Multiband optical phased array and preparation method thereof

Abstract

The invention provides a multiband optical phased array and a preparation method, and relates to the technical field of photoelectricity. The multiband optical phased array comprises a substrate; the array waveguide units are arranged on the substrate and used for carrying out phase modulation on input optical signals of at least one wavelength, the number of the array waveguide units is the same as that of the input optical signals of the at least one wavelength, and the optical signals of the at least one wavelength are correspondingly input into the array waveguide units; and the optical antenna is vertically connected with the array waveguide unit, is separated from the substrate, and is used for transmitting the received phase-modulated optical signal of at least one wavelength.

Description

Technical Field

[0001] The present disclosure relates to the field of optoelectronic technology, and more specifically, to a multi-band optical phased array and a preparation method thereof. Background Art

[0002] Optical Phased Array (OPA) is an advanced beam pointing control technology that achieves non-mechanical electrical adjustment of the beam direction by precisely controlling the light wave characteristics in multiple phased array units.

[0003] Optical phased arrays have shown great potential in many fields due to their unique advantages: high precision, fast response, and no mechanical moving parts, such as laser radar, laser printing, space optical communications, and medical imaging, as well as other military and civilian fields.

[0004] Although optical phased array technology has made significant progress, it still faces some challenges. In particular, the problem of low integration. Existing optical phased array devices usually contain only a limited number of phased array units, which limits their application range and the possibility of performance improvement. Achieving high-density integration is essential for realizing complex functions and reducing costs. And the problem of single wavelength operation: Existing optical phased arrays can only process beams of a single wavelength, which limits their ability to operate at multiple wavelengths, thus affecting their applicability in certain complex application scenarios. Summary of the invention

[0005] In view of this, the present disclosure provides a multi-band optical phased array and a preparation method thereof.

[0006] On the one hand, the present disclosure provides a multi-band optical phased array, including: a substrate; an array waveguide unit, which is arranged on the substrate and is used to modulate the phase of an input optical signal of at least one wavelength, wherein the number of the array waveguide units is the same as the number of the input optical signals of at least one wavelength, and the optical signal of at least one wavelength is input into the array waveguide unit accordingly; an optical antenna, which is arranged to be vertically connected to the array waveguide unit and is separated from the substrate, and is used to transmit the received phase-modulated optical signal of at least one wavelength.

[0007] According to an embodiment of the present disclosure, the multi-band optical phased array further includes: a phase shift control circuit, which is disposed on a surface of the substrate away from the array waveguide unit and is used to drive the array waveguide unit to modulate the phase of an input optical signal of at least one wavelength.

[0008] According to an embodiment of the present disclosure, the waveguide unit includes: a plurality of phase-shifting electrodes and a plurality of waveguide structures; wherein a phase-shifting electrode is provided on both sides of each waveguide structure.

[0009] According to an embodiment of the present disclosure, the multi-band optical phased array further includes: a plurality of optical waveguide amplifiers, which are arranged between the array waveguide unit and the optical antenna, wherein each optical waveguide amplifier is correspondingly connected to an output end of each waveguide structure.

[0010] According to an embodiment of the present disclosure, the multi-band optical phased array further includes: a plurality of lasers, each laser being connected to a corresponding waveguide unit in the array waveguide unit and configured to output an optical signal of at least one wavelength.

[0011] According to an embodiment of the present disclosure, the optical antenna includes: a plurality of antenna units, the number of the plurality of antenna units is the same as the number of output ends of the plurality of waveguide structures, and each antenna unit is correspondingly connected to the output end of each optical waveguide amplifier.

[0012] According to an embodiment of the present disclosure, the multi-band optical phased array further includes: an optical fiber array, the number of the optical fiber array is the same as the number of the multiple antenna units, wherein each optical fiber in the optical fiber array connects the output end of each optical waveguide amplifier to each antenna unit accordingly.

[0013] According to an embodiment of the present disclosure, the multi-band optical phased array further includes: lens optical fibers, which are arranged at both ends of each optical fiber, one end of which is connected to the output end of the optical waveguide amplifier, and the other end is connected to the antenna unit.

[0014] According to an embodiment of the present disclosure, the material of the optical waveguide amplifier includes erbium-doped lithium niobate; and the material of the arrayed waveguide unit includes lithium niobate.

[0015] The second aspect of the present disclosure discloses a method for preparing a multi-band optical phased array, comprising: bonding a lithium niobate film on a substrate; etching the lithium niobate film to prepare an array waveguide unit; vertically connecting the array waveguide structure to an optical antenna; wherein the array waveguide unit is used to modulate the phase of an input optical signal of at least one wavelength, wherein the number of the array waveguide units is the same as the number of the input optical signals of at least one wavelength, and the optical signal of at least one wavelength is input correspondingly into the array waveguide unit; and the optical antenna is separated from the substrate and is used to transmit the received phase-modulated optical signal of at least one wavelength.

[0016] According to the embodiments of the present disclosure, by vertically connecting the optical antenna to the array waveguide unit, the integration per unit area is effectively improved, the size of the device is reduced, and the device is more suitable for large-scale production and application.

[0017] According to the embodiments of the present disclosure, by providing a multi-wavelength light source, a plurality of light beams of different wavelengths are processed simultaneously on the same phased array platform, thereby achieving multi-wavelength operation and significantly expanding the functionality and flexibility of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above and other objects, features and advantages of the present disclosure will become more apparent through the following description of the embodiments of the present disclosure with reference to the accompanying drawings, in which:

[0019] Figure 1 The structure diagram of the multi-band optical phased array of the embodiment of the present disclosure is schematically shown;

[0020] Figure 2 A schematic diagram of the structure of a multi-band optical unit according to an embodiment of the present disclosure is shown;

[0021] Description of reference numerals:

[0022] 1. Substrate; 2. Arrayed waveguide unit; 2-1. Phase shift electrode; 2-2. Waveguide structure; 2-3. Beam splitter; 3. Optical antenna; 3-1. Antenna unit; 4. Optical waveguide amplifier unit; 4-1 Optical waveguide amplifier; 5. Laser unit; 5-1. Laser; 6. Optical fiber; 7. Phase shift control circuit; 8. Photonic lead. DETAILED DESCRIPTION

[0023] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the present disclosure. In the following detailed description, for ease of explanation, many specific details are set forth to provide a comprehensive understanding of the embodiments of the present disclosure. However, it is apparent that one or more embodiments may also be implemented without these specific details. In addition, in the following description, descriptions of known systems and technologies are omitted to avoid unnecessary confusion of the concepts of the present disclosure.

[0024] The terms used herein are only for describing specific embodiments and are not intended to limit the present disclosure. The terms "comprise", "include", etc. used herein indicate the existence of features, steps, operations and / or components, but do not exclude the existence or addition of one or more other features, steps, operations or components.

[0025] All terms (including technical and scientific terms) used herein have the meanings commonly understood by those skilled in the art unless otherwise defined. It should be noted that the terms used herein should be interpreted as having a meaning consistent with the context of this specification and should not be interpreted in an idealized or overly rigid manner.

[0026] When using expressions such as "at least one of A, B, and C, etc.", they should generally be interpreted according to the meaning of the expression commonly understood by those skilled in the art (for example, "a system having at least one of A, B, and C" should include but is not limited to a system having A alone, B alone, C alone, A and B, A and C, B and C, and / or A, B, C, etc.).

[0027] Figure 1 The structural diagram of the multi-band optical phased array of an embodiment of the present disclosure is schematically shown.

[0028] like Figure 1 As shown, on one hand, the present disclosure provides a multi-band optical phased array, comprising: a substrate 1; an array waveguide unit 2, which is arranged on the substrate 1 and is used to modulate the phase of an input optical signal of at least one wavelength, wherein the number of the array waveguide units 2 is the same as the number of the input optical signals of at least one wavelength, and the optical signal of at least one wavelength is input into the array waveguide unit accordingly; an optical antenna 3, which is arranged to be vertically connected to the array waveguide unit and is separated from the substrate, and is used to transmit the received phase-modulated optical signal of at least one wavelength.

[0029] In the embodiments of the present disclosure, by introducing a multi-wavelength light source, multiple light beams of different wavelengths can be processed simultaneously on the same phased array platform, significantly expanding the functionality and flexibility of the system, and solving the problem that the existing system can only process a single wavelength of light beam, which limits its multi-wavelength operation capability and thus affects its applicability in certain complex application scenarios. The present disclosure improves the application in the field of multi-band laser radar by introducing a multi-wavelength light source on the same substrate.

[0030] The traditional optical array control structure is achieved by integrating the optical antenna and waveguide structure in parallel on the same substrate. This integration method results in a low integration density per unit area. The embodiment of the present disclosure effectively solves the problem of low integration density per unit area by vertically connecting the array waveguide unit to the optical antenna, and in the case of setting a multi-wavelength light source, it can effectively improve the integration density of the overall device and reduce the size of the device. At the same time, the modulated optical signal is emitted into the free space through the optical antenna, generating mutually reinforcing interference in the set direction to form a high-intensity light beam.

[0031] According to an embodiment of the present disclosure, the substrate may be a silicon substrate.

[0032] According to the embodiments of the present disclosure, the number of array waveguide units can be set as needed, and the corresponding optical antennas are also set according to the number of waveguide structures in the array waveguide units.

[0033] Figure 2 The structural diagram of the multi-band optical unit of an embodiment of the present disclosure is schematically shown.

[0034] like Figure 2 As shown, according to an embodiment of the present disclosure, the multi-band optical phased array further includes: a phase shift control circuit 7, which is arranged on a surface of the substrate 1 away from the array waveguide unit 2, and is used to drive the array waveguide unit to modulate the phase of an input optical signal of at least one wavelength.

[0035] According to an embodiment of the present disclosure, the waveguide unit includes: a plurality of phase-shifting electrodes and a plurality of waveguide structures; wherein a phase-shifting electrode 2-1 is provided on both sides of each waveguide structure 2-2.

[0036] In the embodiment of the present disclosure, the phase shifting electrodes in the array waveguide unit are driven by the phase shifting control circuit, and the effective refractive index of each waveguide structure is adjusted by applying different voltages, thereby achieving precise control of the phase of the optical signal. In addition, by arranging the phase shifting control circuit on the other surface of the substrate, compared with the traditional arrangement of arranging the phase shifting control circuit outside the device, the integration level and the utilization rate of the device space are effectively improved.

[0037] In some possible embodiments, the optical signal output by the laser is equally beamed by the beam splitter 2-3 to generate four light beams. The four light beams are phase-modulated based on the thermo-optical effect of the waveguide to output phase-modulated light beams.

[0038] According to an embodiment of the present disclosure, the multi-band optical phased array further includes: a plurality of optical waveguide amplifiers, which are arranged between the array waveguide unit and the optical antenna, wherein each optical waveguide amplifier is correspondingly connected to an output end of each waveguide structure.

[0039] In the embodiment of the present disclosure, the optical waveguide amplifier unit 4 is composed of a plurality of optical waveguide amplifiers 4-1. By arranging the optical waveguide amplifier unit between the array waveguide unit and the optical antenna, the attenuation loss of the optical signal during the waveguide transmission process can be effectively compensated, ensuring that the optical signal maintains sufficient intensity before reaching the optical antenna, which is conducive to long-distance transmission or high-power output. And the output ends of the plurality of optical waveguide amplifiers are arranged in a one-dimensional array with one row and N columns.

[0040] According to an embodiment of the present disclosure, the multi-band optical phased array further includes: a plurality of lasers, each laser being connected to a corresponding waveguide unit in the array waveguide unit and configured to output an optical signal of at least one wavelength.

[0041] In the embodiment of the present disclosure, a multi-wavelength light source can be provided by arranging a plurality of lasers 5-1 to form a laser unit 5. The laser is connected to a waveguide structure through a photon wire 8 bonding process to form a closed optical channel.

[0042] According to an embodiment of the present disclosure, the optical antenna includes: multiple antenna units 3-1, the number of the multiple antenna units 3-1 is the same as the number of output ends of the multiple waveguide structures 2-2, and each antenna unit is correspondingly connected to the output end of each optical waveguide amplifier 4-1.

[0043] In the embodiments of the present disclosure, the optical antenna adopts an M×N planar array layout, where M is the row and N is the column. Optical antennas of different wavebands adopt regional module multiplexing to achieve high-power, multi-beam directional transmission.

[0044] In the embodiments of the present disclosure, each antenna unit is responsible for sending an optical signal, and the phase of the optical signal is controlled through a waveguide structure to form a highly controllable light beam, which can achieve target emission in different directions. The structure of the optical antenna can be designed as needed, and is processed on-chip, using a module multiplexing layout to achieve the emission of multi-band optical signals in different directions.

[0045] According to an embodiment of the present disclosure, the multi-band optical phased array further includes: an optical fiber array, the number of which is the same as the number of the plurality of antenna units, wherein each optical fiber connects the output end of each optical waveguide amplifier to each antenna unit accordingly.

[0046] According to an embodiment of the present disclosure, the multi-band optical phased array further includes: lens optical fibers, which are arranged at both ends of each optical fiber, one end of which is connected to the output end of the optical waveguide amplifier, and the other end is connected to the antenna unit.

[0047] In the embodiment of the present disclosure, by using an optical fiber array to connect the output end of each optical waveguide amplifier to each antenna unit, the optical path coupling of the optical signal from one dimension to two dimensions is realized. At the same time, lens optical fibers are used at both ends of the optical fiber to achieve low-loss transmission of the signal.

[0048] According to the embodiments of the present disclosure, when there are too many light sources of different wavelengths, photon wire bonding can be used instead of optical fiber array to connect the output end of each optical waveguide amplifier to each antenna unit. This avoids the situation where the optical fiber array is used when there are too many light sources, which may cause the interface to be offset and the optical waveguide amplifier and the antenna unit to be connected accurately.

[0049] According to an embodiment of the present disclosure, the material of the optical waveguide amplifier includes erbium-doped lithium niobate; and the material of the arrayed waveguide unit includes lithium niobate.

[0050] The second aspect of the present disclosure discloses a method for preparing a multi-band optical phased array, comprising: bonding a lithium niobate film on a substrate; etching the lithium niobate film to prepare an array waveguide unit; vertically connecting the array waveguide structure to an optical antenna; wherein the array waveguide unit is used to modulate the phase of an input optical signal of at least one wavelength, wherein the number of the array waveguide units is the same as the number of the input optical signals of at least one wavelength, and the optical signal of at least one wavelength is input correspondingly into the array waveguide unit; and the optical antenna is separated from the substrate and is used to transmit the received phase-modulated optical signal of at least one wavelength.

[0051] In the embodiments of the present disclosure, the preparation method of the multi-band optical phased array is simple, the cost is reduced, and the coupling of the optical path from one dimension to two dimensions is realized, which reduces the coupling difficulty of the optical path and improves the coupling efficiency.

[0052] It will be appreciated by those skilled in the art that the features described in the various embodiments and / or claims of the present disclosure may be combined and / or combined in a variety of ways, even if such combinations and / or combinations are not explicitly described in the present disclosure. In particular, the features described in the various embodiments and / or claims of the present disclosure may be combined and / or combined in a variety of ways without departing from the spirit and teachings of the present disclosure. All of these combinations and / or combinations fall within the scope of the present disclosure.

[0053] The embodiments of the present disclosure are described above. However, these embodiments are only for illustrative purposes and are not intended to limit the scope of the present disclosure. Although the embodiments are described above separately, this does not mean that the measures in the various embodiments cannot be used in combination to advantage. The scope of the present disclosure is defined by the attached claims and their equivalents. Without departing from the scope of the present disclosure, those skilled in the art may make a variety of substitutions and modifications, which should all fall within the scope of the present disclosure.

Claims

1. A multi-band optical phased array, characterized in that: include: substrate; An array waveguide unit, arranged on the substrate, for performing phase modulation on an input optical signal of at least one wavelength, wherein the number of the array waveguide units is the same as the number of the input optical signal of at least one wavelength, and the optical signal of at least one wavelength is input into the array waveguide unit accordingly; An optical antenna is arranged to be vertically connected to the array waveguide unit and is separated from the substrate, and is used for transmitting the received optical signal of the at least one wavelength that has been phase-modulated.

2. The multi-band optical phased array according to claim 1, characterized in that: Also includes: The phase shift control circuit is arranged on a surface of the substrate away from the array waveguide unit, and is used to drive the array waveguide unit to modulate the phase of an input optical signal of at least one wavelength.

3. The multi-band optical phased array according to claim 1, characterized in that: The waveguide unit comprises: A plurality of phase shifting electrodes and a plurality of waveguide structures; Wherein, a phase shift electrode is provided on both sides of each of the waveguide structures.

4. The multi-band optical phased array according to claim 3, characterized in that: Also includes: A plurality of optical waveguide amplifiers are arranged between the array waveguide unit and the optical antenna, wherein each of the optical waveguide amplifiers is correspondingly connected to an output end of each of the waveguide structures.

5. The multi-band optical phased array according to claim 1, characterized in that: Also includes: A plurality of lasers, each of which is connected to each of the waveguide units in the array waveguide unit, and is used to output an optical signal of the at least one wavelength.

6. The multi-band optical phased array according to claim 4, characterized in that: The optical antenna comprises: A plurality of antenna units, the number of the plurality of antenna units is the same as the number of the output ends of the plurality of waveguide structures, and each of the antenna units is correspondingly connected to the output end of each of the optical waveguide amplifiers.

7. The multi-band optical phased array according to claim 6, characterized in that: Also includes: An optical fiber array, the number of which is the same as the number of the plurality of antenna units, wherein each optical fiber in the optical fiber array connects the output end of each of the optical waveguide amplifiers to each of the antenna units accordingly.

8. The multi-band optical phased array according to claim 7, characterized in that: Also includes: The lens optical fiber is arranged at both ends of each of the optical fibers, one end of which is connected to the output end of the optical waveguide amplifier, and the other end of which is connected to the antenna unit.

9. The multi-band optical phased array according to claim 1, characterized in that: The material of the optical waveguide amplifier includes erbium-doped lithium niobate; the material of the array waveguide unit includes lithium niobate.

10. A method for preparing a multi-band optical phased array, characterized in that: include: bonding a lithium niobate thin film on a substrate; Etching the lithium niobate film to prepare an array waveguide unit; vertically connecting the arrayed waveguide structure to the optical antenna; The array waveguide unit is used to modulate the phase of the input optical signal of at least one wavelength, wherein the number of the array waveguide units is the same as the number of the input optical signal of at least one wavelength, and the optical signal of at least one wavelength is input into the array waveguide unit accordingly; The optical antenna is separated from the substrate and is used to transmit the received optical signal of at least one wavelength which has been phase modulated.

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