CN115494912B

CN115494912B - Optical chip, parameter determination method and operation equipment for realizing multi-order differential operation

Info

Publication number: CN115494912B
Application number: CN202211444220.4A
Authority: CN
Inventors: 刘洋; 张斗国
Original assignee: University of Science and Technology of China USTC
Current assignee: University of Science and Technology of China USTC
Priority date: 2022-11-18
Filing date: 2022-11-18
Publication date: 2023-03-10
Anticipated expiration: 2042-11-18
Also published as: CN115494912A

Abstract

The invention provides an optical chip, a parameter determination method and operation equipment for realizing multi-order differential operation. The optical chip for realizing multi-order differential operation comprises: a glass substrate; set up the photonic crystal film structure on the glass substrate, the photonic crystal film structure includes: the light transmittance modulation film includes a first transmittance film and a second transmittance film. The thickness and the refractive index of the optical chip are changed, so that the transmissivity of incident light which enters the optical chip from different angles is changed, the incident light is transmitted and modulated, and first-order differential operation, second-order differential operation, third-order differential operation and fourth-order differential operation of light field information included by the incident light are achieved. The invention is applied to the field of optical simulation calculation.

Description

Optical chip, parameter determination method and operation equipment for realizing multi-order differential operation

Technical Field

The invention relates to the field of optical simulation calculation, in particular to an optical chip, a parameter determination method and operation equipment for realizing multi-order differential operation.

Background

Optical simulation calculation is a method for performing simulation calculation on light field information by using an optical means, with the development of related technologies, the demand for large-scale real-time data processing is rapidly increased, optical simulation calculation is widely concerned, and the continuous development of nanophotonics also brings new opportunities to the field of optical simulation calculation. In the related analog computing technology, a digital signal processing mode can realize various signal processing functions, but due to the limitation of the process level, the processing speed of the digital signal processing mode is low, and the power consumption is high, so that the digital signal processing cannot meet the computing requirements. And the optical signal has the characteristics of high transmission speed and low power consumption relative to the electric signal, so that the optical analog calculation is more efficient when solving part of specific problems. The volume of the optical element and system for the related optical simulation calculation is gradually developed from large volume to miniaturization and integration along with the development of nano photonics and the application of super surface and super material. The optical differential operator belongs to one kind of optical analog computation equipment, can carry out differential operation to a plurality of light field calculation light paths in parallel, and optical analog computation has more important application prospect in technical fields such as edge detection, computer vision, biological imaging and autopilot. However, in the related art, the structure of the optical differential operator can only support performing one differential operation, and a complicated surface structure is required to implement the differential operation, which makes the functions of these optical differential operators insufficient to solve the actual demands and cannot be prepared on a large scale.

Disclosure of Invention

In view of the above, the present invention provides an optical chip, a parameter determining method and an arithmetic device for implementing multi-order differential operation, so as to partially solve at least one of the above-mentioned technical problems.

In one aspect of the invention, an optical chip for implementing multi-order differential operations is provided.

The optical chip for realizing the multi-order differential operation comprises:

a glass substrate; set up the photonic crystal film structure on above-mentioned glass substrate, above-mentioned photonic crystal film structure includes: the light-emitting device includes a transmittance modulation film including a first transmittance film and a second transmittance film.

Alternatively, the optical chip for implementing the multi-order differential operation is configured to:

under the condition that the first radial angle and the first azimuth angle meet a first preset condition, first-order differential operation is carried out on incident light with a first wavelength through the optical chip; performing a second order differential operation on the first wavelength incident light by the optical chip when the first radial angle and the first azimuthal angle satisfy a second predetermined condition, wherein the first radial angle is an angle between the first wavelength incident light and a normal of a plane on which a surface of the photonic crystal film structure on which the first wavelength incident light is incident is located; the first azimuth angle is a complementary angle of an included angle between a straight line where a projection of the first wavelength incident light in the plane is located and a straight line where a polarization direction of the projection of the first wavelength incident light in the plane is located.

Alternatively, the optical chip for implementing the multiple-order differential operation is configured to:

under the condition that the second radial angle and the second azimuth angle meet a third preset condition, the incident light with the second wavelength performs third-order differential operation through the optical chip; performing a fourth order differential operation on the second wavelength incident light through the optical chip when the second radial angle and the second azimuth angle satisfy a fourth preset condition, wherein the second radial angle is an included angle between the second wavelength incident light and a normal of a plane on which a surface of the photonic crystal film structure on which the second wavelength incident light is incident is located; the second azimuth angle is a complementary angle of an included angle between a straight line of a projection of the second wavelength incident light in the plane and a straight line of a polarization direction of the projection of the second wavelength incident light in the plane.

Alternatively, the basic transmittance of the optical chip for performing the multi-step differential operation is obtained based on the refractive index of the glass substrate, the refractive index of the first transmittance film, and the refractive index of the second transmittance film; the first order differential operation, the second order differential operation, the third order differential operation, and the fourth order differential operation are realized by transmission-modulating the first wavelength incident light and the second wavelength incident light based on the optical chip configured to have the basic transmittance.

Alternatively, in the photonic crystal film structure connected to the glass substrate, one surface of the first transmittance film is in contact with the glass substrate, and the other surface is in contact with the second transmittance film.

Alternatively, the refractive index of the first transmittance film is greater than the refractive index of the second transmittance film and the refractive index of the glass substrate, and the refractive index of the second transmittance film is not equal to the refractive index of the glass substrate.

In another aspect of the present invention, a method for determining parameters of an optical chip implementing multi-order differential operations is provided.

The parameter determination method of the optical chip for realizing the multi-order differential operation comprises the following steps:

determining a target transmittance of the optical chip according to a first wavelength incident light, a second wavelength incident light, a fitted transmittance curve corresponding to a differential operation of the first wavelength incident light, and a fitted transmittance curve corresponding to a differential operation of the second wavelength incident light; determining the structural parameters of a target optical chip by a transfer matrix theory according to the target transmissivity so as to prepare the optical chip; wherein, the target optical chip structure parameters include: the optical chip structure parameters comprise: a target third thickness of the glass substrate of the optical chip and a target third refractive index of the glass substrate; a target first thickness of a first transmittance film of a transmittance modulation film of a photonic crystal film structure disposed on the glass substrate of the optical chip, a target first refractive index of the first transmittance film, a target second thickness of a second transmittance film of a transmittance modulation film of a photonic crystal film structure disposed on the glass substrate of the optical chip, and a target second refractive index of the second transmittance film.

Alternatively, the determining the target transmittance of the optical chip according to the first wavelength incident light, the second wavelength incident light, the fitted transmittance curve corresponding to the differential operation of the first wavelength incident light, and the fitted transmittance curve corresponding to the differential operation of the second wavelength incident light includes:

determining a first target emergent polarization state after the first wavelength incident light is emergent from the optical chip according to a wavelength parameter of the first wavelength incident light, a first incident polarization state before the first wavelength incident light is incident on the optical chip, a first fitted transmittance curve of the first wavelength incident light when first-order differential operation is performed, and a second fitted transmittance curve of the first wavelength incident light when second-order differential operation is performed; determining a second target emergent polarization state after the second wavelength incident light is emergent from the optical chip according to the wavelength parameter of the second wavelength incident light, a second incident polarization state before the second wavelength incident light is incident on the optical chip, a third fitted transmittance curve when the second wavelength incident light is subjected to third-order differential operation, and a fourth fitted transmittance curve when the second wavelength incident light is subjected to fourth-order differential operation; the target transmittance of the optical chip is determined based on the wavelength parameter of the first wavelength incident light, the first incident polarization state, the first fitted transmittance curve, the second fitted transmittance curve, the first target outgoing polarization state, the wavelength parameter of the second wavelength incident light, the second incident polarization state, the third fitted transmittance curve, the fourth fitted transmittance curve, and the second target outgoing polarization state.

Alternatively, the determining the target optical chip structure parameters according to the target transmittance by the transfer matrix theory includes:

the first thickness of the first transmittance film, the first refractive index of the first transmittance film, the second thickness of the second transmittance film, the second refractive index of the second transmittance film, the third thickness of the glass substrate, and the third refractive index of the glass substrate are determined so as to obtain the transmittance of the optical chip by the transfer matrix theory, and the target first thickness, the target first refractive index, the target second thickness, the target second refractive index, the target third thickness, and the target third refractive index are determined when the difference between the obtained transmittance of the optical chip and the target transmittance is the minimum. In still another aspect of the present invention, there is provided a multi-order differential operation apparatus based on an optical chip that implements a multi-order differential operation.

The multiple order differential operation device includes: the device comprises an acquisition module, an incident light angle adjusting module, a modulation module, an operation module and a polarization state adjusting module.

The acquisition module is used for acquiring incident light with a first wavelength and incident light with a second wavelength; the incident light angle adjusting module is used for adjusting the angles of the first wavelength incident light and the second wavelength incident light to obtain adjusted first wavelength incident light and adjusted second wavelength incident light; a modulation module, configured to modulate information that requires the multi-order differential operation onto the adjusted first wavelength incident light and the adjusted second wavelength incident light to obtain first modulated light corresponding to the adjusted first wavelength incident light and second modulated light corresponding to the adjusted second wavelength incident light; an operation module, configured to perform the multi-order differential operation on the first modulated light and the second modulated light to obtain first outgoing light and second outgoing light that include results of the multi-order differential operation, where the operation module includes the optical chip that implements the multi-order differential operation; and a polarization state adjusting module for adjusting the polarization states of the first wavelength incident light and the second wavelength incident light, and for adjusting the polarization states of the first emergent light and the second emergent light.

Based on the technical scheme, compared with the prior art, the embodiment of the invention has the following beneficial effects:

the incident light is subjected to transmission modulation based on the optical chip, and different transmission modulation is performed on the incident light by changing the thickness and refractive index parameters of a glass substrate, a first transmittance film and a second transmittance film which are included in the optical chip, so that the incident light is modulated to realize first-order differential operation, second-order differential operation, third-order differential operation and fourth-order differential operation. Compared with differential operation performed by an electronic differential operation method, the optical chip performs photon operation according to light field information, and the differential operation technology realized based on the optical chip has the characteristics of high processing speed and low power consumption because the light propagation speed is far higher than the electron propagation speed and the heat loss of light propagation is far less than the heat loss of electron propagation. Compared with an optical differential operation method which can only perform single differential operation in the related technology, the optical chip-based optical differential operation method can simultaneously perform first-order differential operation, second-order differential operation, third-order differential operation and fourth-order differential operation, and is wider in application. The optical chip is multi-order differential operation realized by utilizing the modulation of the multilayer film structure, and the optical chip does not need to occupy a large amount of space, so that the miniaturization of an operation device can be realized; and the multilayer film structure has no surface microstructure, so the preparation process is simple and the quantitative production is convenient.

Drawings

FIG. 1 is a schematic diagram of an optical chip according to an embodiment of the present invention.

FIG. 2a shows a schematic diagram of a calculated transmittance curve and a fitted transmittance curve of a first order differential operation according to an embodiment of the present invention.

FIG. 2b shows a schematic diagram of a calculated transmittance curve and a fitted transmittance curve of a second order differential operation according to an embodiment of the present invention.

FIG. 2c shows a schematic diagram of a calculated transmittance curve and a fitted transmittance curve of a third order differential operation according to an embodiment of the present invention.

FIG. 2d shows a graph of calculated transmittance curves and fitted transmittance curves for a fourth order differential operation according to an embodiment of the present invention.

Fig. 3 shows a flow chart of a parameter determination method according to an embodiment of the invention.

FIG. 4 is a diagram illustrating a structure of a multi-order differential operation apparatus according to an embodiment of the present invention.

FIG. 5 is a schematic diagram of a multi-order differential operation apparatus according to another embodiment of the present invention.

Fig. 6 shows a graph of experimental results of a light field of amplitude information in a USAF standard resolution target according to an embodiment of the present invention.

Fig. 7a is a graph showing the experimental results of a processed image after a first order differential operation of the optical field of amplitude information in the USAF standard resolution target according to an embodiment of the present invention.

FIG. 7b illustrates a corresponding edge strength cross-sectional view of FIG. 7a, in accordance with an embodiment of the present invention.

Fig. 7c shows a graph of experimental results of processed images after a second order differential operation of the optical field of amplitude information in the USAF standard resolution target according to an embodiment of the present invention.

FIG. 7d shows a corresponding edge strength cross-sectional view of FIG. 7c, in accordance with an embodiment of the present invention.

Fig. 7e shows a graph of experimental results of processed images after a third order differential operation of the optical field of amplitude information in the USAF standard resolution target according to an embodiment of the present invention.

FIG. 7f illustrates a corresponding edge strength cross-sectional view of FIG. 7e, in accordance with embodiments of the present invention.

Fig. 7g is a graph showing the experimental results of the processed image after the fourth order differential operation of the optical field of amplitude information in the USAF standard resolution target according to an embodiment of the present invention.

FIG. 7h illustrates a corresponding edge strength cross-sectional view of FIG. 7g, in accordance with an embodiment of the present invention.

Detailed Description

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. It is to be understood that such description is merely illustrative and not intended to limit the scope of the present invention. In the following detailed description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the embodiments of the invention. It may be evident, however, that one or more embodiments may be practiced without these specific details. Moreover, in the following description, descriptions of well-known structures and techniques are omitted so as to not unnecessarily obscure the concepts of the present invention.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The terms "comprises," "comprising," and the like, as used herein, specify the presence of stated features, steps, operations, and/or components, but do not preclude the presence or addition of one or more other features, steps, operations, or components.

All terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs, unless otherwise defined. It is noted that the terms used herein should be interpreted as having a meaning that is consistent with the context of this specification and should not be interpreted in an idealized or overly formal sense.

Where a convention analogous to "at least one of A, B and C, etc." is used, in general such a construction should be interpreted in the sense one having ordinary skill in the art would understand the convention (e.g., "a system having at least one of A, B and C" would include but not be limited to systems that have a alone, B alone, C alone, a and B, a and C, B and C, and/or A, B, C, etc.).

In implementing the concept of the present invention, the inventors found that at least the following problems exist in the related art:

the optical differential operator can perform differential operation on a plurality of optical field calculation optical paths in parallel, but in the related art, the optical differential operator generally performs modulation on the plurality of optical field optical paths by manufacturing a complicated surface structure on a surface on which the differential operator performs differential operation, thereby performing differential operation. The complex surface structure limits that the optical differential operator can only perform fixed differential operation, and the complex surface structure causes that the large-scale preparation of the optical differential operator is limited, so that the function of the optical differential operator is not enough to solve the actual requirement.

Therefore, an optical chip that can implement multi-order differential operation and is simple to manufacture is needed.

In order to at least partially solve the technical problems in the related art, the present invention provides an optical chip, a parameter determining method, and an arithmetic device for implementing a multiple-order differential operation. The method can be applied to the field of optical simulation calculation.

According to an embodiment of the present invention, an optical chip for implementing multi-order differential operations is provided.

The optical chip for realizing multi-order differential operation comprises:

a glass substrate; set up the photonic crystal film structure on the glass substrate, the photonic crystal film structure includes: the light transmittance adjusting film may include a plurality of layers, wherein one layer may include a first transmittance film and a second transmittance film.

As shown in fig. 1, an optical chip 8 for implementing multi-order differential operation includes a glass substrate 1, and a photonic crystal film structure 2 disposed on the glass substrate 1. The photonic crystal film structure 2 includes: the transmittance modulation films 13 include a predetermined number of layers, and the transmittance modulation films 13 include a first transmittance film 3 and a second transmittance film 4.

According to the embodiment of the present invention, in the case that the optical chip 8 implements the multi-order differential operation of the light field information included in the incident light, it may be configured to construct a three-dimensional rectangular coordinate system with reference to the optical chip 8 and the incident light, so as to describe a process of implementing the multi-order differential operation by the optical chip 8. As shown in fig. 1, incident light a may be set to enter the optical chip 8 through the surface of the photonic crystal film structure 2, where the incident light a is set to be incident light including preset polarization state optical field information, and a polarization propagation direction of the incident light a projected on the plane of the surface of the photonic crystal film structure 2 is an x direction in the plane under the condition that the incident light a is projected on the plane of the surface of the photonic crystal film structure 2; taking the x direction as a reference, and taking the direction after rotating by 90 degrees counterclockwise in the plane as the y direction in the plane; with reference to the y-direction, the direction rotated 90 ° counterclockwise out of the plane is the z-direction perpendicular to the plane and away from the plane.

According to the embodiment of the invention, an included angle between a straight line of the incident light A and the z direction is set as a radial angle, and the projection of the incident light A in the plane of the surface of the photonic crystal film structure 2 is a first projection. As shown in fig. 1, an included angle between a straight line where the first projection is located and the y direction may be set as an azimuth, a projection of the first projection in the y direction may be set as a second projection, and a projection of the first projection in the x direction may also be set as a third projection.

According to the embodiment of the invention, the incident light A is set to be the incident light including the information of the optical field in the preset polarization state, and by adjusting the preset polarization state, before the incident light A is incident on the optical chip 8 through the surface of the photonic crystal film structure 2, that is, in the space outside the optical chip 8, the preset polarization state can be represented by the polarization component in the z direction and the polarization component in the x direction, and meanwhile, the polarization component does not exist in the y direction.

According to the embodiment of the present invention, the predetermined number of the transmittance modulation films 13 may be disposed on the glass substrate 1 such that the predetermined number of the first transmittance films 3 and the predetermined number of the second transmittance films 4 are overlapped on the glass substrate 1. After the incident light a is incident to the optical chip 8 through the surface of the photonic crystal film structure 2, the transmittance of the incident light a in the optical chip 8 is modulated by the thickness and refractive index parameters of the first and

second transmittance films

3 and 4 and the thickness and refractive index parameters of the glass substrate 1. By adjusting the thickness and refractive index parameters of the first and

second transmittance films

3 and 4, the transmittance of the incident light a satisfies a predetermined condition under the condition that the incident light a is modulated, and the incident light a is modulated to realize first order differential operation, second order differential operation, third order differential operation, and fourth order differential operation.

According to the embodiment of the invention, after the incident light A is modulated by the transmission of the optical chip 8, the modulation of the preset polarization state of the incident light A can be realized, and the emergent light B is obtained. In the case where the incident light a is not incident on the optical chip 8, the preset polarization state of the incident light a may include a polarization component in the z direction and a polarization component in the x direction and not include a polarization component in the y direction. The incident light A is input into the optical chip 8 for transmission modulation, so that the polarization state of the emergent light B can comprise a polarization component in the opposite direction of the z direction, a polarization component in the y direction and a polarization component in the x direction under the condition that the emergent light B exits to the outside of the optical chip 8.

According to the embodiment of the invention, the incident light A is subjected to transmission modulation based on the optical chip 8, and different transmission modulation is carried out on the incident light A by changing the thickness and refractive index parameters of the glass substrate 1, the first transmittance film 3 and the second transmittance film 4 which are included in the optical chip 8, so that the incident light A is modulated to realize first-order differential operation, second-order differential operation, third-order differential operation and fourth-order differential operation. Compared with differential operation performed by an electronic differential operation method, the optical chip 8 performs photon operation according to light field information, and the differential operation technology implemented based on the optical chip 8 has the characteristics of high processing speed and low power consumption because the light propagation speed is much higher than the electron propagation speed and the heat loss of light propagation is much smaller than the heat loss of electron propagation. Compared with the optical differential operation method which only can perform single differential operation in the related technology, the optical chip 8 based optical differential operation method can simultaneously perform first-order differential operation, second-order differential operation, third-order differential operation and fourth-order differential operation, and is wider in application. The optical chip 8 is a multi-order differential operation realized by utilizing the modulation of a multi-layer film structure, and the optical chip 8 does not need to occupy a large amount of space per se, so that the miniaturization of an operation device can be realized; and the multilayer film structure has no surface microstructure, so the preparation process is simple and the quantitative production is convenient.

According to the embodiment of the present invention, the base transmittance of the optical chip 8 is obtained from the refractive index of the glass substrate, the refractive index of the first transmittance film, and the refractive index of the second transmittance film. Based on the optical chip configured as the basic transmittance, the transmission modulation is performed on the first wavelength incident light and the second wavelength incident light, and the first order differential operation, the second order differential operation, the third order differential operation and the fourth order differential operation are realized.

According to the embodiment of the present invention, the base transmittance is set to a transmittance that can be obtained only according to the thickness of the glass substrate 1, the refractive index of the glass substrate 1, the thickness of the preset number of layers of the first transmittance films 3, the refractive index of the preset number of layers of the first transmittance films 3, the thickness of the preset number of layers of the second transmittance films 4, and the refractive index of the preset number of layers of the second transmittance films 4 in the case where no incident light is incident on the optical chip 8. By varying the specific values of the thickness and refractive index mentioned above, the base transmittance of the optical chip 8 can be varied.

According to the embodiment of the invention, under the condition that the incident light enters the optical chip 8, the basic transmittance of the optical chip 8 is different in modulation of different incident lights according to the difference of the incident radial angle and the incident azimuth angle of the incident light, so that different modulation is realized on different incident lights. The final modulation effect to be obtained can be set first, and the modulation effect on different incident lights can be changed by changing the basic transmittance of the optical chip 8, so that the structural parameters of the optical chip 8 according with the required final modulation effect can be obtained finally.

According to the embodiment of the present invention, in the case where the refractive index of the first transmittance film 3 is greater than the refractive index of the second transmittance film 4 and the refractive index of the glass substrate 1, respectively, and the refractive index of the second transmittance film 4 and the refractive index of the glass substrate 1 are equal, in the photonic crystal film structure 2 connected to the glass substrate 1, one surface of the first transmittance film 3 contacts the glass substrate 1, and the other surface of the first transmittance film 3 contacts the second transmittance film 4.

According to the embodiment of the present invention, it can be understood that, in the case where the refractive index of the second transmittance film 4 is equal to the refractive index of the glass substrate 1, if the second transmittance film 4 contacts the glass substrate 1 in the photonic crystal film structure 2 connected to the glass substrate 1, a layer of the second transmittance film 4 equivalent to the contact of the glass substrate 1 with the glass substrate 1 together constitutes a new layer of the glass substrate 1, or it can be considered that the thickness of the layer of the second transmittance film 4 contacting the glass substrate 1 is changed, and further, the structural parameters of the optical chip 8 are changed, resulting in that the modulation of the incident light by the optical chip 8 is changed, and thus, it may result in that the first order differential operation, the second order differential operation, the third order differential operation, or the fourth order differential operation on the incident light cannot be realized. Therefore, in the case where the refractive index of the first transmittance film 3 is greater than the refractive index of the second transmittance film 4 and the refractive index of the glass substrate 1, and the refractive index of the second transmittance film 4 and the refractive index of the glass substrate 1 are equal, the glass substrate 1 and the second transmittance film 4 do not contact.

According to the embodiment of the present invention, it can be understood that the predetermined number of first transmittance films 3 included in the photonic crystal film structure 2 are not in contact with each other, and the predetermined number of second transmittance films 4 are also not in contact with each other.

According to the embodiment of the present invention, in the case where the refractive index of the first refractive index film 3 is greater than the refractive index of the second transmissive film 4 and the refractive index of the glass substrate 1, and the refractive index of the second transmissive film 4 and the refractive index of the glass substrate 1 are not equal, the kind of the transmissive film with which the glass substrate 1 is in contact is not limited.

According to the embodiment of the present invention, it is understood that in the case where the refractive indexes of the glass substrate 1, the first transmittance film 3, and the second transmittance film 4 are not equal, the case where the films are merged with each other does not occur, and it is not necessary to limit the kind of the transmittance film contacting the glass substrate 1.

According to the embodiment of the present invention, the wave vector of the incident light a in the space is k0, the wave vector of the first projection of the incident light a in the plane of the surface of the photonic crystal film structure 2 is kr, the wave vector of the second projection of the wave vector of the first projection in the y direction is ky, and the wave vector of the third projection of the wave vector of the first projection in the x direction is kx.

According to an embodiment of the present invention, the incident light a may include a first wavelength incident light and a second wavelength incident light. Wherein the first order differential operation and the second order differential operation can be performed by the first wavelength incident light; and the third-order differential operation and the fourth-order differential operation are completed by the incident light with the second wavelength.

According to an embodiment of the invention, the optical chip 8 may be configured to: at a first radial angle

And a first azimuth angle

And under the condition of meeting a first preset condition, the first-order differential operation is carried out on the first-wavelength incident light through the optical chip. At a first radial angle

And a first azimuth angle

And under the condition of meeting a second preset condition, the first wavelength incident light carries out second-order differential operation through the optical chip.

According to an embodiment of the invention, the first radial angle

Is the angle between the incident light with the first wavelength and the normal of the plane of the surface of the photonic crystal film structure 2 on which the incident light with the first wavelength is positioned, i.e. the first radial angle

Is the angle between the incident light of the first wavelength and the z direction. First azimuth angle

The complementary angle of the included angle between the straight line of the projection of the first wavelength incident light in the plane and the straight line of the polarization direction of the projection of the first wavelength incident light in the plane, i.e. the first azimuth angle

Is the included angle between the projection of the first wavelength incident light in the plane of the surface of the photonic crystal film structure 2 and the y direction.

According to an embodiment of the present invention, in the first placeRadial angle

And a first azimuth angle

When the first preset condition is satisfied, the transmissivity t13 of the first wavelength incident light changing along the direction of the wave vector kx1 of the third projection satisfies

Namely, the first-order differential operation is performed on the emergent light with the first wavelength relative to the incident light with the first wavelength.

According to an embodiment of the invention, at the first radial angle

And a first azimuth angle

When the second preset condition is satisfied, the transmissivity t11 of the incident light with the first wavelength changing along the wave vector kr1 direction of the first projection satisfies

Namely, the first wavelength outgoing light is characterized to perform second order differential operation relative to the first wavelength incoming light.

According to an embodiment of the invention, the optical chip 8 may be configured to: at a second radial angle

And a second azimuth angle

And under the condition of meeting a third preset condition, the second-wavelength incident light carries out third-order differential operation through the optical chip. At a second radial angle

And a second azimuth angle

And under the condition of meeting a fourth preset condition, the second-wavelength incident light carries out fourth-order differential operation through the optical chip.

According to an embodiment of the invention, the second radial angle

The angle between the incident light with the second wavelength and the normal of the plane of the surface of the photonic crystal film structure 2 on which the incident light with the second wavelength is incident, i.e. the second radial angle

Is the angle between the incident light of the second wavelength and the z direction. Second azimuth angle

The complementary angle of the included angle between the straight line of the projection of the incident light with the second wavelength in the plane and the straight line of the polarization direction of the projection of the incident light with the second wavelength in the plane is the second azimuth angle

Is the included angle between the projection of the incident light with the second wavelength in the plane of the surface of the photonic crystal film structure 2 and the y direction.

According to an embodiment of the invention, at the second radial angle

And a second azimuth angle

When the third preset condition is satisfied, the transmittance t23 of the second wavelength incident light changing along the direction of the wave vector kx2 of the third projection satisfies

Namely, the third-order differential operation is performed on the emergent light with the second wavelength relative to the incident light with the second wavelength.

According to the inventionExample at the second radial angle

And a second azimuth angle

When the fourth preset condition is satisfied, the transmittance t21 of the incident light with the second wavelength changing along the wave vector kr2 direction of the first projection satisfies

Namely, the emergent light with the second wavelength is characterized to be subjected to fourth-order differential operation relative to the incident light with the second wavelength.

According to the embodiment of the present invention, the wavelength of the first wavelength incident light may be set to 643nm and the wavelength of the second wavelength incident light may be set to 638nm. According to the wavelength of the incident light with the first wavelength and the incident light with the second wavelength and the transmission modulation required correspondingly, the thickness of the glass substrate 1 is 0.17mm, and the refractive index is 1.46; the thickness of the first transmittance film 3 was 56nm, the refractive index was 2.53, and the number of the first transmittance film 3 layers was 20 in total; the second transmittance film 4 has a thickness of 80nm, a refractive index of 1.46, and 20 optical chips 8 in total including the second transmittance film 4. Wherein the first transmittance film 3 may be configured as Si ₃ N ₄ A material of a transmittance film, and the second transmittance film 4 may be configured as SiO ₂ A transmissive film of material, a first transmissive film 3 and a second transmissive film 4 are disposed on the glass substrate 1 in an overlapping manner.

As shown in fig. 2a, when the wavelength of the incident light with the first wavelength is 643nm, the calculated transmittance curve corresponding to the obtained first-order differential operation approximately overlaps with the first fitted transmittance curve of the first-order differential operation in the interval of the first angle of about [ -0.10,0.10], that is, the first-order differential operation is performed on the emergent light with the first wavelength with respect to the incident light with the first wavelength in the interval of the first angle of [ -0.10,0.10 ].

According to the embodiment of the present invention, the first angle may be expressed by a ratio of a wave vector kx1 of the third projection of the first wavelength incident light to a wave vector k01 of the first wavelength incident light, and the angle intervals of the radial angle and the azimuth angle may be obtained by corresponding equations (1), (2) and (3).

According to an embodiment of the present invention, the radial angle may be represented by formula (1):

（1）

wherein the content of the first and second substances,

is the radial angle of the incident light a, kr is the wave vector of the first projection of the incident light a; k0 is the wavevector of the incident light a in space.

According to an embodiment of the present invention, the azimuth angle may be represented by formula (2):

（2）

wherein the content of the first and second substances,

is the azimuth angle of the incident light a, kr is the wave vector of the first projection of the incident light a; kx is the wavevector of the third projection of incident light A.

According to the embodiment of the present invention, the relationship among the wave vector of the first projection, the wave vector of the second projection, and the wave vector of the third projection may be represented by formula (3):

（3）

wherein kr is a wave vector of the first projection; ky is the wave vector of the second projection; kx is the wavevector of the third projection.

According to the embodiment of the present invention, the first preset condition is satisfied by formula (1), formula (2) and formula (3), that is, the first preset condition is obtainedRadial angle

Satisfy the requirement of

[0.14，0.23]First azimuth angle

Satisfy the requirement of

[-4°，4°]In the case of (3), the first wavelength outgoing light is subjected to first order differential operation with respect to the first wavelength incoming light.

FIG. 2b shows a graph of a calculated transmittance curve and a fitted transmittance curve for a second order differential operation according to an embodiment of the present invention.

As shown in fig. 2b, when the wavelength of the first wavelength incident light is 643nm, the calculated transmittance curve of the second order differential operation obtained by the first order differential operation approximately overlaps with the second fitted transmittance curve of the second order differential operation within the second angle range of about [ -0.17,0.17], that is, within the second angle range of [ -0.17,0.17], the first wavelength outgoing light is subjected to the second order differential operation with respect to the first wavelength incident light.

According to the embodiment of the present invention, by performing the numerical derivation process of the first order differential operation like the above, it can be obtained that the first radial angle is the first radial angle when the second preset condition is satisfied

The requirements are met,

[-0.07，0.07]first azimuth angle

Satisfy the requirement of

[-180°，180°]In the case of (a) in (b),the first wavelength outgoing light is subjected to second order differential operation with respect to the first wavelength incoming light.

As shown in fig. 2c, when the wavelength of the incident light with the second wavelength is 638nm, the calculated transmittance curve corresponding to the obtained third-order differential operation approximately overlaps with the third fitted transmittance curve within the third angle range of about [ -0.21,0.21], i.e., the third angle range of [ -0.21,0.21] is that the outgoing light with the second wavelength is subjected to the third-order differential operation with respect to the incident light with the second wavelength.

According to the embodiment of the present invention, by performing the numerical derivation process of the first order differential operation like the above, it can be obtained that the second radial angle is the second radial angle when the third predetermined condition is satisfied

Satisfy the requirement of

[0.12，0.18]Second azimuth angle

Satisfy the requirement of

[-4°，4°]In the case of (1), the first wavelength outgoing light is subjected to third order differential operation with respect to the first wavelength incident light.

As shown in fig. 2d, when the wavelength of the incident light with the first wavelength is 638nm, the calculated transmittance curve corresponding to the obtained fourth order differential operation approximately overlaps with the fourth fitted transmittance curve of the fourth order differential operation in the fourth angle range of about [ -0.24,0.24], that is, the second wavelength outgoing light is subjected to the fourth order differential operation with respect to the incident light with the second wavelength in the fourth angle range of [ -0.24,0.24 ].

According to the embodiment of the present invention, by performing the numerical derivation process of the first order differential operation like the above, it can be obtained that the second radial angle is the second radial angle when the fourth preset condition is satisfied

Satisfy the requirement of

[-0.07，0.07]Second azimuth angle

Satisfy the requirement of

[-180°，180°]In the case of (3), the first wavelength outgoing light is subjected to fourth order differential operation with respect to the first wavelength incoming light.

According to an embodiment of the present invention, another aspect provides a parameter determining method.

As shown in FIG. 3, the method for determining parameters includes operations S310 to S320.

In operation S310, a target transmittance of the optical chip is determined according to the first wavelength incident light, the second wavelength incident light, a fitted transmittance curve corresponding to the first wavelength incident light, and a fitted transmittance curve corresponding to the second wavelength incident light.

In operation S320, optical chip configuration parameters are determined by the transfer matrix theory according to the target transmittance so as to manufacture an optical chip.

According to the embodiment of the invention, the target optical chip structure parameters comprise: the optical chip structure parameters comprise: a target third thickness of the glass substrate and a target third refractive index of the glass substrate of the optical chip; the target first thickness of the first transmittance film of the transmittance modulating film of the photonic crystal film structure of the optical chip disposed on the glass substrate, the target first refractive index of the first transmittance film, the target second thickness of the second transmittance film of the transmittance modulating film of the photonic crystal film structure of the optical chip disposed on the glass substrate, and the target second refractive index of the second transmittance film.

According to an embodiment of the present invention, determining the target transmittance of the optical chip according to the first wavelength incident light, the second wavelength incident light, the fitted transmittance curve corresponding to the differential operation of the first wavelength incident light, and the fitted transmittance curve corresponding to the differential operation of the second wavelength incident light includes:

and determining a first target emergent polarization state of the first wavelength incident light after the first wavelength incident light is emergent from the optical chip according to the wavelength parameter of the first wavelength incident light, a first incident polarization state of the first wavelength incident light before the first wavelength incident light is incident on the optical chip, a first fitted transmittance curve of the first wavelength incident light when first-order differential operation is performed and a second fitted transmittance curve of the first wavelength incident light when second-order differential operation is performed.

And determining a second target emergent polarization state of the second wavelength incident light after the second wavelength incident light is emergent from the optical chip according to the wavelength parameter of the second wavelength incident light, a second incident polarization state before the second wavelength incident light is incident on the optical chip, a third fitted transmittance curve of the second wavelength incident light during third-order differential operation and a fourth fitted transmittance curve of the second wavelength incident light during fourth-order differential operation.

And determining the target transmittance of the optical chip according to the wavelength parameter of the incident light with the first wavelength, the first incident polarization state, the first fitted transmittance curve, the second fitted transmittance curve, the first target emergent polarization state, the wavelength parameter of the incident light with the second wavelength, the second incident polarization state, the third fitted transmittance curve, the fourth fitted transmittance curve and the second target emergent polarization state.

According to the embodiment of the invention, the optical chip structure parameters comprise: a first thickness of the first transmissive film, a first refractive index of the first transmissive film, a second thickness of the second transmissive film, a second refractive index of the second transmissive film, a third thickness of the glass substrate, and a third refractive index of the glass substrate.

According to the embodiment of the invention, determining the structural parameters of the target optical chip according to the target transmissivity by the transfer matrix theory comprises the following steps:

determining a first thickness of the first transmittance film, a first refractive index of the first transmittance film, a second thickness of the second transmittance film, a second refractive index of the second transmittance film, a third thickness of the glass substrate, and a third refractive index of the glass substrate to obtain a transmittance of the optical chip through a transfer matrix theory, and determining a target first thickness, a target first refractive index, a target second thickness, a target second refractive index, a target third thickness, and a target third refractive index in a case where a difference between the obtained transmittance of the optical chip and the target transmittance is minimum.

According to the embodiment of the invention, after the incident light A enters the optical chip 8, when passing through the adjacent first transmittance film 3 and second transmittance film 4, the transmission and reflection can be carried out at the boundary of the films, the transmission and reflection of the light field can be carried out between the adjacent first transmittance film 3 and second transmittance film 4, the transmission and reflection can be carried out through the adjacent first transmittance film 3 and glass substrate 1, or the transmission and reflection can be carried out through the adjacent second transmittance film 4 and glass substrate 1, and the transmission of the light field can be carried out between the transmittance films and between the substrate and the transmittance films. After a series of transmission and reflection transmissions, under the condition that the wavelength and the incident polarization state of the incident light a and the corresponding fitting transmittance curve of the incident light a during first-order differential operation, second-order differential operation, third-order differential operation and fourth-order differential operation are known, the target emergent polarization state of the emergent light B corresponding to the incident light a can be obtained through a transfer matrix theory, the transmittance of the incident light a after passing through the optical chip 8 is further obtained, and the transmittance of the incident light a after passing through the optical chip 8 can be defined as the fitting transmittance curve.

According to the embodiment of the invention, the target emergent polarization state of the emergent light B can be obtained by calculation based on the wavelength parameter of the incident light A, the incident polarization state and the fitted transmissivity curve. Under the condition of obtaining the target emergent polarization state of emergent light B, determining a fitting transmittance curve through the wavelength parameter of incident light A, the incident polarization state, the fitting transmittance curve and the target emergent polarization state of the emergent light B, and then calculating and determining the structural parameters of the target optical chip through a transfer matrix theory.

According to the embodiment of the invention, under the condition that the incident polarization state of the incident light A comprises the polarization component in the z direction and the polarization component in the x direction and does not comprise the polarization component in the y direction, the target emergent polarization state of the emergent light B can be controlled to comprise the polarization component in the opposite direction of the z direction and the polarization component in the y direction and does not comprise the polarization component in the x direction, and then the fitting transmittance curve is determined. And under the condition that the incident polarization state of the incident light A comprises a polarization component in the z direction, a polarization component in the x direction and a polarization component in the y direction, controlling the target emergent polarization state of the emergent light B to comprise a polarization component in the opposite direction of the z direction, a polarization component in the x direction and a polarization component in the y direction, and further determining a fitting transmittance curve.

According to the embodiment of the invention, the specific number of the first thickness, the first refractive index, the second thickness, the second refractive index, the third thickness and the third refractive index, and the first transmittance film 3 and the second transmittance film 4 can be dynamically changed so as to obtain the transmittance of the optical chip through the transfer matrix theory, and under the condition that the difference value between the obtained transmittance of the optical chip and the target transmittance is minimum, the corresponding first thickness, the first refractive index, the second thickness, the second refractive index, the third thickness and the third refractive index are determined as the required target optical chip structure parameters.

According to an embodiment of the present invention, a multi-order differential operation apparatus based on an optical chip is provided.

As shown in fig. 4, the optical chip-based multi-order differential operation apparatus 400 includes: the device comprises an acquisition module 410, an incident light angle adjusting module 420, a modulation module 430, an operation module 440 and a polarization state adjusting module 450.

The obtaining module 410 is configured to obtain incident light of a first wavelength and incident light of a second wavelength.

The incident light angle adjusting module 420 is configured to adjust angles of the first wavelength incident light and the second wavelength incident light to obtain an adjusted first wavelength incident light and an adjusted second wavelength incident light.

The modulation module 430 is configured to modulate information that needs to be subjected to multi-order differential operation onto the adjusted incident light with the first wavelength and the adjusted incident light with the second wavelength, so as to obtain a first modulated light corresponding to the adjusted incident light with the first wavelength and a second modulated light corresponding to the adjusted incident light with the second wavelength.

The operation module 440 is configured to perform multi-order differential operation on the first modulated light and the second modulated light of the modulated light to obtain first outgoing light and second outgoing light including multi-order differential operation results, where the operation module 440 includes an optical chip 8.

The polarization state adjusting module 450 is configured to adjust the polarization states of the first wavelength incident light and the second wavelength incident light, and is further configured to adjust the polarization states of the first emergent light and the second emergent light.

According to the embodiment of the present invention, the obtaining module 410 may be configured to interpret the first wavelength incident light and the second wavelength incident light generated by the external device, and converge the first wavelength incident light and the second wavelength incident light so that the subsequent module obtains the first wavelength incident light and the second wavelength incident light with energy meeting actual calculation requirements.

According to the embodiment of the present invention, the incident light angle adjusting module 420 may be configured to adjust the incident angle of the first wavelength incident light and the second wavelength incident light incident on the modulating module 430 so as to satisfy different requirements of the first order differential operation, the second order differential operation, the third order differential operation, and the fourth order differential operation on the angle.

According to the embodiment of the present invention, the modulation module 430 may be configured to modulate information that needs to be subjected to first-order differential operation, second-order differential operation, third-order differential operation, and fourth-order differential operation onto the first wavelength incident light and the second wavelength incident light. For example, the first wavelength incident light and the second wavelength incident light may be controlled to pass through a sample target with information to achieve information modulation. For example, it is also possible to modulate information directly into the waveform of the first wavelength incident light and the second wavelength incident light by the device.

According to the embodiment of the present invention, the polarization state adjustment module 450 can adjust the polarization states of the first wavelength incident light and the second wavelength incident light, so as to eliminate unnecessary energy in the first wavelength incident light and the second wavelength incident light, thereby obtaining the first order differential operation, the second order differential operation, the third order differential operation and the fourth order differential operation results with high quality and clear imaging.

As shown in fig. 5, the multiple-order differential operation apparatus 400 may specifically include: the polarizer 5, wherein, the polarizer 5 is a polarizer with the transmission direction along the x direction; a focusing objective 6; USAF standard resolution target 7 (United States Air Force resolution test chart, air Force standard resolution target); an optical chip 8; a collection objective 9; the analyzer 10, wherein the analyzer 10 is an analyzer whose transmission direction is along the y direction; an imaging lens 11; a detector 12.

According to the embodiment of the present invention, the polarization components in the y direction corresponding to the first wavelength incident light and the second wavelength incident light can be eliminated by the first wavelength incident light and the second wavelength incident light passing through the polarizer 5, so that the first wavelength incident light and the second wavelength incident light perform the first order differential operation, the second order differential operation, the third order differential operation and the fourth order differential operation under the condition that only the polarization components in the corresponding z direction and the polarization components in the corresponding x direction are included. The first wavelength outgoing light and the second wavelength outgoing light passing through the analyzer 10 can eliminate the polarization component in the x direction corresponding to the first wavelength outgoing light and the second wavelength outgoing light, so that the first wavelength outgoing light and the second wavelength outgoing light can obtain the first order differential operation, the second order differential operation, the third order differential operation and the fourth order differential operation results under the condition that the first wavelength outgoing light and the second wavelength outgoing light only include the corresponding polarization component in the z direction and the corresponding polarization component in the y direction.

According to the embodiment of the invention, the polarizer 5 can be arranged in front of the focusing objective 6 in the optical path, and the analyzer 10 can be arranged in front of the detector 12 in the optical path, and unnecessary direct current components in the optical field energy of the first wavelength incident light and the second wavelength incident light can be eliminated through the polarizer 5 and the analyzer 10 which are orthogonal in the transmission direction, so that the differential operation result is not influenced by background light when the first-order differential operation, the second-order differential operation, the third-order differential operation and the fourth-order differential operation are carried out, and the first-order differential operation, the second-order differential operation, the third-order differential operation and the fourth-order differential operation result which have higher quality and clear imaging are obtained, so that the fitting effect of the calculated transmissivity curve and the fitted transmissivity curve of the first wavelength incident light and the second wavelength incident light is better.

According to the embodiment of the invention, the first wavelength incident light and the second wavelength incident light which are approximately parallel beams and pass through the polarizer 5 are converged on the USAF standard resolution target 7 through the focusing objective 6, and the radial angle and the azimuth angle meeting different requirements can be obtained by setting the parameters of the focusing objective 6.

The optical field carrying the amplitude information in the USAF standard resolution target may be three solid longitudinal lines as shown in fig. 6, or three solid transverse lines formed after the schematic diagram is rotated 90 ° clockwise as shown in fig. 6.

According to the embodiment of the invention, after the first wavelength incident light and the second wavelength incident light pass through the USAF standard resolution target, the amplitude information of the sample with the USAF standard resolution target is obtained, and the edge position of the amplitude change can be extracted by differentiating the optical field of the amplitude information of the sample with the USAF standard resolution target. Since the USAF standard resolution target is an amplitude step type sample, the number of edges of the image edge after the differential operation represents the order of the differential operation.

According to the embodiment of the invention, the first wavelength incident light and the second wavelength incident light pass through the USAF standard resolution target 7 and then pass through the optical chip 8, and the first order differential operation, the second order differential operation, the third order differential operation and the fourth order differential operation are carried out on the optical field of the amplitude information in the USAF standard resolution target.

According to the embodiment of the invention, the optical chip 8 is used for completing the differential operation, the emergent light with the first wavelength and the emergent light with the second wavelength after the polarization state adjustment of the analyzer 10 pass through the imaging lens 11 and are received by the detector 12, and the first-order differential operation, the second-order differential operation, the third-order differential operation and the fourth-order differential operation results can be obtained through detection of the detector 12.

As shown in fig. 7a, after first-order differential operation is performed on three solid longitudinal lines in the USAF standard-resolution target, the inside of the solid longitudinal line light field image after the first-order differential operation is hollowed out, so as to obtain a processed image after the first-order differential operation. The edge extraction as shown by the white dotted line is performed on the processed image after the first-order differential operation, so that the corresponding edge intensity cross-sectional diagram after the first-order differential operation can be obtained.

As shown in fig. 7b, in the edge intensity cross section after the first order differential operation, 1 light intensity peak with abrupt light intensity appears, that is, it means that the solid longitudinal line light field is subjected to the first order differential operation.

According to the embodiment of the present invention, for example, the light intensity may be the amount of data subjected to the normalization process.

As shown in fig. 7c, after second-order differential operation is performed on three solid transverse lines in the USAF standard-resolution target, the interior of the solid transverse line light field image after the second-order differential operation is hollowed out, so as to obtain a processed image after the second-order differential operation. The edge extraction shown by the white dotted line is performed on the processed image after the second order differential operation, so that the corresponding edge intensity cross-sectional schematic diagram after the second order differential operation can be obtained.

As shown in fig. 7d, in the edge intensity cross section after the second order differential operation, 2 light intensity peaks with abrupt light intensity appear, i.e. the solid longitudinal line light field is subjected to the second order differential operation.

As shown in fig. 7e, after three-order differential operations are performed on three solid transverse lines in the USAF standard-resolution target, the interior of the solid transverse line light field image after the three-order differential operations is hollowed out, so as to obtain a processed image after the three-order differential operations. The processed image after the third-order differential operation is subjected to edge extraction as shown by a white dotted line, so that a corresponding edge intensity cross-section schematic diagram after the third-order differential operation can be obtained.

FIG. 7f shows a schematic edge strength cross-sectional view corresponding to FIG. 7e, in accordance with an embodiment of the present invention.

As shown in fig. 7f, in the edge intensity cross section after the third differential operation, 3 light intensity peaks with abrupt light intensity appear, i.e. the solid longitudinal line light field is subjected to the third differential operation.

As shown in fig. 7g, after four-order differential operation is performed on four solid transverse lines in the USAF standard-resolution target, the interior of the solid transverse line optical field image after the four-order differential operation is hollowed out, so as to obtain a processed image after the four-order differential operation. The processed image after the fourth order differential operation is subjected to edge extraction as shown by a white dotted line, so that a corresponding edge intensity cross-sectional diagram after the fourth order differential operation can be obtained.

As shown in fig. 7h, in the edge intensity cross section after the fourth order differential operation, 4 light intensity peaks with abrupt light intensity appear, which means that the solid longitudinal line light field is subjected to the fourth order differential operation.

According to the embodiment of the invention, the optical chip 8 based on the structure of the multi-order differential operation device is used for carrying out transmission modulation on incident light, and different transmission modulation on the incident light is realized by changing the structural parameters of the target optical chip of the optical chip 8, so that the incident light is modulated to realize first-order differential operation, second-order differential operation, third-order differential operation and fourth-order differential operation.

According to the embodiment of the invention, compared with the differential operation performed by an electronic differential operation method, the optical chip performs photon operation according to the light field information, and because the light propagation speed is far higher than the electron propagation speed and the heat loss of light propagation is far less than the heat loss of electron propagation, the differential operation technology realized based on the optical chip has the characteristics of high processing speed and low power consumption.

According to the embodiment of the invention, compared with the optical differential operation method which can only perform single differential operation in the related art, the optical chip 8 based optical differential operation method can simultaneously perform first-order differential operation, second-order differential operation, third-order differential operation and fourth-order differential operation, and is wider in application. The optical chip 8 is a multi-order differential operation realized by utilizing the modulation of a multi-layer film structure, the optical chip 8 does not need to occupy a large amount of space, the miniaturization of an operation device can be realized, and the structure of other optical elements used for assisting the optical chip 8 to carry out the differential operation is simpler, so that the whole volume of multi-order differential operation equipment based on the optical chip is reduced, and the multi-order differential operation equipment does not need to occupy a large amount of space when in actual use. And the multilayer film structure of the optical chip 8 has no surface microstructure, so that the preparation process is simple and the quantitative production is convenient.

According to the embodiment of the invention, because the light beam has a little diameter and the receiving surface of the optical chip 8 has actual size, the light beams can simultaneously carry out first-order differential operation, second-order differential operation, third-order differential operation and fourth-order differential operation, and parallel operation is realized, so that the requirement of large operation amount required in practice is met.

The flowchart and block diagrams in the figures schematically illustrate the architecture, functionality, and operation of possible implementations of systems, methods and computer program products according to various embodiments of the present invention. In this regard, each block in the flowchart or block diagrams may represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical function(s). It should also be noted that, in some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. It will also be noted that each block of the block diagrams or flowchart illustration, and combinations of blocks in the block diagrams or flowchart illustration, can be implemented by special purpose hardware-based systems which perform the specified functions or acts, or combinations of special purpose hardware and computer instructions.

It will be appreciated by a person skilled in the art that various combinations and/or combinations of features described in the various embodiments and/or in the claims of the invention are possible, even if such combinations or combinations are not explicitly described in the invention. In particular, various combinations and/or combinations of the features recited in the various embodiments and/or claims of the present invention may be made without departing from the spirit or teaching of the invention. All such combinations and/or associations fall within the scope of the present invention.

The embodiments of the present invention have been described above. However, these examples are only for illustrating the objects, technical solutions and advantages of the present invention, and are not intended to limit the scope of the present invention. Although the embodiments are described separately above, this does not mean that the measures in the embodiments cannot be used in advantageous combination. The scope of the invention is defined by the appended claims and equivalents thereof. Various substitutions and modifications may be made by those skilled in the art within the spirit and principle of the invention without departing from the scope of the invention, and these substitutions and modifications are intended to be within the scope of the invention.

Claims

1. An optical chip for implementing multi-order differential operations, comprising:

a glass substrate;

a photonic crystal film structure disposed on the glass substrate, the photonic crystal film structure comprising:

a predetermined number of layers of the transmittance modulating film,

wherein the transmittance modulating film includes a first transmittance film and a second transmittance film;

wherein the optical chip for implementing the multi-order differential operation is configured to:

under the condition that the first radial angle and the first azimuth angle meet a first preset condition, first-order differential operation is carried out on incident light with a first wavelength through the optical chip;

under the condition that the first radial angle and the first azimuth angle meet a second preset condition, the first wavelength incident light carries out second-order differential operation through the optical chip,

the first radial angle is an included angle between the first wavelength incident light and a normal of a plane where the surface of the photonic crystal film structure on which the first wavelength incident light is incident is located;

the first azimuth angle is a complementary angle of an included angle between a straight line where the projection of the first wavelength incident light in the plane is located and a straight line where the polarization direction of the projection of the first wavelength incident light in the plane is located; and

under the condition that the second radial angle and the second azimuth angle meet a third preset condition, the second-wavelength incident light carries out third-order differential operation through the optical chip;

performing fourth order differential operation on the second wavelength incident light through the optical chip under the condition that the second radial angle and the second azimuth angle satisfy a fourth preset condition,

the second radial angle is an included angle between the second wavelength incident light and a normal of a plane where the surface of the photonic crystal film structure on which the second wavelength incident light is incident is located;

the second azimuth angle is a complementary angle of an included angle between a straight line where the projection of the second wavelength incident light in the plane is located and a straight line where the polarization direction of the projection of the second wavelength incident light in the plane is located.

2. The chip of claim 1,

the basic transmittance of the optical chip is obtained according to the refractive index of the glass substrate, the refractive index of the first transmittance film, and the refractive index of the second transmittance film;

and performing transmission modulation on the first wavelength incident light and the second wavelength incident light based on the optical chip configured as the basic transmittance, so as to realize the first order differential operation, the second order differential operation, the third order differential operation and the fourth order differential operation.

3. The optical chip for performing multiple-order differential operations according to claim 1,

the refractive index of the first transmittance film is greater than the refractive index of the second transmittance film and the refractive index of the glass substrate, respectively, and the refractive index of the second transmittance film is equal to the refractive index of the glass substrate,

in the photonic crystal film structure connected with the glass substrate, one surface of the first transmissivity film is contacted with the glass substrate, and the other surface of the first transmissivity film is contacted with the second transmissivity film.

4. The optical chip for performing multiple-order differential operations according to claim 1, wherein:

the refractive index of the first transmittance film is respectively greater than the refractive index of the second transmittance film and the refractive index of the glass substrate, and the refractive index of the second transmittance film is not equal to the refractive index of the glass substrate.

5. A method for determining parameters of an optical chip for implementing multi-order differential operations, comprising:

determining a target transmittance of the optical chip according to the first wavelength incident light, the second wavelength incident light, the fitted transmittance curve corresponding to the first wavelength incident light and the fitted transmittance curve corresponding to the second wavelength incident light;

determining the structural parameters of a target optical chip by a transfer matrix theory according to the target transmissivity so as to prepare the optical chip for realizing the multi-order differential operation according to any one of claims 1 to 4;

wherein the target optical chip structure parameters include: a target third thickness of a glass substrate of the optical chip and a target third index of refraction of the glass substrate; the target first thickness of a first transmissivity film of a transmissivity modulation film of a photonic crystal film structure of the optical chip, which is arranged on the glass substrate, the target first refractive index of the first transmissivity film, the target second thickness of a second transmissivity film of a transmissivity modulation film of a photonic crystal film structure of the optical chip, which is arranged on the glass substrate, and the target second refractive index of the second transmissivity film.

6. The method of claim 5, wherein determining the target transmittance of the optical chip based on the first wavelength incident light, the second wavelength incident light, a fitted transmittance curve corresponding to a differential operation performed on the first wavelength incident light, and a fitted transmittance curve corresponding to a differential operation performed on the second wavelength incident light comprises:

determining a first target emergent polarization state after the first wavelength incident light is emergent from the optical chip according to the wavelength parameter of the first wavelength incident light, a first incident polarization state before the first wavelength incident light is incident on the optical chip, a first fitted transmittance curve of the first wavelength incident light when first-order differential operation is performed and a second fitted transmittance curve of the first wavelength incident light when second-order differential operation is performed;

determining a second target emergent polarization state after the second wavelength incident light is emergent from the optical chip according to the wavelength parameter of the second wavelength incident light, a second incident polarization state before the second wavelength incident light is incident on the optical chip, a third fitted transmittance curve of the second wavelength incident light during third-order differential operation and a fourth fitted transmittance curve of the second wavelength incident light during fourth-order differential operation;

and determining the target transmittance of the optical chip according to the wavelength parameter of the first wavelength incident light, the first incident polarization state, the first fitted transmittance curve, the second fitted transmittance curve, the first target emergent polarization state, the wavelength parameter of the second wavelength incident light, the second incident polarization state, the third fitted transmittance curve, the fourth fitted transmittance curve and the second target emergent polarization state.

7. The method of claim 6,

the determining the structural parameters of the target optical chip according to the target transmissivity by the transfer matrix theory comprises the following steps:

determining a first thickness of the first transmittance film, a first refractive index of the first transmittance film, a second thickness of the second transmittance film, a second refractive index of the second transmittance film, a third thickness of the glass substrate, and a third refractive index of the glass substrate so as to obtain a transmittance of the optical chip by the transfer matrix theory, and determining the target first thickness, the target first refractive index, the target second thickness, the target second refractive index, the target third thickness, and the target third refractive index in a case where a difference between the obtained transmittance of the optical chip and the target transmittance is minimum.

8. A multistage differential operation device based on an optical chip that realizes multistage differential operation, comprising:

the acquisition module is used for acquiring incident light with a first wavelength and incident light with a second wavelength;

the incident light angle adjusting module is used for adjusting the angles of the first wavelength incident light and the second wavelength incident light to obtain adjusted first wavelength incident light and adjusted second wavelength incident light;

the modulation module is used for modulating information needing multi-order differential operation to the adjusted first wavelength incident light and the adjusted second wavelength incident light to obtain first modulated light corresponding to the adjusted first wavelength incident light and second modulated light corresponding to the adjusted second wavelength incident light;

an operation module, configured to perform the multi-order differential operation on the first modulated light and the second modulated light to obtain first outgoing light and second outgoing light that include results of the multi-order differential operation, where the operation module includes the optical chip according to any one of claims 1 to 4, which implements the multi-order differential operation;

and the polarization state adjusting module is used for adjusting the polarization states of the first wavelength incident light and the second wavelength incident light and is also used for adjusting the polarization states of the first emergent light and the second emergent light.