WO2021232925A1 - Lcos adjustment method, optical device and reconfigurable optical add-drop multiplexer - Google Patents

Abstract

Disclosed is an LCOS adjustment method, which can be applied to the field of optical communication. The LCOS adjustment method of the present application comprises: adjusting junction lines of the grayscale distribution of gratings in a first area, so that a first light spot covers as few the junction lines of the grayscale distribution of the gratings as possible, wherein the first area is one of K × H areas of LCOS, with K being an integer greater than 0, and H being an integer greater than 1; LCOS is loaded with the grayscale distribution of the gratings; and the first area is an area where a first optical signal forms the first light spot, and the first area is used for redirecting the first optical signal. Crosstalk occurs at the junction lines of the gratings, and the first light spot covers as few junction lines of the gratings as possible by means of adjusting the junction lines of the gratings in the first area, such that crosstalk can be reduced.

Description

LCOS adjustment method, optical device and reconfigurable optical add/drop multiplexer

This application requires the priority of a Chinese patent application filed with the State Intellectual Property Office of China, the application number is 202010436088.7, and the invention title is "LCOS adjustment method, optical device and reconfigurable optical add/drop multiplexer" on May 21, 2020 , Its entire content is incorporated into this application by reference.

Technical field

This application relates to the field of optical communications, and in particular to liquid crystal on silicon (LCOS) adjustment methods, optical devices, and reconfigurable optical add/drop multiplexers.

Background technique

LCOS is a very small matrix liquid crystal device based on the reflection mode. This type of matrix liquid crystal device is fabricated on silicon chips using complementary metal oxide semiconductor (CMOS) technology.

In optical devices that use phase-adjusted optical signals, such as wavelength selective switches (WSS) or dynamic gain flatness filters (DGFF), usually include LCOS. The working principle of LCOS is to load different voltages on different pixels of the LCOS. Due to the birefringence effect of the liquid crystal, different voltages will correspond to different phase retardations, thereby forming a structure similar to a grating. By applying periodic voltages along the Y direction on the pixels of the LCOS, a grating as shown in FIG. 1 can be formed. As shown in FIG. 1, FIG. 1 includes a raster front view 101 and a raster left view 102. The periodic grating 103 is one period of the grating. The periodic grating 103 has a phase with the Y axis. After the beam 104 perpendicular to the Y axis irradiates the blazed grating, because the blazed grating has a phase, the beam 104 will be reflected back at an angle different from the incident angle to form a reflected beam 105. It can also be understood that the beam 104 is deflected in the Y-axis direction.

In practical applications, the grating formed by the LCOS will generate a reflected light beam in a different direction from the reflected light beam 105, causing crosstalk.

Summary of the invention

This application provides an LCOS adjustment method, an optical device and a reconfigurable optical add/drop multiplexer, which can reduce crosstalk.

The first aspect of the present application provides an LCOS adjustment method, including: a controller adjusts the boundary line of the grayscale distribution of the grating in the first region so that the first light spot covers the boundary line of the grayscale distribution of the grating as little as possible. The boundary line of the gray scale distribution of the grating refers to the boundary line of the gratings of different periods in the port direction, and is referred to as the boundary line of the grating hereinafter. In the port direction of the LCOS, there are two boundary lines between a periodic grating and two adjacent periodic gratings. Adjusting the boundary line of the grating means that in the first area, the boundary line of part or all of the gratings is shifted in the port direction. In LCOS, the grayscale distribution of the grating is loaded. For a specific implementation, different voltages can be applied to different pixels of the LCOS. Due to the birefringence effect of the liquid crystal, different voltages will correspond to different phase retardations, thereby forming a structure similar to a grating. LCOS includes K×H areas, K points to the port direction of LCOS, K is an integer greater than 0, H points to the wavelength direction of LCOS, and H is an integer greater than 1. Among them, the first area is one of K×H areas. After the first optical signal is incident on the first area of the LCOS, the first area is used to redirect the first optical signal, such as reflection or transmission, and a first light spot is formed in the first area. In the wavelength direction of the LCOS, different regions can have different grayscale distributions of the grating. Because H is an integer greater than 1, there are at least 2 regions in the wavelength direction of the LCOS.

Among them, the boundary line of the grating will produce crosstalk. In the first aspect of the present application, the controller adjusts the boundary line of the gratings in the first area so that the first light spot covers the boundary line of the gratings as little as possible, so that crosstalk can be reduced.

Based on the first aspect of the present application, in the first implementation manner of the first aspect of the present application, before adjusting the boundary line of the grating in the first region, the controller first obtains the first intensity value of the first optical signal, and the first intensity The value is the power of the first optical signal after redirection. After adjusting the boundary line of the grating in the first region, the controller obtains a second intensity value of the first optical signal, where the second intensity value is the power of the first optical signal after redirection. If the second intensity value is greater than the first intensity value, the first light spot covers as few border lines of the grating as possible. Wherein, the first intensity value may be a target intensity value or a crosstalk intensity value. The target intensity value refers to the power of the first optical signal output by the first optical signal from the target output port, and the crosstalk intensity value refers to the negative value of the power of the first optical signal output by the first optical signal from the non-target output port. The target output port refers to a port where the first optical signal is expected to be output, and the non-target output port refers to a port where the first optical signal generates crosstalk. The power of the first optical signal output by the target output port is generally greater than the power of the first optical signal output by the non-target output port.

To determine whether the first spot covers the boundary line of the grating as little as possible, a positioning sensor needs to be installed in the LCOS to obtain the start position and end position of the first spot in the port direction, and it needs to be calculated between the start position and the end position. The number of junction lines. Compared with the above technical means, it is simpler to judge whether the first light spot covers the boundary line of the grating as little as possible by the intensity value of the first light signal, and the cost is reduced. Wherein, the intensity value of the first light signal can be measured by an intensity sensor, which is simpler to implement than a positioning sensor. In addition, the intensity sensor does not need to be installed on the LCOS, so one intensity sensor can measure multiple LCOS and reduce costs.

Based on the first aspect of the present application, or the first implementation manner of the first aspect, in the second implementation manner of the first aspect of the present application, the controller adjusts the boundary line of the grating in the first region so that the center of the first light spot The distance between the line and the center line of the gray distribution of a periodic grating in the first region is less than A/4, where A is the half-height width of the first light spot. Wherein, the center line of the first light spot is the center line of the first light spot perpendicular to the port direction. The first optical signal is incident on the LCOS, and in the port direction, the energy of the first optical signal is symmetrically distributed along a straight line, and this straight line is the center line of the first light spot. The center line of the first spot will fall within a certain periodic grating in the first area. The center line of the gray distribution of a periodic grating refers to the position of the periodic grating in the port direction equal to (X+Y)/2, and X is The position of the minimum phase of the periodic grating, and Y is the position of the maximum phase of the periodic grating. Among them, the boundary line of the grating will produce crosstalk. The boundary line of the grating in the first area is adjusted by the controller, so that the distance between the center line of the first spot and the gray distribution center line of a periodic grating is less than A/4, so it can Reduce crosstalk.

Based on the first aspect of the present application, or any one of the first implementation to the second implementation of the first aspect, in the third implementation of the first aspect of the present application, the controller passes along the LCOS The port direction shifts the gray distribution of the grating in the first region to adjust the boundary line of the grating. The gray distribution of the translational grating means that the different phases of the periodic grating have the same shift along the port direction without changing the period of the periodic grating. When the gray distribution of the translation grating is adopted, in the first region, the boundary lines of all the gratings are shifted in the port direction. By shifting the gray distribution of the grating, the redirection angle of the first light signal will not change, that is, the target output port corresponding to the first area will not change. The redirection angle of the first optical signal refers to the angle of the first optical signal before the redirection and the first optical signal after the redirection. By shifting the grayscale distribution of the grating, the boundary line of the grating can be adjusted without changing the target output port, and the shifting of the grating can be achieved by a coefficient in the program, so the difficulty of adjusting the boundary line of the grating can be reduced.

Based on the first aspect of the present application, or any one of the first implementation to the second implementation of the first aspect, in the fourth implementation of the first aspect of the present application, the controller can adjust the For the period of the gray distribution of the grating in a region, the controller may also adjust the maximum phase of the gray distribution of the grating in the first region, so that the redirection angle of the first light signal remains unchanged. For the convenience of description, the period of the gray distribution of the grating is referred to as the period of the grating, and the maximum phase of the gray distribution of the grating is referred to as the maximum phase of the grating. Among them, the controller adjusts the boundary line of the grating by adjusting the period and maximum phase of the grating in the first region, which can not only keep the redirection angle of the first light signal unchanged, but also when the first period is less than the second period, The number of targets can be further reduced, and when the first period is greater than the second period, the sensitivity of the first optical signal can also be reduced. Wherein, the number of targets is the number of boundary lines of the grating covered by the first light spot. The first period is the period of the grating in the first area before the controller adjusts the period of the grating in the first area. The second period is the period of the grating in the first area after the controller adjusts the period of the grating in the first area. The first light spot formed by the first optical signal covers the less periodic grating, and the more sensitive the first optical signal is, and the more easily the power of the first optical signal output from the target output port fluctuates up and down. In particular, when the first period is less than the second period, the sensitivity of the first optical signal will be improved. However, by adjusting the boundary line of the grating, the power of the first optical signal output from the target output port can be maintained at a better value.

Based on the first aspect of the application, or any one of the first to the fourth implementations of the first aspect, in the fifth implementation of the first aspect of the application, if the first light spot is If the height is equal to the gray distribution height of a periodic grating in the first region, the boundary line of the grating in the first region is adjusted so that the first light spot matches a periodic grating in the first region. Matching refers to making the first light spot overlap with a periodic grating in the first region as much as possible. If the height of the first light spot is less than the height of the gray distribution of a periodic grating in the first region, the boundary line of the grating in the first region is adjusted so that the first light spot is within a periodic grating in the first region.

Based on any one of the first implementation to the fifth implementation of the first aspect of the present application, in the sixth implementation of the first aspect of the present application, after the controller obtains the second intensity value, The controller adjusts the profile coefficient of the gray scale distribution of the grating in the first region to obtain the third intensity value. Wherein, the first intensity value is the power of the first optical signal after redirection, the third intensity value is obtained after adjusting the topography coefficient of the grayscale distribution of the grating in the first region, and the third intensity value is greater than the second intensity Numerical value, the profile coefficient of the gray scale distribution of the grating is referred to as the profile coefficient of the grating. The third intensity value can also be the target intensity value or the crosstalk intensity value. If the second intensity value is the target intensity value, the third intensity value is the target intensity value; if the second intensity value is the crosstalk intensity value, then the third intensity value Is the crosstalk intensity value. By changing the topography coefficient of the grating, crosstalk can be further reduced.

Based on the first aspect of the present application, or any one of the first implementation to the sixth implementation of the first aspect, in the seventh implementation of the first aspect of the present application, the controller also adjusts the The boundary line of the gratings in the two regions, so that the second light spot covers the boundary line of the grating as little as possible. The second area is one of the K×H areas of the LCOS, the second area is the area where the second light signal forms the second light spot, and the second area can redirect the second light signal. The center line of the second light spot is different from the center line of the first light spot, that is, the first area and the second area belong to different areas in the port direction. K is an integer greater than 1, and the first optical signal and the second optical signal belong to Input optical signals from different input ports. In the case of having multiple input ports, different input optical signals are expanded along the wavelength direction at different positions in the port direction. Compared with the LCOS of a single input port (that is, when K is equal to 1), the height of the LCOS of multiple input ports (that is, when K is greater than 1) in the port direction will not increase exponentially according to the number of input ports, and it is even possible Keep the height constant in the port direction. Therefore, in order that the input optical signals of different input ports do not interfere with each other, it is necessary to reduce the height of the first optical signal in the port direction, which is specifically embodied in reducing the height of the first light spot in the port direction. Reducing the height of the first light spot in the port direction will make the period of the grating covered by the first light spot less, that is, make the first light signal more sensitive. In the case where the first optical signal is more sensitive, the power of the first optical signal output from the target output port will fluctuate more easily. By adjusting the boundary line of the grating, the power of the first optical signal output from the target output port can tend to To stabilize, that is, to reduce the sensitivity of the first optical signal. In particular, because the boundary lines of the gratings are adjusted so that the first light spot covers fewer boundary lines of the gratings, the power of the first optical signal output from the target output port can be maintained at a better value.

Based on the first aspect of the present application, or any one of the first implementation to the seventh implementation of the first aspect, in the eighth implementation of the first aspect of the present application, the controller also adjusts the The boundary line of the gratings in the three regions, so that the third light spot covers the boundary line of the grating as little as possible. The third area is one of the K×H areas of the LCOS, the third area is the area where the third optical signal forms the third light spot, and the third area can redirect the third optical signal. The center line of the third light spot is the same as the center line of the first light spot, that is, the first optical signal and the third optical signal belong to the input optical signals of the same input port, and the wavelength ranges of the first optical signal and the third optical signal are different. In the case that there are multiple regions in the wavelength direction, the first region and the third region can individually adjust the boundary line of the grating, so that the adjustment of the first region or the third region does not affect each other.

Based on the first aspect of the present application, or any one of the first to eighth implementation manners of the first aspect, in the ninth implementation manner of the first aspect of the present application, the first light spot is flat Top spot. The energy distribution of the flat-top light spot in the port direction is relatively even. Therefore, the flat-top light spot needs to pay attention to the number of boundary lines of the grating covered by the entire light spot.

The second aspect of the present application provides an optical device. The optical device includes a first input port, a first output port, a dispersive element and an LCOS. The first input port is used for incident the first incident optical signal to the dispersive element. The dispersive element is used to decompose the first incident optical signal into a first optical signal group of optical signals with different wavelengths, and transmit the first optical signal group to the LCOS, in which the grayscale distribution of the grating is loaded. For a specific implementation, different voltages can be applied to different pixels of the LCOS. Due to the birefringence effect of the liquid crystal, different voltages will correspond to different phase retardations, thereby forming a structure similar to a grating. LCOS includes K×H areas, K points to the port direction of LCOS, K is an integer greater than 0, H points to the wavelength direction of LCOS, and H is an integer greater than 1. Wherein, the first area in the K×H areas is the area where the first light signal forms the first light spot, and the first light signal belongs to the first light signal group. The boundary lines of the gratings in the first region are configured such that the first light spot covers the boundary lines of the grayscale distribution of the gratings as little as possible. LCOS is used to redirect the first optical signal, and transmit the redirected first optical signal to the first output port.

Among them, the boundary line of the grating will produce crosstalk. The boundary lines of the gratings in the first region in the LCOS are configured so that the first light spot covers the boundary lines of the gratings as little as possible, so the optical device including the LCOS can reduce crosstalk.

Based on the second aspect of the present application, in the first implementation of the second aspect of the present application, when the following conditions are met, the boundary line of the grating in the first region is configured so that the first light spot covers the boundary of the grating as little as possible Line: The second intensity value is greater than the first intensity value. The first intensity value is the power of the first optical signal passing through the first output port before the boundary line of the grating in the first region is configured. The second intensity value is the power of the first optical signal passing through the first output port after the boundary line of the grating in the first region is configured. The first intensity value may be a target intensity value or a crosstalk intensity value. When the first output port is the target output port, the first intensity value is the target intensity value. When the first output port is a non-target output port, the first intensity value is the crosstalk intensity value. The target output port refers to a port where the first optical signal is expected to be output, and the non-target output port refers to a port where the first optical signal generates crosstalk. The power of the first optical signal output by the target output port is generally greater than the power of the first optical signal output by the non-target output port.

Based on the second aspect of the present application, or the first implementation manner of the second aspect, in the second implementation manner of the second aspect of the present application, the boundary line of the grating in the first region is configured such that the center line of the first light spot The distance from the center line of the gray distribution of a periodic grating in the first region is less than A/4, where A is the half-height width of the first light spot. Wherein, the center line of the first light spot is the center line of the first light spot in the port direction. The first optical signal is incident on the LCOS, and in the port direction, the energy of the first optical signal is symmetrically distributed along a straight line, and this straight line is the center line of the first light spot. The center line of the first spot will fall within a certain periodic grating in the first area. The center line of the gray distribution of a periodic grating refers to the position where the port direction of the periodic grating is equal to (X + Y)/2, and X is The position of the minimum phase of the periodic grating, and Y is the position of the maximum phase of the periodic grating.

Based on the second aspect of the present application, or any one of the first implementation to the second implementation of the second aspect, in the third implementation of the second aspect of the present application, the grating in the first region The boundary line of is configured such that the boundary line of the grayscale distribution of the grating with as little coverage as possible by the first light spot is obtained by translating the grayscale distribution of the grating in the first region along the port direction. The gray distribution of the translational grating means that the different phases of the periodic grating have the same shift along the port direction without changing the period of the periodic grating. By shifting the gray distribution of the grating, the redirection angle of the first light signal will not change, that is, the target output port corresponding to the first area will not change.

Based on the second aspect of the present application, or any one of the first implementation to the second implementation of the second aspect, in the fourth implementation of the second aspect of the present application, the first optical signal When the redirection angle of is unchanged, the boundary lines of the gratings in the first area are configured so that the first light spot covers the boundary lines of the gratings as little as possible. Wherein, the condition that the redirection angle of the first optical signal remains unchanged is obtained after adjusting the period and maximum phase of the grating in the first region.

Based on the second aspect of the present application, or any one of the first implementation to the fourth implementation of the second aspect, in the fifth implementation of the second aspect of the present application, if the first light spot is The height is equal to the height of the gray distribution of a periodic grating in the first region, so when the height of the first spot matches the gray distribution of a periodic grating in the first region, the boundary line of the grating in the first region It is configured such that the first light spot covers the boundary line of the grayscale distribution of the grating as little as possible. If the height of the first light spot is less than the height of the grayscale distribution of a periodic grating in the first region, then if the first light spot is within the grayscale distribution of a periodic grating in the first region, the boundary of the grating in the first region The lines are arranged so that the first light spot covers the boundary line of the grayscale distribution of the grating as little as possible.

Based on any one of the first implementation to the fifth implementation of the second aspect of the present application, in the sixth implementation of the second aspect of the present application, the grayscale distribution of the grating in the first region is The topography coefficient is configured such that the third intensity value is greater than the second intensity value. The second intensity value is the power of the optical signal at the first output port before the topography coefficient of the gray scale distribution of the grating in the first region is configured. The third intensity value is the power of the optical signal at the first output port after the profile coefficient of the gray scale distribution of the grating in the first region is configured. The profile coefficient of the gray scale distribution of the grating is referred to as the profile coefficient of the grating. The third intensity value can also be the target intensity value or the crosstalk intensity value. If the second intensity value is the target intensity value, the third intensity value is the target intensity value; if the second intensity value is the crosstalk intensity value, then the third intensity value Is the crosstalk intensity value.

Based on the second aspect of the present application, or any one of the first implementation to the sixth implementation of the second aspect, in the seventh implementation of the second aspect of the present application, the optical device further includes a Two input ports. The second input port is used for incident the second incident optical signal to the dispersive element. The dispersive element is also used to decompose the second incident optical signal into a second optical signal group of optical signals with different wavelengths, and transmit the second optical signal group to the LCOS, where the second area of the K×H areas is The second light signal forms the area of the second light spot. The second optical signal belongs to the second optical signal group. The center line of the second light spot is different from the center line of the first light spot, that is, the first area and the second area belong to different areas in the port direction, and K is an integer greater than 1. The boundary lines of the gratings in the second region are configured so that the second light spot covers the boundary lines of the grayscale distribution of the gratings as little as possible. LCOS is also used to redirect the second optical signal.

Based on the second aspect of the present application, or any one of the first implementation to the seventh implementation of the second aspect, in the eighth implementation of the second aspect of the present application, K×H regions The third area is the area where the third light signal forms the third light spot. The third light signal belongs to the first light signal group. The center line of the third light spot is the same as the center line of the first light spot. The wavelength range of the optical signal is different. The boundary lines of the gratings in the third region are arranged so that the third light spot covers the boundary lines of the grayscale distribution of the gratings as little as possible. LCOS is also used to redirect the third optical signal.

Based on the second aspect of the present application, or any one of the first implementation to the eighth implementation of the second aspect, in the ninth implementation of the second aspect of the present application, the first spot is flat Top spot.

For related descriptions of the beneficial effects of the second aspect of the present application, reference may be made to the foregoing related descriptions of the first aspect.

The third aspect of the present application provides a reconfigurable optical add-drop multiplexer (ROADM).

The reconfigurable optical add/drop multiplexer includes: demultiplexer module and multiplexer module. The demultiplexing module is used to download the first optical wavelength signal to the site. The multiplexing module is used to receive the second optical wavelength signal uploaded by the site. Wherein, the demultiplexing module and/or the multiplexing module is the optical device described in any one of the foregoing second aspect or the second aspect, and the optical device is a wavelength selective switch.

A fourth aspect of the present application provides a computer storage medium, characterized in that instructions are stored in the computer storage medium, and when the instructions are executed on a computer, the computer executes any of the first aspect or the first aspect. A method according to an embodiment.

The fifth aspect of the present application provides a computer program product, which is characterized in that when the computer program product is executed on a computer, the computer executes the method according to the first aspect or any one of the implementation manners of the first aspect .

Description of the drawings

Figure 1 is a schematic structural diagram of the grayscale distribution of a grating formed by LCOS;

Figure 2 is another schematic diagram of the grayscale distribution of the grating formed by LCOS;

Figure 3 is a schematic diagram of the structure of WSS;

Figure 4 is a schematic diagram of a structure of DGFF or WE;

5 is a schematic structural diagram of the grayscale distribution of the grating in the first region before adjustment in the embodiment of the application;

FIG. 6 is a schematic flow chart of the LCOS adjustment method in an embodiment of the application;

FIG. 7 is a schematic diagram of the association between different areas and ports of LCOS in an embodiment of the application;

FIG. 8 is a schematic structural diagram of the gray scale distribution of the grating in the first region after adjustment in the embodiment of the application; FIG.

FIG. 9 is a schematic diagram of the gray scale distribution of the grating under different translation amounts in an embodiment of the application;

FIG. 10 is another schematic diagram of the structure of the adjusted gray scale distribution of the grating in the first region in the embodiment of the application; FIG.

FIG. 11 is a schematic diagram of the gray scale distribution of the grating when the topography coefficient is adjusted in the embodiment of the application; FIG.

12 is a schematic diagram of the division of different areas when K is 2 in an embodiment of the application;

FIG. 13 is a schematic diagram of the energy distribution of the flat top spot in an embodiment of the application;

FIG. 14 is a schematic structural diagram of a reconfigurable optical add/drop multiplexer in an embodiment of the application.

Detailed ways

The embodiments of the present application provide an LCOS adjustment method, an optical device, and a reconfigurable optical add/drop multiplexer, which are applied in the field of optical communication and can reduce crosstalk.

LCOS includes many pixels. Different voltages can be applied to the pixels to form different phase delays. When a gradient voltage is applied to a series of continuous pixels, the diffraction effect of the physical grating can be simulated to form the grayscale distribution of the grating. . The gray-scale distribution of the grating is also called the phase distribution. The gray-scale distribution of the grating includes the corresponding relationship between the gradient voltage and the pixel points. Visually speaking, the gray scale distribution of the grating includes the period of the grating, the starting point of the period of the grating, and the maximum phase of the grating. Wherein, the starting point of the period of the grating can be understood as the starting point of the pixel point to which the gradient voltage is applied. The boundary line of the grating can refer to the starting point of the grating period or the maximum phase of the grating. The boundary line of the grating will be described in detail later. The maximum phase of the grating generally corresponds to the pixel where the maximum or minimum voltage is applied. The period of the grating refers to the period of the gradient voltage. For example, it includes 100 pixels along the port direction. From the first pixel to the 10th pixel, the applied voltage is 0.1mV to 1mV, and the applied voltage is from the 11th pixel to the 20th pixel. The values are 0.1mV to 1mV, and so on, until the 100th pixel. The gray scale distribution of the raster includes the height from the first pixel to the 10th pixel (the period of the raster), the position of the 10th pixel or the position of the 11th pixel (the boundary line of the raster), and a voltage of 1mV is applied. Time pixel equivalent phase (the maximum phase of the grating). The period of the grating and the maximum phase of the grating work together to determine the tilt angle of the grating. When the incident light signal is incident on the LCOS loaded with a gradient voltage, the LCOS is equivalent to a mirror or lens placed obliquely, and the incident light signal will therefore be reflected or transmitted. Regardless of whether the incident light signal is reflected or transmitted, the angle of the incident light signal will be deflected, that is, the LCOS redirects the incident light signal. Divide the LCOS into different areas. If the same gradient voltage is applied to different areas, it can be considered that the inclination angles of the different areas are the same, and the redirection angle of the incident light signal is the same; if different gradient voltages are applied to different areas, then It can be considered that the inclination angle of different areas is different, and the redirection angle of the incident light signal is different.

When a gradient voltage is applied to a pixel point, a phase difference will be formed between the pixel point where the maximum voltage is applied and the pixel point where the minimum voltage is applied. And because there is a certain distance between the pixels, then crosstalk will be generated at the boundary line of the grating. As shown in Fig. 2, Fig. 2 is a schematic structural diagram of the gray scale distribution of the grating formed by LCOS. Figure 2 includes a front view of the raster and a left view of the raster. The first light spot 210, the third light spot 209, and the fourth light spot 211 are formed by the light signal incident on the LCOS. A periodic grating 203 includes a first grating area 206 and a second grating area 207. The inclination angle of the first grating area 206 is formed according to the applied voltage gradient, and the inclination angle of the second grating area 207 is formed according to the maximum voltage and the minimum voltage applied. Because the phase of each pixel in the LCOS can be changed in a certain range according to the applied voltage, it is inevitable that there will be a boundary line between the maximum phase and the minimum phase, that is, the boundary line of the grayscale distribution of the grating (can be referred to as The boundary line of the grating). In this application, the boundary line of the grating may refer to the second grating area 207. In the drawing method that does not reflect the second grating area 207, the boundary line of the grating can also be understood as the boundary line 106 in FIG. 1. When the optical signal 204 is incident on the first grating region 206, the angle between the reflected optical signal 205 and the optical signal 204 is the first redirection angle. When the optical signal 204 is incident on the second grating region 207, the angle between the reflected optical signal and the optical signal 204 is the second redirection angle. The first redirection angle is different from the second redirection angle, and the reflected light signal that generates the second redirection angle is crosstalk.

The LCOS adjustment method in this application adjusts the starting point position of the pixel point to which the gradient voltage is applied, thereby moving the boundary line of the grating, so that the light spot formed by the optical signal covers the boundary line of the grating as little as possible, thereby reducing crosstalk. The LCOS adjustment method in this application can adjust optical devices including LCOS, such as WSS, DGFF, WB, and so on.

WSS can switch multi-wavelength optical signals to different ports according to the wavelength to realize wavelength scheduling of communication nodes. As shown in Figure 3, Figure 3 is a schematic diagram of the WSS structure. WSS includes multiple ports 301 as input and output of incident light signals. After the incident light signal enters the WSS from the input port, it needs to be split into two light beams with orthogonal polarization states through a crystal or polarization beam splitter (PBS) 302, and then rotate the polarization state of one of the light beams to make The deflection state of the two beams is aligned with the working polarization state of LCOS306. If polarization-independent LCOS 306 is used, no crystal or polarization beam splitter 302 is required. The incident optical signal after polarization conversion is incident on the periodic grating 305 through the lens 304. The periodic grating 305 is a dispersive element. The periodic grating 305 is used to decompose the incident optical signal into optical signals with different wavelengths and transmit the optical signals to the LCOS306. . The grating formed in the LCOS 306 is different from the periodic grating 305. The periodic grating 305 is a physical entity, and the grating formed in the LCOS 306 is an equivalent grating. Optical signals of different wavelengths are emitted from the periodic grating 305 at different angles, and enter different areas of the LCOS 306 after passing through the lens 304. By adjusting the gray-scale distribution of the gratings in different regions of LCOS306, the corresponding wavelength can be controlled to achieve angular deflection in the port direction 308 perpendicular to the wavelength direction 307. The optical signal after the angular deflection is incident on the Fourier lens 303, The inner lens 303 shifts the position of the optical signal, and the optical signal after the position shift is coupled to a specific output port. Controlling the gray scale distribution of the grating in a region of the LCOS306 can realize that the light signals incident on the region are output from different output ports.

DGFF can achieve attenuation of certain wavelengths. WB can block certain wavelengths. As shown in Figure 4, Figure 4 is a schematic diagram of the structure of DGFF or WE. The incident optical signal is input into the DGFF or WE from the port 401, collimated by the lens 402, and incident on the dispersive element 403. The dispersive element 403 is used to decompose the incident optical signal into optical signals with different wavelengths. Optical signals of different wavelengths are emitted from the dispersive element 403 at different angles, after passing through the lens 404, are focused on different areas of the LCOS405 along the wavelength direction 406, the LCOS405 reflects the optical signals, and the reflected optical signals return to the port 401. Controlling the grayscale distribution of the gratings in different regions of the LCOS405 can change the deflection angle of the optical signal, so that the reflected path deviates from the incident path, and the output optical signal will be attenuated. The greater the deviation, the greater the attenuation. Controlling the gray distribution of gratings in different regions corresponding to different wavelengths can adjust the attenuation and generate a filtering curve. This is the principle of DGFF. If you control the grayscale distribution of the grating in the area corresponding to certain wavelengths, the optical signal will be attenuated greatly, which is equivalent to blocking certain wavelengths; if you control the grayscale distribution of the grating in the area corresponding to certain wavelengths, the optical signal will attenuate Very small, so that certain wavelengths are not attenuated, which is equivalent to passing certain wavelengths.

It should be determined that the above-mentioned structural schematic diagram of WSS, DGFF or WE is just an example, and those skilled in the art can modify it according to relevant knowledge. For example, the output port and the input port of the WE are not the same port, and the lens 402 is not required to collimate the incident light signal. In the case that the optical device includes LCOS, and the LCOS principle is the same, the use of the LCOS adjustment method disclosed in this application to adjust it should fall within the protection scope of this application. In order to illustrate the LCOS adjustment method provided by this application, WSS will be taken as an example below to describe it in detail. The LCOS adjustment method in this application involves the grayscale distribution of the grating, so the first area 201 in FIG. 2 will be used as an example for description. As shown in FIG. 5, FIG. 5 is a schematic structural diagram of the grayscale distribution of the grating formed by the first region 201 before adjustment in an embodiment of the application. FIG. 5 includes a front view and a left view of the first area 201. Exemplarily, the features or content identified by dotted lines in the drawings involved in the embodiments of the present application can be understood as optional operations or optional structures of the embodiments.

Please refer to FIG. 6, which is a schematic flowchart of the LCOS adjustment method in an embodiment of the application.

In step 601, the controller obtains the first intensity value of the first optical signal.

The first intensity value is the power of the first optical signal reflected by the first region in the LCOS. In LCOS, the grayscale distribution of the grating is loaded. LCOS includes K×H areas, K points to the port direction of LCOS, K is an integer greater than 0, H points to the wavelength direction of LCOS, and H is an integer greater than 1. In the embodiments of the present application, K is 1 and H is 3 as an example for description. Referring to FIG. 2, the LCOS includes a first area 201, a third area 202, and a fourth area 208.

Referring to FIG. 3, the first incident optical signal input from the port 301 passes through the dispersive element 305, and the dispersive element 305 decomposes the first incident optical signal into a first optical signal group with optical signals of different wavelengths, and combines the first optical signal An optical signal group is transmitted to LCOS306. The first optical signal group includes a first optical signal, a third optical signal and a fourth optical signal, and different optical signals have different wavelengths. The first optical signal is incident on the first area 201, the third optical signal is incident on the third area 202, and the fourth optical signal is incident on the fourth area 208.

According to the foregoing description of the WSS, it can be seen that by controlling the grayscale distribution of the grating in a region of the LCOS306, the optical signals incident on the region can be output from different output ports. In the embodiment of the present application, an example will be given to illustrate the association relationship between the area and the port in the LCOS. Please refer to FIG. 7, which is a schematic diagram of the association between different areas and ports of the LCOS in an embodiment of the application. The target output port of the first area 201 is the first port 701, the target output port of the third area 202 is the third port 703, the target output port of the fourth area 208 is the fourth port 704, and the fourth port 704 is also used as the application The input port in the embodiment, the second port 702 is not associated with the LCOS area. The target output port of the first optical signal and the target output port of the third optical signal may be the same port, for example, both are the first port 701. In the embodiment of the present application, the first port 701 is associated with the first area, and the third port 703 is associated with the third area for illustrative purposes only.

The first intensity value may be a target intensity value or a crosstalk intensity value. The target intensity value refers to the power of the first optical signal output by the first optical signal from the target output port, and the crosstalk intensity value refers to the negative value of the power of the first optical signal output by the first optical signal from the non-target output port. The target output port refers to a port where the first optical signal is expected to be output, and the non-target output port refers to a port where the first optical signal generates crosstalk. The power of the first optical signal output by the target output port is generally greater than the power of the first optical signal output by the non-target output port. In the embodiment of the present application, the first port 701 is a target output port of the first optical signal, and the second port 702 to the eighth port are non-target output ports of the first optical signal.

In step 602, the controller adjusts the boundary line of the grating in the first region.

The controller adjusts the position of the starting point of the pixel point to which the gradient voltage is applied in the first area, thereby moving the boundary line of the grating, that is, adjusting the boundary line of the grating in the first area. The controller can adjust the boundary line of the grating in the first region by translation, and the controller can also adjust the boundary line of the grating by adjusting the period and maximum phase of the grating in the first region. These two methods will be performed below. A detailed description.

Translation refers to the gray distribution of the translation grating, because the period and maximum phase of the grating are not changed, but the boundary line of the grating is moved, thus producing a translation-like effect. As shown in FIG. 8, FIG. 8 is a schematic structural diagram of the gray scale distribution of the grating formed by the adjusted first region 201 in the embodiment of the application. In Figure 8, the coordinates of the boundary lines of the gratings in the port direction are 14, 34, and 54 respectively. In Figure 5 before adjustment, the coordinates of the boundary lines of the gratings in the port direction are 0, 20, 40, and 60, respectively. Therefore, it can be understood that the grayscale distribution of the grating in FIG. 5 is shifted downward by 6 as a whole, or it can be understood that the grayscale distribution of the grating in FIG. 5 is shifted upward by 14 as a whole. When the gray distribution of the translation grating is adopted, in the first region, the boundary lines of all the gratings are shifted in the port direction. By shifting the gray distribution of the grating, the redirection angle of the first optical signal will not change, that is, the target output port corresponding to the first area will not change, and the target output port of the first optical signal is still the first port 701. Compared with before adjustment, the first light spot 210 covers 4 periodic gratings and 3 boundary lines. After adjustment, the first light spot 210 covers 3 periodic gratings and 2 boundary lines.

When LCOS calculates the grating position, it can be based on the grating formula:

Y=X+move;

Where Y is the phase of the gray distribution of the grating, X is the coordinate of the port direction, and move is the translation amount of the gray distribution of the translation grating. When the translation method is adopted, the controller can adjust the boundary line of the grating in the first region based on the above formula. As shown in FIG. 9, FIG. 9 is a schematic diagram of the gray scale distribution of the grating under different translation amounts in the embodiment of the application. When the period is 20, the translation amounts in Fig. 9 are 0, 5, 10, and 15 respectively.

In order to keep the redirection angle of the first optical signal unchanged, that is, the target output port of the first optical signal does not change, the controller not only needs to adjust the period of the grating in the first area, but also needs to adjust the maximum phase of the grating in the first area. As shown in FIG. 10, FIG. 10 is another schematic structural diagram of the gray scale distribution of the grating formed by the adjusted first region 201 in the embodiment of the application. As shown in Figure 10, the period of the grating is 40, and the maximum phase of the grating is 2π. In Figure 5 before adjustment, the period of the grating is 20, and the maximum phase of the grating is π. Adjusting the boundary line of the grating by adjusting the period and maximum phase of the grating in the first region can not only keep the reorientation angle of the first light signal unchanged, but also can further reduce when the first period is less than the second period. The number of boundary lines of the grating covered by the first light spot. The first period is the period of the grating in the first area before the controller adjusts the period of the grating in the first area. The second period is the period of the grating in the first area after the controller adjusts the period of the grating in the first area. Compared with before adjustment, the first light spot 210 covers 4 periodic gratings and 3 boundary lines. After adjustment, the first light spot 210 covers 3 periodic gratings and 2 boundary lines.

Optionally, after increasing the period and maximum phase of the grating, the controller also translates the boundary line of the grating. By increasing the period of the grating, the periodic grating covered by the first light spot 210 will be reduced, thereby increasing the sensitivity of the first light signal. However, by shifting the boundary line of the grating, the power of the first optical signal output from the target output port can be maintained at a better value. For example, before increasing the period of the grating, it is assumed that the first intensity value of the first optical signal fluctuates between 4-6. After increasing the period of the grating, the first intensity value of the first optical signal is between 2-8. Between fluctuations. By shifting the boundary line of the grating, the first intensity value of the first optical signal can fluctuate between 4-8. Therefore, it is meaningful to translate the boundary line of the grating and increase the period of the grating.

Optionally, regardless of whether it is a translation method or a method of adjusting the period and maximum phase of the grating, after adjusting the boundary line of the grating, the center line of the first spot and the grayscale distribution of a periodic grating in the first region The distance of the center line is less than A/4, and A is the half-height width of the first spot. After adjusting the boundary line of the grating, the center line of the first spot falls within a certain periodic grating. The center line of the gray distribution of a periodic grating refers to the position of the periodic grating equal to (X+Y)/2 in the port direction , X is the position of the minimum phase of the periodic grating, and Y is the position of the maximum phase of the periodic grating. As shown in FIG. 8, the coordinate of the center line 801 of the first light spot is 46, and the coordinate of the center line 802 of the periodic grating is (34+54)/2.

Optionally, if the height of the first spot is equal to the height of the gray distribution of a periodic grating in the first region, the boundary line of the grating in the first region is adjusted so that the first spot is in phase with a periodic grating in the first region. match. Matching refers to making the first light spot overlap with a periodic grating in the first region as much as possible. If the height of the first light spot is less than the height of the gray distribution of a periodic grating in the first region, the boundary line of the grating in the first region is adjusted so that the first light spot is within a periodic grating in the first region.

In step 603, the controller obtains a second intensity value of the first optical signal, where the second intensity value is greater than the first intensity value.

After the controller adjusts the boundary line of the grating in the first region, the controller obtains the second intensity value of the first light signal. The method for obtaining the second intensity value is similar to the method for obtaining the first intensity value. If the first intensity value is obtained through the third port, the second intensity value should also be obtained through the third port. If the second intensity value is greater than the first intensity value, the first light spot covers as few border lines of the grating as possible. To determine whether the first spot covers the boundary line of the grating as little as possible, a positioning sensor needs to be installed in the LCOS to obtain the start position and end position of the first spot in the port direction, and it needs to be calculated between the start position and the end position. The number of junction lines. Compared with the above technical means, it is simpler to judge whether the first light spot covers the boundary line of the grating as little as possible by the intensity value of the first light signal, and the cost is reduced.

The corresponding target output port, such as the first port, is determined in the first area. After the measurement port of the intensity value is determined, such as the target output port, the first intensity value and the second intensity value are bound to the first port. In terms of timing, the first optical signal corresponding to the first intensity value and the first optical signal corresponding to the second intensity value are not an optical signal, but the target output ports of the two first optical signals are both first ports, so the two All first optical signals are called first optical signals. The first optical signal generates different light intensity levels from the first port to the eighth port. Different light intensity levels include +1 level (target level) and crosstalk level. The +1 level is the level with the strongest energy among all the light intensity levels. +1 steps are output at the target output port. At the same time, the first optical signals of other levels will be output as crosstalk signals from other non-target output ports, thereby causing crosstalk between different output ports of the WSS.

Optionally, if the first intensity value and the second intensity value are crosstalk intensity values, the first intensity value and the second intensity value are negative values of the energy of the strongest crosstalk level. For example, the power of the first optical signal at the target output port (the first port) is 60 decibel milliwatts, and the power of the second optical signal at the second port to the eighth port is 20 decibel milliwatts, 10 decibel milliwatts, and 2 Decibel milliwatt, 2 decibel milliwatt, 1 decibel milliwatt, 1 decibel milliwatt, 1 decibel milliwatt. In the case where the first intensity value and the second intensity value are crosstalk intensity values, the first intensity value and the second intensity value are measured at the second port. By measuring the crosstalk of the first optical signal at the second port, before and after the controller adjusts the boundary line of the grating, the change of the first intensity value and the second intensity value, that is, the change of the crosstalk, can be seen more clearly.

Optionally, if the first intensity value and the second intensity value are both +1 level energy, that is, the first intensity value and the second intensity value are the target intensity values. The controller also obtains a third intensity value and a fourth intensity value, where the fourth intensity value is greater than the third intensity index. The fourth intensity value and the third intensity value are both negative values of the energy of the strongest crosstalk level, that is, the first intensity value and the second intensity value are the crosstalk intensity values. The controller not only needs to confirm that the second intensity value is greater than the first intensity value, but also that the fourth intensity value is greater than the third intensity value. Only when the power of the first optical signal output at the target output port increases, it is output at the non-target output port. When the power of the first optical signal is reduced, the controller confirms that the first light spot covers fewer boundary lines of the gratings. The positive and negative conditions are used to determine whether the result of adjusting the boundary line of the grating is beneficial, which can increase reliability. If the first intensity value and the second intensity value are negative values of the energy of the strongest crosstalk level, the third intensity value and the fourth intensity value are the target intensity values, which are contrary to the above content, and will not be repeated here.

In step 604, the controller adjusts the topography coefficient of the grating in the first region.

After the controller obtains the second intensity value, the controller adjusts the topography coefficient of the grating in the first region. When LCOS calculates the grating position, it can be based on the grating formula:

Y=a*(X+move)+b*(X+move) ² +c*(X+move) ³ +...;

Where Y is the phase of the gray distribution of the grating, and X is the coordinate of the port direction. b and c are the topography coefficients of the grating, and move is the translation amount of the gray distribution of the aforementioned translation grating. a is used to adjust the first-order linear slope of the grating. In order to keep the redirection angle of the first optical signal unchanged, the slope of the first-order linearity is unchanged. The coefficient b is used to adjust the second-order parabolic coefficient of the grating, and the coefficient c is used to adjust the third-order curve coefficient. The coefficients of move, a, b, and c work together to fully cover all possible topography possibilities in the grating. As shown in FIG. 11, FIG. 11 is a schematic diagram of the gray scale distribution of the grating when the topography coefficient is adjusted under the condition that a is unchanged in the embodiment of the present application.

The gray scale distribution map 1101 is a gray scale distribution map of the raster when a is equal to 1, b is equal to 0, and c is equal to 0.

The gray scale distribution map 1102 is the gray scale distribution map of the raster when a is equal to 1, b is equal to 20, and c is equal to 0.

The gray scale distribution map 1103 is the gray scale distribution map of the raster when a is equal to 1, b is equal to -20, and c is equal to 0.

The gray distribution map 1104 is the gray distribution map of the raster when a is equal to 1, b is equal to 0, and c is equal to 20.

The gray scale distribution map 1105 is the gray scale distribution map of the raster when a is equal to 1, b is equal to 20, and c is equal to -20.

The gray scale distribution map 1106 is the gray scale distribution map of the raster when a is equal to 1, b is equal to 20, and c is equal to 20.

In step 605, the controller obtains a third intensity value of the first optical signal, and the third intensity value is greater than the second intensity value.

After the controller adjusts the profile coefficient of the grating in the first region, the controller obtains the third intensity value of the first light signal. The method for obtaining the third intensity value is similar to the method for obtaining the second intensity value.

Optionally, the controller further adjusts the boundary lines of the gratings in the second area, so that the second light spot covers the boundary lines of the gratings as little as possible. The second area is one of the K×H areas of the LCOS, the second area is the area where the second light signal forms the second light spot, and the second area can redirect the second light signal. The center line of the second light spot is different from the center line of the first light spot, that is, the first area and the second area belong to different areas in the port direction. K is an integer greater than 1, and the first optical signal and the second optical signal belong to Input optical signals from different input ports. In the case of having multiple input ports, different input optical signals are expanded along the wavelength direction at different positions in the port direction. As shown in Fig. 12, Fig. 12 is a schematic diagram of the division of different areas when K is 2 in an embodiment of the application. The center line 1204 of the first light spot 1203 and the center line 1201 of the second light spot 1202 are not the same center line. As long as it is determined that the center line of the light spot is not the same, it can be determined that the two light spots fall in different areas. Therefore, there is no need to have clear boundaries for the division of areas in the port direction. For example, in the λ1 area in FIG. 12, the dividing line for the area in the port direction falls on a periodic grating. The manner in which the controller adjusts the boundary line of the gratings in the second area is similar to the manner in which the controller adjusts the boundary line of the gratings in the first area.

Compared with the LCOS of a single input port (that is, when K is equal to 1), the height of the LCOS of multiple input ports (that is, when K is greater than 1) in the port direction will not increase exponentially according to the number of input ports, and it is even possible Keep the height constant in the port direction. Therefore, in order that the input optical signals of different input ports do not interfere with each other, it is necessary to reduce the height of the first optical signal in the port direction, which is specifically embodied in reducing the height of the first light spot in the port direction. As shown in FIG. 12, the height of the first light spot 1203 in the port direction is only half of the height of the first light spot 210 in FIG. Reducing the height of the first light spot in the port direction will make the period of the grating covered by the first light spot less, that is, make the first light signal more sensitive. In the case where the first optical signal is more sensitive, the power of the first optical signal output from the target output port will fluctuate more easily. By adjusting the boundary line of the grating, the power of the first optical signal output from the target output port can tend to To stabilize, that is, to reduce the sensitivity of the first optical signal. In particular, because the boundary lines of the gratings are adjusted so that the first light spot covers fewer boundary lines of the gratings, the power of the first optical signal output from the target output port can be maintained at a better value.

Optionally, the controller further adjusts the boundary lines of the gratings in the third area so that the third light spot covers the boundary lines of the gratings as little as possible. The third area is one of the K×H areas of the LCOS, the third area is the area where the third optical signal forms the third light spot, and the third area can redirect the third optical signal. The center line of the third light spot is the same as the center line of the first light spot, that is, the first optical signal and the third optical signal belong to the input optical signals of the same input port, and the wavelength ranges of the first optical signal and the third optical signal are different. In the case that there are multiple regions in the wavelength direction, the first region and the third region can individually adjust the boundary line of the grating, so that the adjustment of the first region or the third region does not affect each other. As shown in FIG. 12, the center line 1204 of the third light spot 1205 in the third region is the same as the center line 1204 of the first light spot 1203.

Optionally, the first spot is a flat top spot. The energy distribution of the flat-top light spot in the port direction is relatively even. Therefore, the flat-top light spot needs to pay attention to the number of boundary lines of the grating covered by the entire light spot. As shown in FIG. 13, FIG. 13 is a schematic diagram of the energy distribution of the flat top spot 1301 in an embodiment of the application.

The LCOS adjustment method in the embodiment of the present application is described above, and the optical device in the embodiment of the present application is described below. The optical device in this application is an optical device including LCOS, such as WSS, DGFF, WB, etc.

The optical device includes a first input port, a first output port, a dispersive element and an LCOS. The first input port is used for incident the first incident optical signal to the dispersive element. The dispersive element is used to decompose the first incident optical signal into a first optical signal group of optical signals with different wavelengths, and transmit the first optical signal group to the LCOS, in which the grayscale distribution of the grating is loaded. LCOS includes K×H regions, K is an integer greater than 0, and H is an integer greater than 1. Wherein, the first area in the K×H areas is the area where the first light signal forms the first light spot, and the first light signal belongs to the first light signal group. The boundary lines of the gratings in the first region are configured so that the first light spot covers the boundary lines of the gratings as little as possible. LCOS is used to redirect the first optical signal, and transmit the redirected first optical signal to the first output port.

For the related description in the optical device, please refer to the related description in the aforementioned LCOS adjustment method. The first input port can refer to the aforementioned fourth port 704 in FIG. 7, and the first output port can refer to the aforementioned first port 701 in FIG. 7. The first input port and the first output port may be the same port. For example, the fourth port 704 serves as both an input port and an output port corresponding to the fourth area.

Optionally, when the following conditions are met, the boundary line of the gratings in the first region is configured such that the first light spot covers the boundary line of the gratings with as little as possible: the second intensity value is greater than the first intensity value.

Optionally, the boundary line of the grating in the first region is configured so that the distance between the center line of the first light spot and the center line of the gray distribution of a periodic grating in the first region is less than A/4, where A is the distance of the first light spot Half-height width.

Optionally, the boundary line of the grating in the first region is configured so that the boundary line of the grayscale distribution of the grating with the first light spot covering as little as possible is, after the grayscale distribution of the grating in the first region is translated along the port direction owned. The gray distribution of the translational grating means that the different phases of the periodic grating have the same shift along the port direction without changing the period of the periodic grating. By shifting the gray distribution of the grating, the redirection angle of the first light signal will not change, that is, the target output port corresponding to the first area will not change.

Optionally, when the redirection angle of the first optical signal remains unchanged, the boundary lines of the gratings in the first region are configured so that the first light spot covers the boundary lines of the gratings as little as possible. Wherein, the condition that the redirection angle of the first optical signal remains unchanged is obtained after adjusting the period and maximum phase of the grating in the first region.

Optionally, if the height of the first light spot is equal to the height of the gray distribution of a periodic grating in the first region, then in the case where the height of the first light spot matches the gray distribution of a periodic grating in the first region The boundary line of the gratings in the first region is configured so that the first light spot covers the boundary line of the grayscale distribution of the grating as little as possible. If the height of the first light spot is less than the height of the grayscale distribution of a periodic grating in the first region, then if the first light spot is within the grayscale distribution of a periodic grating in the first region, the boundary of the grating in the first region The lines are arranged so that the first light spot covers the boundary line of the grayscale distribution of the grating as little as possible.

Optionally, the topography coefficient of the gray scale distribution of the grating in the first region is configured such that the third intensity value is greater than the second intensity value. The second intensity value is the power of the optical signal at the first output port before the topography coefficient of the gray scale distribution of the grating in the first region is configured. The third intensity value is the power of the optical signal at the first output port after the profile coefficient of the gray scale distribution of the grating in the first region is configured. The profile coefficient of the gray scale distribution of the grating is referred to as the profile coefficient of the grating. The third intensity value can also be the target intensity value or the crosstalk intensity value. If the second intensity value is the target intensity value, the third intensity value is the target intensity value; if the second intensity value is the crosstalk intensity value, then the third intensity value Is the crosstalk intensity value.

Optionally, the optical device further includes a second input port. The second input port is used for incident the second incident optical signal to the dispersive element. The dispersive element is also used to decompose the second incident optical signal into a second optical signal group of optical signals with different wavelengths, and transmit the second optical signal group to the LCOS, where the second area of the K×H areas is The second light signal forms the area of the second light spot. The second optical signal belongs to the second optical signal group. The center line of the second light spot is different from the center line of the first light spot, that is, the first area and the second area belong to different areas in the port direction, and K is an integer greater than 1. The boundary lines of the gratings in the second area are configured so that the second light spot covers the boundary lines of the gratings as little as possible. LCOS is also used to redirect the second optical signal.

Optionally, the third area in the K×H areas is the area where the third light signal forms the third light spot, the third light signal belongs to the first light signal group, and the center line of the third light spot is the same as the center line of the first light spot The same, the first optical signal and the third optical signal have different wavelength ranges. The boundary lines of the gratings in the third region are arranged so that the third light spot covers the boundary lines of the grayscale distribution of the gratings as little as possible. LCOS is also used to redirect the third optical signal.

Optionally, the first spot is a flat top spot.

The optical device in the embodiment of the present application is described above, and the reconfigurable optical add/drop multiplexer in the embodiment of the present application is described below.

Please refer to FIG. 14, which is a schematic structural diagram of a reconfigurable optical add/drop multiplexer in an embodiment of this application.

The reconfigurable optical add/drop multiplexer of this embodiment includes a demultiplexing module 1401 and a multiplexing module 1402; the ROADM of this embodiment may also include a drop module 1403, an add module 1404, a receiver 1406, and a transmitter 1406.

The demultiplexing module 1401 is used to download the first optical wavelength signal to the current site, and the first optical wavelength signal may refer to the first optical signal in the aforementioned optical device.

The multiplexing module 1402 is configured to receive the second optical wavelength signal uploaded by the current site, and the second optical wavelength signal is an optical signal with a different wavelength from the first optical signal.

Among them, the aforementioned optical device of the demultiplexing module and/or the multiplexing module, the optical device is WSS.

In the several embodiments provided in this application, it should be understood that the disclosed system, device, and method can be implemented in other ways. For example, the device embodiments described above are merely illustrative, for example, the division of the units is only a logical function division, and there may be other divisions in actual implementation, for example, multiple units or components may be combined or It can be integrated into another system, or some features can be ignored or not implemented. In addition, the displayed or discussed mutual coupling or direct coupling or communication connection may be indirect coupling or communication connection through some interfaces, devices or units, and may be in electrical, mechanical or other forms.

The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the objectives of the solutions of the embodiments.

In addition, the functional units in the various embodiments of the present application may be integrated into one processing unit, or each unit may exist alone physically, or two or more units may be integrated into one unit. The above-mentioned integrated unit can be implemented in the form of hardware or software functional unit.

If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer readable storage medium. Based on this understanding, the technical solution of the present application essentially or the part that contributes to the existing technology or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium , Including several instructions to make a computer device (which may be a personal computer, a server, or a network device, etc.) execute all or part of the steps of the methods described in the various embodiments of the present application. The aforementioned storage media include: flash drives, mobile hard drives, ROM, RAM, magnetic disks, or optical disks and other media that can store program codes.

Claims (23)

1. A method for adjusting a liquid crystal on silicon LCOS, which is characterized in that it comprises:

   Adjust the boundary line of the grayscale distribution of the grating on the first area so that the first light spot covers the boundary line of the grayscale distribution of the grating as little as possible, and the first area is among the K×H areas of the LCOS In an area of the LCOS, the K points to the port direction of the LCOS, the K is an integer greater than 0, the H points to the wavelength direction of the LCOS, the H is an integer greater than 1, and the LCOS is loaded with some For the gray scale distribution of the grating, the first area is an area where the first light signal forms the first light spot, and the first area is used to redirect the first light signal.
2. The method according to claim 1, characterized in that, before the adjusting the boundary line of the grayscale distribution of the grating in the first region, the method further comprises:

   Acquiring a first intensity value of the first optical signal, where the first intensity value is the power of the first optical signal after redirection;

   After adjusting the boundary line of the grayscale distribution of the grating in the first region, the method further includes:

   Acquiring a second intensity value of the first optical signal, where the second intensity value is the power of the first optical signal after redirection;

   When the following conditions are met, the first light spot covers as little as possible the boundary line of the grayscale distribution of the grating:

   The second intensity value is greater than the first intensity value.
3. The method according to claim 1 or 2, wherein the adjusting the boundary line of the gray scale distribution of the grating in the first region comprises:

   Adjust the boundary line of the grayscale distribution of the grating in the first region, so that the distance between the center line of the first light spot and the centerline of the grayscale distribution of a periodic grating in the first region is less than A/4 , The A is the half-height width of the first light spot.
4. The method according to any one of claims 1 to 3, wherein said adjusting the boundary line of the gray distribution of the grating of the first region comprises:

   Translating the grayscale distribution of the grating in the first region along the port direction of the LCOS.
5. The method according to any one of claims 1 to 3, wherein said adjusting the boundary line of the gray distribution of the grating of the first region comprises:

   Adjusting the period of the grayscale distribution of the grating in the first region;

   The method also includes:

   The maximum phase of the grayscale distribution of the grating in the first region is adjusted, so that the redirection angle of the first optical signal remains unchanged.
6. The method according to any one of claims 1 to 5, wherein the adjusting the boundary line of the gray scale distribution of the grating in the first region comprises:

   If the height of the first light spot is equal to the height of the grayscale distribution of a periodic grating in the first region, the boundary line of the grayscale distribution of the grating in the first region is adjusted so that the first The light spot is matched with a periodic grating in the first region;

   If the height of the first light spot is smaller than the height of the grayscale distribution of a periodic grating in the first region, adjust the boundary line of the grayscale distribution of the grating in the first region so that the first light spot Within a periodic grating in the first region.
7. The method according to any one of claims 2 to 6, wherein after obtaining the second intensity value, the method further comprises:

   Adjusting the profile coefficient of the gray scale distribution of the grating in the first region;

   Obtain a third intensity value, where the first intensity value is the power of the first optical signal after redirection, and the third intensity value is the shape of the gray scale distribution of the grating in the first region. After the appearance coefficient is obtained, the third intensity value is greater than the second intensity value.
8. The method according to any one of claims 1 to 7, wherein the method further comprises:

   The boundary line of the grayscale distribution of the grating in the second region is adjusted so that the second light spot covers the boundary line of the grayscale distribution of the grating in the second region as little as possible, and the second region is the K× of the LCOS One of the H areas, the second area is the area where the second light signal forms the second light spot, the second area is used to redirect the second light signal, the second light spot The center line of is different from the center line of the first light spot.
9. The method according to any one of claims 1 to 8, wherein the method further comprises:

   Adjust the boundary line of the grayscale distribution of the grating in the third region so that the third light spot covers as little as possible the boundary line of the grayscale distribution of the grating in the third region, and the third region is the K× of the LCOS One of the H areas, the third area is the area where the third light signal forms the third light spot, the third area is used to redirect the third light signal, the third light spot The center line of is the same as the center line of the first light spot.
10. The method according to any one of claims 1 to 9, wherein the first light spot is a flat top light spot.
11. An optical device, characterized in that it comprises:

    The first input port, the first output port, the dispersive element and the liquid crystal on silicon LCOS;

    The first input port is used for incident the first incident optical signal to the dispersive element;

    The dispersive element is used to decompose the first incident optical signal into a first optical signal group having optical signals of different wavelengths, and transmit the first optical signal group to the LCOS, and the LCOS includes K× H areas, the K points to the port direction of the LCOS, the K is an integer greater than 0, the H points to the wavelength direction of the LCOS, the H is an integer greater than 1, and the LCOS is loaded with a grating The gray scale distribution of the K×H areas is the area where the first light signal forms the first light spot, the first light signal belongs to the first light signal group, and the first light signal The boundary line of the gray scale distribution of the grating of the region is configured so that the first light spot covers the boundary line of the gray scale distribution of the grating as little as possible;

    The LCOS is used to redirect the first optical signal, and transmit the redirected first optical signal to the first output port.
12. The optical device according to claim 11, wherein when the following conditions are met, the boundary line of the grayscale distribution of the grating in the first region is configured so that the first spot covers as little as possible The boundary line of the gray distribution of the grating:

    The second intensity value is greater than the first intensity value, wherein the first intensity value is the first output port that passes through the first output port before the boundary line of the grayscale distribution of the grating in the first region is configured The power of an optical signal, and the second intensity value is the power of the first optical signal passing through the first output port after the boundary line of the grayscale distribution of the grating in the first region is configured.
13. The optical device according to claim 11 or 12, wherein the boundary line of the grayscale distribution of the grating in the first region is configured such that the center line of the first light spot and the first region The distance between the center line of the gray distribution of a periodic grating is less than A/4, and the A is the half-height width of the first light spot.
14. The optical device according to any one of claims 11 to 13, wherein the boundary line of the grayscale distribution of the grating in the first region is configured so that the first light spot covers as little as possible The boundary line of the gray scale distribution of the grating is obtained by translating the gray scale distribution of the grating in the first region along the port direction of the LCOS.
15. The optical device according to any one of claims 11 to 13, wherein under the condition that the redirection angle of the first optical signal remains unchanged, the gray scale distribution of the grating in the first region The boundary line of is configured such that the first light spot covers as little as possible the boundary line of the grayscale distribution of the grating;

    Wherein, the condition that the redirection angle of the first light signal remains unchanged is obtained after adjusting the period and maximum phase of the grayscale distribution of the grating in the first region.
16. The optical device according to any one of claims 11 to 15, wherein if the height of the first light spot is equal to the height of the gray distribution of a periodic grating in the first region, the When the first light spot matches the gray scale distribution of a periodic grating in the first region, the boundary line of the gray scale distribution of the grating in the first region is configured so that the first light spot covers As few as possible the boundary lines of the gray scale distribution of the grating;

    If the height of the first light spot is smaller than the height of the grayscale distribution of a periodic grating in the first region, then in the case where the first light spot is within the grayscale distribution of a periodic grating in the first region The boundary line of the grayscale distribution of the grating in the first region is configured so that the first light spot covers the boundary line of the grayscale distribution of the grating as little as possible.
17. The optical device according to any one of claims 12 to 16, wherein the topography coefficient of the gray scale distribution of the grating in the first region is configured such that the third intensity value is greater than the first intensity value. Two intensity values, the second intensity value is the power of the optical signal at the first output port before the topography coefficient of the gray scale distribution of the grating in the first region is configured, and the third intensity value After the profile coefficient of the gray scale distribution of the grating in the first region is configured, the power of the optical signal of the first output port.
18. The optical device according to any one of claims 11 to 17, wherein the device further comprises a second input port;

    The second input port is used for incident a second incident optical signal to the dispersive element;

    The dispersive element is also used to decompose the second incident optical signal into a second optical signal group having optical signals of different wavelengths, and transmit the second optical signal group to the LCOS, wherein the K The second area among the ×H areas is the area where the second light signal forms a second light spot, the second light signal belongs to the second light signal group, and the center line of the second light spot is the same as the first light spot. The center line of is different, and the boundary line of the grayscale distribution of the grating in the second region is configured so that the second light spot covers the boundary line of the grayscale distribution of the grating in the second region as little as possible.
19. The optical device according to any one of claims 11 to 18, wherein the third area in the K×H areas is an area where a third light signal forms a third light spot, and the third light signal Belongs to the first optical signal group, the center line of the third light spot is the same as the center line of the first light spot, and the boundary line of the gray scale distribution of the grating in the third region is configured so that the The boundary line of the gray-scale distribution of the grating in the third region where the three light spots cover as little as possible.
20. The optical device according to any one of claims 11 to 19, wherein the first light spot is a flat top light spot.
21. A reconfigurable optical add/drop multiplexer, which is characterized in that it comprises:

    Demultiplexer module, multiplexer module;

    The demultiplexing module is used to download the first optical wavelength signal to the site;

    The multiplexing module is configured to receive the second optical wavelength signal uploaded by the site;

    Wherein, the demultiplexing module and/or the multiplexing module is the optical device according to any one of claims 11 to 20, and the optical device is a wavelength selective switch.
22. A computer storage medium, characterized in that instructions are stored in the computer storage medium, and when the instructions are executed on a computer, the computer executes the method according to any one of claims 1 to 10.
23. A computer program product, characterized in that, when the computer program product is executed on a computer, the computer executes the method according to any one of claims 1 to 10.

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