A superlens-based optical communication system

Abstract

This application provides a superlens-based optical communication system, comprising: a superlens; an optical communication element; and a distance between the superlens and the optical communication element along the optical path propagation direction greater than or equal to one focal length of the superlens; the superlens is used to modulate the received light beam and output the modulated light beam. This application enables the coupling operation of the light beam in an optical communication system using a single superlens, improving the coupling efficiency of the light beam, increasing the light energy utilization rate, and reducing the production cost and size of the optical communication system.

Description

[0001] This application claims priority to Chinese Patent Application No. 202422190212.2, filed on September 6, 2024, entitled "An Optical Communication System Based on a Superlens", the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of optics, specifically to an optical communication system based on a superlens. Background Technology

[0003] In optical communication systems, operations such as focusing, collimating, expanding, combining / splitting, and coupling of light beams are typically required, necessitating the use of numerous aspherical lenses made of glass or silicon. For example, when coupling a laser beam into an optical fiber, a biconvex aspherical lens made of glass is commonly used.

[0004] Since the two curved surfaces of an aspherical lens are not standard spheres, their design requires controlling the surface shape using parameters such as the radius of curvature, conic coefficient, and polynomial coefficients that control the degree of surface concavity. However, using high-order polynomial coefficients to precisely define the surface shape significantly increases the complexity and fabrication difficulty of the aspherical lens. Therefore, to ensure fabrication feasibility, the order of the polynomial coefficients is often limited, or even only the radius of curvature and conic coefficient are used to define the surface shape of the aspherical lens. This makes it difficult to achieve optimal design parameters for the aspherical lens, resulting in low coupling efficiency. Furthermore, aspherical lenses made of glass or silicon are not only expensive to manufacture but also have a large thickness, leading to high production costs, and the optical communication system in which they are located is also large in size. Utility Model Content

[0005] One objective of this application is to provide a superlens-based optical communication system. The superlens-based optical communication system provided in this application enables beam coupling operations within the system using a single superlens, improving beam coupling efficiency while also reducing the production cost and size of the optical communication system.

[0006] According to one aspect of the embodiments of this application, a superlens-based optical communication system is disclosed, the optical communication system comprising: a superlens; and an optical communication element;

[0007] Along the direction of light propagation, the distance between the superlens and the optical communication element is greater than or equal to one focal length of the superlens;

[0008] The superlens is used to modulate the received light beam and output the modulated light beam.

[0009] In an exemplary embodiment of this application, the phase of the superlens satisfies:

[0010]

[0011] in, Let M be the phase of the superlens, M be the diffraction order, N be the phase order, and A be the phase of the superlens. i Let ρ be the phase coefficients of each term, and ρ be the polar coordinates of the two-dimensional plane in which the superlens is located.

[0012] In an exemplary embodiment of this application, the optical communication element is a light source, and the superlens is disposed on the light-emitting side of the light source;

[0013] The superlens is used to receive the light beam emitted by the light source and to collimate the light beam emitted by the light source; or, the superlens is used to receive the light beam emitted by the light source and to converge the light beam emitted by the light source.

[0014] In an exemplary embodiment of this application, the optical communication element is the output end of an optical fiber, and the superlens is disposed downstream of the output end along the optical path propagation direction;

[0015] The superlens is used to receive the light beam output from the output terminal and to converge the light beam output from the output terminal.

[0016] In an exemplary embodiment of this application, the optical communication element includes: a light source; and a receiving end of an optical fiber;

[0017] The superlens is used to receive and modulate the light beam emitted by the light source to converge the emitted light beam to the receiving end of the optical fiber.

[0018] In an exemplary embodiment of this application, the optical communication element includes: a light source; and an intermediate optical element for processing the light beam;

[0019] The superlens is used to receive and collimate the light beam emitted by the light source, so as to project the collimated light beam onto the intermediate optical element.

[0020] In an exemplary embodiment of this application, the intermediate optical element includes: a first color filter; an isolator; a second color filter; and a focusing lens;

[0021] The first color filter is used to filter the aligned light beam; the isolator is used to block reflected light; the second color filter is used to perform secondary filtering on the light beam that has passed through the isolator; and the focusing lens is used to converge the light beam that has been filtered twice by the second color filter.

[0022] In an exemplary embodiment of this application, the optical communication element includes: the output end of an optical fiber; and a photoelectric sensor;

[0023] The superlens is used to receive and modulate the light beam output from the output terminal to converge the light beam output from the output terminal to the photoelectric sensor; the photoelectric sensor is used to perform photoelectric processing on the light beam output from the output terminal.

[0024] In an exemplary embodiment of this application, the superlens includes: a first superlens; and a second superlens;

[0025] The optical communication element includes: a light source; an output end of an optical fiber; a receiving end of an optical fiber; and a photoelectric sensor.

[0026] The first superlens is used to focus the light beam emitted by the light source to the receiving end, and the optical fiber conducts the light beam received by the receiving end to the output end and outputs it;

[0027] The second superlens is used to focus the light beam output from the output end onto the photoelectric sensor.

[0028] In an exemplary embodiment of this application, the superlens includes: a first superlens; a second superlens; and a third superlens;

[0029] The optical communication element includes: a light source; an output end of an optical fiber; an intermediate optical element for processing the light beam; a receiving end of an optical fiber; and a photoelectric sensor.

[0030] The first superlens is used to collimate the light beam emitted by the light source and project the collimated light beam onto the intermediate optical element;

[0031] The second superlens is used to converge the light beam processed by the intermediate optical element to the receiving end, and the optical fiber conducts the light beam received by the receiving end to the output end and outputs it;

[0032] The third superlens is used to focus the light beam output from the output end onto the photoelectric sensor.

[0033] The superlens-based optical communication system provided in this application includes: a superlens; an optical communication element; and a distance between the superlens and the optical communication element along the optical path propagation direction greater than or equal to one focal length of the superlens; the superlens is used to modulate the received light beam and output the modulated light beam. This application enables the coupling operation of the light beam in an optical communication system through a single superlens, improving the coupling efficiency of the light beam, increasing the light energy utilization rate, and reducing the production cost and size of the optical communication system.

[0034] Other features and advantages of this application will become apparent from the following detailed description, or may be learned in part from practice of this application.

[0035] It should be understood that the above general description and the following detailed description are merely exemplary and do not limit this application. Attached Figure Description

[0036] The above and other objectives, features and advantages of this application will become more apparent from a detailed description of exemplary embodiments thereof with reference to the accompanying drawings.

[0037] Figure 1 A schematic diagram of the structure of a superlens provided in an embodiment of this application is shown.

[0038] Figure 2 A partial schematic diagram of an optical communication system provided in one embodiment of this application is shown.

[0039] Figure 3 A partial schematic diagram of an optical communication system provided in one embodiment of this application is shown.

[0040] Figure 4 A partial schematic diagram of an optical communication system provided in one embodiment of this application is shown.

[0041] Figure 5 A partial schematic diagram of an optical communication system provided in one embodiment of this application is shown.

[0042] Figure 6 This paper shows a schematic diagram of the mode field intensity of the two-dimensional plane where the receiving end of the optical fiber is located in the optical communication system provided in Embodiment 1 of this application.

[0043] Figure 7 A schematic diagram of the mode field intensity of the two-dimensional plane where the receiving end of the optical fiber is located in the optical communication system based on an aspherical lens provided in the comparative example of Embodiment 1 is shown.

[0044] Figure 8 A schematic diagram showing the specific parameters of a portion of the structure of the optical communication system provided in Embodiment 2 of this application is shown.

[0045] Figure label:

[0046] 1-Superlens; 11-Substrate; 12-Micro / nano structure; 2-Light source; 31-Receiver; 32-Output; 4-Photoelectric sensor; 51-First color filter; 52-Second color filter; 6-Isolator; 7-Focusing lens. Detailed Implementation

[0047] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, they are provided to make the description of this application more comprehensive and complete, and to fully convey the concept of the exemplary embodiments to those skilled in the art. The drawings are merely illustrative of this application and are not necessarily drawn to scale. The same reference numerals in the drawings denote the same or similar parts, and therefore repeated descriptions of them will be omitted.

[0048] Furthermore, the described features, structures, or characteristics can be combined in any suitable manner in one or more exemplary embodiments. Numerous specific details are provided in the following description to give a full understanding of exemplary embodiments of this application. However, those skilled in the art will recognize that the technical solutions of this application can be practiced with one or more of the specific details omitted, or other methods, components, steps, etc., can be employed. In other instances, well-known structures, methods, implementations, or operations are not shown or described in detail to avoid obscuring various aspects of this application.

[0049] In existing technologies, optical communication systems involve operations such as focusing, collimating, expanding, combining / splitting, and coupling of light beams to achieve optical signal propagation. Current technologies typically use aspherical lenses made of glass or silicon to modulate the beam. However, the design of aspherical lenses requires parameters such as radius of curvature, conic coefficient, and polynomial coefficients controlling the degree of surface concavity to control the surface shape. Precisely defining the surface shape of an aspherical lens necessitates the use of high-order polynomial coefficients, significantly increasing the complexity and fabrication difficulty. Therefore, to ensure fabrication feasibility, the order of the polynomial coefficients is often limited, or even omitted entirely, using only the radius of curvature and conic coefficient to define the surface shape. This makes it difficult to achieve optimal design parameters for the aspherical lens, resulting in low beam coupling efficiency and low light energy utilization. Furthermore, glass or silicon aspherical lenses are expensive to manufacture and relatively thick, hindering the reduction of production costs for optical communication systems and impeding miniaturization.

[0050] To overcome the aforementioned deficiencies in related technologies, this application provides an optical communication system based on a superlens. The optical communication system provided by this application enables beam coupling operations within the optical communication system using a single superlens, improving beam coupling efficiency, increasing light energy utilization, and reducing the production cost and size of the optical communication system.

[0051] This application provides an optical communication system based on a superlens, which includes a superlens 1 and an optical communication element. For example... Figure 1 As shown, Figure 1 A schematic diagram of a superlens provided in an embodiment of this application is shown. The superlens 1 includes a substrate 11 and micro / nano structures 12 disposed on the substrate 11. The micro / nano structures 12 are subwavelength structures. The superlens 1 mainly provides corresponding phases at various locations on its micro / nano structures 12 by configuring parameters such as material, cross-sectional size, height, and arrangement period. This applies different phase abrupt changes to the received light beam, thereby giving each position on the superlens 1 a certain phase gradient, thus modulating the light beam received at different positions on the superlens 1.

[0052] In the embodiments of this application, along the optical path propagation direction, the distance between the superlens 1 and the optical communication element is greater than or equal to one focal length of the superlens 1. The superlens 1 is used to modulate the received light beam and output the modulated light beam.

[0053] In one embodiment, the phase of the superlens 1 satisfies:

[0054]

[0055] in, Let M be the phase of superlens 1, M be the diffraction order, N be the phase order, and A be the phase of superlens 1. i Let ρ be the phase coefficients, and ρ be the distance from any position in the two-dimensional plane containing superlens 1 to the center of superlens 1.

[0056] It should be noted that, in the embodiments of this application, the phase of the superlens 1 is expressed by the above phase formula. When the phase of the superlens 1 is optimized in the future, the aberration of the superlens 1 can be reduced better, and the modulation capability of the superlens 1 on the light beam can be improved.

[0057] In one embodiment, the phase distribution of the superlens 1 can be optimized based on the phase formula of the superlens 1 using optical simulation design software (such as Zemax simulation software) to obtain the target phase of the superlens 1, and the micro-nano structure 12 on the superlens 1 can be filled according to the target phase.

[0058] In one embodiment, the micro / nano structure 12 can be disposed on the surface of the substrate 11 facing away from the incident light, thereby reducing the incident angle of the incident light entering the superlens 1.

[0059] In another embodiment, the micro / nano structure 12 can also be disposed on the surface of the substrate 11 facing the incident light, so that the substrate 11 has a protective function.

[0060] In the optical communication system provided in this application, the superlens 1 can be used to focus the received light beam, thereby realizing the coupling-in and coupling-out operations in the optical communication system. That is, the phase of the superlens 1 is the focusing phase, which is used to converge the light beam received by the superlens 1. It should be noted that the coupling-in of the light beam mentioned in the embodiments of this application refers to coupling an external light beam into the optical fiber through the superlens 1; the coupling-out of the light beam refers to coupling the light beam propagating in the optical fiber out to the external environment through the superlens 1. Optical fiber is short for optical waveguide fiber, which is a fiber made of glass or plastic and can be used as a tool for light beam transmission. In the embodiments of this application, the end of the optical fiber used to receive the light beam is called the receiving end 31, and the end of the optical fiber used to output the light beam propagated in the optical fiber is called the output end 32. It can be understood that the receiving end 31 and the output end 32 of the optical fiber mentioned in this application can be on the same optical fiber or on different optical fibers. As long as they functionally meet the requirements of receiving and outputting, they can be called the receiving end 31 and the output end 32 of the optical fiber.

[0061] In one embodiment, the optical communication element is a light source 2, such as... Figure 2 As shown, Figure 2 A partial schematic diagram of an optical communication system provided in one embodiment of this application is shown. In this case, a superlens 1 is disposed on the light-emitting side of the light source 2, and the superlens 1 is used to converge the light beam emitted by the light source 2. It is easy to understand that, in this case, the distance between the superlens 1 and the light source 2 is greater than one focal length of the superlens 1.

[0062] In one embodiment, the optical communication element is a light source 2, such as... Figure 3 As shown, Figure 3 A partial schematic diagram of an optical communication system provided in one embodiment of this application is shown. In this case, a superlens 1 is disposed on the light-emitting side of the light source 2, and the superlens 1 is used to collimate the light beam emitted by the light source 2. It is easy to understand that, in this case, the distance between the superlens 1 and the light source 2 is equal to one focal length of the superlens 1.

[0063] It should be noted that "the distance is equal to one focal length" here does not mean that they are completely equal in a strict sense. In fact, it means that the distance between the superlens 1 and the light source 2 is within a reasonable tolerance range of one focal length.

[0064] In one embodiment, the optical communication element is the output end 32 of an optical fiber, such as... Figure 5 As shown, Figure 5A partial schematic diagram of an optical communication system provided in an embodiment of this application is shown. In this case, the superlens 1 is disposed downstream of the output end 32 of the optical fiber along the optical path propagation direction. That is, the superlens 1 is used to couple the light beam output from the output end 32 of the optical fiber, and to converge the light beam output from the output end 32. It is easy to understand that in this case, the distance between the superlens 1 and the output end 32 is greater than one focal length of the superlens 1.

[0065] In one embodiment, the optical communication element includes: a light source 2; and a receiving end 31 of an optical fiber. For example... Figure 2 As shown, the superlens 1 is positioned upstream of the receiving end 31 of the optical fiber along the optical path propagation direction. That is, the superlens 1 is used to couple the light beam emitted by the light source 2 into the optical fiber. After receiving the light beam, the optical fiber guides the light beam to the next optical element in the optical communication system. In this case, there are no other optical elements between the superlens 1 and the receiving end 31, and the light beam emitted by the light source 2 is converged to the receiving end 31 by the superlens 1.

[0066] In one embodiment, the optical communication element includes: a light source 2; and an intermediate element for modulating the light beam.

[0067] At this time, the superlens 1 is used to collimate the light beam emitted by the light source 2. That is, the light beam emitted by the light source 2 is received and collimated by the superlens 1, and then emitted with a small divergence angle. After propagating a certain distance, it reaches the intermediate optical element, which then processes the light beam. At this time, the phase of the superlens 1 is the collimation phase, which is used to collimate the light beam received by the superlens 1.

[0068] Furthermore, the intermediate optical element used to process the light beam is a first color filter 51, which is used to filter the aligned light beam.

[0069] Specifically, in optical communication systems, when a light beam propagates through an optical fiber, it typically needs to be processed to suit different scenarios. For example... Figure 4 As shown, Figure 4 A partial schematic diagram of an optical communication system provided in an embodiment of this application is shown. This optical communication system is applicable to wavelength division multiplexing (WDM) or signal separation scenarios. WDM is a technique that combines two or more beams of different operating wavelengths together and transmits them through a single optical fiber; signal separation is a technique that separates a composite optical signal containing beams of multiple different operating wavelengths. In this case, by adding a first color filter 51 during beam propagation, the first color filter 51 can filter the received beam, retaining only the beam that conforms to the target operating wavelength, thereby achieving wavelength division multiplexing or signal separation of the beam.

[0070] When the optical communication system in this embodiment is used for wavelength division multiplexing of a light beam, the superlens 1 collimates the light beam emitted by the light source 2 and projects it onto the first color filter 51. The first color filter 51 filters the light beam to reduce noise interference in the light beam. The filtered light beam is then focused to the receiving end 31 of the next optical fiber by the focusing lens 7 located downstream of the first color filter 51 along the optical path propagation direction. The light beam is then guided by the next optical fiber to the multiplexer used to combine light beams of different working wavelengths, thereby realizing wavelength division multiplexing.

[0071] When the optical communication system in this embodiment is used for signal separation of a light beam, the light beam is actually a composite optical signal containing multiple light beams with different operating wavelengths. That is, the micro-nano structure 12 on the superlens 1 can provide different phase transitions for light beams with different operating wavelengths, thereby collimating all light beams with different operating wavelengths and projecting them onto the first color filter 51. The first color filter 51 filters the light beam it receives, retaining only the light beam that actually conforms to the target operating wavelength. The focusing lens 7, which is set downstream of the first color filter 51 along the optical path propagation direction, focuses this light beam that conforms to the target operating wavelength to the receiving end 31 of the next optical fiber, thereby realizing signal separation of the light beam.

[0072] Furthermore, such as Figure 4 As shown, along the optical path propagation direction, the intermediate optical elements also sequentially include: an isolator 6; a second color filter 52; and a focusing lens 7. The isolator 6 blocks reflected light, preventing interference and noise caused by reflected light from other optical elements (such as the focusing lens 7) during beam propagation, thereby reducing beam distortion. The second color filter 52 performs secondary filtering on the beam filtered by the first color filter 51; the focusing lens 7 converges the beam after secondary filtering by the second color filter 52. In one embodiment, the focusing lens 7 can converge the received beam to the receiving end 31 of the optical fiber.

[0073] In this case, the superlens 1, the first color filter 51, the isolator 6, the second color filter 52, and the focusing lens 7 can be arranged on the same optical axis.

[0074] It should be noted that the working wavelength range of the light beam that can be transmitted by the first color filter 51 and the second color filter 52 is the same. In this case, by performing two filtering processes on the light beam, the filtering accuracy of the light beam can be improved, thereby making the filtered light beam more in line with the target working wavelength.

[0075] In one embodiment, the focusing lens 7 is a conventional refractive lens, such as... Figure 4 As shown, Figure 4 The focusing lens 7 in the image is a traditional refractive lens.

[0076] In one embodiment, the focusing lens 7 can also be a superlens 1 as described in the above embodiment. That is, in this case, the optical communication system includes two superlenses 1. However, it should be noted that the two superlenses 1 have different functions. The first superlens 1 along the optical path propagation direction is used to collimate the light beam emitted by the light source 2 so that the light beam can propagate to the first color filter 51 with a small divergence angle. The second superlens 1 along the optical path propagation direction is used to converge the light beam that has passed through the second color filter 52, so that the light beam can be converged to the receiving end 31 of the optical fiber.

[0077] In one embodiment, the optical communication element includes: an output end 32 of an optical fiber; and a photoelectric sensor 4. For example... Figure 5 As shown, Figure 5 A partial schematic diagram of an optical communication system provided in an embodiment of this application is shown. In this case, the superlens 1 is positioned downstream of the output end 32 of the optical fiber along the optical path propagation direction. That is, the superlens 1 is used to couple out the light beam guided by the optical fiber, so that the light beam can be accurately propagated to the photoelectric sensor 4 positioned downstream of the superlens 1 through modulation by the superlens 1. At this time, there are no other optical elements between the superlens 1 and the output end 32. The light beam output from the output end 32 directly illuminates the superlens 1, is modulated by the superlens 1, and is output to the photoelectric sensor 4. After receiving this light beam, the photoelectric sensor 4 performs photoelectric processing on the light beam. The photoelectric sensor 4 is an optical element that uses the photoelectric effect to convert light signals into electrical signals. It can sense the intensity, color, wavelength, and other information of the received light beam, convert the received light beam into an electrical signal, and perform subsequent processing and utilization.

[0078] In one embodiment, the superlens 1 includes a first superlens and a second superlens, and the optical communication element includes: a light source 2; an output end 32 of an optical fiber; a receiving end 31 of an optical fiber; and a photoelectric sensor 4. It should be noted that both the first superlens and the second superlens are types of superlens 1, and "first" and "second" are only used to distinguish between the two superlenses 1.

[0079] In other words, in this configuration, the first superlens is positioned upstream of the receiving end 31 of the optical fiber, and the second superlens is positioned downstream of the output end 32 of the optical fiber. The first and second superlenses together complete the coupling-in and coupling-out operations in the optical communication system. The first superlens is used to focus the light beam emitted by the light source 2 onto the receiving end 31 of the optical fiber. After the light beam is transmitted a certain distance by the optical fiber, it is output from the output end 32 of the optical fiber. The second superlens is used to focus the light beam output from the output end 32 onto the photoelectric sensor 4.

[0080] It should be noted that the receiving end 31 and the output end 32 can be located in the same optical fiber. That is, the light beam is coupled into the optical fiber by the first superlens located upstream of the receiving end 31, the light beam is guided by the optical fiber and output from the output end 32, and then received and modulated by the second superlens located downstream of the output end 32. Alternatively, the receiving end 31 and the output end 32 can be located in different optical fibers. That is, the light beam is coupled into the optical fiber by the first superlens located upstream of the receiving end 31, the optical fiber guides the light beam to the optical element set in the propagation path of the optical fiber, the optical element processes the light beam, and then guides it through another optical fiber to its corresponding output end 32, and then outputs it through the output end 32. In this case, the receiving end 31 and the output end 32 are located in two different optical fibers.

[0081] It should be noted that, in this case where the first and second superlenses are used to focus the light beams emitted by different optical communication elements, there are no other optical elements between the first superlens located upstream of the receiver 31 and the receiver 31, and there are no other optical elements between the second superlens located downstream of the output end 32 and the output end 32. In this embodiment, the coupling operation of the light beam in the optical communication system is achieved by the two superlenses, which improves the coupling efficiency of the light beam while reducing the production cost and size of the optical communication system.

[0082] In one embodiment, the superlens 1 includes a first superlens, a second superlens, and a third superlens. The optical communication element includes: a light source 2; an output end 32 of an optical fiber; an intermediate optical element for processing the light beam; a light receiving end 31; and a photoelectric sensor 4. It should be noted that the first superlens, the second superlens, and the third superlens are all types of superlens 1, and the terms "first," "second," and "third" are only used to distinguish the three superlenses 1.

[0083] In this configuration, the first superlens is positioned upstream of the intermediate optical element, the second superlens downstream of the intermediate optical element, and the third superlens downstream of the output end 32. The first, second, and third superlenses collectively perform collimation, coupling-in, and coupling-out operations in the optical communication system. The first superlens collimates the light beam emitted by the light source 2 and projects the collimated beam onto the intermediate optical element. The intermediate optical element processes the received beam and projects it onto the second superlens. The second superlens converges the beam processed by the intermediate optical element to the receiving end 31 of the optical fiber. After being propagated a distance by the optical fiber, the beam is output from the output end 32 of the optical fiber. The third superlens converges the beam output from the output end 32 to the photoelectric sensor 4.

[0084] It should be noted that the receiver 31 and the output 32 can be located on the same optical fiber; or, the receiver 31 and the output 32 can be located on different optical fibers.

[0085] Example 1

[0086] The partial structure of the optical communication system provided in Example 1 is as follows: Figure 2 As shown, the superlens 1 is used to converge the light beam emitted by the light source 2, so that the light beam emitted by the light source 2 can be coupled into the receiver 31.

[0087] In this embodiment, the light source 2 is a laser with a working wavelength of 1550nm, the substrate 11 of the superlens 1 has a thickness of 0.5mm, the refractive index of the substrate 11 material is 3.46, the divergence angle of the Gaussian beam generated by the laser is defined as 35°×55° (horizontal direction×vertical direction) at half maximum width and height, and the mode field radius of the receiving end 31 of the optical fiber is 4.6μm.

[0088] After optimization, the final determined superlens intercept (i.e., the distance from the laser to the incident surface of superlens 1) is 0.59758 mm, the effective radius of superlens 1 is 0.74016 mm, the phase order of superlens 1 is N = 7, and the phase coefficients are as follows:

[0089] A1 = -2962.1796;

[0090] A2 = 879.09444;

[0091] A3 = -601.21780;

[0092] A4 = 317.74875;

[0093] A5 = 154.1304;

[0094] A6 = 32.3308;

[0095] A7 = -1.7372;

[0096] The final measured coupling efficiency was 90.6474%. (See also...) Figure 6 , Figure 6 This paper shows a schematic diagram of the mode field intensity of the two-dimensional plane where the receiving end of the optical fiber is located in the optical communication system provided in Embodiment 1 of this application.

[0097] In comparison, a glass-based biconvex aspherical lens with a refractive index of 1.81 was used to achieve the same focusing function under the same preconditions. After optimization, the final determined aspherical lens intercept (i.e., the distance from the laser to the vertex of the incident surface of the aspherical lens) was 0.80662 mm, and the thickness (i.e., the distance between the vertices of the incident and exit surfaces) was 1.42 mm. The effective radius of the incident surface was 0.67 mm, the radius of curvature was 1.6554 mm, the conicity coefficient was -10.872, and the polynomial coefficient of the surface concavity was:

[0098] The fourth-order term = -0.0694;

[0099] The 6th-order term = 0.0807;

[0100] The 8th-order term = -0.0425;

[0101] The 10th-order term = 0.0078;

[0102] The effective radius of the light-emitting surface is 0.895 mm, the radius of curvature is -1.1342 mm, the conicity coefficient is -0.3496, and the polynomial coefficient of the surface concavity is:

[0103] The fourth-order term = 0.0649;

[0104] The 6th-order term = 0.0131;

[0105] The 8th-order term = 0.0019;

[0106] The 10th-order term = 0.0064;

[0107] The final measured coupling efficiency of this aspherical lens was 33.2259%. (See also...) Figure 7 , Figure 7 A schematic diagram of the mode field intensity of the two-dimensional plane where the receiving end of the optical fiber is located in the optical communication system based on an aspherical lens provided in the comparative example of Embodiment 1 is shown.

[0108] As can be seen from the above, the coupling efficiency of the superlens 1 provided in Embodiment 1 is much higher than that of the coupling efficiency of the beam using an aspherical lens in the traditional scheme. Furthermore, since the superlens 1 can be manufactured using semiconductor technology, the cost of a single superlens 1 is low during mass production, which can further reduce the production cost of the optical communication system.

[0109] Example 2

[0110] The partial structure of the optical communication system provided in Example 2 is as follows: Figure 5 As shown, the superlens 1 is used to converge the light beam output from the output end 32 of the optical fiber, so that the light beam can be coupled out of the optical fiber and converged onto the photoelectric sensor 4. In this embodiment, the focal length of the superlens 1 is calculated according to the Gaussian formula. Subsequently, this focal length is used as an initial value to optimize the phase of the superlens 1, thereby designing the required phase distribution of the superlens 1. The Gaussian formula can be specifically expressed as:

[0111]

[0112] l2 = f(1 + m);

[0113] Where f is the focal length, l1 is the object distance (i.e., the distance from the output end 32 to the light-incident surface of the superlens 1), l2 is the image distance (i.e., the distance from the light-out surface of the superlens 1 to the light-incident surface of the photoelectric sensor 4), and m is the transverse magnification.

[0114] In this embodiment, the operating wavelength of the light beam emitted by the light source 2 is 1577nm, the distance from the plane of the output end 32 to the light incident surface of the photoelectric sensor 4 is 4.88mm, and the thickness of the substrate 11 of the superlens 1 is 0.5mm. In the optical system composed of the output end 32, the superlens 1, and the photoelectric sensor 4, the object-to-image ratio is 4×, wherein the numerical aperture of the output end 32 of the optical fiber is 0.2.

[0115] Based on the above data, and according to the Gaussian formula, the initial focal length of superlens 1 can be calculated to be 0.768 mm, the initial object distance to be 3.44 mm, and the initial image distance to be 0.86 mm. Simultaneously, the phase order of superlens 1 is set to N = 5. Under this initial focal length, the calculated initial phase coefficient is:

[0116] A1 = -2932.289270778921;

[0117] A2 = 1534.25292196328;

[0118] A3 = -1472.05427459534;

[0119] A4 = 1287.16461905233;

[0120] A5 = -601.308899188362;

[0121] Since the substrate of the superlens 1 affects the incident angle of the light beam onto the micro / nano structure surface (i.e., the plane on which the micro / nano structure is set), the phase of the superlens 1 designed according to the above phase coefficients fails to accurately achieve an object-to-image ratio of 4×. Therefore, it is necessary to optimize the initial object distance, initial image distance, and initial phase coefficients. The optimized phase coefficients are as follows:

[0122] A1 = -2801.710164119107;

[0123] A2 = 717.1663743642454;

[0124] A3 = -425.1839677805656;

[0125] A4 = 255.5843819595677;

[0126] A5 = -90.91879731834548;

[0127] The optimized object distance is 3.411 mm, and the image distance is 0.889 mm. For example... Figure 8 As shown, Figure 8 A schematic diagram showing specific parameters of a portion of the structure of the optical communication system provided in Embodiment 2 of this application is shown. See also Figure 8 The aperture of the superlens 1 is 1.9 mm, and the effective area diameter is 1.6 mm.

[0128] Example 3

[0129] The partial structure of the optical communication system provided in Example 3 is as follows: Figure 4 As shown, the superlens 1 is used to collimate the received light beam, so that the collimated light beam can travel a distance with a small divergence angle to reach the first color filter 51, and after passing through the isolator 6 and the second color filter 52, it is focused by the focusing lens 7 onto the receiving end 31 of the optical fiber.

[0130] In this embodiment, the operating wavelength of the light beam is 1577 nm, the numerical aperture of the object side is 0.5 mm, the aperture of the superlens 1 is 0.6 mm, the thickness of the substrate 11 of the superlens 1 is 0.5 mm, the refractive index of the substrate 11 material is 3.48, the divergence angle of the laser used to emit the light beam, defined by full width at half maximum (FWHM) as 17.8° × 22.9° (horizontal × vertical), and the mode field radius of the receiving end 31 of the optical fiber is 5.2 μm.

[0131] First, the phase order N of superlens 1 is set to 12. Using the above parameters in the Zemax simulation software, the initial phase coefficients are obtained as follows:

[0132] A1 = -6558.46;

[0133] A2 = 1.009E + 04;

[0134] A3 = -1.223E + 04;

[0135] A4 = -0.02;

[0136] A5 = -0.312;

[0137] A6 = 5.064;

[0138] A7 = 338.557;

[0139] A8 = 1.122E + 04;

[0140] A9 = 3.931E + 05;

[0141] A 10 =1.36E+07;

[0142] A 11=7.133E+08;

[0143] A 12 =2.523E+10;

[0144] Designing such in Zemax simulation software Figure 5 The optical system shown has its first and second color filters set to transmittance of 93.3%. After appropriate optimization, the resulting phase order is:

[0145] A1 = -6463.617;

[0146] A2 = 1.071E + 04;

[0147] A3 = -4952.732;

[0148] A4 = -1.081E+06;

[0149] A5 = -2.111E + 07;

[0150] A6 = -4.419E+08;

[0151] A7 = -1.027E + 10;

[0152] A8 = 3.984E + 11;

[0153] A9 = 5.269E + 12;

[0154] A 10 = -4.5E+13;

[0155] A 11 = -3.576E+15;

[0156] A 12 =3.65E+16;

[0157] The final optimized distance from the incident surface of the superlens 1 to the exit surface of the laser is 0.164 mm, and the measured coupling efficiency is 85.1687%.

[0158] Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the utility models disclosed herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this application are indicated by the appended claims.

Claims

1. An optical communication system based on a superlens, characterized in that, The optical communication system includes: a superlens; and optical communication elements. Along the direction of light propagation, the distance between the superlens and the optical communication element is greater than or equal to one focal length of the superlens; The superlens is used to modulate the received light beam and output the modulated light beam.

2. The optical communication system according to claim 1, characterized in that, The phase of the superlens satisfies: in, Let M be the phase of the superlens, M be the diffraction order, N be the phase order, and A be the phase of the superlens. i Let ρ be the phase coefficients of each term, and ρ be the polar coordinates of the two-dimensional plane in which the superlens is located.

3. The optical communication system according to claim 1, characterized in that, The optical communication element is a light source, and the superlens is disposed on the light-emitting side of the light source; The superlens is used to receive the light beam emitted by the light source and to collimate the light beam emitted by the light source; or, the superlens is used to receive the light beam emitted by the light source and to converge the light beam emitted by the light source.

4. The optical communication system according to claim 1, characterized in that, The optical communication element is the output end of an optical fiber, and the superlens is disposed downstream of the output end along the optical path propagation direction; The superlens is used to receive the light beam output from the output terminal and to converge the light beam output from the output terminal.

5. The optical communication system according to claim 1, characterized in that, The optical communication element includes: a light source; and a receiving end of an optical fiber. The superlens is used to receive and modulate the light beam emitted by the light source to converge the emitted light beam to the receiving end of the optical fiber.

6. The optical communication system according to claim 1, characterized in that, The optical communication element includes: a light source; and intermediate optical elements for processing the light beam. The superlens is used to receive and collimate the light beam emitted by the light source, so as to project the collimated light beam onto the intermediate optical element.

7. The optical communication system according to claim 6, characterized in that, The intermediate optical element includes: a first color filter; an isolator; a second color filter; and a focusing lens; The first color filter is used to filter the aligned light beam; the isolator is used to block reflected light; the second color filter is used to perform secondary filtering on the light beam that has passed through the isolator; and the focusing lens is used to converge the light beam that has been filtered twice by the second color filter.

8. The optical communication system according to claim 1, characterized in that, The optical communication element includes: the output end of an optical fiber; and a photoelectric sensor. The superlens is used to receive and modulate the light beam output from the output terminal to converge the light beam output from the output terminal to the photoelectric sensor; the photoelectric sensor is used to perform photoelectric processing on the light beam output from the output terminal.

9. The optical communication system according to claim 1, characterized in that, The superlens includes: a first superlens; a second superlens; The optical communication element includes: a light source; an output end of an optical fiber; a receiving end of an optical fiber; and a photoelectric sensor. The first superlens is used to focus the light beam emitted by the light source to the receiving end, and the optical fiber conducts the light beam received by the receiving end to the output end and outputs it; The second superlens is used to focus the light beam output from the output end onto the photoelectric sensor.

10. The optical communication system according to claim 1, characterized in that, The superlens includes: a first superlens; a second superlens; and a third superlens; The optical communication element includes: a light source; an output end of an optical fiber; an intermediate optical element for processing the light beam; a receiving end of an optical fiber; and a photoelectric sensor. The first superlens is used to collimate the light beam emitted by the light source and project the collimated light beam onto the intermediate optical element; The second superlens is used to converge the light beam processed by the intermediate optical element to the receiving end, and the optical fiber conducts the light beam received by the receiving end to the output end and outputs it; The third superlens is used to focus the light beam output from the output end onto the photoelectric sensor.

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