A method, apparatus, storage medium, and lidar for obtaining etching depth

Abstract

This application discloses a method, apparatus, storage medium, and lidar for obtaining etching depth. The method includes: obtaining a target etching depth corresponding to a target coupling length ratio at the center wavelength of an optical signal, wherein the target etching depth is any metric value selected from multiple etching depths for etching a waveguide; when the target coupling length ratio is the smallest coupling length ratio in the set of ratios, the target etching depth is determined as the waveguide etching depth for etching the waveguide; the set of ratios includes coupling length ratios corresponding to each etching depth in the set of multiple etching depths, and the coupling length ratio is obtained by considering the optical refractive index corresponding to each etching depth and the sensitivity of the optical refractive index to the shift of the center wavelength. Using this application, the operational stability of the optical coupler can be guaranteed, thereby ensuring the stability of the lidar system.

Description

Technical Field

[0001] This application relates to the field of computer technology, and in particular to a method, apparatus, storage medium and lidar for obtaining etching depth. Background Technology

[0002] Optical couplers play a crucial role in frequency-modulated continuous wave (FMCW) lidar, for example, in setting the splitting ratio of the local oscillator and signal optical paths, and in mixing the local oscillator and signal optical paths. However, in actual use, the performance of optical couplers is easily affected by the lidar system and the environment, which can cause changes in the waveguide refractive index, affecting the working stability of the optical coupler and consequently the stability of the lidar system. Summary of the Invention

[0003] This application provides an etching depth acquisition method, apparatus, storage medium, and lidar, which can ensure the working stability of the optocoupler and thus the stability of the lidar system.

[0004] This application provides a method for obtaining etching depth, including:

[0005] Obtain the target coupling length ratio corresponding to the target etching depth at the center wavelength of the optical signal, wherein the target etching depth is any metric value selected from multiple etching depths for etching the waveguide;

[0006] When the target coupling length ratio is the smallest coupling length ratio in the ratio set, the target etching depth is determined as the waveguide etching depth for etching the waveguide.

[0007] The set of ratios includes the coupling length ratios corresponding to each etching depth in multiple etching depths. The coupling length ratios are obtained by considering the optical refractive index corresponding to each etching depth and the sensitivity of the optical refractive index to the shift of the center wavelength.

[0008] The step of obtaining the target etching depth to the target coupling length ratio at the center wavelength of the optical signal includes:

[0009] Obtain the target optical refractive index corresponding to the target etching depth at the center wavelength of the optical signal;

[0010] Based on the target optical refractive index, obtain the target refractive index difference corresponding to the target etching depth at the center wavelength;

[0011] The target sensitivity value corresponding to the target etching depth is obtained based on the target refractive index difference, and the target sensitivity value is the sensitivity value of the target refractive index difference to the shift of the center wavelength.

[0012] Based on the target refractive index difference and the target sensitivity value, the target etching depth is calculated as the target coupling length ratio at the center wavelength of the optical signal.

[0013] Wherein, obtaining the target refractive index difference corresponding to the target etching depth at the center wavelength based on the target optical refractive index includes:

[0014] Obtain the even-mode and odd-mode refractive indices of the target light refractive index;

[0015] The difference between the even-mode refractive index and the odd-mode refractive index is determined as the target refractive index difference corresponding to the target etching depth at the center wavelength.

[0016] The step of obtaining the target sensitivity value corresponding to the target etching depth based on the target refractive index difference includes:

[0017] Based on the target refractive index difference, a difference curve corresponding to the target etching depth is generated. The difference curve is used to represent the difference curve of the target refractive index difference as the center wavelength shifts.

[0018] Obtain the target slope of the difference curve, and determine the target slope as the target sensitivity value corresponding to the target etching depth.

[0019] This also includes:

[0020] Based on the target refractive index difference and the center wavelength, calculate the target coupling length corresponding to the target etching depth;

[0021] The coupling coefficient corresponding to the target etching depth is determined based on the target coupling length.

[0022] One embodiment of this application provides an etching depth acquisition device, including:

[0023] The length ratio acquisition unit is used to acquire the target coupling length ratio corresponding to the target etching depth at the center wavelength of the optical signal, wherein the target etching depth is any measurement value selected from multiple etching depths for etching the waveguide.

[0024] The etching depth determination unit is used to determine the target etching depth as the waveguide etching depth for etching the waveguide when the target coupling length ratio is the smallest coupling length ratio in the ratio set.

[0025] The set of ratios includes the coupling length ratios corresponding to each etching depth in multiple etching depths. The coupling length ratios are obtained by considering the optical refractive index corresponding to each etching depth and the sensitivity of the optical refractive index to the shift of the center wavelength.

[0026] The length ratio acquisition unit includes:

[0027] The refractive index acquisition subunit is used to acquire the target optical refractive index corresponding to the target etching depth at the center wavelength of the optical signal.

[0028] The difference acquisition subunit is used to acquire the target refractive index difference corresponding to the target etching depth at the center wavelength based on the target optical refractive index;

[0029] The degree value acquisition subunit is used to acquire the target sensitivity value corresponding to the target etching depth based on the target refractive index difference, wherein the target sensitivity value is the sensitivity value of the target refractive index difference as the center wavelength shifts.

[0030] The length ratio acquisition subunit is used to calculate the target coupling length ratio corresponding to the center wavelength of the optical signal at the target etching depth based on the target refractive index difference and the target sensitivity value.

[0031] Specifically, the difference acquisition subunit is used to acquire the even-mode refractive index and the odd-mode refractive index in the target optical refractive index;

[0032] The difference between the even-mode refractive index and the odd-mode refractive index is determined as the target refractive index difference corresponding to the target etching depth at the center wavelength.

[0033] Specifically, the degree value acquisition subunit is used to generate a difference curve corresponding to the target etching depth based on the target refractive index difference. The difference curve is used to represent the difference change curve of the target refractive index difference as the center wavelength shifts.

[0034] Obtain the target slope of the difference curve, and determine the target slope as the target sensitivity value corresponding to the target etching depth.

[0035] This also includes:

[0036] The coupling length acquisition unit is used to calculate the target coupling length corresponding to the target etching depth based on the target refractive index difference and the center wavelength;

[0037] The coupling coefficient determination unit is used to determine the coupling coefficient corresponding to the target etching depth based on the target coupling length.

[0038] One embodiment of this application provides a computer storage medium storing a computer program, the computer program including program instructions, which, when executed by a processor, perform the above-described method steps.

[0039] One embodiment of this application provides a lidar, including a processor, a memory, and an input / output interface;

[0040] The processor is connected to the memory and the input / output interface, respectively. The input / output interface is used for page interaction, the memory is used to store program code, and the processor is used to call the program code to execute the above-described method steps.

[0041] In this embodiment, by obtaining the coupling length ratio of the waveguide of the optical coupler at multiple etching depths and determining the target etching depth corresponding to the smallest coupling length ratio, the waveguide can be etched using the target etching depth. This reduces the correlation between the coupling length of the optical coupler and the wavelength of the optical signal, increases the bandwidth of the optical coupler, ensures the working stability of the optical coupler, and thus ensures the stability of the lidar system. Attached Figure Description

[0042] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0043] Figure 1 This is a cross-sectional view of the waveguide in the optical coupler provided in the embodiments of this application;

[0044] Figure 2 This is a flowchart illustrating a method for obtaining etching depth provided in an embodiment of this application;

[0045] Figure 3 This is a flowchart illustrating a method for obtaining etching depth provided in an embodiment of this application;

[0046] Figure 4 This is a schematic diagram illustrating an example of optical refractive index provided in an embodiment of this application;

[0047] Figure 5 This is a schematic diagram illustrating an example of a refractive index difference provided in an embodiment of this application;

[0048] Figure 6 This is an example diagram illustrating a sensitivity value provided in an embodiment of this application;

[0049] Figure 7 This is a schematic diagram illustrating an example of a coupling length ratio provided in an embodiment of this application;

[0050] Figure 8 This is an example schematic diagram of an optical coupler provided in an embodiment of this application;

[0051] Figure 9 This is a schematic diagram of an etching depth acquisition device provided in an embodiment of this application;

[0052] Figure 10 This is a schematic diagram of an etching depth acquisition device provided in an embodiment of this application;

[0053] Figure 11 This is a schematic diagram of the length ratio acquisition unit provided in an embodiment of this application;

[0054] Figure 12 This is a schematic diagram of the structure of a lidar provided in an embodiment of this application. Detailed Implementation

[0055] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0056] Please see Figure 1 The present application provides a cross-sectional view of the waveguide in the optical coupler. The optical coupler can be a directional coupler composed of two parallel waveguides. Conventional directional couplers are quite sensitive to changes in optical wavelength. Since changes in operating temperature have a certain impact on the performance of the optical coupler, the refractive index of the waveguide for the optical signal changes, the center wavelength of the optical signal shifts, and the stability of the optical coupler cannot be guaranteed. Figure 1 The waveguide shown can be a silicon-based ridge waveguide, wherein the widths of the two waveguides are W and W respectively. a and W b The distance between the two waveguides is G, the waveguide thickness is H, and the etching depth h of the waveguide can be controlled between 0 and H. In this embodiment, the coupling length ratio of the waveguide of the optical coupler at multiple etching depths is obtained, and the target etching depth corresponding to the smallest coupling length ratio is determined. The waveguide can be etched using the target etching depth, which reduces the correlation between the coupling length of the optical coupler and the wavelength of the optical signal, ensures the working stability of the optical coupler, and thus ensures the stability of the lidar system.

[0057] based on Figure 1 The waveguide structure shown below will be combined with... Figures 2-8 The illustrated embodiment provides a detailed description of the etching depth acquisition method provided in this application.

[0058] Please see Figure 2 This is a flowchart illustrating a method for obtaining etching depth according to an embodiment of this application. Figure 2 As shown, the method described in this application embodiment may include the following steps S101-S102.

[0059] S101, obtain the target coupling length ratio corresponding to the target etching depth at the center wavelength of the optical signal;

[0060] Specifically, the etching depth acquisition device acquires the target coupling length ratio corresponding to the target etching depth at the center wavelength of the optical signal. The target etching depth is any metric value selected from multiple etching depths for etching the waveguide. These multiple etching depths can be divided according to actual needs. The center wavelength is the wavelength corresponding to the center position of the optical signal at the full width at half maximum (FWHM). FWHM refers to the wavelength difference corresponding to the intensity drop to half the peak value on both sides of the spectral peak. Therefore, the wavelength of the optical signal covers a certain wavelength range. The etching depth acquisition device acquires the center wavelength of the optical signal within the wavelength range and acquires the target coupling length ratio corresponding to the target etching depth at the center wavelength. The target coupling length ratio can be specifically determined by the target optical refractive index corresponding to the target etching depth and the sensitivity value of the optical refractive index to the shift of the center wavelength. The target optical refractive index can be the effective refractive index of the optical coupler for the optical signal at the center wavelength.

[0061] S102, when the target coupling length ratio is the smallest coupling length ratio in the ratio set, the target etching depth is determined as the waveguide etching depth for etching the waveguide;

[0062] Specifically, the etching depth acquisition device can generate a set of ratios based on the coupling length ratios corresponding to each etching depth among multiple etching depths, and obtain the smallest coupling length ratio from the set. The etching depth corresponding to this smallest coupling length ratio can then be used as the waveguide etching depth for etching the waveguide. For example, when the target coupling length ratio is the smallest in the set, the etching depth acquisition device can determine the target etching depth as the waveguide etching depth for etching the waveguide. By obtaining the waveguide etching depth, the coupling length ratio of the optical coupler can be minimized, reducing the impact of center wavelength shift changes on the optical refractive index and reducing the correlation between the coupling length of the optical coupler and the wavelength of the optical signal.

[0063] In this embodiment, by obtaining the coupling length ratio of the waveguide of the optical coupler at multiple etching depths and determining the target etching depth corresponding to the smallest coupling length ratio, the waveguide can be etched using the target etching depth. This reduces the correlation between the coupling length of the optical coupler and the wavelength of the optical signal, increases the bandwidth of the optical coupler, ensures the working stability of the optical coupler, and thus ensures the stability of the lidar system.

[0064] Please see Figure 3 This is a flowchart illustrating a method for obtaining etching depth according to an embodiment of this application. Figure 3 As shown, the method described in this application embodiment may include the following steps S201-S207.

[0065] S201, Obtain the target optical refractive index corresponding to the target etching depth at the center wavelength of the optical signal;

[0066] Specifically, the etching depth acquisition device can acquire the target optical refractive index corresponding to the target etching depth at the center wavelength of the optical signal. The target optical refractive index can be the effective refractive index of the optical coupler for the optical signal at the center wavelength. Optionally, the target optical refractive index can further include even-mode refractive index and odd-mode refractive index. Even-mode means that the optical signal is transmitted by two waveguides of the optical coupler with the same phase, and odd-mode means that the optical signal is transmitted by two waveguides of the optical coupler with a phase difference of 180 degrees. The etching depth acquisition device can acquire the even-mode refractive index and odd-mode refractive index corresponding to the target etching depth at the center wavelength of the optical signal, respectively.

[0067] Optionally, the operating center wavelength of the lidar system is 1550nm, and the waveguide width W a =W b Taking an example with a waveguide thickness of 500nm, a spacing of 200nm between the two waveguides, and a waveguide thickness of 220nm. Please refer to [other sources]. Figure 4 The diagram below provides an example of optical refractive index for embodiments of this application. Figure 4 As shown, the etching depth acquisition device can acquire the even-mode and odd-mode refractive indices of each etching depth at different wavelengths within multiple etching depths, and form a pattern as shown in the figure. Figure 4 The graph shown represents the refractive index of light. Assuming the even-mode refractive index is n1 and the odd-mode refractive index is n2, the variation curve of the even-mode refractive index at different wavelengths for each etching depth can be represented as n1(λ), ​​and the variation curve of the odd-mode refractive index can be represented as n2(λ). Figure 4 The figures show n1(λ) and n2(λ) for etching depths h of 40 nm, 100 nm, 160 nm, and 220 nm. Of course, Figure 4The n1(λ) and n2(λ) corresponding to each h shown are only examples. The range of h can be (0, H], and h can be set according to actual needs.

[0068] S202, based on the target optical refractive index, obtain the target refractive index difference corresponding to the target etching depth at the center wavelength;

[0069] Specifically, the etching depth acquisition device can obtain the target refractive index difference corresponding to the target etching depth at the center wavelength based on the target optical refractive index. Optionally, the etching depth acquisition device can obtain the even-mode refractive index and the odd-mode refractive index in the target optical refractive index, and the etching depth acquisition device determines the difference between the even-mode refractive index and the odd-mode refractive index as the target refractive index difference corresponding to the target etching depth at the center wavelength.

[0070] Please see also Figure 5 This provides an example diagram illustrating the refractive index difference in embodiments of this application. For example... Figure 5 As shown, the etching depth acquisition device can acquire the refractive index difference of each etching depth at different wavelengths within multiple etching depths, and form a data set as shown in the figure. Figure 5 The difference curve shown above, based on the example above, can be represented as the curve of the change in refractive index difference at different wavelengths for each etching depth, as n1(λ)-n2(λ). Figure 5 The diagram shows n1(λ)-n2(λ) for etching depths h of 20nm, 40nm, 60nm, 80nm, 100nm, 120nm, 140nm, 160nm, 180nm, 200nm, and 220nm. Of course, Figure 5 The n1(λ)-n2(λ) values ​​shown for each h are just examples. The range of h values ​​can be (0, H], and h can be set according to actual needs.

[0071] S203, based on the target refractive index difference, obtain the target sensitivity value corresponding to the target etching depth;

[0072] Specifically, the etching depth acquisition device obtains a target sensitivity value corresponding to the target etching depth based on the target refractive index difference. The target sensitivity value can further be the sensitivity value of the target refractive index difference as a function of the shift of the center wavelength. Optionally, the etching depth acquisition device can generate a difference curve corresponding to the target etching depth based on the target refractive index difference. The difference curve represents the difference curve of the target refractive index difference as a function of the shift of the center wavelength. The etching depth acquisition device can obtain the target slope of the difference curve and determine the target slope as the target sensitivity value corresponding to the target etching depth.

[0073] Please see also Figure 6 The diagram illustrates an example of sensitivity values ​​in the embodiments of this application. Figure 6 As shown, the etching depth acquisition device can acquire the sensitivity value corresponding to each etching depth among multiple etching depths, and form a value as shown in the figure. Figure 6 The coordinate point plot of the sensitivity values ​​shown above, based on the example above, shows that the sensitivity value corresponding to each etching depth can be expressed as Δ(n1(λ)-n2(λ)). Figure 6 The diagram shows Δ(n1(λ)-n2(λ)) for etching depths h of 20nm, 40nm, 60nm, 80nm, 100nm, 120nm, 140nm, 160nm, 180nm, 200nm, and 220nm. Of course, Figure 6 The △(n1(λ)-n2(λ)) corresponding to each h shown are only examples. The range of h can be (0, H], and h can be set according to actual needs.

[0074] S204, Based on the target refractive index difference and the target sensitivity value, calculate the target coupling length ratio corresponding to the target etching depth at the center wavelength of the optical signal;

[0075] Specifically, the etching depth acquisition device can calculate the target coupling length ratio corresponding to the target etching depth at the center wavelength of the optical signal based on the target refractive index difference and the target sensitivity value. Optionally, the etching depth acquisition device can use the ratio of the target sensitivity value and the target refractive index difference as the target coupling length ratio corresponding to the target etching depth at the center wavelength of the optical signal.

[0076] Please see also Figure 7 This provides an example diagram illustrating the coupling length ratio in an embodiment of this application. For example... Figure 7 As shown, the etching depth acquisition device can acquire the coupling length ratio corresponding to each etching depth among multiple etching depths, and form a value as shown in the figure. Figure 7 The coordinate point diagram of the coupling length ratio shown above, based on the example above, takes a center wavelength of 1550nm as an example in this application embodiment. The coupling length ratio corresponding to each etching depth can be expressed as ΔLπ(λ) / Lπ(λ), where Lπ(λ) is the coupling length required for the optical signal to couple from one waveguide to another. ΔLπ(λ) / Lπ(λ) can specifically be expressed as the ratio of the change in coupling length caused by the wavelength change due to the center wavelength shift. Lπ(λ) can specifically be expressed as:

[0077]

[0078] Then △Lπ(λ) / Lπ(λ) can be expressed as:

[0079]

[0080] In this equation, the first term can be ignored, and the equation can be simplified to:

[0081]

[0082] Therefore, the etching depth acquisition device can be combined with Figure 5 The obtained n1(λ)-n2(λ) and Figure 6 The obtained Δ(n1(λ)-n2(λ)) is used to calculate ΔLπ(λ) / Lπ(λ), where the wavelength is preferably 1550nm. The smaller the ratio of Δ(n1(λ)-n2(λ)) to n1(λ)-n2(λ), the closer ΔLπ(λ) / Lπ(λ) is to 0, indicating that the influence of the center wavelength shift is smaller, thus reducing the correlation between the coupling length of the optical coupler and the wavelength of the optical signal.

[0083] Figure 7 The diagram shows Δ(n1(λ)-n2(λ)) for etching depths h of 20nm, 40nm, 60nm, 80nm, 100nm, 120nm, 140nm, 160nm, 180nm, 200nm, and 220nm. Of course, Figure 7 The △(n1(λ)-n2(λ)) corresponding to each h shown are only examples. The range of h can be (0, H], and h can be set according to actual needs.

[0084] S205, when the target coupling length ratio is the smallest coupling length ratio in the ratio set, the target etching depth is determined as the waveguide etching depth for etching the waveguide;

[0085] Specifically, the etching depth acquisition device can generate a set of ratios based on the coupling length ratios corresponding to each etching depth among multiple etching depths, and obtain the smallest coupling length ratio from the set. The etching depth corresponding to this smallest coupling length ratio can then be used as the waveguide etching depth for etching the waveguide. For example, when the target coupling length ratio is the smallest in the set, the etching depth acquisition device can determine the target etching depth as the waveguide etching depth for etching the waveguide. By obtaining the waveguide etching depth, the coupling length ratio of the optical coupler can be minimized, reducing the impact of center wavelength shift changes on the optical refractive index and reducing the correlation between the coupling length of the optical coupler and the wavelength of the optical signal.

[0086] Please see again Figure 7 ,exist Figure 7From the set of ratios formed by the coupling length ratios corresponding to each etching depth, the etching depth acquisition device can obtain the coupling length ratio with the smallest value. Figure 7 It can be seen that there is a minimum coupling length ratio when h = 40nm, so h = 40nm can be determined as the waveguide etching depth for waveguide etching.

[0087] S206, Based on the target refractive index difference and the center wavelength, calculate the target coupling length corresponding to the target etching depth;

[0088] Specifically, after determining the target etching depth as the waveguide etching depth, the etching depth acquisition device can further calculate the target coupling length corresponding to the target etching depth based on the target refractive index difference and the center wavelength. According to the above example, the target coupling length can be calculated using the following formula:

[0089]

[0090] S207, Determine the coupling coefficient corresponding to the target etching depth based on the target coupling length;

[0091] Specifically, the etching depth acquisition device can determine the coupling coefficient corresponding to the target etching depth based on the target coupling length. The coupling coefficient determines the device performance of the optical coupler and can be expressed as C(λ). Based on the above example, the coupling coefficient can be calculated using the following formula:

[0092]

[0093] In this embodiment, the optimal coupling coefficient of the optical coupler can be obtained by changing the structure of the etching depth, thus ensuring the working performance of the optical coupler.

[0094] Optionally, to further reduce the correlation between the coupling length of the optical coupler and the wavelength of the optical signal, the structure of the optical coupler can be improved. Please refer to [link to relevant documentation]. Figure 8 This application provides an example schematic diagram of an optical coupler. In this optical coupler, a grating structure can be further incorporated to determine the center wavelength of the optical signal, thereby controlling the even-mode and odd-mode refractive indices corresponding to the center wavelength of the optical signal. Of course, Figure 8 The diagram shows only one possible combination method. The grating structure can be added at any location of the optical coupler, and the grating structure is preferably a subwavelength grating.

[0095] In this embodiment, by obtaining the coupling length ratio of the waveguide of the optical coupler at multiple etching depths and determining the target etching depth corresponding to the smallest coupling length ratio, the waveguide can be etched using the target etching depth. This reduces the correlation between the coupling length of the optical coupler and the wavelength of the optical signal, increases the bandwidth of the optical coupler, ensures the working stability of the optical coupler, and thus ensures the stability of the lidar system. By changing the structure of the etching depth, the optimal coupling coefficient of the optical coupler can be obtained, ensuring the working performance of the optical coupler.

[0096] based on Figure 1 The waveguide structure shown below will be discussed in conjunction with the attached diagram. Figure 9 -Appendix Figure 11 This application provides a detailed description of the etching depth acquisition device provided in its embodiments. It should be noted that the appendix... Figure 9 -Appendix Figure 11 The etching depth acquisition device in the present application is used to perform the etching depth acquisition device. Figures 2-8 The methods shown in the embodiments are for illustrative purposes only, illustrating the parts relevant to the embodiments of this application. For specific technical details not disclosed, please refer to this application. Figures 2-8 The example shown.

[0097] Please see Figure 9 This is a schematic diagram of an etching depth acquisition device provided in an embodiment of this application. Figure 9 As shown, the etching depth acquisition device 1 in this embodiment may include: a length ratio acquisition unit 11 and an etching depth determination unit 12.

[0098] The length ratio acquisition unit 11 is used to acquire the target coupling length ratio corresponding to the target etching depth at the center wavelength of the optical signal, wherein the target etching depth is any measurement value selected from multiple etching depths for etching the waveguide.

[0099] The etching depth determination unit 12 is used to determine the target etching depth as the waveguide etching depth when the target coupling length ratio is the smallest coupling length ratio in the ratio set;

[0100] The set of ratios includes the coupling length ratios corresponding to each etching depth in multiple etching depths. The coupling length ratios are obtained by considering the optical refractive index corresponding to each etching depth and the sensitivity of the optical refractive index to the shift of the center wavelength.

[0101] In this embodiment, by obtaining the coupling length ratio of the waveguide of the optical coupler at multiple etching depths and determining the target etching depth corresponding to the smallest coupling length ratio, the waveguide can be etched using the target etching depth. This reduces the correlation between the coupling length of the optical coupler and the wavelength of the optical signal, increases the bandwidth of the optical coupler, ensures the working stability of the optical coupler, and thus ensures the stability of the lidar system.

[0102] Please see Figure 10 This is a schematic diagram of an etching depth acquisition device provided in an embodiment of this application. Figure 10 As shown, the etching depth acquisition device 1 in this application embodiment may include: a length ratio acquisition unit 11, an etching depth determination unit 12, a coupling length acquisition unit 13, and a coupling coefficient determination unit 14.

[0103] The length ratio acquisition unit 11 is used to acquire the target coupling length ratio corresponding to the target etching depth at the center wavelength of the optical signal, wherein the target etching depth is any measurement value selected from multiple etching depths for etching the waveguide.

[0104] For details, please refer to the following: Figure 11 The diagram below provides a structural schematic of the length ratio acquisition unit for embodiments of this application. Figure 11 As shown, the length ratio acquisition unit 11 may include:

[0105] The refractive index acquisition subunit 111 is used to acquire the target optical refractive index corresponding to the target etching depth at the center wavelength of the optical signal;

[0106] The difference acquisition subunit 112 is used to acquire the target refractive index difference corresponding to the target etching depth at the center wavelength based on the target optical refractive index.

[0107] Specifically, the difference acquisition subunit 112 is used to acquire the even-mode refractive index and the odd-mode refractive index in the target optical refractive index, and to determine the difference between the even-mode refractive index and the odd-mode refractive index as the target refractive index difference corresponding to the target etching depth at the center wavelength.

[0108] The degree value acquisition subunit 113 is used to acquire the target sensitivity value corresponding to the target etching depth based on the target refractive index difference, wherein the target sensitivity value is the sensitivity value of the target refractive index difference as the center wavelength shifts.

[0109] Specifically, the degree value acquisition subunit 113 is used to generate a difference curve corresponding to the target etching depth based on the target refractive index difference. The difference curve is used to represent the difference change curve of the target refractive index difference as the center wavelength shifts. The target slope of the difference curve is obtained, and the target slope is determined as the target sensitivity value corresponding to the target etching depth.

[0110] The length ratio acquisition subunit 114 is used to calculate the target coupling length ratio corresponding to the center wavelength of the optical signal based on the target refractive index difference and the target sensitivity value.

[0111] The etching depth determination unit 12 is used to determine the target etching depth as the waveguide etching depth when the target coupling length ratio is the smallest coupling length ratio in the ratio set;

[0112] The set of ratios includes the coupling length ratios corresponding to each etching depth in multiple etching depths. The coupling length ratios are obtained by considering the optical refractive index corresponding to each etching depth and the sensitivity of the optical refractive index to the shift of the center wavelength.

[0113] The coupling length acquisition unit 13 is used to calculate the target coupling length corresponding to the target etching depth based on the target refractive index difference and the center wavelength;

[0114] The coupling coefficient determination unit 14 is used to determine the coupling coefficient corresponding to the target etching depth based on the target coupling length.

[0115] In this embodiment, by obtaining the coupling length ratio of the waveguide of the optical coupler at multiple etching depths and determining the target etching depth corresponding to the smallest coupling length ratio, the waveguide can be etched using the target etching depth. This reduces the correlation between the coupling length of the optical coupler and the wavelength of the optical signal, increases the bandwidth of the optical coupler, ensures the working stability of the optical coupler, and thus ensures the stability of the lidar system. By changing the structure of the etching depth, the optimal coupling coefficient of the optical coupler can be obtained, ensuring the working performance of the optical coupler.

[0116] This application also provides a computer storage medium that can store multiple program instructions, which are adapted to be loaded and executed by a processor as described above. Figures 2-7 The method steps of the illustrated embodiment can be found in the following documentation for detailed execution. Figures 2-7 The specific details of the illustrated embodiments will not be elaborated here.

[0117] Please see Figure 12The diagram below provides a structural schematic of a lidar according to an embodiment of this application. Figure 12 As shown, the lidar 1000 may include: at least one processor 1001, such as a CPU; at least one network interface 1004; an input / output interface 1003; a memory 1005; and at least one communication bus 1002. The communication bus 1002 is used to enable communication between these components. The network interface 1004 may optionally include a standard wired interface or a wireless interface (such as a Wi-Fi interface). The memory 1005 may be high-speed RAM or non-volatile memory, such as at least one disk storage device. Optionally, the memory 1005 may also be at least one storage device located remotely from the aforementioned processor 1001. Figure 12 As shown, the memory 1005, which serves as a computer storage medium, may include an operating system, a network communication module, an input / output interface module, and a depth acquisition application.

[0118] exist Figure 12 In the lidar 1000 shown, the input / output interface 1003 is mainly used to provide an input interface for users and access devices to acquire data input by users and access devices.

[0119] In one embodiment, processor 1001 can be used to invoke a depth acquisition application stored in memory 1005 and specifically perform the following operations:

[0120] Obtain the target coupling length ratio corresponding to the target etching depth at the center wavelength of the optical signal, wherein the target etching depth is any metric value selected from multiple etching depths for etching the waveguide;

[0121] When the target coupling length ratio is the smallest coupling length ratio in the ratio set, the target etching depth is determined as the waveguide etching depth for etching the waveguide.

[0122] The set of ratios includes the coupling length ratios corresponding to each etching depth in multiple etching depths. The coupling length ratios are obtained by considering the optical refractive index corresponding to each etching depth and the sensitivity of the optical refractive index to the shift of the center wavelength.

[0123] Optionally, when the processor 1001 executes the operation of obtaining the target coupling length ratio corresponding to the target etching depth at the center wavelength of the optical signal, it specifically performs the following operations:

[0124] Obtain the target optical refractive index corresponding to the target etching depth at the center wavelength of the optical signal;

[0125] Based on the target optical refractive index, obtain the target refractive index difference corresponding to the target etching depth at the center wavelength;

[0126] The target sensitivity value corresponding to the target etching depth is obtained based on the target refractive index difference, and the target sensitivity value is the sensitivity value of the target refractive index difference to the shift of the center wavelength.

[0127] Based on the target refractive index difference and the target sensitivity value, the target etching depth is calculated as the target coupling length ratio at the center wavelength of the optical signal.

[0128] Optionally, when the processor 1001 executes the operation of obtaining the target refractive index difference corresponding to the target etching depth at the center wavelength based on the target optical refractive index, it specifically performs the following operations:

[0129] Obtain the even-mode and odd-mode refractive indices of the target light refractive index;

[0130] The difference between the even-mode refractive index and the odd-mode refractive index is determined as the target refractive index difference corresponding to the target etching depth at the center wavelength.

[0131] Optionally, when the processor 1001 executes the operation of obtaining the target sensitivity value corresponding to the target etching depth based on the target refractive index difference, it specifically performs the following operations:

[0132] Based on the target refractive index difference, a difference curve corresponding to the target etching depth is generated. The difference curve is used to represent the difference curve of the target refractive index difference as the center wavelength shifts.

[0133] Obtain the target slope of the difference curve, and determine the target slope as the target sensitivity value corresponding to the target etching depth.

[0134] Optionally, the processor 1001 also performs the following operations:

[0135] Based on the target refractive index difference and the center wavelength, calculate the target coupling length corresponding to the target etching depth;

[0136] The coupling coefficient corresponding to the target etching depth is determined based on the target coupling length.

[0137] In this embodiment, by obtaining the coupling length ratio of the waveguide of the optical coupler at multiple etching depths and determining the target etching depth corresponding to the smallest coupling length ratio, the waveguide can be etched using the target etching depth. This reduces the correlation between the coupling length of the optical coupler and the wavelength of the optical signal, increases the bandwidth of the optical coupler, ensures the working stability of the optical coupler, and thus ensures the stability of the lidar system. By changing the structure of the etching depth, the optimal coupling coefficient of the optical coupler can be obtained, ensuring the working performance of the optical coupler.

[0138] Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. The storage medium can be a magnetic disk, optical disk, read-only memory (ROM), or random access memory (RAM), etc.

[0139] The above-disclosed embodiments are merely preferred embodiments of this application and should not be construed as limiting the scope of this application. Therefore, any equivalent variations made in accordance with the claims of this application shall still fall within the scope of this application.

Claims

1. A method of etch depth acquisition, comprising: The method comprises the following steps: obtaining a target coupling length ratio corresponding to a target etching depth at a center wavelength of an optical signal, the target etching depth being a selected etching depth of a waveguide; when the target coupling length ratio is the minimum coupling length ratio in a ratio set, determining the target etching depth as the waveguide etching depth of the waveguide etching process; the ratio set comprises a coupling length ratio corresponding to each etching depth in a plurality of etching depths, and the coupling length ratio is obtained by an optical refractive index corresponding to each etching depth and a sensitive degree value of the change of the optical refractive index with the offset of the center wavelength.

2. The method of claim 1, wherein, The method comprises the following steps: obtaining a target optical refractive index corresponding to a target etching depth at a center wavelength of an optical signal; obtaining a target refractive index difference corresponding to the target etching depth at the center wavelength based on the target optical refractive index; obtaining a target sensitive degree value corresponding to the target etching depth based on the target refractive index difference, the target sensitive degree value being a sensitive degree value of the target refractive index difference with the offset of the center wavelength; calculating a target coupling length ratio corresponding to the target etching depth at the center wavelength of the optical signal based on the target refractive index difference and the target sensitive degree value.

3. The method of claim 2, wherein, The method comprises the following steps: obtaining a target optical refractive index corresponding to a target etching depth at a center wavelength of an optical signal; obtaining a target refractive index difference corresponding to the target etching depth at the center wavelength based on the target optical refractive index; 4. The method of claim 2, wherein, obtaining a target sensitive degree value corresponding to the target etching depth based on the target refractive index difference, the target sensitive degree value being a sensitive degree value of the target refractive index difference with the offset of the center wavelength; calculating a target coupling length ratio corresponding to the target etching depth at the center wavelength of the optical signal based on the target refractive index difference and the target sensitive degree value. The method comprises the following steps:

5. The method of claim 2, wherein, obtaining an even mode refractive index and an odd mode refractive index in the target optical refractive index; determining a difference value of the even mode refractive index and the odd mode refractive index as a target refractive index difference corresponding to the target etching depth at the center wavelength. The method comprises the following steps:

6. An etch depth acquisition apparatus, comprising: generating a difference curve corresponding to the target etching depth based on the target refractive index difference, the difference curve being used to represent a difference change curve of the target refractive index difference with the offset of the center wavelength; obtaining a target slope of the difference curve, and determining the target slope as the target sensitive degree value corresponding to the target etching depth. The method further comprises the following steps: calculating a target coupling length corresponding to the target etching depth based on the target refractive index difference and the center wavelength; determining a coupling coefficient corresponding to the target etching depth based on the target coupling length. The method comprises the following steps: a length ratio obtaining unit is configured to obtain a target coupling length ratio corresponding to a target etching depth at a center wavelength of an optical signal, the target etching depth being a selected etching depth of a waveguide; an etching depth determining unit is configured to determine the target etching depth as the waveguide etching depth of the waveguide etching process when the target coupling length ratio is the minimum coupling length ratio in a ratio set; the ratio set comprises a coupling length ratio corresponding to each etching depth in a plurality of etching depths, and the coupling length ratio is obtained by an optical refractive index corresponding to each etching depth and a sensitive degree value of the change of the optical refractive index with the offset of the center wavelength.

7. The apparatus of claim 6, wherein, The length ratio obtaining unit comprises: An index of refraction obtaining subunit configured to obtain a target optical index of refraction corresponding to the target etching depth at a center wavelength of the optical signal; A difference value obtaining subunit configured to obtain a target index of refraction difference corresponding to the target etching depth at the center wavelength based on the target optical index of refraction; A degree value obtaining subunit configured to obtain a target sensitivity degree value corresponding to the target etching depth based on the target index of refraction difference, the target sensitivity degree value being a sensitivity degree value of the target index of refraction difference varying with an offset of the center wavelength; A length ratio obtaining subunit configured to calculate a target coupling length ratio corresponding to the target etching depth at the center wavelength of the optical signal based on the target index of refraction difference and the target sensitivity degree value.

8. The apparatus of claim 7, wherein, The difference value obtaining subunit is specifically configured to obtain an even mode index of refraction and an odd mode index of refraction in the target optical index of refraction; A difference value between the even mode index of refraction and the odd mode index of refraction is determined as the target index of refraction difference corresponding to the target etching depth at the center wavelength.

9. A lidar, comprising: A processor, a memory, and an input / output interface are included; The processor is connected with the memory and the input / output interface, respectively, wherein the input / output interface is configured to perform page interaction, the memory is configured to store program code, and the processor is configured to call the program code to execute the method according to any one of claims 1-5.

10. A computer storage medium, characterized in that, The computer storage medium stores a computer program, and the computer program comprises program instructions, which, when executed by a processor, execute the method according to any one of claims 1-5.

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