 is an integer multiple of the longitudinal grating period, and the waveguide spacing in the longitudinal waveguide array 312 is an integer multiple of the transverse grating period.

[0094] Specifically, in this embodiment, the waveguide array and the two-dimensional grating array 322 can be designed independently, and it is only necessary to satisfy that the waveguide spacing of the transverse waveguide array 311 is an integer multiple of the longitudinal grating period, and the waveguide spacing of the longitudinal waveguide array 312 is an integer multiple of the transverse grating period. Figure 6 In the figure, the waveguide spacings of the transverse waveguide array 311 and the longitudinal waveguide array 312 are different. The waveguide spacing of the transverse waveguide array 311 corresponds to one longitudinal grating period, and the waveguide spacing of the longitudinal waveguide array 312 corresponds to two transverse grating periods.

[0095] In this embodiment, after ensuring that the waveguide spacing in the transverse waveguide array 311 is an integer multiple of the longitudinal grating period, and the waveguide spacing in the longitudinal waveguide array 312 is an integer multiple of the transverse grating period, it can be ensured that the grating structure corresponding to the front of each transverse waveguide in the transverse waveguide array 311 is the same, and the grating structure corresponding to the front of each longitudinal waveguide in the longitudinal waveguide array 312 is also the same.

[0096] Optionally, in this embodiment, according to different requirements for optical antennas in practical applications, the lateral grating period and the longitudinal grating period of the two-dimensional grating array 322 can be set to be different, or the lateral grating duty cycle and the longitudinal grating duty cycle of the two-dimensional grating array 322 can be set to be different. Figure 7 As shown in FIG. 1 , the horizontal grating period and the vertical grating period are set to be different. Figure 8 As shown, the transverse grating and the longitudinal grating have different duty cycles.

[0097] The optical antenna provided in this embodiment can set the waveguide spacing in the transverse waveguide array 311 to an integer multiple of the longitudinal grating period, and the waveguide spacing in the longitudinal waveguide array 312 to an integer multiple of the transverse grating period according to different requirements for the optical antenna in practical applications. To meet the functional requirements of the coordination between the waveguide and the grating. In addition, the transverse grating period and the longitudinal grating period of the two-dimensional grating array 322 are set to be different, or the transverse grating duty cycle and the longitudinal grating duty cycle of the two-dimensional grating array 322 are set to be different, so that the design of the optical antenna has great flexibility and can meet different application requirements.

[0098] Embodiment 5

[0099] Fig. 9 This is a schematic diagram of the structure of the transmitting chip of the phased array laser radar provided in the fifth embodiment of the present invention, as shown in FIG. Fig. 9 As shown, the transmitting chip of the phased array laser radar provided in this embodiment includes: an input coupler 1, an optical switch 2, a first beam splitter 3, a second beam splitter 4, a first phase modulator 5, a second phase modulator 6 and an optical antenna 7.

[0100] The input coupler 1 is connected to each beam splitter optical path through the optical switch 2 , each beam splitter is connected to the corresponding phase modulator optical path, and each phase modulator is connected to the optical antenna 7 optical path.

[0101] Specifically, in this embodiment, the input coupler 1 is optically connected to the optical switch 2, the optical switch 2 is optically connected to the first beam splitter 3 and the second beam splitter 4 respectively, the first beam splitter 3 is optically connected to the transverse waveguide array path of the optical antenna 7 through the first phase modulator 5, and the second beam splitter 4 is optically connected to the longitudinal waveguide array path of the optical antenna 7 through the second phase modulator 6.

[0102] The first beam splitter 3, the first phase modulator 5 and the transverse waveguide array of the optical antenna 7, the transverse pattern converter and the transverse grating constitute a first group of emission light paths. The second beam splitter 4, the second phase modulator 6 and the longitudinal waveguide array of the optical antenna 7, the longitudinal pattern converter and the longitudinal grating constitute a second group of emission light paths.

[0103] In this embodiment, the structure and function of the optical antenna 7 are the same as the structure and function of the optical antenna in any one of Embodiments 1 to 4 of the present invention, and will not be described in detail here.

[0104] Specifically, in this embodiment, when the transmitting chip of the phased array laser radar transmits light, the input coupler 1 couples the input light to the transmitting chip; the optical switch 2 controls the input light to work in two groups of transmitting light paths in time-sharing manner to achieve scanning of the corresponding scanning ranges of the two groups of transmitting light paths.

[0105] The transmitting chip of the phased array laser radar provided in this embodiment includes: an input coupler 1, an optical switch 2, a first beam splitter 3, a second beam splitter 4, a first phase modulator 5, a second phase modulator 6 and an optical antenna 7; the input coupler 1 is respectively connected to each beam splitter optical path through the optical switch 2, each beam splitter is connected to the corresponding phase modulator optical path, and each phase modulator is connected to the optical path of the optical antenna 7. Since the two groups of waveguide arrays are orthogonal to each other and the two groups of pattern spot converters are orthogonal to each other, when the optical antenna 7 is used as a transmitting antenna, light is respectively emitted by time-division multiplexing the emission optical paths corresponding to the waveguide arrays in two directions, so as to realize the scanning of the corresponding scanning ranges of the two groups of emission optical paths, thereby increasing the scanning range.

[0106] Embodiment 6

[0107] Fig.10 This is a schematic diagram of the structure of a receiving chip of a phased array laser radar provided in Embodiment 6 of the present invention, as shown in FIG. Fig.10 As shown, the receiving chip of the phased array laser radar provided in this embodiment includes: a detector 8, a first beam splitter 3, a second beam splitter 4, a first phase modulator 5, a second phase modulator 6 and an optical antenna 7.

[0108] The detector 8 is respectively connected to the optical path of each beam splitter, each beam splitter is connected to the optical path of the corresponding phase modulator, and each phase modulator is connected to the optical path of the optical antenna 7.

[0109] Specifically, in this embodiment, the transverse grating, transverse pattern converter, transverse waveguide array, first phase modulator 5 and first beam splitter 3 of the optical antenna 7 constitute a first group of receiving optical paths. The longitudinal grating, longitudinal pattern converter, longitudinal waveguide array, second phase modulator 6 and second beam splitter 4 constitute a second group of receiving optical paths.

[0110] In this embodiment, the structure and function of the optical antenna 7 are the same as the structure and function of the optical antenna 7 in any one of Embodiments 1 to 4 of the present invention, and are not described in detail here.

[0111] Specifically, in this embodiment, when the receiving chip of the phased array laser radar is used to receive the received light signal, the two groups of waveguide arrays in the optical antenna 7 receive the received light signal at the same time; the received light signal is converged into a total received light signal through two groups of receiving optical paths; the voltage of each channel of the two phase modulators is adjusted according to the light intensity of the total received light signal; if the light intensity of the total received light signal is the maximum light intensity, the total received light signal is transmitted to the detector 8.

[0112] The receiving chip of the phased array laser radar provided in this embodiment includes: a detector 8, a first beam splitter 3, a second beam splitter 4, a first phase modulator 5, a second phase modulator 6 and an optical antenna 7; the detector 8 is respectively connected to the optical path of each beam splitter, each beam splitter is connected to the optical path of the corresponding phase modulator, and each phase modulator is connected to the optical path of the optical antenna 7. Since the receiving optical paths corresponding to the waveguide arrays in two directions are used to receive the optical signal at the same time, the light intensity of the received light reaches the strongest and is detected by the detector 8, which can effectively reduce the influence of the depolarization and linear polarization of the received light signal in space, greatly improve the receiving effect of the optical signal, and thus improve the detection capability of the phased array laser radar.

[0113] Embodiment 7

[0114] Embodiment 7 of the present invention provides a phased array laser radar, which includes a transmitting chip of the phased array laser radar and / or a receiving chip of the phased array laser radar.

[0115] The structure and function of the receiving chip of the phased array laser radar provided in this embodiment are the same as those of the receiving chip of the phased array laser radar provided in Example 5. The structure and function of the receiving chip of the phased array laser radar provided in this embodiment are the same as those of the receiving chip of the phased array laser radar provided in Example 6, and are not described one by one here.

[0116] Embodiment 8

[0117] Fig.11 A schematic diagram of a flow chart of a method for transmitting a phased array laser radar according to an eighth embodiment of the present invention is shown in FIG. Fig.11 As shown, the execution subject of the transmission method of the phased array laser radar provided in this embodiment is the transmission chip of the phased array laser radar, and the transmission chip of the phased array laser radar can be coupled in the phased array laser radar. Then, the transmission method of the phased array laser radar provided in this embodiment includes the following steps:

[0118] Step 101: An input coupler couples input light to a transmitting chip.

[0119] In this embodiment, the light source emits an optical signal, the input coupler receives the optical signal emitted by the light source to form input light, and couples the input light to the transmitting chip.

[0120] The wavelength of the light source can be adjusted by a wavelength adjuster at the light source end to adjust the scanning range in the Y direction.

[0121] Step 102: The optical switch controls the input light to work in two groups of emission light paths in a time-sharing manner, so as to scan the corresponding scanning ranges of the two groups of emission light paths.

[0122] The two groups of emission optical paths include a first group of emission optical paths and a second group of emission optical paths. The first group of emission optical paths includes: a first beam splitter, a first phase modulator, and a transverse waveguide array of an optical antenna, a transverse pattern spot converter, and a transverse grating. The second group of emission optical paths includes: a second beam splitter, a second phase modulator, and a longitudinal waveguide array of an optical antenna, a longitudinal pattern spot converter, and a longitudinal grating.

[0123] In this embodiment, the switching cycle of the optical switch can be configured in advance so that the optical switch can complete the switching of the two emission light paths between on and off during the switching cycle, so as to control the input light to work in the two groups of emission light paths in time-sharing manner, so as to realize the scanning of the corresponding scanning ranges of the two groups of emission light paths.

[0124] The scanning range corresponding to each emission light path may be a rectangular scanning range. After the scanning ranges corresponding to the two emission light paths are accumulated, a scanning range similar to a cross can be achieved.

[0125] As an optional implementation, in this embodiment, if Fig.12 As shown, step 102 includes the following steps:

[0126] Step 1021, the optical switch controls the input light to pass through the first beam splitter and the first phase modulator to pass light through the transverse waveguide array, while controlling the second beam splitter and the second phase modulator to block light from passing through the corresponding longitudinal waveguide array.

[0127] Specifically, in this embodiment, the optical switch can control the input light to pass through the first beam splitter and the first phase modulator during the current light-passing time period, and then pass light to the transverse waveguide array. At the same time, the optical switch controls the second beam splitter and the second phase modulator to not pass light to the corresponding longitudinal waveguide array during the current light-passing time period. Then the input light is split by the first beam splitter to couple the input light to the transmitting chip, and the first phase modulator changes the phase of the split input light. The input light with the changed phase is emitted into space through the transverse waveguide array, the transverse pattern spot converter and the transverse grating.

[0128] In step 1022, the first phase modulator adjusts the angle of the emitted light and the wavelength modulator adjusts the wavelength of the light source to achieve two-dimensional scanning in a first range.

[0129] In this embodiment, the first phase modulator changes the phase of the split input light to adjust the angle of the emitted light, thereby adjusting the scanning range in the X direction. The wavelength adjuster adjusts the wavelength of the light source to adjust the scanning range in the Y direction, thereby achieving two-dimensional scanning in the first range.

[0130] Step 1023, the optical switch controls the input light to pass through the second beam splitter and the second phase modulator to pass light through the longitudinal waveguide array, while controlling the first beam splitter and the first phase modulator to block light from passing through the corresponding transverse waveguide array.

[0131] Specifically, in this embodiment, the optical switch can control the input light to pass through the second beam splitter and the second phase modulator in the next light-passing time period, and then pass light to the longitudinal waveguide array. At the same time, the optical switch controls the first beam splitter and the first phase modulator to not pass light to the corresponding transverse waveguide array in the next light-passing time period. Then the input light is split by the second beam splitter to couple the input light to the transmitting chip, and the second phase modulator changes the phase of the split input light. The input light with the changed phase is emitted into space through the longitudinal waveguide array, the longitudinal pattern spot converter and the longitudinal grating.

[0132] In step 1024, the second phase modulator adjusts the angle of the emitted light and the wavelength modulator adjusts the wavelength of the light source to achieve two-dimensional scanning in a second range.

[0133] In this embodiment, the second phase modulator changes the phase of the split input light to adjust the angle of the emitted light, thereby adjusting the scanning range in the X direction. The wavelength adjuster adjusts the wavelength of the light source to adjust the scanning range in the Y direction, thereby achieving two-dimensional scanning in the second range.

[0134] Therefore, in this embodiment, the optical switch controls the input light to pass through the first group of emission light paths in the current light-passing time period, and controls the input light to pass through the second group of emission light paths in the next light-passing time period, thereby realizing the scanning of the corresponding scanning ranges of the two groups of emission light paths. After the scanning ranges corresponding to the two emission light paths are accumulated, the scanning of a cross-like scanning range can be realized.

[0135] The transmitting method of the phased array laser radar provided in this embodiment couples the input light to the transmitting chip through an input coupler, and the optical switch controls the input light to work in two groups of transmitting light paths in time-sharing manner to realize scanning of the scanning ranges corresponding to the two groups of transmitting light paths. Since the two groups of waveguide arrays are orthogonal to each other and the two groups of pattern spot converters are orthogonal to each other, when the optical antenna is used as a transmitting antenna, the transmitting light paths corresponding to the waveguide arrays in two directions are respectively emitted by time-sharing multiplexing, so as to realize scanning of the scanning ranges corresponding to the two groups of transmitting light paths, thereby increasing the scanning range.

[0136] Embodiment 9

[0137] Fig.13 A flow chart of a receiving method of a phased array laser radar provided in Embodiment 9 of the present invention is shown as follows: Fig.13 As shown, the execution subject of the transmission method of the phased array laser radar provided in this embodiment is the receiving chip of the phased array laser radar, and the receiving chip of the phased array laser radar can be coupled in the phased array laser radar. Then, the receiving method of the phased array laser radar provided in this embodiment includes the following steps:

[0138] Step 201: two groups of receiving optical paths in the optical antenna receive receiving optical signals simultaneously.

[0139] Specifically, in this embodiment, the two groups of receiving optical paths include a first group of receiving optical paths and a second group of receiving optical paths. The first group of receiving optical paths includes: a transverse grating, a transverse pattern spot converter, a transverse waveguide array, a first phase modulator and a first beam splitter. The second group of receiving optical paths includes: a longitudinal grating, a longitudinal pattern spot converter, a longitudinal waveguide array, a second phase modulator and a second beam splitter.

[0140] Step 202: Aggregate the received optical signals into a total received optical signal through two groups of receiving optical paths.

[0141] Specifically, in this embodiment, the first group of receiving optical paths sends the received optical signal to the first phase modulator through the transverse grating, the transverse pattern converter, and the transverse waveguide array. The first phase modulator changes the phase of the received optical signal and sends the received optical signal after the phase change to the first beam splitter. The first beam splitter converges the received optical signal after the phase change to form a first received optical total signal.

[0142] At the same time, the second group of receiving optical paths sends the received optical signal to the second phase modulator through the longitudinal grating, the longitudinal pattern converter, and the longitudinal waveguide array. The second phase modulator changes the phase of the received optical signal and sends the received optical signal after the phase change to the second beam splitter. The second beam splitter converges the received optical signal after the phase change to form a second total received optical signal.

[0143] The first beam splitter sends the first received optical signal to the total waveguide connected to the first beam splitter. At the same time, the second beam splitter sends the second received optical signal to the total waveguide connected to the second beam splitter. The total waveguide converges the first received optical signal and the second received optical signal again to form a total received optical signal.

[0144] Step 203: adjust the voltage of each channel of the two phase modulators according to the light intensity of the received total optical signal.

[0145] Specifically, in this embodiment, the intensity of the total received light signal can be obtained, and it is determined whether the intensity of the total received light signal is the maximum intensity. If it is not the maximum intensity, the voltage of each channel of the two phase modulators is adjusted. The specific adjustment method is not limited in this embodiment.

[0146] Step 204: If the light intensity of the received total light signal is the maximum light intensity, the received total light signal is transmitted to the detector.

[0147] In this embodiment, while adjusting the voltage of each channel of the two phase modulators, it is monitored whether the light intensity of the total received light signal is the maximum light intensity. If the light intensity of the total received light signal is the maximum light intensity, it means that the reception effect of the optical signal is the best at this time. The total received light signal is then transmitted to the detector, so that the detector detects the distance of the target object based on the total received light signal.

[0148] The receiving method of the phased array laser radar provided in this embodiment simultaneously receives the received light signal through two groups of receiving light paths in the optical antenna; converges the received light signal into a total received light signal through the two groups of receiving light paths; adjusts the voltage of each channel of the two phase modulators according to the light intensity of the total received light signal; if the light intensity of the total received light signal is the maximum light intensity, the total received light signal is transmitted to the detector, and the light signal is received by the receiving light paths corresponding to the waveguide arrays in two directions, so that the light intensity of the received light signal reaches the strongest and is detected by the detector, which can effectively reduce the influence of depolarization and linear polarization of the received light signal in space, greatly improve the receiving effect of the light signal, and further improve the detection capability of the phased array laser radar.

[0149] Optionally, in this embodiment, after step 204, the following steps are further included:

[0150] Step 205: Set the voltage of each channel corresponding to the maximum light intensity as the phase calibration voltage.

[0151] In this embodiment, since the voltage of each channel corresponding to the maximum light intensity is the voltage of each channel when the receiving effect is optimal, the voltage of each channel corresponding to the maximum light intensity is set as the phase calibration voltage, and the phase calibration voltage is stored.

[0152] Step 206: call the phase calibration voltage to receive the next received optical signal.

[0153] In this embodiment, when receiving the next received light signal, the phase calibration voltage is called. If the voltage of each channel of the phase modulator is a non-phase calibration voltage, the voltage of each channel is adjusted to the phase calibration voltage so that the light intensity of the next received light total signal is also the maximum light intensity, ensuring that the reception effect of subsequent light signals is still optimal, so that the detector can always detect the distance of the target object based on the optimal received light total signal.

[0154] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An optical antenna, characterized in that: include: SOI substrate, two sets of waveguide arrays, two sets of pattern spot converters, silicon slab, two-dimensional grating array and protective layer; The two groups of waveguide arrays, the two groups of pattern spot converters and the silicon flat plate are included in the SOI substrate; a two-dimensional grating array is formed on the silicon flat plate, and the protective layer covers the two groups of waveguide arrays, the two groups of pattern spot converters and the two-dimensional grating array; The two groups of waveguide arrays are respectively connected to the corresponding pattern spot converter optical paths, and the two groups of pattern spot converters are respectively connected to the two-dimensional grating array optical paths; The two groups of waveguide arrays are orthogonal to each other and work in time-sharing mode; the two groups of pattern spot converters are orthogonal to each other; The two groups of waveguide arrays include a transverse waveguide array and a longitudinal waveguide array, and the two-dimensional grating array includes: a transverse grating and a longitudinal grating; The waveguide spacing in the transverse waveguide array is an integer multiple of the longitudinal grating period, and the waveguide spacing in the longitudinal waveguide array is an integer multiple of the transverse grating period.

2. The optical antenna according to claim 1, characterized in that A two-dimensional grating array is etched on the silicon flat plate, and the two-dimensional grating array is a two-dimensional hole structure array; The hole structures in the two-dimensional hole structure array are round holes or square holes.

3. The optical antenna according to claim 1, characterized in that: A spacer layer is arranged on the silicon flat plate, a grating material layer is grown on the spacer layer, and the two-dimensional grating array is etched on the grating material layer, wherein the two-dimensional grating array is a two-dimensional columnar array; The columns of the two-dimensional column array are round columns or square columns.

4. A transmitting chip of a phased array laser radar, characterized in that: include: An input coupler, an optical switch, a first beam splitter, a second beam splitter, a first phase modulator, a second phase modulator, and an optical antenna as claimed in any one of claims 1 to 3; The input coupler is connected to each beam splitter optical path through the optical switch, each beam splitter is connected to a corresponding phase modulator optical path, and each phase modulator is connected to the optical antenna optical path.

5. A receiving chip for a phased array laser radar, characterized in that: include: A detector, a first beam splitter, a second beam splitter, a first phase modulator, a second phase modulator and an optical antenna as claimed in any one of claims 1 to 3; The detector is connected to each beam splitter optical path respectively, each beam splitter is connected to the corresponding phase modulator optical path, and each phase modulator is connected to the optical antenna optical path.

6. A phased array laser radar, characterized in that: Includes the transmitting chip of the phased array laser radar as described in claim 4, and / or includes the receiving chip of the phased array laser radar as described in claim 5.

7. A method for transmitting a phased array laser radar, characterized in that: The method uses the transmitting chip as claimed in claim 4, and the method comprises: The input coupler couples the input light to the transmitting chip; The optical switch controls the input light to work in two groups of emission light paths in a time-sharing manner, so as to realize scanning of the corresponding scanning ranges of the two groups of emission light paths.

8. The method according to claim 7, characterized in that The optical switch controls the input light to work in two groups of emission light paths in a time-sharing manner to achieve scanning of the corresponding scanning ranges of the two groups of emission light paths, including: The optical switch controls the input light to pass through the first beam splitter and the first phase modulator, and then pass the light through the transverse waveguide array, while controlling the second beam splitter and the second phase modulator to block the light from passing through the corresponding longitudinal waveguide array; The first phase modulator adjusts the angle of the emitted light and the wavelength modulator adjusts the wavelength of the light source to achieve two-dimensional scanning in a first range; The optical switch controls the input light to pass through the second beam splitter and the second phase modulator, and then pass light through the longitudinal waveguide array, while controlling the first beam splitter and the first phase modulator to block light from passing through the corresponding transverse waveguide array; The second phase modulator adjusts the angle of the emitted light and the wavelength adjuster adjusts the wavelength of the light source to achieve two-dimensional scanning in the second range.

9. A receiving method of a phased array laser radar, characterized in that: The method adopts the receiving chip as claimed in claim 5, and the method comprises: Two groups of receiving optical paths in the optical antenna receive the receiving optical signal simultaneously; The received optical signals are gathered into a total received optical signal through two groups of receiving optical paths; adjusting the voltage of each channel of the two phase modulators according to the light intensity of the received total light signal; If the light intensity of the received light total signal is the maximum light intensity, the received light total signal is transmitted to the detector.

10. The method according to claim 9, characterized in that If the light intensity of the received total light signal is the maximum light intensity, the method further includes: Setting the voltage of each channel corresponding to the maximum light intensity as a phase calibration voltage; The phase calibration voltage is called to receive the next received optical signal.

Images