A waveguide lens type light beam scanning and control method

Abstract

The application discloses a waveguide lens type light beam scanning and control method, which is realized based on a waveguide lens type light beam scanning and control device; the device comprises an input waveguide, a multimode waveguide and a plurality of strip electrodes arranged around the multimode waveguide; the input waveguide and the multimode waveguide are arranged along a direction x in sequence, the input waveguide is connected with 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, the electrodes are arranged around the multimode waveguide, arranged in cascade along the direction x, and arranged in interval along a direction y perpendicular to the direction x; when the multimode waveguide is a three-dimensional multimode waveguide, the electrodes are further arranged in interval along a direction z perpendicular to the directions x and y; when the position of an input light source is unchanged, the continuous adjustment of the output position, angle and spot size of the light beam is realized by changing the position of the electrodes relative to the light source and the heating power of the electrodes. The application can flexibly and continuously regulate and control the output position, angle and output spot size of the light beam.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of optical beam scanning and control, and in particular to a waveguide lens type optical beam scanning and control method. BACKGROUND

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

[0003] In related technologies, the commonly used optical beam control schemes mainly include mechanical type and micro-electro-mechanical systems (MEMS). These methods are usually used to adjust the output angle and position of the optical beam. However, the main disadvantage is that the volume is large, complex mechanical rotation and accurate calibration are required, and the service life of the device is limited. Another common scheme is the liquid crystal on silicon (LCoS) technology, which works by adjusting the liquid crystal layer to change the phase of the optical field, thereby adjusting the wavefront and phase surface to achieve control of the optical 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 the flexibility of its application. In addition, the adjustment accuracy of the above-mentioned devices is often limited by the number of unit devices, and continuous adjustment cannot be achieved in principle.

[0004] In contrast, photonic integrated circuits (PICs) based optical beam control devices have the advantages of small overall size, low power consumption and high integration. The common PIC type optical beam control device is an optical phased array (OPA). The concept of OPA comes from microwave phased array, which adjusts the phase on a plurality of waveguide arrays through optical phase shifters, thereby adjusting the wavefront and phase surface at the output end, and uses Fraunhofer diffraction to realize the emission of different angle beams to achieve scanning function. However, the adjustment 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 affects the overall imaging quality and requires complex electronic driving feedback adjustment. With the increase of the number of control waveguide arrays, the complexity and cost of the device also increase accordingly. Therefore, there is an urgent need in the field of optical beam control for a continuous optical beam scanning and control device with a relatively simple structure, high control freedom and wide angle coverage range to meet the needs of practical applications. SUMMARY

[0005] In view of the deficiencies of the prior art, the application 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, has flexible light beam control capability and can meet the requirements of light beam regulation and control in different scenes.

[0006] The object of the application is achieved by the following technical solutions:

[0007] A waveguide lens type light beam scanning and control method is realized based on a waveguide lens type light beam scanning and control device.

[0008] The waveguide lens type light beam scanning and control device comprises an input waveguide, a multimode waveguide and a plurality of strip electrodes arranged 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 with the input end of the multimode waveguide, and the 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 arranged in cascade along the first direction x and arranged in interval along a second direction y perpendicular to the first direction x.

[0011] When the multimode waveguide is a three-dimensional multimode waveguide, a plurality of strip electrodes are further arranged in interval 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 prepared from an optical waveguide material having a thermo-optic effect.

[0013] When the position of the input light source is unchanged, the continuous adjustment of the output position, output angle and output spot shape and size of the light beam is realized by changing the position of the strip electrode relative to the input light source and the heating power of the strip electrode.

[0014] Further, in the xoy plane, the strip electrodes symmetrically arranged in the y direction about the input light source are selected, and two-by-two strip electrode pairs are formed, the heating power of the strip electrode pairs is ensured to be always equal, the focal length of the waveguide lens is changed by adjusting the size of the heating power, and thus the size of the output spot is changed at the fixed output position.

[0015] And / or,

[0016] In the xoz plane, the strip electrodes symmetrically arranged in the z direction about the input light source are selected, and two-by-two strip electrode pairs are formed, the heating power of the strip electrodes is ensured to be always equal, the focal length of the waveguide lens is changed by adjusting the size of the heating power, and thus the size of the output spot is changed at the fixed output position.

[0017] Further, in the xoy plane, select the strip electrodes symmetrically arranged about the input light source in the y direction, two by two to form strip electrode pairs, adjust the heating power of the strip electrode pairs to be unequal, so that the waveguide lens has a certain angle deflection relative to the case of equal heating power, thereby changing the deflection angle of the output spot in the y direction at a fixed output position;

[0018] And / or,

[0019] In the xoz plane, select the strip electrodes symmetrically arranged about the input light source in the z direction, two by two to form strip electrode pairs, adjust the heating power of the strip electrode pairs to be unequal, so that the waveguide lens has a certain angle deflection relative to the case of equal heating power, thereby changing the deflection angle of the output spot in the z direction at a fixed output position.

[0020] Further, in the xoy plane, fix the x direction position, select the strip electrodes on both sides of the input light source and asymmetrically arranged about the input light source in the y direction, two by two to form strip electrode pairs, and ensure that the heating power of the strip electrode pairs is always equal, at this time the position of the output spot has a certain offset in the y direction relative to the case of symmetric distribution of the strip electrode pairs about the input light source, thereby realizing the change of the position of the output spot in the y direction;

[0021] And / or,

[0022] In the xoz plane, fix the x direction position, select the strip electrodes on both sides of the input light source and asymmetrically arranged about the input light source in the z direction, two by two to form strip electrode pairs, and ensure that the heating power of the strip electrode pairs is always equal, at this time the position of the output spot has a certain offset in the z direction relative to the case of symmetric distribution of the strip electrode pairs about the input light source, thereby realizing the change of the position of the output spot in the z direction.

[0023] Further, in the xoy plane, the following three ways are combined as needed to realize continuous adjustment of any combination of the output position, output angle, and output spot shape and size of the output light beam:

[0024] Method one: select the strip electrodes symmetrically arranged about the input light source in the y direction, two by two to form strip electrode pairs, and ensure that the heating power of the strip electrode pairs is always equal, change the focal length of the waveguide lens by adjusting the size of the heating power, thereby changing the size of the output spot;

[0025] Method two: select the strip electrodes symmetrically arranged about the input light source in the y direction, two by two to form strip electrode pairs, adjust the heating power of the strip electrode pairs to be unequal, so that the waveguide lens has a certain angle deflection relative to the case of equal heating power, thereby changing the deflection angle of the output spot in the y direction;

[0026] Mode three: fix the x-direction position, select the strip electrodes on both sides of the input light source and asymmetrically arranged about the input light source in the y-direction, form strip electrode pairs two by two, 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 symmetric distribution of the strip electrode pairs about the input light source, thereby realizing 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 light spot shape and size of the output light beam are continuously adjusted in any combination by the on-demand combination of the following three modes:

[0029] Mode one: select strip electrodes symmetrically arranged about the input light source in the z-direction, form strip electrode pairs two by two, and 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] Mode two: select strip electrodes symmetrically arranged about the input light source in the z-direction, form strip electrode pairs two by two, 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 z-direction at a fixed output position;

[0031] Mode three: fix the x-direction position, select the strip electrodes on both sides of the input light source and asymmetrically arranged about the input light source in the z-direction, form strip electrode pairs two by two, 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 symmetric distribution of the strip electrode pairs about the input light source, thereby realizing the change of the position of the output light spot in the z-direction.

[0032] Further, the multi-mode 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] Further, the input waveguide includes a single-mode straight waveguide and an input wedge-shaped waveguide. The wider section of the input wedge-shaped waveguide is connected to the input end of the multi-mode waveguide.

[0034] Further, the input waveguide and the multi-mode waveguide are both in the first core layer.

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

[0036] Further, a plurality of the waveguide lens type light beam scanning and control devices are cascaded to form a waveguide lens type light beam control device cascade component, and the light beams of the light source are input into the plurality of waveguide lens type light beam scanning and control devices in sequence by an optical switch; or, the optical switch is used to split the light beams and simultaneously input the light beams into the plurality of waveguide lens type light beam scanning and control devices.

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

[0038] By adopting the two-dimensional / three-dimensional multi-mode waveguide structure and regulating and controlling the electrodes (groups) arranged around the multi-mode waveguide, the output position, output angle and output spot shape and size of the light beam can be flexibly and continuously regulated and controlled, so that the problems of complex on-chip light beam control system and high cost of driving circuit can be effectively solved, and the on-chip high-precision and multi-functional continuous light beam control function can be realized. BRIEF DESCRIPTION OF DRAWINGS

[0039] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application.

[0040] Figure 1 FIG. 1 is a structural schematic diagram of a waveguide lens type light beam control device according to an embodiment of the present application.

[0041] Figure 2 FIG. 2 is a sectional view of the waveguide lens type light beam control device along the first direction x and the second direction y. Figure 1

[0042] Figure 3 FIG. 3 is a sectional view of the waveguide lens type light beam control device along the second direction y and the third direction z. Figure 1

[0043] Figure 4 FIG. 4 is a simulation result diagram of the temperature gradient generated by the electrode heating in the waveguide lens type light beam control device according to the embodiment of the present application.

[0044] Figure 5 FIG. 5 is a refractive index distribution diagram of the temperature gradient generated by the electrode heating in the third direction z. Figure 4

[0045] ​​​Figure 6 is the simulation light field diagram provided by the embodiment of the present application, in which the two-dimensional multi-mode waveguide, the light spot shape and size of the light beam output are controlled by adjusting the electrodes; in the upper left corner, the heating power of the upper and lower electrodes is equal, and is 15 mW; in the upper right corner, the heating power of the upper and lower electrodes is equal, and is 25 mW; in the lower left corner, the heating power of the upper and lower electrodes is equal, and is 35 mW; in the lower right corner, the heating power of the upper and lower electrodes is equal, and is 45 mW.

[0046] Figure 7 is Figure 6 is the simulation result diagram of the light spot shape and size change of the light beam under different upper and lower electrode spacings and heating powers.

[0047] Figure 8 is the simulation light field diagram provided by the embodiment of the present application, in which the two-dimensional multi-mode waveguide, the light spot shape and size of the light beam output are controlled by adjusting the electrodes; in the upper left corner, the heating power of the upper and lower electrodes is equal, and is 15 mW; in the upper right corner, the heating power of the upper and lower electrodes is equal, and is 25 mW; in the lower left corner, the heating power of the upper and lower electrodes is equal, and is 35 mW; in the lower right corner, the heating power of the upper and lower electrodes is equal, and is 45 mW.

[0048] Figure 9 is Figure 8 is the simulation result diagram of the light spot shape and size change of the light beam under different upper and lower electrode spacings and heating powers.

[0049] Figure 10 is the electrode design diagram of the three-dimensional waveguide lens type light beam control device provided by the embodiment of the present application.

[0050] Figure 11 is the experimental measurement device schematic diagram of the three-dimensional waveguide lens type light beam control device provided by the embodiment of the present application.

[0051] Figure 12 is the experimental measurement result diagram of the three-dimensional waveguide lens type light beam control device provided by the embodiment of the present application.

[0052] Figure 13 is the cascade component structure schematic diagram of the two-dimensional waveguide lens type light beam control device provided by the embodiment of the present application. DETAILED DESCRIPTION

[0053] The purpose and effect of the present application will become more apparent from the following detailed description of the drawings and preferred embodiments, and it should be understood that the specific embodiments described herein are only used to explain the present application and do not limit the present application.

[0054] Figure 1is a structural schematic diagram of a waveguide lens type light beam control device provided by an embodiment of the present application, Figure 2 is Figure 1 is a sectional view of the light beam control device along a first direction x and a second direction y, Figure 3 is Figure 1 is a sectional view of the light beam control device along a second direction y and a third direction z.

[0055] Referring to Figure 1 , the waveguide lens type light beam control device comprises 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 end of 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 an optical waveguide material having a thermo-optic effect, such as a polymer, silica, etc. The input waveguide 10 comprises a single-mode straight waveguide and an input wedge-shaped waveguide, and the 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 embodiment, the input waveguide 10 has a wedge-shaped taper structure, which functions to reduce the coupling loss between the input light source and the multimode waveguide 20 and 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, and 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 single-mode in the third direction z, and the three-dimensional waveguide is a waveguide that is multi-mode in the third direction z.

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

[0058] It can be understood that Figures 1-3 The arrangement of the strip electrodes 30 shown in the above is only an example, and the arrangement and number of the strip electrodes 30 can be diversified designed according to different light beam control requirements.

[0059] As 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 arranged in sequence upwards along the 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 can 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 present application example is based on thermo-optic waveguide lens (TOWL) (group) beam control. The working principle will be specifically introduced below taking a two-dimensional waveguide lens beam steering device (WLBS) as an example.

[0061] Figure 4 Simulation results of different temperature distributions in the multimode waveguide in the yz cross-section under two different heating electrodes (located above the first cladding layer 40) and power configurations are shown. Among them, Figure 4 In the upper graph of FIG. 1, the center coordinates of the strip electrode 30 are respectively (45, 7.8), (-45, 7.8), (0, 7.8); (45, -7.8), (-45, -7.8), (0, -7.8), Figure 4 In the lower graph of FIG. 1, the strip electrode 30 is respectively 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-optic waveguide, the above different temperature gradient changes can be further converted into the refractive index distribution change of the multimode waveguide.

[0062] Figure 5 For Figure 4 The refractive index distribution curves of the two different heating temperature gradient distributions in the third direction z in FIG. 1. It can be seen that the refractive index change caused by the strip electrode presents a quadratic curve (combination) distribution in space. This quadratic refractive index distribution can realize the functions similar to traditional lenses, that is, it can realize beam collimation, beam expansion, change of spot size and exit direction and other functions. 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 thermo-optic waveguide lens can be effectively changed, so as to realize complex and flexible beam control functions.

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

[0064] When the position of the input light source is unchanged, the output position, output angle and output spot shape and size of the light beam are continuously adjusted by changing the position of the strip electrodes 30 relative to the input light source and the heating power of the strip electrodes 30.

[0065] Specifically,

[0066] (a) changing the size of the output spot

[0067] In the xoy plane, the strip electrodes are selected to be symmetrically arranged about the input light source in the y direction, and two-by-two strip electrode pairs are formed to ensure that the heating power of the strip electrode pairs is always equal. The focal length of the waveguide lens is changed by adjusting the size of the heating power, thereby changing the size of the output spot at a fixed output position.

[0068] and / or,

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

[0070] (b) In the xoy plane, the strip electrodes are selected to be symmetrically arranged about the input light source in the y direction, and two-by-two strip electrode pairs are formed. The heating power of the strip electrode pairs is adjusted to be unequal, so that the waveguide lens has a certain angle deflection relative to the waveguide lens when the heating power is equal. Thus, the deflection angle of the output spot in the y direction is changed at a fixed output position.

[0071] and / or,

[0072] In the xoz plane, the strip electrodes are selected to be symmetrically arranged about the input light source in the z direction, and two-by-two strip electrode pairs are formed. The heating power of the strip electrode pairs is adjusted to be unequal, so that the waveguide lens has a certain angle deflection relative to the waveguide lens when the heating power is equal. Thus, the deflection angle of the output spot in the z direction is changed at a fixed output position.

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

[0074] In the xoy plane, the x direction position is fixed, and the strip electrodes are selected to be asymmetrically arranged about the input light source on both sides of the input light source in the y direction, two-by-two strip electrode pairs are formed, and the heating power of the strip electrode pairs is always equal. At this time, the position of the output spot has a certain offset in the y direction relative to the case where the strip electrode pairs are symmetrically distributed about the input light source, thereby realizing the change of the position of the output spot in the y direction.

[0075] and / or,

[0076] In the xoz plane, fix the x direction position, select the strip electrodes which are located on both sides of the input light source and are asymmetrically arranged about the input light source in the z direction, form strip electrode pairs two by two, 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 output light spot is symmetrically distributed about the input light source with respect to the strip electrode pairs, so as to change the position of the output light spot in the z direction.

[0077] (d) By the combination of (a), (b) and (c), the continuous adjustment of any combination of the output position, the output angle, and the size of the output light spot of the output light beam is realized.

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

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

[0080] Figure 8 The first two rows of graphs show the simulation results of the waveguide lens controlling the output angle of the light beam at different heating powers (30 mW, 35 mW, 40 mW, 45 mW) of one pair of strip electrodes 30 when the heating power of one electrode is fixed (25 mW). It can be seen that when the heating powers of the two electrodes are different, the light 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 spot when the two electrodes are arranged with a shift offset (0 μm, 10 μm, 20 μm, 30 μm) relative to the light beam input under the action of a stack of strip electrodes 30 with unchanged heating power of the electrodes. It can be seen that the position and the output angle of the output spot have changed.

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

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

[0084] An example is provided. Figure 10 A design of a three-dimensional waveguide lens type light beam scanning control device is provided. The device is arranged in two stages (x1, x2) in the first direction x, presents 8 electrode interval arrangements and 16 electrode interval arrangements in the second direction y respectively, and is arranged in two stages (z1, z2) in the third direction z.

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

[0086] It can be understood that through the simulation and experimental explanation in Figures 6-12 , the waveguide lens type beam control device can effectively control the beam and achieve diversified functions.

[0087] An example, as shown in Figure 13 , a waveguide lens type beam control device cascade component embodiment is provided. Multiple two-dimensional / three-dimensional cascaded waveguide lens type beam control devices can achieve more complex functions through cascading, such as achieving precise scanning in a larger angle range, etc. These waveguide lens type beam control devices themselves have a certain angle with the output face. Due to the continuous angle adjustment within a certain range of the device itself, through the above combination design, continuous regulation within a large angle range can be achieved. The design parameters of these waveguide lens type beam control devices can be the same or different.

[0088] The working mode of this cascade component will be introduced by example. 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, it is switched to the P1-P12 control unit 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 scanning of a device is completed, the input light beam is switched to the next device by the input optical switch for unified configuration, and the whole scanning is completed in turn. The advantage of this working mode is that it can cover all angle scanning within the range, and the disadvantage is that the time to complete the whole scanning is relatively slow.

[0090] Working mode 2: After the input light source enters the optical switch, the beam splitting function is realized by the optical switch device control, and the split light signal can enter the control units 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 distinguished, the angle range near the target is switched to for accurate scanning. The advantage of this working mode is that the scanning time is fast, and the target port position can be quickly obtained to complete the preliminary modeling. The disadvantage is that the scanning accuracy is reduced.

[0091] It should be noted that the design and working mode of the cascade component described above is only one of the specific embodiments in the actual application. In actual application, diversified device designs and different working modes can be adopted according to actual application needs.

[0092] Those skilled in the art can understand that the above description is only a preferred example of the application and is not used to limit the application. Although the application is described in detail with reference to the foregoing examples, those skilled in the art can still modify the technical solutions recorded in the foregoing examples or make equivalent replacements for part of the technical features. Any modification, equivalent replacement, etc. made within the spirit and principle of the application shall be included in the protection scope of the application.

Claims

1. A waveguide lens type beam scanning and controlling method, characterized by, The method is based on a waveguide lens type light beam scanning and control device; The waveguide lens type light beam scanning and control device comprises an input waveguide, a multimode waveguide and a plurality of strip electrodes arranged 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 with the input end of the multimode waveguide, and the 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 arranged in cascade along a first direction x and arranged in interval 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 in interval 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 an optical waveguide material with a thermo-optic effect; When the position of the input light source is unchanged, the output position, the output angle and the output spot shape and size of the light beam are 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 light beam scanning and control method according to claim 1, wherein, in the xoy plane, the strip electrodes symmetrically arranged in the y direction relative to the input light source are selected, and two-by-two strip electrode pairs are formed to ensure that the heating power of the strip electrode pairs is always equal, and the focal length of the waveguide lens is changed by adjusting the size of the heating power, so as to change the size of the output spot at the fixed output position; and / or, in the xoz plane, the strip electrodes symmetrically arranged in the z direction relative to the input light source are selected, and two-by-two strip electrode pairs are formed to ensure that the heating power of the strip electrodes is always equal, and the focal length of the waveguide lens is changed by adjusting the size of the heating power, so as to change the size of the output spot at the fixed output position.

3. The waveguide lens type light beam scanning and control method according to claim 1, wherein, in the xoy plane, the strip electrodes symmetrically arranged in the y direction relative to the input light source are selected, and two-by-two strip electrode pairs are formed, and the heating power of the strip electrode pairs is adjusted to be unequal, so that the waveguide lens has a certain angle deflection relative to the waveguide lens when the heating power is equal, so as to change the deflection angle of the output spot in the y direction at the fixed output position; and / or, in the xoz plane, the strip electrodes symmetrically arranged in the z direction relative to the input light source are selected, and two-by-two strip electrode pairs are formed, and the heating power of the strip electrode pairs is adjusted to be unequal, so that the waveguide lens has a certain angle deflection relative to the waveguide lens when the heating power is equal, so as to change the deflection angle of the output spot in the z direction at the fixed output position.

4. The waveguide lens type light beam scanning and control method according to claim 1, wherein, ​ ​ ​ ​ ​ ​ In the xoy plane, the x-direction position is fixed, the strip electrodes on both sides of the input light source and arranged asymmetrically about the input light source are selected in the y-direction, two by two to form strip electrode pairs, and 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 symmetric distribution of the strip electrode pairs about the input light source, so as to change the position of the output light spot in the y-direction. And / or, In the xoz plane, the x-direction position is fixed, the strip electrodes on both sides of the input light source and arranged asymmetrically about the input light source are selected in the z-direction, two by two to form strip electrode pairs, and 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 symmetric distribution of the strip electrode pairs about the input light source, so as to change the position of the output light spot in the z-direction.

5. The waveguide lens type light beam scanning and control method according to claim 1, wherein, In the xoy plane, the x-direction position is fixed, the strip electrodes on both sides of the input light source and arranged asymmetrically about the input light source are selected in the y-direction, two by two to form strip electrode pairs, and 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 symmetric distribution of the strip electrode pairs about the input light source, so as to change the position of the output light spot in the y-direction. And / or, In the xoz plane, the x-direction position is fixed, the strip electrodes on both sides of the input light source and arranged asymmetrically about the input light source are selected in the z-direction, two by two to form strip electrode pairs, and 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 symmetric distribution of the strip electrode pairs about the input light source, so as to change the position of the output light spot in the z-direction.

5. The waveguide lens type light beam scanning and control method according to claim 1, wherein, In the xoy plane, the x-direction position is fixed, the strip electrodes on both sides of the input light source and arranged asymmetrically about the input light source are selected in the y-direction, two by two to form strip electrode pairs, and 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 symmetric distribution of the strip electrode pairs about the input light source, so as to change the position of the output light spot in the y-direction. And / or, In the xoz plane, the x-direction position is fixed, the strip electrodes on both sides of the input light source and arranged asymmetrically about the input light source are selected in the z-direction, two by two to form strip electrode pairs, and 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 symmetric distribution of the strip electrode pairs about the input light source, so as to change the position of the output light spot in the z-direction. ​ The third mode is to fix the x-direction position, select the strip electrodes on both sides of the input light source and asymmetrically arranged with respect to the input light source in the z-direction, form strip electrode pairs two by two, 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 symmetric distribution of the strip electrode pairs with respect to the input light source, thereby changing the position of the output light spot in the z-direction.

6. The waveguide lens type beam scanning and controlling method according to claim 1, wherein, The multi-mode 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.

7. The waveguide lens type beam scanning and controlling method according to claim 1, wherein, 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 with the input end of the multi-mode waveguide.

8. The waveguide lens type beam scanning and controlling method according to claim 1, wherein, The input waveguide and the multi-mode waveguide are both in the first core layer.

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

10. The waveguide lens type beam scanning and controlling method according to claim 1, wherein, A plurality of the waveguide lens type light beam scanning and control devices are cascaded to form a waveguide lens type light 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 light beam scanning and control devices in sequence; or the optical switch is used to split the light beam and simultaneously enter the plurality of waveguide lens type light beam scanning and control devices.

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