Optical signal cache device and optical neural network computing chip

Abstract

The invention relates to the technical field of computing chip cache devices, and discloses an optical signal cache device and an optical neural network computing chip. The optical signal cache device comprises an optical signal delay waveguide; the optical signal delay waveguide comprises a plurality of linear waveguide units and a plurality of spiral waveguide units; the spiral waveguide unit comprises a spiral input section connected with the previous linear waveguide unit in the light input direction and a spiral output section connected with the next linear waveguide unit in the light input direction; the spiral input section and the spiral output section spirally extend to the center of the spiral waveguide unit at the same bending degree and are connected end to end; the spiral waveguide unit further comprises a plurality of mode division multiplexing / demultiplexing devices, the mode division multiplexing / demultiplexing devices stretch across and are connected with the adjacent spiral input sections and spiral output sections, and the mode division multiplexing / demultiplexing devices are connected with different spiral input sections and spiral output sections. According to the invention, the problems of low optical signal caching efficiency, slow response and poor time resolution can be solved.

Description

Technical Field

[0001] The present application relates to the technical field of computing chip cache devices, and in particular to an optical signal cache device and an optical neural network computing chip. Background Art

[0002] With the rapid development of photon counting, photon accelerators based on all-optical processing chips will become an inevitable development trend of optical computing chips. In terms of storage, photon technology has always been difficult to achieve. This is because photons are bosons. Generally speaking, information storage cannot be achieved without converting photons into other forms of energy. The only way out is to delay the optical signal for a period of time to facilitate the processing of high-speed optical signals. Compared with converting optical signals into electrical signals for storage, multi-dimensional information such as phase and polarization in optical signals can be preserved intact, and energy loss and speed limitations in the electro-optical and photoelectric conversion processes can be avoided.

[0003] Photonic computing chips are computing chips that use optical signal caching to solve key problems such as optical signal port contention and packet loss, such as optical neural network computing chips. However, the optical signal caching technology used in optical neural network computing chips has problems such as low efficiency, slow response, and poor time resolution.

[0004] Therefore, a solution is needed to solve the problems of low optical signal caching efficiency, slow response and poor time resolution in optical neural network computing chips. Summary of the invention

[0005] In view of this, the present application provides an optical signal cache device and an optical neural network computing chip to at least solve the problems of low optical signal cache efficiency, slow response and poor time resolution of optical neural network computing chips in related technologies.

[0006] In one aspect of the present application, the present application provides an optical signal buffering device, comprising: an optical signal delay waveguide; the optical signal delay waveguide comprises a plurality of straight waveguide units and a plurality of spiral waveguide units; the spiral waveguide unit comprises a spiral input segment connected to a previous straight waveguide unit in a light input direction and a spiral output segment connected to a subsequent straight waveguide unit in the light input direction; the spiral input segment and the spiral output segment extend spirally to the center of the spiral waveguide unit with the same degree of bending and are connected end to end; the spiral waveguide unit also comprises a plurality of mode division multiplexers / demultiplexers, the mode division multiplexers / demultiplexers spanning and connecting adjacent spiral input segments and spiral output segments, each mode division multiplexer / demultiplexer connecting a different spiral input segment and spiral output segment; each mode division multiplexer / demultiplexer is suitable for being configured to couple different modes of light waves.

[0007] The optical signal buffer device provided by the present application realizes the delay of the light wave by setting a spiral waveguide unit connected to the linear waveguide unit outside the linear waveguide unit; and on the basis of the spiral waveguide unit, a mode division multiplexer / demultiplexer integrated with the linear waveguide unit is set, and different mode division multiplexers / demultiplexers can be configured to couple light waves for different modes, so that light waves of different modes have different propagation paths in the same spiral waveguide unit, and the paths of light waves of different modes are constructed separately, thereby realizing the adjustment of different delays of light waves of different modes, so as to improve the resolution of multi-mode mixed light waves. At the same time, the optical signal buffer device provided by the present application, because the light of some modes changes the path through the mode division multiplexer / demultiplexer, it is equivalent to shortening the travel distance in the waveguide, so compared with a simple spiral waveguide, the total length of time through the spiral waveguide is shortened, so the response to the light wave is faster. In addition, the optical signal buffer device provided by the present application can simultaneously process and respond to multi-mode mixed light waves through a single spiral waveguide unit, greatly improving the optical modulation efficiency. In addition, in the solution of the present application, since a single spiral waveguide unit can adjust light waves of multiple different modes through multiple mode division multiplexers / demultiplexers integrated thereon, there is no need to set up different types of spiral waveguide units for different light waves, thereby saving costs.

[0008] Optionally, in some embodiments, the spiral waveguide unit is a grating type waveguide, and the grating teeth of the grating type waveguide are perpendicular to the spiral extension direction of the grating type waveguide.

[0009] Optionally, in some embodiments, the optical signal delay waveguide includes multiple operation channels; each operation channel includes multiple linear waveguide units located in the same straight line and multiple spiral waveguide units located on the sides of the linear waveguide units; when the optical signal buffer device is a device for image recognition, the number of spiral waveguide units is 2 to 25 per channel; when the optical signal buffer device is a device for matrix operations, the number of spiral waveguide units is 3 to 50.

[0010] Optionally, in some embodiments, the diameter of the spiral waveguide unit is 30 μm to 200 μm; and the spacing between adjacent spiral input segments and spiral output segments is 1.5 μm to 10 μm.

[0011] Optionally, in some embodiments, the curvature radius of the curved arc formed by the spiral input segment of the spiral waveguide unit and the linear waveguide unit connected thereto is 1 μm to 15 μm.

[0012] Optionally, in some embodiments, the connection between the spiral input section and the linear waveguide unit connected thereto is configured as a tapered transition structure in which the width gradually increases from the linear waveguide unit to the spiral input section.

[0013] Optionally, in some embodiments, a mode converter is provided at the connection between the spiral input section and the linear waveguide unit connected thereto, respectively connecting the spiral input section and the linear waveguide unit.

[0014] Optionally, in some embodiments, the optical signal delay waveguide includes a waveguide layer and a substrate layer; the thickness of the waveguide layer is 0.2μm to 3μm; the material of the waveguide layer includes Si, Si3N4, polymethyl methacrylate, polyimide or polycarbonate; the thickness of the substrate layer is 0.5μm to 5μm; the material of the substrate layer includes SiO2, Al2O3, polymethyl methacrylate, polyimide or polycarbonate.

[0015] In another aspect of the present application, the present application also provides an optical neural network computing chip, including the optical signal cache device provided by the present application.

[0016] Optionally, the optical neural network computing chip provided in the present application further includes a temperature control component spaced apart from the optical signal buffer device, suitable for adjusting the temperature of the optical signal buffer device. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 It is a structural schematic diagram of an optical signal buffer device;

[0019] Figure 2 This is a schematic diagram of the structure of an optical signal buffer device according to an embodiment of the present application;

[0020] Figure 3 A schematic diagram of the working state of a mode division multiplexer / demultiplexer in an optical signal buffer device according to an embodiment of the present application;

[0021] Figure 4 A schematic diagram of the working state of another mode division multiplexer / demultiplexer in the optical signal buffer device of an embodiment of the present application;

[0022] Figure 5a and Figure 5b It is a schematic diagram of a local structure of a spiral waveguide unit of different embodiments of the present application being a grating type waveguide;

[0023] Figure 6 It is a schematic longitudinal cross-sectional view of an optical signal buffer device according to an embodiment of the present application.

[0024] The above drawings include the following reference numerals:

[0025] 1-straight waveguide unit; 2-spiral waveguide unit; 21-spiral input section; 22-spiral output section; 23-grating tooth; 3-mode division multiplexer / demultiplexer; L-input light. DETAILED DESCRIPTION

[0026] As mentioned above, the optical signal caching technology used in optical neural network computing chips has problems such as low efficiency, slow response, and poor time resolution. The specific analysis is as follows:

[0027] refer to Figure 1 , which is a schematic diagram of the structure of an optical signal buffer device. The optical signal buffer device includes an optical signal delay waveguide, including multiple linear waveguide units 1 and multiple spiral waveguide units 2. Through the spiral waveguide, the propagation path of the optical signal is increased within a shorter interval (i.e., within the width interval of the spiral waveguide unit 2). Each spiral waveguide unit 2 can delay by one △t. By setting multiple spiral waveguide units on a path, multiple △t delays can be achieved, for example Figure 1 The structure in the figure achieves a delay of 2△t, thereby achieving the caching of optical signals. However, since the structure of the device itself is fixed after the design and production is completed, the delay of the optical signal achieved by the same device is also fixed, so the delay of light waves of different modes in this device is also fixed and the same. For the optical modulation chip where adjacent channels are used to modulate light waves of different modes, the modulation rate f=1 / Δt Baud, Δt is the delay difference between adjacent channels of the optical neural network calculation chip, and there are several such spiral waveguide units in a single channel. Since the structure of a waveguide unit is fixed, the Δt of a single channel can be regarded as the fixed delay of N spiral waveguide units. This Δt cannot be adjusted, so the modulation rate cannot be changed, and multi-mode mixed light cannot be resolved and processed. An additional processing device is required to perform optical wave mode decomposition, and processing is performed through multiple channels, with low resolution. Moreover, the light wave must pass through the total length of all linear waveguide units and spiral waveguide units, and the response time is relatively slow. Therefore, the optical signal cache device has the problems of low cache efficiency, slow response, and poor time resolution. It is impossible to achieve reconfigurable computing for matrix, convolution and other computing scenarios, it is impossible to adjust the chip according to the application scenarios and rate requirements, and it is even more impossible to perform subsequent upgrade operations on the chip.

[0028] The present application provides an optical signal buffer device, comprising: an optical signal delay waveguide; the optical signal delay waveguide comprises a plurality of straight waveguide units and a plurality of spiral waveguide units; the spiral waveguide unit comprises a spiral input section connected to a previous straight waveguide unit in a light input direction and a spiral output section connected to a subsequent straight waveguide unit in the light input direction; the spiral input section and the spiral output section spirally extend to the center of the spiral waveguide unit with the same degree of bending and are connected end to end; the spiral waveguide unit further comprises a plurality of mode division multiplexers / demultiplexers, the mode division multiplexers / demultiplexers spanning and connecting adjacent spiral input sections and spiral output sections, each mode division multiplexer / demultiplexer connecting a different spiral input section and spiral output section; each mode division multiplexer / demultiplexer is suitable for being configured to couple light waves with different modes that are not completely the same.

[0029] The present application also provides an optical neural network computing chip, including the optical signal cache device provided in the present application.

[0030] The technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention. In the description of the present invention, it should be noted that the terms "first", "second" and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0031] Example 1

[0032] refer to Figure 2 This embodiment provides an optical signal buffer device, including:

[0033] Optical signal delay waveguide; the optical signal delay waveguide comprises:

[0034] A plurality of linear waveguide units 1 and a plurality of spiral waveguide units 2;

[0035] The spiral waveguide unit 2 includes a spiral input section 21 connected to the previous linear waveguide unit 1 in the light input direction (input light L in the figure, the direction is shown by the arrow) and a spiral output section 22 connected to the next linear waveguide unit 1 in the light input direction; the spiral input section 21 and the spiral output section 22 extend spirally to the center of the spiral waveguide unit 2 with the same bending degree and are connected end to end; the spiral waveguide unit 2 also includes a plurality of mode division multiplexers / demultiplexers 3, the mode division multiplexers / demultiplexers 3 span and connect adjacent spiral input sections 21 and spiral output sections 22, and each mode division multiplexer / demultiplexer 3 connects a different spiral input section 21 and spiral output section 22. Each of the mode division multiplexers / demultiplexers 3 is suitable for being configured to couple light waves whose modes are not completely the same.

[0036] It should be noted that the marks 21 and 22 in the figure only schematically point to the spiral input section and the spiral output section, and the arrows do not indicate the spiral input section and the spiral output section only. The part from the connecting part of the previous linear waveguide unit 1 to the spiral center of the spiral waveguide unit 2 is the spiral input section 21. Similarly, the part from the spiral center of the spiral waveguide unit 2 to the connecting part of the next linear waveguide unit 1 is the spiral output section 22.

[0037] The optical signal buffer device provided in this embodiment realizes the delay of the light wave by setting a spiral waveguide unit 2 connected to the linear waveguide unit 1 outside the linear waveguide unit 1; and on the basis of the spiral waveguide unit 2, a mode division multiplexer / demultiplexer 3 integrated with the spiral waveguide unit 2 is set, so that the propagation paths of light waves of different modes are different in the same spiral waveguide unit 2, and the paths of light waves of different modes are constructed separately, and then the different delays of light waves of different modes are adjusted, so that the resolution of multi-mode mixed light waves can be improved. At the same time, the optical signal buffer device provided by the present application, because the light of some modes changes the path through the mode division multiplexer / demultiplexer, which is equivalent to shortening the travel distance in the waveguide, the total length of time for this part of the light wave to pass through the spiral waveguide is shortened compared with a simple spiral waveguide, so the response to the light wave is faster. In addition, the optical signal buffer device provided by the present application can simultaneously process and respond to multi-mode mixed light waves through a single spiral waveguide unit, greatly improving the optical modulation efficiency. In addition, in the solution of this embodiment, since a single spiral waveguide unit can adjust light waves of multiple different modes through multiple mode division multiplexers / demultiplexers 3 integrated thereon, there is no need to set different types of spiral waveguide units 2 for different light waves, thereby saving costs.

[0038] Specifically, refer to Figure 3 and Figure 4 , the working principle of the optical signal buffer device of this embodiment is further explained. The figure shows a pair of adjacent spiral input sections 21 and spiral output sections 22. Figure 3 As shown, the input light L includes optical signals of modes TE0, TE1, and TE2. Due to the presence of the mode division multiplexer / demultiplexer, when the input light is transmitted to the first mode division multiplexer / demultiplexer 3, the mode division multiplexer / demultiplexer 3 is configured to couple only TE1 and TE2, so the TE0 light is not coupled, and the TE0 light continues to propagate along the original path of the spiral input section 21; Figure 4 As shown, when the mode of the input light L is TE1, when the input light is transmitted to the first mode division multiplexer / demultiplexer 3, the optical signal will be coupled into the mode division multiplexer / demultiplexer 3, and then enter the adjacent spiral output section 22. Therefore, Figure 3 TE0 light and Figure 4 The propagation path of TE1 light in the image is differentiated. Figure 3The delay of TE0 light in is △t1, Figure 4 The delay of TE1 light is △t2. Since TE1 light has less spiral input section and spiral output section than TE0 light, △t2<△t1. Similarly, when the mode of input light L is TE2, it can be coupled by another mode division multiplexer / demultiplexer 3 at another position and enter the adjacent spiral output section 22. In this way, the propagation paths of TE1 light and TE2 light are differentiated again. The delay of TE1 light is △t2, and the delay of TE1 light is △t3. Since TE2 light has less spiral input section and spiral output section than TE1 light, △t3<△t2. In this way, by placing multiple mode division multiplexers / demultiplexers 3 at different positions, the optical paths of input lights of multiple modes can be reconstructed in one spiral waveguide unit, so that lights of different modes exhibit different delays. In addition, the setting of multiple spiral waveguide units makes this path difference superimposed and amplified. The delay of a single spiral waveguide unit is △t, and N spiral waveguide units are superimposed as N×△t, so that the difference in optical delay of different modes can be more obvious, which can improve the time resolution of optical signals. Since the path of the light wave of some modes has changed, it is not necessary to completely go through the path of all spiral waveguide units, that is, the propagation path is shortened, so the time to pass through the entire channel is also reduced, so the response speed of the device is faster. In addition, a single spiral waveguide unit can directly modulate multi-mode mixed light waves without the need for additional configuration of devices for pre-mode division, which greatly improves the light modulation efficiency. In addition, the mode of the light that the mode multiplexer / demultiplexer is suitable for coupling can be adjusted as needed, so the path of light of different modes passing through the spiral waveguide unit can be adjusted as needed, that is, △t can be adjusted, thereby realizing the adjustment of the light modulation rate of different modes at the chip level, and reconfigurable computing can be realized. By simply converting the input light mode, the delay of the optical cache device can be flexibly controlled. There are dozens of available eigenmodes in the communication band, so it is very suitable for reconfigurable optical computing chips. The chip can also be calibrated to improve computing power and accuracy.

[0039] Further, in some embodiments, the spiral waveguide unit is a grating waveguide, and the grating teeth of the grating waveguide are perpendicular to the spiral extension direction of the grating waveguide. Figure 5a and Figure 5b , the spiral input section 21 or the spiral output section 22 extends along the spiral direction (the figure is a perspective perpendicular to the spiral extension direction, so the spiral input section 21 or the spiral output section 22 is shown as a straight extension), and the grating teeth 23 of the grating waveguide are perpendicular to the spiral extension direction. Since the spiral waveguide unit is a grating waveguide, the time for light to pass through is increased compared to the ordinary waveguide structure, so that the total time for light waves to pass through in a single channel is increased, and the △t between light waves of different modes is more obvious, thereby improving the light wave resolution of the optical signal buffer device. The grating waveguide can be configured as Figure 5aThe common waveguide structure and the grating teeth 23 can also be combined in the form of Figure 5b The form of a simple grating tooth 23.

[0040] In addition, it should be noted that Figure 2 , Figure 3 , Figure 4 This is a top view of the device (not true to scale), but Figure 5a , Figure 5b It is not a view from the top of the device, but a view from the spiral surface of the spiral waveguide unit in a direction perpendicular to the spiral surface of the spiral waveguide unit. Figure 5a , Figure 5b The middle spiral input section 21 or the spiral output section 22 is shown as extending in a straight line.

[0041] Further, in some embodiments, the optical signal delay waveguide includes multiple operation channels; each operation channel includes multiple linear waveguide units 1 located in the same straight line and multiple spiral waveguide units 2 located on the side of the linear waveguide unit 1; when the optical signal buffer device is a device for image recognition, the number of spiral waveguide units 2 is 2 to 25 per channel; when the optical signal buffer device is a device for matrix operation, the number of spiral waveguide units is 3 to 50. The number of optical buffer units used can be determined according to the changes in the application scenario.

[0042] Furthermore, in some embodiments, the diameter of the spiral waveguide unit 2 is 30μm to 200μm; the spacing between adjacent spiral input segments and spiral output segments is 1.5μm to 10μm. If the diameter is too large, the corresponding device volume will increase, and when applied to a chip, the chip area will also need to be increased accordingly, affecting the miniaturization of the device size; if the diameter is too small, the corresponding delay time will be too short, and the resolution improvement will not be obvious. Therefore, the diameter of the spiral waveguide unit 2 is within the range of 30μm to 200μm, which can strike a balance between effectively improving the resolution and avoiding hindering the miniaturization of the chip. In this way, the optical signal delay time of each spiral waveguide unit 2 can reach 5ps to 300ps, and the corresponding chip computing speed, that is, the optical modulation rate can reach 5Gbaud to 200Gbaud.

[0043] Furthermore, in some embodiments, the curvature radius r of the curved arc formed by the spiral input section of the spiral waveguide unit 2 and the linear waveguide unit connected thereto is 1 μm to 15 μm. If the curvature radius is too large, the chip area utilization rate is too low, and the chip size needs to be increased accordingly, which greatly affects the chip miniaturization; if the curvature radius is too small, coupling is likely to occur between adjacent spiral input sections and spiral output sections, resulting in a deviation between the optical modulation and the expected effect. The typical loss value of a 90-degree curved waveguide is 0.01 dB / bend, indicating that the chip area occupied by the device of the present invention can be very small and compact, and has the advantages of low cost and multiple functions. For optical computing chips that are sensitive to device loss, the curvature radius r can be appropriately increased. Increasing the curvature radius can reduce the curvature, making the propagation of light closer to its natural straight path, thereby reducing the radiation loss during the propagation of optical information.

[0044] Furthermore, in some embodiments, the connection between the spiral input section 21 and the linear waveguide unit 1 connected thereto is configured as a tapered transition structure (not shown in the figure) with a width gradually increasing from the linear waveguide unit 1 to the spiral input section 21. By configuring the connection as a tapered transition structure with a width gradually increasing, the optical signal can be gradually transitioned from the linear waveguide unit 1 to the spiral input section 21 instead of entering in a leapfrog manner, thereby reducing the mode mismatch in the waveguide conversion stage.

[0045] Furthermore, in some embodiments, a mode converter (not shown in the figure) is provided at the connection between the spiral input section and the linear waveguide unit connected thereto, respectively connecting the spiral input section and the linear waveguide unit. By providing the mode converter, the optical signal can be gradually transferred from the linear waveguide unit 1 to the spiral input section 21, rather than entering in a leapfrog manner, thereby reducing the mode mismatch in the waveguide conversion stage.

[0046] For further reference, Figure 6 In some embodiments, the optical signal delay waveguide includes a waveguide layer and a substrate layer; the thickness Hc of the waveguide layer is 0.2 μm to 3 μm; the material of the waveguide layer includes Si, Si3N4, polymethyl methacrylate, polyimide or polycarbonate; the thickness Hsi of the substrate layer is 0.5 μm to 5 μm; the material of the substrate layer includes SiO2, Al2O3, polymethyl methacrylate, polyimide or polycarbonate.

[0047] Example 2

[0048] In another aspect of the present application, the present application also provides an optical neural network computing chip, including the optical signal cache device provided in the above-mentioned embodiment 1.

[0049] The optical neural network computing chip provided in this embodiment includes the optical signal buffer device provided in the above-mentioned embodiment 1, and the delay of the light wave is realized by setting a spiral waveguide unit 2 connected to the linear waveguide unit 1 outside the linear waveguide unit 1; and on the basis of the spiral waveguide unit 2, a mode division multiplexer / demultiplexer 3 integrated therewith is set, so that light waves of different modes have different propagation paths in the same spiral waveguide unit 2, and the paths of light waves of different modes are constructed separately, thereby realizing the adjustment of different delays of light waves of different modes, thereby solving the problems of low efficiency, slow response and poor time resolution of the optical signal buffer of the optical neural network computing chip. In addition, in the scheme of this embodiment, since a single spiral waveguide unit can realize the adjustment of light waves of multiple different modes through multiple mode division multiplexers / demultiplexers 3 integrated thereon, it is not necessary to set different types of spiral waveguide units 2 for different light waves, thereby saving costs.

[0050] In some embodiments, the optical neural network computing chip provided in the present application further includes a temperature control component spaced apart from the optical signal buffer device, suitable for adjusting the temperature of the optical signal buffer device.

[0051] By setting up a temperature control component for the cache device in the chip, the temperature of the cache device can be regulated, thereby changing the light propagation rate in the cache device, so that the required modulation accuracy can be adjusted as needed, thereby improving the computing power upper limit of the computing chip, and being able to calibrate the optical path under a certain baud rate condition to achieve high-precision optical computing.

[0052] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. An optical signal buffer device, characterized in that: include: Optical signal delay waveguide; The optical signal delay waveguide includes a plurality of straight waveguide units and a plurality of spiral waveguide units; The spiral waveguide unit comprises a spiral input section connected to a previous linear waveguide unit in the light input direction and a spiral output section connected to a subsequent linear waveguide unit in the light input direction; The spiral input section and the spiral output section spirally extend to the center of the spiral waveguide unit with the same bending degree and are connected end to end; The spiral waveguide unit further comprises a plurality of mode division multiplexers / demultiplexers, wherein the mode division multiplexers / demultiplexers span and connect adjacent spiral input segments and spiral output segments, and each of the mode division multiplexers / demultiplexers connects different spiral input segments and spiral output segments; Each of the mode division multiplexers / demultiplexers is adapted to be configured to couple light waves whose modes are not completely the same.

2. The optical signal buffer device according to claim 1, characterized in that: The spiral waveguide unit is a grating waveguide, and the grating teeth of the grating waveguide are perpendicular to the spiral extension direction of the grating waveguide.

3. The optical signal buffer device according to claim 1, characterized in that: The optical signal delay waveguide includes a plurality of operation channels; Each of the operation channels includes a plurality of the linear waveguide units located on the same straight line and a plurality of the spiral waveguide units located on the side of the linear waveguide unit; When the optical signal buffer device is a device for image recognition, the number of the spiral waveguide units is 2 to 25 per channel; When the optical signal buffer device is a device for matrix operation, the number of the spiral waveguide units is 3 to 50.

4. The optical signal buffer device according to claim 1, characterized in that: The diameter of the spiral waveguide unit is 30 μm to 200 μm; The distance between adjacent spiral input sections and spiral output sections is 1.5 μm to 10 μm.

5. The optical signal buffer device according to claim 1, characterized in that: The curvature radius of the curved arc formed by the spiral input section of the spiral waveguide unit and the linear waveguide unit connected thereto is 1 μm to 15 μm.

6. The optical signal buffer device according to claim 1, characterized in that: The connection between the spiral input section and the linear waveguide unit connected thereto is arranged as a tapered transition structure with a width gradually increasing from the linear waveguide unit to the spiral input section.

7. The optical signal buffer device according to claim 1, characterized in that: A mode converter is provided at the connection between the spiral input section and the linear waveguide unit connected thereto, and is respectively connected to the spiral input section and the linear waveguide unit.

8. The optical signal buffer device according to claim 1, characterized in that: The optical signal delay waveguide comprises a waveguide layer and a substrate layer; The thickness of the waveguide layer is 0.2 μm to 3 μm; the material of the waveguide layer includes Si, Si3N4, polymethyl methacrylate, polyimide or polycarbonate; The thickness of the base layer is 0.5 μm to 5 μm; the material of the base layer includes SiO2, Al2O3, polymethyl methacrylate, polyimide or polycarbonate.

9. An optical neural network computing chip, characterized in that: The optical signal buffer device comprises the optical signal buffer device according to any one of claims 1 to 8.

10. The optical neural network computing chip according to claim 9, characterized in that: Also includes: A temperature control component is arranged at a distance from the optical signal buffer device, and the temperature control component is suitable for adjusting the temperature of the optical signal buffer device.

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