Waveguide lens type light beam scanning and control method

Abstract

The invention discloses a waveguide lens type light beam scanning and control method. The method is realized based on a waveguide lens type light beam scanning and control device. The device comprises an input waveguide, a multi-mode waveguide and a plurality of strip-shaped electrodes located around the multi-mode waveguide. The input waveguide and the multi-mode waveguide are sequentially arranged in the direction x, the input waveguide is connected with the input end of the multi-mode waveguide, and the output end of the multi-mode waveguide is in contact with air; when the multi-mode waveguide is a two-dimensional multi-mode waveguide, the electrodes are arranged around the multi-mode waveguide, are in cascade arrangement along a direction x, and are arranged at intervals along a direction y vertical to the x; when the multi-mode waveguide is a three-dimensional multi-mode waveguide, the electrodes are also arranged at intervals along a direction z vertical to x and y; when the position of the input light source is not changed, the position of the electrode relative to the light source and the heating power of the electrode are changed, so that the output position and angle of the light beam and the size of the light spot are continuously adjusted. According to the invention, the output position and angle of the light beam and the size of the output light spot can be flexibly and continuously regulated.

Description

Technical Field

[0001] The invention relates to the field of light beam scanning and control, and in particular to a waveguide lens type light beam scanning and control method. Background Art

[0002] Optical beam steerer (OBS) is widely used in optical detection, high-precision sensing, free-space optical communication and other fields. In these applications, in order to achieve high-precision and high-performance beam control systems, strict requirements are placed on parameters such as the position, angle and spot size of the beam.

[0003] In the related art, commonly used beam control schemes mainly include mechanical and MicroElectro Mechanical Systems (MEMS). These methods are usually used to adjust the output angle and position of the light beam. However, its main disadvantage is that it is bulky, requires complex mechanical rotation and precise calibration, and the device has a limited service life. Another common solution is Liquid Crystal On Silicon (LCoS) technology, the working principle of which is to adjust the phase of the light field by adjusting the liquid crystal layer, thereby adjusting the wavefront equiphase surface to achieve control of the light beam. However, the main disadvantage of LCoS is that the adjustment speed is slow and the size of a single control unit is large, which limits its application flexibility. In addition, the control accuracy of the above-mentioned devices is often limited by the number of unit devices, and continuous adjustment is impossible in principle.

[0004] In contrast, beam control devices based on photonic integrated circuits (PICs) have the advantages of small overall size, low power consumption, and high integration. Among them, the most common PICs-type beam control device is the optical phased array (OPA). The concept of OPA comes from the microwave phased array, which adjusts the phase on multiple waveguide arrays through optical phase shifters, thereby adjusting the wavefront equiphase surface at the output end, and uses Fraunhofer diffraction to achieve the emission of beams at different angles to achieve the scanning function. However, the control accuracy and angle range of OPA are limited by the phase error of the optical phase shifter and the number of output waveguides. In addition, OPA has side lobe beams, which affect the overall imaging quality and require complex electronic drive feedback adjustment. With the increase in the number of control waveguide arrays, the complexity and cost of the device also increase accordingly. Therefore, the field of beam control urgently needs a continuous beam scanning and control device with a relatively simple structure, high control freedom, and a wide angle coverage range to meet the needs of practical applications. Summary of the invention

[0005] In view of the shortcomings of the prior art, the present invention discloses a waveguide lens type light beam scanning and control method, which realizes continuous adjustment of the output position, output angle and output spot shape and size of the light beam through a plurality of strip electrodes. The method has flexible light beam control capability and can meet the requirements for light beam regulation in different scenarios.

[0006] The purpose of the present invention is achieved through the following technical solutions:

[0007] A waveguide lens type beam scanning and control method, the method is implemented based on a waveguide lens type beam scanning and control device;

[0008] The waveguide lens type beam scanning and control device comprises: an input waveguide, a multimode waveguide and a plurality of strip electrodes located around the multimode waveguide;

[0009] The input waveguide and the multimode waveguide are arranged in sequence along a first direction x, and the input waveguide is connected to an input end of the multimode waveguide, and an output end of the multimode waveguide is in contact with air;

[0010] When the multimode waveguide is a two-dimensional multimode waveguide, a plurality of strip electrodes are arranged around the multimode waveguide and are arranged in cascade along a first direction x, and are arranged at intervals along a second direction y perpendicular to the first direction x;

[0011] When the multimode waveguide is a three-dimensional multimode waveguide, the plurality of strip electrodes are also arranged at intervals along a third direction z perpendicular to the first direction x and the second direction y;

[0012] The input waveguide and the multimode waveguide are made of optical waveguide materials with thermo-optical effect;

[0013] When the position of the input light source remains unchanged, the output position, output angle and output spot shape of the light beam can be continuously adjusted by changing the position of the strip electrode relative to the input light source and the heating power of the strip electrode.

[0014] Furthermore, in the xoy plane, strip electrodes are selected to be arranged symmetrically in the y direction with respect to the input light source, and two of them form strip electrode pairs, so as to ensure that the heating power of the strip electrode pairs is always equal. By adjusting the size of the heating power, the focal length of the waveguide lens is changed, thereby changing the size of the output light spot at a fixed output position;

[0015] and / or,

[0016] In the xoz plane, strip electrodes are selected that are arranged symmetrically in the z direction with respect to the input light source, and pairs of strip electrodes are formed to ensure that the heating power of the strip electrodes is always equal. By adjusting the heating power, the focal length of the waveguide lens is changed, thereby changing the size of the output light spot at a fixed output position.

[0017] Furthermore, in the xoy plane, strip electrodes are selected to be arranged symmetrically in the y direction with respect to the input light source, and two of them form strip electrode pairs, and the heating powers of the strip electrode pairs are adjusted to be unequal, so that they have a certain angle deflection relative to the waveguide lens when the heating powers are equal, thereby changing the deflection angle of the output light spot in the y direction at a fixed output position;

[0018] and / or,

[0019] In the xoz plane, strip electrodes are selected to be arranged symmetrically in the z direction with respect to the input light source, and pairs of strip electrodes are formed. The heating powers of the strip electrode pairs are adjusted to be unequal, so that they have a certain angle deflection relative to the waveguide lens when the heating powers are equal, thereby changing the deflection angle of the output light spot in the z direction at a fixed output position.

[0020] Furthermore, in the xoy plane, the x-direction position is fixed, and strip electrodes located on both sides of the input light source and asymmetrically arranged with respect to the input light source are selected in the y direction, and two of them form strip electrode pairs, and the heating power of the strip electrode pairs is ensured to be always equal. At this time, the position of the output light spot is offset in the y direction to a certain extent relative to the case where the strip electrode pairs are symmetrically distributed with respect to the input light source, thereby achieving the change of the position of the output light spot in the y direction;

[0021] and / or,

[0022] In the xoz plane, the x-direction position is fixed, and in the z-direction, strip electrodes located on both sides of the input light source and asymmetrically arranged with respect to the input light source are selected to form strip electrode pairs in pairs, and it is ensured that the heating power of the strip electrode pairs is always equal. At this time, the position of the output light spot has a certain offset in the z-direction relative to the case where the strip electrode pairs are symmetrically distributed with respect to the input light source, thereby achieving the change of the position of the output light spot in the z-direction.

[0023] Furthermore, in the xoy plane, the output position, output angle, and output spot shape of the output beam can be adjusted continuously in any combination by combining the following three methods as needed:

[0024] Method 1: Select strip electrodes that are symmetrically arranged in the y direction with respect to the input light source, and form strip electrode pairs in pairs to ensure that the heating power of the strip electrode pairs is always equal. By adjusting the size of the heating power, the focal length of the waveguide lens is changed, thereby changing the size of the output light spot.

[0025] Method 2: Select strip electrodes that are symmetrically arranged in the y direction with respect to the input light source, form strip electrode pairs in pairs, and adjust the heating power of the strip electrode pairs to make them unequal, so that they have a certain angle deflection relative to the waveguide lens when the heating power is equal, thereby changing the deflection angle of the output light spot in the y direction;

[0026] Method 3: fix the position in the x direction, select strip electrodes located on both sides of the input light source and arranged asymmetrically with respect to the input light source in the y direction, form strip electrode pairs in pairs, and ensure that the heating power of the strip electrode pairs is always equal. At this time, the position of the output light spot has a certain offset in the y direction relative to the case where the strip electrode pairs are symmetrically distributed with respect to the input light source, thereby achieving the change of the position of the output light spot in the y direction;

[0027] and / or,

[0028] In the xoz plane, the output position, output angle, and output spot shape and size of the output beam can be adjusted continuously by combining the following three methods as needed:

[0029] Method 1: Select strip electrodes that are symmetrically arranged in the z direction with respect to the input light source, and form strip electrode pairs in pairs to ensure that the heating power of the strip electrodes is always equal. By adjusting the size of the heating power, the focal length of the waveguide lens is changed, thereby changing the size of the output light spot at a fixed output position;

[0030] Method 2: Select strip electrodes that are symmetrically arranged in the z direction with respect to the input light source, and form strip electrode pairs in pairs. Adjust the heating power of the strip electrode pairs to make them unequal, so that they have a certain angle deflection relative to the waveguide lens when the heating power is equal, thereby changing the deflection angle of the output light spot in the z direction at a fixed output position;

[0031] Method three: fix the position in the x direction, select strip electrodes located on both sides of the input light source and arranged asymmetrically with respect to the input light source in the z direction, form strip electrode pairs in pairs, and ensure that the heating power of the strip electrode pairs is always equal. At this time, the position of the output light spot has a certain offset in the z direction relative to the case where the strip electrode pairs are symmetrically distributed with respect to the input light source, thereby achieving the change of the position of the output light spot in the z direction.

[0032] Furthermore, the multimode waveguide is a two-dimensional waveguide or a three-dimensional waveguide, the two-dimensional waveguide is a single-mode waveguide in the third direction z, and the three-dimensional waveguide is a multi-mode waveguide in the third direction z.

[0033] Furthermore, the input waveguide includes a single-mode straight waveguide and an input wedge-shaped waveguide, and a wider section of the input wedge-shaped waveguide is connected to the input end of the multi-mode waveguide.

[0034] Furthermore, the input waveguide and the multimode waveguide are both located in the first core layer.

[0035] Furthermore, the waveguide lens type beam scanning and control device includes a first cladding, a first core layer and a second cladding; the first core layer is located between the first cladding and the second cladding; a plurality of strip electrodes are arranged at intervals along the second direction y and the third direction z, and are arranged in cascade in groups along the first direction x; the refractive index of the first core layer is greater than the refractive index of the first cladding and the second cladding.

[0036] Furthermore, a plurality of the waveguide lens type beam scanning and control devices are cascaded to form a waveguide lens type beam control device cascade component, and the optical switch controls the light beam of the input light source to enter the plurality of waveguide lens type beam scanning and control devices in sequence; or, the optical switch realizes beam splitting and enters the plurality of waveguide lens type beam scanning and control devices at the same time.

[0037] The beneficial effects of the present invention are as follows:

[0038] The present invention adopts a two-dimensional / three-dimensional multimode waveguide structure and adjusts the electrodes (groups) arranged around the multimode waveguide, so as to flexibly and continuously adjust the output position, output angle and output spot shape and size of the light beam, thereby effectively solving the problems of complex on-chip light beam control system and high cost of driving circuit, and can realize on-chip high-precision and multifunctional continuous light beam control function. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for describing the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention.

[0040] Figure 1 It is a schematic diagram of the structure of a waveguide lens type beam control device provided for an embodiment of the present application.

[0041] Figure 2 yes Figure 1 The waveguide lens type beam steering device is shown as a cross-sectional view along the first direction x and the second direction y.

[0042] Figure 3 yes Figure 1 The waveguide lens type beam control device is shown as a cross-sectional view along the second direction y and the second direction z.

[0043] Figure 4 This is a diagram of the simulation results of the temperature gradient generated by electrode heating in the waveguide lens type beam control device provided in the embodiment of the present application.

[0044] Figure 5 yes Figure 4 Refractive index distribution diagram of the temperature gradient generated by middle electrode heating in the third direction z.

[0045] Figure 6 This is a simulated light field diagram provided for an embodiment of the present application, in which the shape and size of the light spot output by adjusting the electrode is controlled in a two-dimensional multimode waveguide; wherein, in the diagram in the upper left corner, the heating powers of the upper and lower electrodes are equal, and are both 15mW; in the diagram in the upper right corner, the heating powers of the upper and lower electrodes are equal, and are both 25mW; in the diagram in the lower left corner, the heating powers of the upper and lower electrodes are equal, and are both 35mW; in the diagram in the lower right corner, the heating powers of the upper and lower electrodes are equal, and are both 45mW.

[0046] Figure 7 yes Figure 6 Simulation results of the change in beam spot shape and size under different upper and lower electrode spacings and heating powers.

[0047] Figure 8 This is a simulated light field diagram provided for an embodiment of the present application, in which the change in the output angle of the light beam is controlled by translating the upper and lower electrodes in a two-dimensional multimode waveguide; wherein the upper left corner shows the situation where the upper and lower electrodes are symmetrical about the input light beam; the upper right corner is a schematic diagram of the light beam output angle deflection when the upper and lower electrodes are jointly translated upward by 10 μm; the lower left corner is a schematic diagram of the light beam output angle deflection when the upper and lower electrodes are jointly translated upward by 20 μm; the lower right corner is a schematic diagram of the light beam output angle deflection when the upper and lower electrodes are jointly translated upward by 30 μm.

[0048] Fig. 9 yes Figure 8 Simulation results of the change in beam output angle under different waveguide lens optical axis positions and heating powers.

[0049] Fig.10 This is a design diagram of electrodes in a three-dimensional waveguide lens type beam control device provided in an embodiment of the present application.

[0050] Fig.11 It is a schematic diagram of an experimental measurement device for a three-dimensional waveguide lens type beam control device provided in an embodiment of the present application.

[0051] Fig.12 This is a graph of experimental measurement results of a three-dimensional waveguide lens type beam control device provided in an embodiment of the present application.

[0052] Fig.13 It is a schematic diagram of the structure of the cascade components of a two-dimensional waveguide lens type beam control device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0053] The present invention will be described in detail below based on the accompanying drawings and preferred embodiments, and the purpose and effects of the present invention will become more clear. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0054] Figure 1is a schematic diagram of the structure of a waveguide lens type beam control device provided in an example of the present application, Figure 2 yes Figure 1 A cross-sectional view of the beam control device along a first direction x and a second direction y, Figure 3 yes Figure 1 The beam control device is shown as a cross-sectional view along the second direction y and the third direction z.

[0055] refer to Figure 1 The waveguide lens type beam control device includes an input waveguide 10, a multimode waveguide 20 and a heating electrode 30 arranged around the multimode waveguide. The input waveguide 10 and the multimode waveguide 20 are arranged along a first direction x, and the input waveguide 10 is connected to the input end of the multimode waveguide 20. The input waveguide 10 and the multimode waveguide 20 are made of optical waveguide materials with thermo-optical effects, such as polymers, silica, etc. The input waveguide 10 includes a single-mode straight waveguide and an input wedge-shaped waveguide, and a wider section of the input wedge-shaped waveguide is connected to the input end of the multimode waveguide 20. The input waveguide can be composed of a single single-mode straight waveguide and an input wedge-shaped waveguide, or a combination of multiple single-mode straight waveguides and wedge-shaped waveguides. In this example, the input waveguide 10 has a wedge-shaped tapered structure, the function of which is to reduce the coupling loss between the input light source and the multimode waveguide 20 to achieve mode matching. It should be noted that the input waveguide 10 is not necessary, and the input light source can directly enter the multimode waveguide 20. Through the regulation of the strip electrode 30, the function of reducing the coupling loss between the input light source and the multimode waveguide can be equivalently achieved.

[0056] The multimode waveguide 20 is a two-dimensional waveguide or a three-dimensional waveguide. The two-dimensional waveguide is a waveguide that is a single-mode in the third direction z, and the three-dimensional waveguide is a waveguide that is a multi-mode in the third direction z.

[0057] refer to Figure 2 When the multimode waveguide is a two-dimensional multimode waveguide, the heating electrodes 30 in the waveguide lens type beam control device are arranged in cascade in groups along the first direction x, and are arranged at intervals along the second direction y perpendicular to the first direction x. Figure 3 As shown, when the multimode waveguide is a three-dimensional multimode waveguide, the plurality of strip electrodes 30 need to be arranged at intervals along a third direction z perpendicular to the first direction x and the second direction y.

[0058] Understandably, Figure 1-3 The arrangement of the strip electrodes 30 shown in the figure is only an example. The arrangement and quantity of the strip electrodes 30 can be designed in a variety of ways according to different light beam control requirements.

[0059] like Figure 3As shown, the waveguide chip includes a silicon substrate 70, a second cladding layer 60, a first core layer 50, a first cladding layer 40 and a strip electrode 30 which are arranged upward in sequence along a third direction z, and the input waveguide 10 and the multimode waveguide 20 are both located in the first core layer 50. The strip electrode 30 may be located above the first cladding layer 40, in the first cladding layer 40, in the first core layer 50, in the second cladding layer 60 and below the second cladding layer 60.

[0060] The working principle of the example of this application is based on the beam control of the thermo-optic waveguide lens (Thermo-Optic Waveguide Lens, TOWL) (group). The working principle will be specifically introduced below using a two-dimensional waveguide lens beam control device (Waveguide Lens BeamSteerer, WLBS) as an example.

[0061] Figure 4 The simulation results of different temperature distribution in the multimode waveguide on the yz section under two different heating electrodes (located above the first cladding 40) and power configurations are shown. Figure 4 In the above figure, the center coordinates of the strip electrode 30 are respectively located at (45, 7.8), (-45, 7.8), (0, 7.8); (45, -7.8), (-45, -7.8), (0, -7.8), Figure 4 In the figure below, the strip electrodes 30 are located at (45, 7.8), (-35, 7.8), (0, 7.8); (30, 0.1), (10, 0.1), (-80, 0.1); (25, -7.8), (-10, -7.8), (-60, -7.8). In the thermo-optical waveguide, the above-mentioned different temperature gradient changes can be further converted into the refractive index distribution changes of the multimode waveguide.

[0062] Figure 5 for Figure 4 The refractive index distribution curves of two different heating temperature gradients in the third direction z. It can be seen that the refractive index change caused by the strip electrodes presents a quadratic curve (combination) distribution in space. This quadratic refractive index distribution can achieve functions similar to those of traditional lenses, that is, it can collimate and expand the light beam, change the spot size and emission direction, etc. By selecting different strip electrodes and adjusting the heating power, the aperture (D), focal length (L), optical axis position (Axis) and other parameters of the thermal optical waveguide lens can be effectively changed, thereby realizing complex and flexible beam control functions.

[0063] Next, a specific implementation of controlling the beam scanning and control method by adjusting the strip electrode 30 in a waveguide lens type beam control device will be introduced.

[0064] When the position of the input light source remains unchanged, the output position, output angle and output spot shape of the light beam can be continuously adjusted by changing the position of the strip electrode 30 relative to the input light source and the heating power of the strip electrode 30 .

[0065] Specifically:

[0066] (a) Change the size of the output light spot

[0067] In the xoy plane, strip electrodes are arranged symmetrically in the y direction with respect to the input light source, and two of them form strip electrode pairs to ensure that the heating power of the strip electrode pairs is always equal. By adjusting the size of the heating power, the focal length of the waveguide lens is changed, thereby changing the size of the output light spot at a fixed output position;

[0068] and / or,

[0069] In the xoz plane, strip electrodes are selected that are arranged symmetrically in the z direction with respect to the input light source, and pairs of strip electrodes are formed to ensure that the heating power of the strip electrodes is always equal. By adjusting the heating power, the focal length of the waveguide lens is changed, thereby changing the size of the output light spot at a fixed output position.

[0070] (b) In the xoy plane, strip electrodes are selected to be arranged symmetrically in the y direction with respect to the input light source, and two of them form strip electrode pairs. The heating power of the strip electrode pairs is adjusted to be unequal, so that they have a certain angle deflection relative to the waveguide lens when the heating power is equal, thereby changing the deflection angle of the output light spot in the y direction at a fixed output position;

[0071] and / or,

[0072] In the xoz plane, strip electrodes are selected to be arranged symmetrically in the z direction with respect to the input light source, and pairs of strip electrodes are formed. The heating powers of the strip electrode pairs are adjusted to be unequal, so that they have a certain angle deflection relative to the waveguide lens when the heating powers are equal, thereby changing the deflection angle of the output light spot in the z direction at a fixed output position.

[0073] (c) Change the position of the output light spot in the y or z direction

[0074] In the xoy plane, the x-direction position is fixed, and strip electrodes located on both sides of the input light source and arranged asymmetrically with respect to the input light source are selected in the y direction, and two of them form strip electrode pairs, and the heating power of the strip electrode pairs is ensured to be always equal. At this time, the position of the output light spot is offset in the y direction relative to the case where the strip electrode pairs are symmetrically distributed with respect to the input light source, thereby achieving the change of the position of the output light spot in the y direction;

[0075] and / or,

[0076] In the xoz plane, the x-direction position is fixed, and in the z-direction, strip electrodes located on both sides of the input light source and asymmetrically arranged with respect to the input light source are selected to form strip electrode pairs in pairs, and it is ensured that the heating power of the strip electrode pairs is always equal. At this time, the position of the output light spot has a certain offset in the z-direction relative to the case where the strip electrode pairs are symmetrically distributed with respect to the input light source, thereby achieving the change of the position of the output light spot in the z-direction.

[0077] (d) Through the combination of (a), (b) and (c), the continuous adjustment of any combination of the output position, output angle and output spot shape and size of the output light beam can be achieved.

[0078] Figure 6 The simulation results of the waveguide lens controlling the output spot size of the light beam under four heating powers of 15mW, 25mW, 35mW and 45mW for a strip electrode pair 30 are shown. It can be seen that the greater the heating power (the heating power of the two electrodes is equal), the smaller the spot diameter of the output spot.

[0079] Figure 7 The left figure shows the output spot diameter results under different heating powers (15-45 mW) and electrode spacing D (40-80 μm) in the simulation. Figure 7 The figure on the right more intuitively shows the range of output spot diameters under different heating powers for the above-mentioned different electrode spacings. It can be seen that when the electrode spacing is 40μm, the output spot diameter can be continuously adjusted by precisely adjusting the heating power, and the changeable output spot diameter is in the range of 29 to 49μm. When the electrode spacing is 50μm, the output spot diameter ranges from 33 to 54μm. It can be understood that when the electrode spacing is 50μm, the maximum output spot diameter of the electrode spacing of 40μm can be covered. Therefore, by increasing the electrode spacing and adjusting the heating power of the two electrodes, continuous adjustment of the output spot diameter from 29 to 74μm can be achieved. It should be noted that Figure 6 and Figure 7 The above is only one embodiment of the present invention, and the actual adjustment range of the spot diameter can be changed by a more complex electrode design.

[0080] Figure 8 The first two rows of figures show the simulation results of the waveguide lens controlling the output angle of the beam under the action of a pair of strip electrodes 30, where one electrode has a fixed heating power (25mW) and the other electrode has different heating powers (30mW, 35mW, 40mW, 45mW). It can be seen that when the heating powers of the two electrodes are different, the beam will be "deflected" to the side of the electrode with lower heating power.

[0081] Figure 8The last two rows of figures show the simulation results of the output light spot when the heating power of the two electrodes remains unchanged and the symmetry center of the electrodes is shifted relative to the beam input (0μm, 10μm, 20μm, 30μm) under the action of a stack of strip electrodes 30. It can be seen that the position and output angle of the output light spot have changed at this time.

[0082] Fig. 9 The left figure shows the simulation results of the output angle size under different strip electrode offsets and heating powers. Fig. 9 The figure on the right more intuitively shows the range of output spot diameters for the above-mentioned different electrode spacings at different heating powers. It can be seen that when the offset shift = 5μm, continuous deflection of 0.8° to 3.0° can be achieved by precisely adjusting the heating power. When the offset shift = 10μm, continuous deflection of 2.1° to 4.3° can be achieved. It can be understood that when the offset shift = 10μm, the maximum deflection angle of shift = 5μm can be covered. Therefore, by increasing the offset shift and adjusting the power of the two electrodes, continuous adjustment of the deflection angle from 0.0° to 9.1° can be achieved. When changing the output beam angle by offset, the strip electrode can also continuously control the position of the output beam (based on the center of the output spot), such as Figure 8 As shown in the last two lines of . It can be understood that by flexibly selecting different offset electrode pairs and different heating powers, the output light spot position and deflection angle can be adjusted separately. It should be noted that Figure 8 and Fig. 9 The above is only one embodiment of the present invention, and the actual deflection angle and position can be changed by more complex electrode design.

[0083] It should be noted that when the light beam enters the air (free space) from the output waveguide, it satisfies Snell's refractive index law, that is, n1sinθ i =n2sinθ t . Where n1 is the refractive index of the multimode waveguide and n2 is the refractive index of air. θ i is the incident angle of the light beam at the interface between the waveguide and air, θ t is the refraction angle of the light beam. Since the refractive index of the multimode waveguide is greater than that of the air, when the light beam is incident from the multimode waveguide into the air, its output angle will be further amplified.

[0084] For example, Fig.10 A design of a three-dimensional waveguide lens type beam scanning control device is provided. The device has a two-stage cascade arrangement (x1, x2) in a first direction x, an 8-electrode spacing arrangement and a 16-electrode spacing arrangement in a second direction y, and a two-stage spacing arrangement (z1, z2) in a third direction z.

[0085] For example, Fig.11 A measurement method for a waveguide lens type beam control device is demonstrated. By imaging the output waveguide end face, the change of the spot position in two-dimensional space under different strip electrodes and power configurations can be observed experimentally. The results are shown in Figure 2. Fig.12 shown.

[0086] It is understandable that through Figure 6-12 The simulation and experiments in this paper show that waveguide lens-type beam control devices can effectively perform complex control of beams and realize diverse functions.

[0087] For example, Fig.13 As shown, an embodiment of a cascade component of a waveguide lens type beam control device is provided. Multiple two-dimensional / three-dimensional cascaded waveguide lens type beam control devices can be cascaded to achieve more complex functions, such as accurate scanning in a larger angle range. These waveguide lens type beam control devices themselves have a certain angle with the output surface. Since the device itself has continuous angle adjustment within a certain range, continuous regulation within a large angle range can be achieved through the above-mentioned combined design. The design parameters of these waveguide lens type beam control devices can be the same or different.

[0088] The following is an example of how the cascade components work: It can be seen that the light source is first input into the TOWL optical switch, which can control the light beam to enter different waveguide lens type beam scanning and control device units (P1-P12).

[0089] Working mode 1: After the input light source enters the optical switch, the paths are switched to the P1-P12 control units in sequence. When the light enters each waveguide lens type beam scanning and control device, the angle range covered by the current device is scanned one by one through the control electrode. When the angle scan of a device is completed, the input optical switch is configured uniformly to switch the input beam to the next device to complete all scans in sequence. The advantage of this working mode is that it can cover all angle scans within the range, but the disadvantage is that it takes a long time to complete the overall scan.

[0090] Working mode 2: After the input light source enters the optical switch, the optical switch device controls the beam splitting function, and the split light signal can enter the control unit P1-P12 at the same time. At this time, the echo signal can be processed in real time in combination with software analysis. When the main scanning target or obstacle is identified, it switches to the angle range near the target for precise scanning. The advantage of this working mode is that the scanning time is fast, the target port position can be quickly known, and the preliminary modeling can be completed. The disadvantage is that the scanning accuracy is reduced.

[0091] It should be noted that the design and working mode of the above cascade components are only one of the specific embodiments. In actual applications, various device designs and different working modes can be used according to actual application requirements.

[0092] Those skilled in the art can understand that the above are only preferred examples of the invention and are not intended to limit the invention. Although the invention is described in detail with reference to the above examples, those skilled in the art can still modify the technical solutions recorded in the above examples or replace some of the technical features therein with equivalents. Any modification, equivalent replacement, etc. made within the spirit and principle of the invention shall be included in the protection scope of the invention.

Claims

1. A waveguide lens type beam scanning and control method, characterized in that: The method is implemented based on a waveguide lens type beam scanning and control device; The waveguide lens type beam scanning and control device comprises: an input waveguide, a multimode waveguide and a plurality of strip electrodes located around the multimode waveguide; The input waveguide and the multimode waveguide are arranged in sequence along a first direction x, and the input waveguide is connected to an input end of the multimode waveguide, and an output end of the multimode waveguide is in contact with air; When the multimode waveguide is a two-dimensional multimode waveguide, a plurality of strip electrodes are arranged around the multimode waveguide and are arranged in cascade along a first direction x, and are arranged at intervals along a second direction y perpendicular to the first direction x; When the multimode waveguide is a three-dimensional multimode waveguide, the plurality of strip electrodes are also arranged at intervals along a third direction z perpendicular to the first direction x and the second direction y; The input waveguide and the multimode waveguide are made of optical waveguide materials with thermo-optical effect; When the position of the input light source remains unchanged, the output position, output angle and output spot shape of the light beam can be continuously adjusted by changing the position of the strip electrode relative to the input light source and the heating power of the strip electrode.

2. The waveguide lens type beam scanning and control method according to claim 1, characterized in that: In the xoy plane, strip electrodes are arranged symmetrically in the y direction with respect to the input light source, and two of them form strip electrode pairs to ensure that the heating power of the strip electrode pairs is always equal. By adjusting the size of the heating power, the focal length of the waveguide lens is changed, thereby changing the size of the output light spot at a fixed output position; and / or, In the xoz plane, strip electrodes are selected that are arranged symmetrically in the z direction with respect to the input light source, and pairs of strip electrodes are formed to ensure that the heating power of the strip electrodes is always equal. By adjusting the heating power, the focal length of the waveguide lens is changed, thereby changing the size of the output light spot at a fixed output position.

3. The waveguide lens type beam scanning and control method according to claim 1, characterized in that: In the xoy plane, strip electrodes are selected to be arranged symmetrically in the y direction with respect to the input light source, and two of them form strip electrode pairs. The heating power of the strip electrode pairs is adjusted to be unequal, so that they have a certain angle deflection relative to the waveguide lens when the heating power is equal, thereby changing the deflection angle of the output light spot in the y direction at a fixed output position; and / or, In the xoz plane, strip electrodes are selected to be arranged symmetrically in the z direction with respect to the input light source, and pairs of strip electrodes are formed. The heating powers of the strip electrode pairs are adjusted to be unequal, so that they have a certain angle deflection relative to the waveguide lens when the heating powers are equal, thereby changing the deflection angle of the output light spot in the z direction at a fixed output position.

4. The waveguide lens type beam scanning and control method according to claim 1, characterized in that: In the xoy plane, the x-direction position is fixed, and strip electrodes located on both sides of the input light source and arranged asymmetrically with respect to the input light source are selected in the y direction, and two of them form strip electrode pairs, and the heating power of the strip electrode pairs is ensured to be always equal. At this time, the position of the output light spot is offset in the y direction relative to the case where the strip electrode pairs are symmetrically distributed with respect to the input light source, thereby achieving the change of the position of the output light spot in the y direction; and / or, In the xoz plane, the x-direction position is fixed, and in the z-direction, strip electrodes located on both sides of the input light source and asymmetrically arranged with respect to the input light source are selected to form strip electrode pairs in pairs, and it is ensured that the heating power of the strip electrode pairs is always equal. At this time, the position of the output light spot has a certain offset in the z-direction relative to the case where the strip electrode pairs are symmetrically distributed with respect to the input light source, thereby achieving the change of the position of the output light spot in the z-direction.

5. The waveguide lens type beam scanning and control method according to claim 1, characterized in that: In the xoy plane, the output position, output angle, and output spot shape and size of the output beam can be adjusted continuously by combining the following three methods as needed: Method 1: Select strip electrodes that are symmetrically arranged in the y direction with respect to the input light source, and form strip electrode pairs in pairs to ensure that the heating power of the strip electrode pairs is always equal. By adjusting the size of the heating power, the focal length of the waveguide lens is changed, thereby changing the size of the output light spot. Method 2: Select strip electrodes that are symmetrically arranged in the y direction with respect to the input light source, form strip electrode pairs in pairs, and adjust the heating power of the strip electrode pairs to make them unequal, so that they have a certain angle deflection relative to the waveguide lens when the heating power is equal, thereby changing the deflection angle of the output light spot in the y direction; Method 3: fix the position in the x direction, select strip electrodes located on both sides of the input light source and arranged asymmetrically with respect to the input light source in the y direction, form strip electrode pairs in pairs, and ensure that the heating power of the strip electrode pairs is always equal. At this time, the position of the output light spot has a certain offset in the y direction relative to the case where the strip electrode pairs are symmetrically distributed with respect to the input light source, thereby achieving the change of the position of the output light spot in the y direction; and / or, In the xoz plane, the output position, output angle, and output spot shape and size of the output beam can be adjusted continuously by combining the following three methods as needed: Method 1: Select strip electrodes that are symmetrically arranged in the z direction with respect to the input light source, and form strip electrode pairs in pairs to ensure that the heating power of the strip electrodes is always equal. By adjusting the size of the heating power, the focal length of the waveguide lens is changed, thereby changing the size of the output light spot at a fixed output position; Method 2: Select strip electrodes that are symmetrically arranged in the z direction with respect to the input light source, and form strip electrode pairs in pairs. Adjust the heating power of the strip electrode pairs to make them unequal, so that they have a certain angle deflection relative to the waveguide lens when the heating power is equal, thereby changing the deflection angle of the output light spot in the z direction at a fixed output position; Method three: fix the position in the x direction, select strip electrodes located on both sides of the input light source and arranged asymmetrically with respect to the input light source in the z direction, form strip electrode pairs in pairs, and ensure that the heating power of the strip electrode pairs is always equal. At this time, the position of the output light spot has a certain offset in the z direction relative to the case where the strip electrode pairs are symmetrically distributed with respect to the input light source, thereby achieving the change of the position of the output light spot in the z direction.

6. The waveguide lens type beam scanning and control method according to claim 1, characterized in that: The multimode waveguide is a two-dimensional waveguide or a three-dimensional waveguide. The two-dimensional waveguide is a single-mode waveguide in a third direction z, and the three-dimensional waveguide is a multi-mode waveguide in the third direction z.

7. The waveguide lens type beam scanning and control method according to claim 1, characterized in that: The input waveguide comprises a single-mode straight waveguide and an input wedge-shaped waveguide, and a wider section of the input wedge-shaped waveguide is connected to the input end of the multi-mode waveguide.

8. The waveguide lens type beam scanning and control method according to claim 1, characterized in that: The input waveguide and the multimode waveguide are both located in the first core layer.

9. The waveguide lens type beam scanning and control method according to claim 1, characterized in that: The waveguide lens type beam scanning and control device includes a first cladding, a first core layer and a second cladding; the first core layer is located between the first cladding and the second cladding; a plurality of strip electrodes are arranged at intervals along the second direction y and the third direction z, and are arranged in cascade in groups along the first direction x; the refractive index of the first core layer is greater than the refractive index of the first cladding and the second cladding.

10. The waveguide lens type beam scanning and control method according to claim 1, characterized in that: A plurality of the waveguide lens type beam scanning and control devices are cascaded to form a waveguide lens type beam control device cascade component, and an optical switch is used to control the input light beam to enter the plurality of waveguide lens type beam scanning and control devices in sequence; or, the optical switch is used to implement beam splitting and simultaneously enter the plurality of waveguide lens type beam scanning and control devices.

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