Wavelength selective switch apparatus with pre-tilt angle adjustment, and method for using same

Abstract

A wavelength selective switch apparatus with pre-tilt angle adjustment, and a method for using same. The apparatus comprises a optical transceiving end (1), a grating assembly (2), a deflection element (3), a phase grating (4) and an optical switching engine (5), which are sequentially arranged along a optical path, wherein an optical signal emitted by a transmitting end (11) in the optical transceiving end (1) is received by the grating assembly (2) and divided into a plurality of optical signals of different wavelengths, the optical signals of different wavelengths are transmitted to the phase grating (4) through the deflection element (3), and tilt angles of the optical signals of different wavelengths are changed by means of the deflection element (3), such that the optical signals of different wavelengths correspond to the same grating period; and the phase grating (4) on the optical switching engine (5) divides each of the optical signals of different wavelengths into diffracted light of different orders, and returns same to the optical transceiving end (1) along the optical path, wherein some diffracted light of a preset order is received by a corresponding receiving end (12) in the optical transceiving end (1). Since optical signals of different wavelengths correspond to the same grating period, diffracted light of the same order but different wavelengths converges, thereby preventing crosstalk caused by divergence of the diffracted light of the same order.

Description

A wavelength selective switch device with pre-offset angle adjustment and its usage method

[0001] Cross-reference of related applications

[0002] This application claims priority to the following patent application:

[0003] (1) A Chinese patent application filed on June 18, 2024, with application number 202410783992.3, entitled “A wavelength selection switch device with pre-offset angle adjustment and a method of use”. Technical Field

[0004] This invention relates to the field of optical communication technology, and in particular to a wavelength selection switch device and method of use with pre-offset angle adjustment. Background Technology

[0005] In the field of optical communication, wavelength division multiplexing (WDM) systems are an important means of expanding communication capacity. Signals of different wavelengths can represent different signal channels, and a signal transmission link system can be constructed by building an optical layer network.

[0006] Wavelength selective switches (WSS) play a crucial role in optical wavelength division multiplexing (WDM) systems. They are core components in optical branching multiplexing systems, enabling the switching or blocking of any wavelength or wavelength combination at any communication port, thereby facilitating signal uploading and downloading in the transmission link.

[0007] In existing WSS (Wide-Switch System) based on Liquid Crystal on Silicon (LCoS) optical switching engines, light signals of different wavelengths are divided into different orders of diffraction light by a diffraction grating and then reflected by the optical switching engine to the optical receiver. Different optical receivers receive the diffraction light of their respective orders. However, the problem is that the receivers in the optical transceiver do not receive all orders of diffraction light. Since the first-order diffraction light has the highest energy and the least loss, existing receivers generally select the first-order diffraction light for reception. The separated zero-order diffraction light is emitted outwards and will not be discussed here. As for other orders of diffraction light, because the grating periods of different wavelengths of light signals are inconsistent, and the incident and exit angles of other orders of diffraction light of different wavelengths of light signals are different on the optical switching engine, the other orders of diffraction light of different wavelengths are far apart and have a large degree of divergence. This causes other orders of diffraction light that should not be received to diverge to the receiver and be received by the receiver, causing crosstalk between ports.

[0008] Therefore, overcoming the shortcomings of the existing technology is an urgent problem to be solved in this technical field.

[0009] Application content

[0010] The technical problem to be solved by this invention is how to solve the crosstalk problem caused by diffusion of diffracted light of the same order at different wavelengths in a wavelength selective switch.

[0011] The present invention adopts the following technical solution:

[0012] In a first aspect, a wavelength selection switch device with pre-offset angle adjustment is provided, comprising an optical transceiver 1, a grating assembly 2, a deflection element 3, a phase grating 4 and an optical switching engine 5 arranged sequentially along the optical path, wherein the path of the optical signal emitted from the transmitter 11 in the optical transceiver 1 is the optical path.

[0013] The optical signal emitted from the transmitter 11 in the optical transceiver 1 is received by the grating assembly 2 and divided into multiple optical signals of different wavelengths; the optical signals of different wavelengths are transmitted to the phase grating 4 through the deflection element 3, wherein the deflection angle of the optical signals of different wavelengths is changed by the deflection element 3 so that the grating period corresponding to the optical signals of different wavelengths is consistent.

[0014] The phase grating 4 divides each different wavelength light signal into diffracted light of different orders. All diffracted light of different orders is reflected by the optical switching engine 5 and passes sequentially through the phase grating 4, the deflection element 3 and the grating assembly 2. The diffracted light of different wavelengths of preset orders is received by the corresponding receiver 12 in the optical transceiver 1. Among them, diffracted light of the same order of different wavelengths converges.

[0015] Preferably, the deflection element 3 includes multiple preset regions, each preset region being used to allow light signals of a corresponding wavelength to pass through both sides of the preset region, thereby adjusting the deflection angle of the light signals of the corresponding wavelength.

[0016] Preferably, the formula for the included angle between the two sides of the preset region is:

[0017] |(n-1)θ1|=θ inafter (λ1)-θ inbefore (λ1)|;

[0018] Where n is the refractive index of deflection element 3, λ1 is the wavelength, θ1 is the angle between the two sides of the preset region corresponding to the optical signal of wavelength λ1, and θ inafter (λ1) is the angle between the light signal with wavelength λ1 and the normal of the light switching engine 5 after passing through the deflection element 3, θ inbefore (λ1) is the angle between the optical signal with wavelength λ1 and the normal of the optical switching engine 5 when the optical signal has not passed through the deflection element 3.

[0019] Preferably, the wavelength selection switch device for pre-bias angle adjustment further includes a first dispersive lens group 61, a first switching lens group 71, a second switching lens group 72, and a second dispersive lens group 62, wherein:

[0020] The first dispersive lens group 61 and the first switching lens group 71 are sequentially arranged between the optical transceiver 1 and the grating assembly 2 along the optical path, and the second switching lens group 72 and the second dispersive lens group 62 are sequentially arranged between the grating assembly 2 and the phase grating 4 along the optical path.

[0021] Preferably, the wavelength selection switch device for pre-offset adjustment further includes a third dispersive lens group 63 and a third switching lens group 73;

[0022] The third dispersive lens group 63 receives the light signal emitted from the transmitter 11 in the optical transceiver 1 and reflects the light signal to the third switching lens group 73. After passing through the third switching lens group 73, the light signal is incident on the grating assembly 2, split into multiple light signals of different wavelengths by the grating assembly 2, and reflected back to the third switching lens group 73. After passing through the third switching lens group 73, the multiple light signals of different wavelengths are received by the third dispersive lens group 63 and reflected onto the phase grating 4. The phase grating 4 splits each light signal of different wavelengths into diffracted light of different orders. All diffracted light of different orders is reflected by the optical switching engine 5 and transmitted toward the optical transceiver 1. The diffracted light of different wavelengths of preset orders is received by the corresponding receiver 12 in the optical transceiver 1.

[0023] Preferably, the deflection element 3 is located in the optical path of the plurality of optical signals of different wavelengths and is disposed between the optical switching engine 5 and the third dispersive lens group 63.

[0024] Preferably, the deflection element 3 is located in the optical path of the plurality of optical signals of different wavelengths, and is disposed between the third dispersive lens group 63 and the third switching lens group 73 or between the third switching lens group 73 and the grating assembly 2.

[0025] Preferably, a first pre-processing unit 81 and a second pre-processing unit 82 are further provided between the optical transceiver 1 and the grating assembly 2;

[0026] The first preprocessing unit 81 is located on the outgoing optical path of the transmitter 11 and is used to perform beam shaping on the optical signal emitted by the transmitter 11.

[0027] The second preprocessing unit 82 is located on the receiving optical path of the receiving end 12 and is used to perform beam shaping on the optical signal directed to the receiving end 12.

[0028] Secondly, a method for using a wavelength selective switch device with pre-offset angle adjustment is provided, for application on the aforementioned wavelength selective switch device with pre-offset angle adjustment, comprising:

[0029] The optical signal emitted from the transmitter 11 in the optical transceiver 1 is received by the grating assembly 2 and divided into multiple optical signals of different wavelengths;

[0030] The light signals of different wavelengths are transmitted to the phase grating 4 through the deflection element 3. The deflection angle of the light signals of different wavelengths is changed by the deflection element 3 so that the grating period corresponding to the light signals of different wavelengths is consistent.

[0031] The phase grating 4 divides each optical signal of different wavelengths into diffracted light of different orders, wherein diffracted light of the same order in optical signals of different wavelengths converges.

[0032] All diffracted light of different orders is reflected by the optical switching engine 5 and passes sequentially through the phase grating 4, the deflection element 3 and the grating assembly 2. Diffracted light of different wavelengths and preset orders is received by the corresponding receiver 12 in the optical transceiver 1.

[0033] Preferably, the deflection element 3 includes multiple preset regions, and the step of changing the deflection angle of light signals of different wavelengths through the deflection element 3 specifically includes:

[0034] The light signal of the corresponding wavelength passes through the two sides of the corresponding preset area, thereby adjusting the deflection angle of the light signal of the corresponding wavelength.

[0035] This invention provides a wavelength selection switch device and method for pre-adjusting the deflection angle, comprising an optical transceiver 1, a grating assembly 2, a deflection element 3, a phase grating 4, and an optical switching engine 5 arranged sequentially along the optical path. The optical signal emitted from the transmitter 11 in the optical transceiver 1 is received by the grating assembly 2 and divided into multiple optical signals of different wavelengths. The optical signals of different wavelengths are passed through the deflection element 3 and directed to the phase grating 4. The deflection element 3 changes the deflection angle of the optical signals of different wavelengths, making the grating periods corresponding to the different wavelengths consistent. The phase grating 4 divides each optical signal of different wavelengths into diffracted light of different orders. All diffracted light of different orders is reflected by the optical switching engine 5 towards the optical transceiver 1, and a portion of the diffracted light of the preset order is received by the corresponding receiver 12 in the optical transceiver 1. Since the grating periods corresponding to different wavelengths are consistent, diffracted light of the same order at different wavelengths converges, avoiding crosstalk caused by the divergence of diffracted light of the same order. Attached Figure Description

[0036] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments of the present invention will be briefly described below. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.

[0037] Figure 1 is a front view of a wavelength selection switch device with pre-offset angle adjustment provided in an embodiment of the present invention;

[0038] Figure 2 is a top view of a wavelength selection switch device with pre-offset angle adjustment provided in an embodiment of the present invention;

[0039] Figure 3 is a schematic diagram of the diffraction equation of the optical switching engine in a wavelength selective switching device with pre-offset angle adjustment provided in an embodiment of the present invention in a coordinate system.

[0040] Figure 4 is a schematic diagram of the deflection element in a wavelength selective switch device with pre-deflection angle adjustment provided in an embodiment of the present invention;

[0041] Figure 5 is a front view of another wavelength selection switch device with pre-offset angle adjustment provided in an embodiment of the present invention;

[0042] Figure 6 is a top view of another wavelength selection switch device with pre-offset angle adjustment provided in an embodiment of the present invention;

[0043] Figure 7 is a top view of another wavelength selection switch device with pre-offset angle adjustment provided in an embodiment of the present invention;

[0044] Figure 8 is a top view of another wavelength selection switch device with pre-offset angle adjustment provided in an embodiment of the present invention;

[0045] Figure 9 is a top view of another wavelength selection switch device with pre-offset angle adjustment provided in an embodiment of the present invention;

[0046] Figure 10 is a flowchart of a method for using a wavelength selective switch device with pre-offset angle adjustment according to an embodiment of the present invention;

[0047] The attached figures are numbered as follows:

[0048] Optical transceiver 1; transmitter 11; receiver 12; grating assembly 2; deflection element 3; phase grating 4; optical switching engine 5; first dispersive lens group 61; first switching lens group 71; second switching lens group 72; second dispersive lens group 62; third dispersive lens group 63; third switching lens group 73; first pre-processing unit 81; second pre-processing unit 82. Detailed Implementation

[0049] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0050] In the description of this invention, it should be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this disclosure and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this disclosure.

[0051] In the description of this invention, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of embodiments of this disclosure, unless otherwise stated, "a plurality of" means two or more. Furthermore, for example, the description may use the prefix "A" or "B" to describe the same type of nouns as two independent entities. In this case, the corresponding features defined with "A" and "B" are used only to distinguish between similar entities and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features.

[0052] As used in this invention, “about,” “approximately,” or “approximately” includes the stated value and the average value within an acceptable range of deviation from a particular value, wherein the acceptable range of deviation is determined by a person skilled in the art taking into account the measurement under discussion and the error associated with the measurement of the particular quantity, i.e., the limitations of the measurement system.

[0053] Unless the context otherwise requires, throughout the specification and claims, the term "comprising" is interpreted as openly inclusive, meaning "including, but not limited to." In the description of the specification, terms such as "one embodiment," "some embodiments," "exemplary embodiment," "example," "specific example," or "some examples" are intended to indicate that a particular feature, structure, material, or characteristic associated with that embodiment or example is included in at least one embodiment or example of this disclosure. The illustrative representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics mentioned may be included in any suitable manner in any one or more embodiments or examples; that is, although they may be incorporated into embodiments or examples using the above terms for reasons such as order and position, it does not limit them to be incorporated in combination by a single embodiment or example.

[0054] Furthermore, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0055] Example 1:

[0056] Embodiment 1 of the present invention provides a wavelength selective switch device with pre-offset angle adjustment, as shown in Figures 1 and 2. It includes an optical transceiver 1, a grating assembly 2, a deflection element 3, a phase grating 4, and an optical switching engine 5 arranged sequentially along the optical path. The path of the optical signal emitted from the transmitter 11 in the optical transceiver 1 is the optical path. In this embodiment, the X arrow in the figures indicates the vertical direction, and the Y arrow in the figures indicates the horizontal direction. Figure 1 is a front view of the device, and Figure 2 is a top view of the device.

[0057] In this embodiment, the wavelength selection switch device with pre-bias angle adjustment can be used as a WSS (Wavelength Selector Switch) to switch or block any wavelength or wavelength combination at any communication port, thereby enabling signal uploading and downloading in the transmission link. The basic principle of the WSS is to map light signals of different wavelengths to different positions in space through a diffraction grating and optical lens system, and then switch the corresponding wavelength light signals to different ports through the optical switching engine 5. In this embodiment, the optical switching engine 5 can be of the LCoS (Liquid CoS) type. It is worth mentioning that in practical application scenarios, the phase grating 4 and the optical switching engine 5 can be regarded as the same device, that is, the phase grating 4 is located on the optical switching engine 5.

[0058] In this embodiment, the optical transceiver 1 includes multiple transmitters 11 and at least one receiver 12. The transmitters 11 emit optical signals, the grating assembly 2 divides the optical signals into different wavelengths, the phase grating 4 divides each wavelength into multiple levels of diffracted light, and the receiver 12 receives diffracted light of corresponding orders for different wavelengths. For example, one receiver 12 receives first-order diffracted light of all wavelengths, while other orders of diffracted light of various wavelengths are either received by other receivers 12 or not received at all. The optical path refers to the optical path from the transmitter 11 to the optical switching engine 5.

[0059] The problem with the existing technology is that the receivers 12 in the optical transceiver 1 do not receive all orders of diffracted light. First-order diffracted light has the highest energy and lowest loss, and the distance between first-order diffracted light of different wavelengths is very close with almost no diffusion. Therefore, existing receivers 12 generally select first-order diffracted light for reception, while the separated zero-order diffracted light is directed outwards and will not be discussed here. However, for other orders of diffracted light, because the grating periods of different wavelengths of optical signals are inconsistent, and the incident and exit angles of other orders of diffracted light of different wavelengths on the optical switching engine 5 are different, the distance between other orders of diffracted light of different wavelengths is relatively large, resulting in a large degree of divergence. This causes other orders of diffracted light that should not have been received to diverge to the receiver 12 and be received by the receiver 12, causing crosstalk between ports. Therefore, to address the above problem, this embodiment includes a deflection element 3, specifically designed as follows:

[0060] As shown in Figure 2, the optical signal emitted from the transmitter 11 in the optical transceiver 1 is received by the grating assembly 2 and divided into multiple optical signals of different wavelengths. The optical signals of different wavelengths are directed to the phase grating 4 through the deflection element 3. The deflection angle of the optical signals of different wavelengths is changed by the deflection element 3 so that the grating period corresponding to the optical signals of different wavelengths is consistent. As shown in Figure 1, the phase grating 4 divides each optical signal of different wavelengths into diffracted light of different orders. All diffracted light of different orders is reflected by the optical switching engine 5 and passes sequentially through the phase grating 4, the deflection element 3 and the grating assembly 2. The dashed lines in Figure 1 represent the diffracted light of different levels separated by the phase grating 4. Diffracted light of the same order of different wavelengths converges. Diffracted light of different preset orders of different wavelengths is received by the corresponding receiver 12 in the optical transceiver 1.

[0061] In this embodiment, the deflection element 3 can be a metasurface element, a wedge element, a mirror element, or a grating element, etc. The deflection element 3 is used to deflect the light signal passing through at different angles according to different wavelengths, thereby adjusting the incident angle of light signals of different wavelengths on the optical switching engine 5.

[0062] The diffraction equation for optical switching engine 5 is as follows:

[0063] d(λ)sinθ out (λ)+d(λ)sinθ in (λ)=mλ;

[0064] Figure 3 shows the diffraction equation of the optical switching engine 5 in a coordinate system, where d(λ) is the equivalent phase grating period corresponding to the optical signal with wavelength λ, and θ out (λ) is the emission angle of the optical signal with wavelength λ from the optical switching engine 5, θ in (λ) is the incident angle of the optical signal with wavelength λ from the optical switching engine 5, and m is the diffraction order of the optical signal.

[0065] The relationship between the incident and exit angles of the optical signal of the corresponding wavelength on the optical switching engine 5 and the distance between the transmitter 11 and the receiver 12 is as follows:

[0066] f(λ)|θ out(λ) -θ in(λ) |=H;

[0067] Where f(λ) is the equivalent focal length of the optical signal with wavelength λ in the vertical direction, and θ out (λ) is the emission angle of the optical signal with wavelength λ from the optical switching engine 5, θ in (λ) is the incident angle of the optical signal with wavelength λ from the optical switching engine 5, and H is the height difference in the vertical direction between the receiver 12 and the transmitter 11 corresponding to the optical signal with wavelength λ.

[0068] As can be seen from the diffraction equation of the optical switching engine 5, the grating period of the optical signal of the corresponding wavelength can be adjusted by adjusting the incident angle and the exit angle of the optical signal on the optical switching engine 5. When the grating periods of two optical signals of different wavelengths are the same, the diffracted light of the same order of different wavelengths approaches each other, which can be regarded as the diffracted light of the same order of different wavelengths converging.

[0069] In this embodiment, after the light signals of each wavelength pass through the deflection element 3, the deflection element 3 changes the deflection angle of the light signals of different wavelengths, that is, changes the incident angle of the light signals of different wavelengths on the optical switching engine 5. Through the above adjustment, the grating period corresponding to the light signals of different wavelengths is made consistent, so that the diffracted light of the same order of different wavelengths converges, thereby avoiding excessive divergence of diffracted light of other orders of different wavelengths, which would cause crosstalk when received by other receivers 12.

[0070] In this embodiment, since the deflection element 3 needs to adjust the deflection angle for different wavelengths of light signals, the deflection element 3 needs to be customized for each wavelength of light signal that needs adjustment. This ensures that the light signal of the corresponding wavelength can be deflected at a preset angle after passing through the corresponding area on the deflection element 3. The preset angle deflection makes the grating period of the light signal of the corresponding wavelength become a preset value and consistent with the grating period of other wavelengths of light signals after deflection, thus achieving convergence of diffracted light of the same order at different wavelengths. Therefore, this embodiment also involves the following design:

[0071] As shown in Figure 4, the deflection element 3 includes multiple preset regions. Each preset region is used to allow light signals of a corresponding wavelength to pass through both sides of the preset region, thereby adjusting the deflection angle of the light signals of the corresponding wavelength.

[0072] The formula for the included angle between the two sides of the preset area is:

[0073] |(n-1)θ1|=θ inafter (λ1)-θ inbefore (λ1)|;

[0074] Where n is the refractive index of deflection element 3, λ1 is the wavelength, θ1 is the angle between the two sides of the preset region corresponding to the optical signal of wavelength λ1, and θ inafter (λ1) is the angle between the light signal with wavelength λ1 and the normal of the light switching engine 5 after passing through the deflection element 3, θ inbefore (λ1) is the angle between the optical signal with wavelength λ1 and the normal of the optical switching engine 5 when the optical signal has not passed through the deflection element 3.

[0075] In this embodiment, taking Figure 3 as an example, when light signals of different wavelengths pass through the deflection element 3, the two sides of the deflection element 3 in Figure 3 pass through. If the included angle between the two sides of the preset area corresponding to the light signal of wavelength λ1 is θ1 in Figure 3, then the light signal of wavelength λ1 needs to be close to the surface marked with included angle θ1 in Figure 3; if the included angle between the two sides of the preset area corresponding to the light signal of wavelength λ1 is θ2 in Figure 3, then the light signal of wavelength λ1 needs to be close to the surface marked with included angle θ2 in Figure 3.

[0076] In this embodiment, the customization of the preset area mainly requires determining the included angle between the two sides of the preset area. This needs to be set according to the diffraction equation of the optical switching engine 5 and the formula for the included angle between the two sides of the preset area, as follows:

[0077] It is important to predetermine the grating period after the adjustment of the deflection element 3 for light signals of different wavelengths. The grating period should be the same for all wavelengths after adjustment. Substituting the corresponding grating period and the specified wavelength into the diffraction equation of the optical switching engine 5 yields the incident angle θ of the light signal of the specified wavelength on the optical switching engine 5 after passing through the deflection element 3. inafter Then, after measurement, the incident angle θ of the light signal of the specified wavelength on the light switching engine 5 before passing through the deflection element 3 is obtained. inbefore , θ inafter and θ inbefore Substituting the values ​​into the formula for the included angle between the two sides of the preset area, the included angle between the two sides of the preset area is calculated.

[0078] To illustrate the above method more intuitively, the following specific examples are provided:

[0079] In this example, the grating periods of both the λ1 wavelength optical signal and the λ2 wavelength optical signal need to be adjusted to d1.

[0080] Therefore, substituting d1 and λ1 into the diffraction equation, we obtain: when the grating period of the optical signal with wavelength λ1 is d1, the incident angle θ of the optical signal with wavelength λ1 on the optical switching engine 5 is... inafter (λ1), and then the incident angle θ of the optical signal with wavelength λ1 on the optical switching engine 5 without passing through the deflection element 3 is obtained according to the actual optical path measurement. inbefore (λ1), θ inafter (λ1), θ inbefore Substituting (λ1) and the refractive index n of the deflection element 3 into the formula for the angle between the two sides of the preset region, we obtain the angle θ1 between the two sides of the preset region through which the light signal of wavelength λ1 passes on the deflection element 3.

[0081] Similarly, substituting d1 and λ2 into the diffraction equation, we obtain: when the grating period of the λ2 wavelength optical signal is d1, the incident angle θ of the λ2 wavelength optical signal on the optical switching engine 5 is... inafter (λ2), and then the incident angle θ of the λ2 wavelength optical signal on the optical switching engine 5 without passing through the deflection element 3 is obtained according to the actual optical path measurement. inbefore (λ2), θ inafter (λ2), θ inbefore Substituting (λ2) and the refractive index n of the deflection element 3 into the formula for the angle between the two sides of the preset region, we obtain the angle θ2 between the two sides of the preset region through which the light signal of wavelength λ2 passes on the deflection element 3.

[0082] Based on the above steps, the included angle between the two sides of the preset area corresponding to the optical signal with wavelength λ1 and optical signal with wavelength λ2 on the deflection element 3 is set, thereby realizing the customization of the deflection element 3 for optical signals of different wavelengths.

[0083] In this embodiment, to ensure the rationality of the optical path of the wavelength selective switch, corresponding devices are also required to focus or collimate the optical signal. Therefore, this embodiment also involves the following design:

[0084] As shown in Figures 5 and 6, Figure 5 is a front view of the device, and Figure 6 is a top view of the device. The wavelength selection switch device with pre-offset angle adjustment further includes a first dispersive lens group 61, a first switching lens group 71, a second switching lens group 72, and a second dispersive lens group 62, wherein:

[0085] The first dispersive lens group 61 and the first switching lens group 71 are sequentially arranged between the optical transceiver 1 and the grating assembly 2 along the optical path, and the second switching lens group 72 and the second dispersive lens group 62 are sequentially arranged between the grating assembly 2 and the phase grating 4 along the optical path.

[0086] The first dispersive lens group 61 is used to focus the light signal emitted from the transmitter 11 in the horizontal direction, and the first switching lens group 71 is used to focus the light signal emitted from the transmitter 11 in the vertical direction. After the light signal is focused in the horizontal and vertical directions, it is divided into light signals of different wavelengths in the horizontal direction after passing through the grating assembly 2. The second switching lens group 72 is used to collimate all the light signals of different wavelengths in the vertical direction, and the second dispersive lens group 62 is used to collimate all the light signals of different wavelengths in the horizontal direction.

[0087] After being focused and collimated in the vertical and horizontal directions, the optical signals of different wavelengths are incident on the optical switching engine 5 in the same horizontal direction.

[0088] It should be noted that in this embodiment, regardless of how many lens groups are set for collimation or focusing, it is sufficient to ensure that the deflection element 3 is set between the grating assembly 2 and the optical switching engine 5. The deflection element 3 can achieve the effect of adjusting the deflection angle at any position between the grating assembly 2 and the optical switching engine 5.

[0089] It is worth mentioning that, in this embodiment, the optical transceiver 1 needs to perform beam shaping and polarization beam splitting processing after emitting the optical signal or before receiving it, or only needs to perform beam shaping. Therefore, this embodiment also involves the following design:

[0090] As shown in Figures 5 and 6, a first preprocessing unit 81 and a second preprocessing unit 82 are also provided between the optical transceiver 1 and the grating assembly 2.

[0091] The first preprocessing unit 81 is located on the outgoing optical path of the transmitter 11 and is used to perform beam shaping on the optical signal emitted by the transmitter 11.

[0092] The second preprocessing unit 82 is located on the receiving optical path of the receiving end 12 and is used to perform beam shaping on the optical signal directed to the receiving end 12.

[0093] In this embodiment, the outgoing optical path of the transmitting end 11 is the transmission path of the optical signal emitted by the transmitting end 11, and the receiving optical path of the receiving end 12 is the transmission path of the optical signal received by the transmitting end 11. In this embodiment, both the first preprocessing unit 81 and the second preprocessing unit 82 include a beam shaping lens for beam shaping of the optical signal, and may also include a polarization beam splitter for polarization beam splitting of the optical signal.

[0094] Example 2:

[0095] Based on Embodiment 1, Embodiment 2 of the present invention, considering the integration of the device, can employ a folded optical path, enabling multiple components in the device to be reused, thereby reducing the number of multiple identical components in the device, reducing costs, and enhancing the integration of the device. Therefore, this embodiment provides another wavelength selection switch device with pre-offset angle adjustment, as shown in Figure 7. Figure 7 is a top view of the device, including: a third dispersive lens group 63 and a third switching lens group 73, wherein:

[0096] As shown in Figure 7, the third dispersive lens group 63 receives the light signal emitted from the transmitter 11 in the optical transceiver 1. The third dispersive lens group 63 is used to focus the light signal in the horizontal direction and reflect the light signal to the third switching lens group 73; the third switching lens group 73 is used to focus the light signal in the vertical direction. After passing through the third switching lens group 73, the light signal is incident on the grating assembly 2; it is split into multiple light signals of different wavelengths by the grating assembly 2 and reflected back to the third switching lens group 73. In this embodiment, the grating assembly 2 can be a prism grating, which has both beam splitting and reflection functions. The third switching lens group 73 is used to collimate light signals of different wavelengths in the vertical direction; after passing through the third switching lens group 73, the multiple light signals of different wavelengths are received by the third dispersive lens group 63, which is used to collimate light signals of different wavelengths in the horizontal direction and is reflected by the third dispersive lens group 63 onto the phase grating 4. The phase grating 4 divides each light signal of different wavelengths into diffracted light of different orders. All diffracted light of different orders is reflected by the optical switching engine 5 and transmitted toward the optical transceiver 1. The diffracted light of different wavelengths of preset orders is received by the corresponding receiver 12 in the optical transceiver 1.

[0097] As shown in Figure 7, the above process demonstrates that the optical path is folded by the grating assembly 2. In this embodiment, before the optical signal passes through the grating assembly 2, the third dispersive lens group 63 and the third switching lens group 73 are used to focus the optical signal in the horizontal and vertical directions, respectively. After the optical signal passes through the grating assembly 2, the optical signal, which has been divided into multiple wavelengths, passes through the third dispersive lens group 63 and the third switching lens group 73 again. The third dispersive lens group 63 and the third switching lens group 73 are used to collimate the optical signal in the horizontal and vertical directions, respectively. This achieves secondary multiplexing of the third dispersive lens group 63 and the third switching lens, reduces the cost of the device, and improves the integration of the device.

[0098] In this embodiment, as shown in Figures 7-9 (all top views of the device), since the deflection element 3 can be positioned anywhere between the grating assembly 2 and the optical switching engine 5, the deflection element 3 needs to be located on the optical paths of multiple different wavelengths of light signals split from the second grating assembly 2. Based on this, as shown in Figure 7, the deflection element 3 can be located between the optical switching engine 5 and the third dispersive lens group 63; as shown in Figure 8, the deflection element 3 can be located between the third dispersive lens group 63 and the third switching lens group 73; and as shown in Figure 9, the deflection element 3 can be located between the third switching lens group 73 and the grating assembly 2.

[0099] Example 3:

[0100] Based on Embodiments 1 and 2, Embodiment 3 of the present invention provides a method for using a wavelength selective switch device with pre-offset angle adjustment, which is applied to the aforementioned wavelength selective switch device with pre-offset angle adjustment, as shown in FIG10. The method includes:

[0101] In step 101, the optical signal emitted from the transmitter 11 in the optical transceiver 1 is received by the grating assembly 2 and divided into multiple optical signals of different wavelengths.

[0102] In step 102, the light signals of different wavelengths are transmitted to the phase grating 4 through the deflection element 3. The deflection angle of the light signals of different wavelengths is changed by the deflection element 3 so that the grating period corresponding to the light signals of different wavelengths is consistent.

[0103] In step 103, the phase grating 4 divides each optical signal of different wavelengths into diffracted light of different orders, wherein diffracted light of the same order in optical signals of different wavelengths converges.

[0104] In step 104, all diffracted light of different orders is reflected by the optical switching engine 5 and passes sequentially through the phase grating 4, the deflection element 3 and the grating assembly 2. The diffracted light of different wavelengths and preset orders is received by the corresponding receivers 12 in the optical transceiver 1.

[0105] The deflection element 3 includes multiple preset regions, and the method of changing the deflection angle of light signals of different wavelengths through the deflection element 3 specifically includes:

[0106] The light signal of the corresponding wavelength passes through the two sides of the corresponding preset area, thereby adjusting the deflection angle of the light signal of the corresponding wavelength.

[0107] The formula for the included angle between the two sides of the preset area is:

[0108] |(n-1)θ1|=θ inafter (λ1)-θ inbefore (λ1)|;

[0109] Where n is the refractive index of deflection element 3, λ1 is the wavelength, θ1 is the angle between the two sides of the preset region corresponding to the optical signal of wavelength λ1, and θ inafter (λ1) is the angle between the light signal with wavelength λ1 and the normal of the light switching engine 5 after passing through the deflection element 3, θ inbefore (λ1) is the angle between the optical signal with wavelength λ1 and the normal of the optical switching engine 5 when the optical signal has not passed through the deflection element 3.

[0110] In this embodiment, the customization of the preset area mainly requires determining the included angle between the two sides of the preset area. This needs to be set according to the diffraction equation of the optical switching engine 5 and the formula for the included angle between the two sides of the preset area, as follows:

[0111] It is important to predetermine the grating period after the adjustment of the deflection element 3 for light signals of different wavelengths. The grating period should be the same for all wavelengths after adjustment. Substituting the corresponding grating period and the specified wavelength into the diffraction equation of the optical switching engine 5 yields the incident angle θ of the light signal of the specified wavelength on the optical switching engine 5 after passing through the deflection element 3. inafter Then, after measurement, the incident angle θ of the light signal of the specified wavelength on the light switching engine 5 before passing through the deflection element 3 is obtained. inbefore , θ inafter and θ inbefore Substituting the values ​​into the formula for the included angle between the two sides of the preset area, the included angle between the two sides of the preset area is calculated.

[0112] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A wavelength selective switching device with pre-offset angle adjustment, characterized in that, It includes an optical transceiver (1), a grating assembly (2), a deflection element (3), a phase grating (4), and an optical switching engine (5) arranged sequentially along the optical path, wherein the path of the optical signal emitted from the transmitter (11) in the optical transceiver (1) is the optical path; The optical signal emitted from the transmitter (11) in the optical transceiver (1) is received by the grating assembly (2) and divided into multiple optical signals of different wavelengths; the optical signals of different wavelengths are transmitted to the phase grating (4) through the deflection element (3), wherein the deflection angle of the optical signals of different wavelengths is changed by the deflection element (3) so that the grating period corresponding to the optical signals of different wavelengths is consistent. The phase grating (4) divides each optical signal of different wavelengths into diffracted light of different orders. All diffracted light of different orders is reflected by the optical switching engine (5) and passes through the phase grating (4), the deflection element (3) and the grating assembly (2) in sequence. The diffracted light of different wavelengths of preset orders is received by the corresponding receiver (12) in the optical transceiver (1). Among them, diffracted light of the same order of different wavelengths converges.

2. The wavelength selective switching device with pre-offset angle adjustment according to claim 1, characterized in that, The deflection element (3) is a metasurface element, a wedge element, a mirror element or a grating element. The deflection element (3) is used to deflect the light signal passing through at different angles according to different wavelengths, thereby adjusting the incident angle of light signals of different wavelengths on the optical switching engine (5).

3. The wavelength selective switching device with pre-offset angle adjustment according to claim 1, characterized in that, The diffraction equation of the optical switching engine (5) is as follows: d(λ)sinθ out (λ)+d(λ)sinθ in (λ)=mλ; Where d(λ) is the equivalent phase grating period corresponding to the optical signal with wavelength λ, and θ out (λ) is the emission angle of the optical signal with wavelength λ from the optical switching engine (5), θ in (λ) is the incident angle of the optical signal with wavelength λ from the optical switching engine (5), and m is the diffraction order of the optical signal.

4. The wavelength selective switching device with pre-offset angle adjustment according to claim 3, characterized in that, The relationship between the incident and exit angles of the optical signal of the corresponding wavelength on the optical switching engine (5) and the distance between the transmitter (11) and the receiver (12) is: f(λ)|θ out(λ) -θ in(λ) |=H; Where f(λ) is the equivalent focal length of the optical signal with wavelength λ in the vertical direction, and θ out (λ) is the emission angle of the optical signal with wavelength λ from the optical switching engine (5), θ in (λ) is the incident angle of the optical signal with wavelength λ from the optical switching engine (5), and H is the height difference in the vertical direction between the receiving end (12) and the transmitting end (11) corresponding to the optical signal with wavelength λ.

5. The wavelength selective switching device with pre-offset angle adjustment according to claim 1, characterized in that, The deflection element (3) includes multiple preset regions. Each preset region is used to allow light signals of a corresponding wavelength to pass through both sides of the preset region, and to adjust the deflection angle of the light signals of the corresponding wavelength accordingly.

6. The wavelength selective switching device with pre-offset angle adjustment according to claim 5, characterized in that, The formula for the included angle between the two sides of the preset region is: |(n-1)θ1|=|θ inafter (λ1)-θ inbefore (λ1)|; Where n is the refractive index of the deflection element (3), λ1 is the wavelength, θ1 is the angle between the two sides of the preset region corresponding to the optical signal of wavelength λ1, and θ inafter (λ1) is the angle between the light signal with wavelength λ1 and the normal of the light switching engine (5) after passing through the deflection element (3), θ inbefore (λ1) is the angle between the normal of the optical signal with wavelength λ1 and the optical switching engine (5) when the optical signal has not passed through the deflection element (3).

7. The wavelength selective switching device with pre-offset angle adjustment according to claim 1, characterized in that, The wavelength selection switch device for pre-offset angle adjustment further includes a first dispersive lens group (61), a first switching lens group (71), a second switching lens group (72), and a second dispersive lens group (62), wherein: The first dispersive lens group (61) and the first switching lens group (71) are sequentially arranged between the optical transceiver end (1) and the grating assembly (2) along the optical path, and the second switching lens group (72) and the second dispersive lens group (62) are sequentially arranged between the grating assembly (2) and the phase grating (4) along the optical path.

8. The wavelength selective switching device with pre-offset angle adjustment according to claim 1, characterized in that, The wavelength selection switch device with pre-offset adjustment further includes a third dispersive lens group (63) and a third switching lens group (73); The third dispersive lens group (63) receives the light signal emitted from the transmitter (11) in the optical transceiver (1) and reflects the light signal to the third switching lens group (73). After passing through the third switching lens group (73), the light signal is incident on the grating assembly (2) and is divided into multiple light signals of different wavelengths by the grating assembly (2). The light signals of different wavelengths are reflected back to the third switching lens group (73) after passing through the third switching lens group (73). The multiple light signals of different wavelengths are received by the third dispersive lens group (63) and reflected by the third dispersive lens group (63) onto the phase grating (4). The phase grating (4) divides each light signal of different wavelengths into diffracted light of different orders. All diffracted light of different orders is reflected by the optical switching engine (5) and transmitted toward the optical transceiver (1). The diffracted light of different wavelengths of preset orders is received by the corresponding receiver (12) in the optical transceiver (1).

9. The wavelength selective switching device with pre-offset angle adjustment according to claim 8, characterized in that, The deflection element (3) is located in the optical path of the multiple optical signals of different wavelengths and is disposed between the optical switching engine (5) and the third dispersive lens group (63).

10. The wavelength selective switching device with pre-offset angle adjustment according to claim 8, characterized in that, The deflection element (3) is located in the optical path of the multiple optical signals of different wavelengths, and is disposed between the third dispersive lens group (63) and the third switching lens group (73) or between the third switching lens group (73) and the grating assembly (2).

11. The wavelength selective switching device with pre-offset angle adjustment according to claim 1, characterized in that, A first preprocessing unit (81) and a second preprocessing unit (82) are also provided between the optical transceiver (1) and the grating assembly (2); The first preprocessing unit (81) is located on the outgoing optical path of the transmitter (11) and is used to perform beam shaping on the optical signal emitted by the transmitter (11). The second preprocessing unit (82) is located on the receiving optical path of the receiving end (12) and is used to perform beam shaping on the optical signal directed to the receiving end (12).

12. The wavelength selective switching device with pre-offset angle adjustment according to claim 11, characterized in that, Both the first preprocessing unit (81) and the second preprocessing unit (82) include a beam shaping lens, which is used to shape the optical signal beam. Both the first preprocessing unit (81) and the second preprocessing unit (82) also include a polarization beam splitter element, which is used to perform polarization beam splitting processing on the optical signal.

13. A method of using a wavelength selective switch device with pre-offset angle adjustment, for application in the wavelength selective switch device with pre-offset angle adjustment as described in any one of claims 1-12, characterized in that, include: The optical signal emitted from the transmitter (11) in the optical transceiver (1) is received by the grating assembly (2) and divided into multiple optical signals of different wavelengths; The light signals of different wavelengths are transmitted to the phase grating (4) through the deflection element (3). The deflection angle of the light signals of different wavelengths is changed by the deflection element (3) so that the grating period corresponding to the light signals of different wavelengths is consistent. The phase grating (4) divides each optical signal of different wavelengths into diffracted light of different orders, wherein diffracted light of the same order in optical signals of different wavelengths converges. All diffracted light of different orders is reflected by the optical switching engine (5) and passes sequentially through the phase grating (4), the deflection element (3) and the grating assembly (2). Diffracted light of different wavelengths of preset orders is received by the corresponding receiver (12) in the optical transceiver (1).

14. The method of using the wavelength selective switch device with pre-offset angle adjustment according to claim 13, characterized in that, The deflection element (3) includes multiple preset regions. Changing the deflection angle of light signals of different wavelengths via the deflection element (3) specifically includes: The light signal of the corresponding wavelength passes through the two sides of the corresponding preset area, thereby adjusting the deflection angle of the light signal of the corresponding wavelength.

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