Waveguide, beam steering device, beam steering method and manufacturing method

Abstract

The present disclosure provides a waveguide, comprising: a rectangular parallelepiped metal shell having an opening on one side thereof; a slow-wave medium contained in the metal shell; feeding probes located at both ends of the metal shell, respectively, and inserted into the slow-wave medium through the metal shell; a slot plate comprising a plurality of slots covering the opening of the metal shell; a plurality of diodes and a plurality of photodetectors arranged on the slot plate, wherein the plurality of diodes, the plurality of photodetectors, and the plurality of slots correspond to each other, each diode spanning a corresponding slot, and each diode having a cathode electrically connected to the metal shell and a cathode electrically connected to a corresponding photodetector. The present disclosure also relates to a beam steering device comprising the waveguide, a beam steering method applied to the beam steering device, and a method for manufacturing a photodetector, wherein the photodetector can be applied to the waveguide.

Description

Technical Field

[0001] The present disclosure relates to the field of reconfigurable antennas, and in particular, to a waveguide and a beam steering device comprising the waveguide, and also to a beam steering method applicable to the beam steering device, and a method for manufacturing a photodetector. Background Art

[0002] Antennas play a critical role in wireless communication systems, and their characteristics can even directly determine the performance of the entire wireless communication system. With the advancement of technology, the demand for antenna performance is becoming increasingly stringent. In addition to high requirements for traditional indicators such as gain and polarization, antennas are often required to have low profiles, light weight, and conformability. The concept of holographic antennas originates from the principles of optical holography. The principle is to form an interference surface by interfering a target wave with a reference wave, and then invert the interference surface by illuminating the reference wave to obtain the target wave. The emergence of metamaterials has made it possible to realize holographic antennas in the microwave band. As high-gain antennas, holographic antennas simultaneously meet the requirements of low profile, light weight, simple processing, low cost, and conformability, and therefore have great development potential.

[0003] Furthermore, a key aspect of modern antennas is reconfigurability, which can significantly improve antenna reuse and reduce the cost and complexity of antenna systems. For example, if a holographic antenna incorporates reconfigurable units, a single holographic surface could enable multiple functions, such as beam scanning, multi-beam synthesis, and polarization reconfiguration, offering enormous potential for application.

[0004] However, traditional holographic antennas mostly use square or circular metal patch elements. Once the structure is fixed, it cannot be changed, making it impossible to achieve reconfiguration. In addition, the large number of elements in holographic antennas, in some cases up to hundreds or even thousands, makes it very difficult to dynamically control each element. Summary of the Invention

[0005] According to a first aspect of the present disclosure, a waveguide is provided, comprising: a metal shell, the metal shell having a rectangular parallelepiped shape, and an opening provided in one side surface of the metal shell, the area of ​​the opening being smaller than the area of ​​the side surface; a slow-wave medium, the slow-wave medium having a refractive index greater than 1, being accommodated in the metal shell, having a rectangular parallelepiped shape, and each inner surface of the metal shell being in contact with a corresponding surface of the slow-wave medium; and two feeding probes, the two feeding probes being respectively located at two ends of the metal shell, each feeding probe being inserted into the slow-wave medium through the metal shell. ; a slot plate, which covers the opening of the metal shell and is fitted with the slow-wave medium, and the slot plate is arranged to form a metal layer including a plurality of slots on one side of the slow-wave medium; a plurality of diodes arranged on the slot plate, the plurality of diodes corresponding one-to-one to the plurality of slots, each diode being arranged to span the corresponding slot, and the cathode of each diode being electrically connected to the metal shell; a plurality of photodetectors arranged on the slot plate, the plurality of photodetectors corresponding one-to-one to the plurality of diodes, and each photodetector being electrically connected to the anode of the corresponding diode.

[0006] According to some exemplary embodiments of the present disclosure, each of the plurality of diodes is a PIN diode.

[0007] According to some exemplary embodiments of the present disclosure, each of the multiple photodetectors includes a photoelectric conversion module, which includes: a substrate, which is configured to support and draw out the generated current; a thermoelectric conversion layer, which is located on the substrate and is configured to convert the received heat into electricity; a heat transfer layer, which is located on the thermoelectric conversion layer and is configured to conduct the received heat to the thermoelectric conversion layer; and a photothermal conversion layer, which is located on the heat transfer layer and is configured to absorb incident light and convert it into heat.

[0008] According to some exemplary embodiments of the present disclosure, in a photoelectric conversion module: the substrate is formed of silicon; the thermoelectric conversion layer is formed of aluminum nitride; the heat transfer layer is formed of gold; and the photothermal conversion layer includes a plurality of silver nanoparticles.

[0009] According to some exemplary embodiments of the present disclosure, each of the plurality of silver nanoparticles has a rectangular parallelepiped shape, the top and bottom surfaces of the rectangular parallelepiped being squares with side lengths ranging from 45 nm to 65 nm, and a height ranging from 50 nm to 80 nm.

[0010] According to some exemplary embodiments of the present disclosure, each of the plurality of photodetectors further includes an optical lens module configured to collect an incident light beam to generate a focused light beam focused on the light-to-heat conversion layer of the photoelectric conversion module.

[0011] According to some exemplary embodiments of the present disclosure, the optical lens module includes a superlens structure, and the superlens structure includes: a transparent disc-shaped substrate; a plurality of nanopillars arranged on the surface of the disc-shaped substrate, each nanopillar being made of titanium dioxide, having a cylindrical shape, a height of 600 nm, and a diameter in the range of 40 nm to 200 nm, wherein the diameter of each nanopillar in the plurality of nanopillars gradually decreases from the center to the edge of the disc-shaped substrate.

[0012] According to some exemplary embodiments of the present disclosure, the diameter of each nanopillar in the plurality of nanopillars gradually decreases in a parabolic form from the center to the edge of the disk-shaped substrate.

[0013] According to some exemplary embodiments of the present disclosure, the slit plate includes a transparent substrate and a metal layer including the multiple slits formed on a first side of the transparent substrate, the metal layer is adhered to the slow-wave medium, and the multiple diodes and the multiple photodetectors are arranged on a second side of the transparent substrate opposite to the first side.

[0014] According to some exemplary embodiments of the present disclosure, the transparent substrate is formed of glass.

[0015] According to some exemplary embodiments of the present disclosure, the slot plate is a metal plate including the plurality of slots.

[0016] According to some exemplary embodiments of the present disclosure, the slow-wave medium is formed of polytetrafluoroethylene.

[0017] According to some exemplary embodiments of the present disclosure, the waveguide further includes at least one supporting column, which is located on a side of the metal shell opposite to the opening, passes through the metal shell and abuts against the slow-wave medium.

[0018] According to some exemplary embodiments of the present disclosure, the plurality of slots are arranged in a row of slots arranged in a straight line along the extension direction of the long side of the slot plate, and the length L and width W of each slot, as well as the period distance P of the plurality of slots, are determined by the following equation: L = (λ g / 5)~(λ g / 2), W=L / 10, P=(λ g / 5)~(λ g / 3), λ g =λ / neff, where λg is the transmission wavelength of the electromagnetic wave in the waveguide, λ is the input wavelength of the electromagnetic wave, neff is the equivalent refractive index of the slow-wave medium of the waveguide, and the extension direction of each slot along the length of the slot is parallel to each other.

[0019] According to some exemplary embodiments of the present disclosure, the multiple slits are arranged into a row of slits arranged in a straight line along the extension direction of the long side of the slit plate, the length of each slit is 5.1 mm, the width is 0.5 mm, the periodic distance of the multiple slits is 3.9 mm, and the slits are parallel to each other along the extension direction of the length of the slit.

[0020] According to a second aspect of the present disclosure, a beam steering device is provided, comprising: a waveguide according to the first aspect of the present disclosure and its various exemplary embodiments; a light control device, comprising: a light emitting diode array comprising a plurality of light emitting diodes, wherein the plurality of light emitting diodes correspond one-to-one to the plurality of photodetectors; a controller, configured to independently control the lighting and shutting down of each light emitting diode in the light emitting diode array, and further configured to light up the corresponding light emitting diode in response to a received control signal in the form of a binary number to illuminate the corresponding photodetector.

[0021] According to the third aspect of the present disclosure, a beam steering method is provided, which is applied to the beam steering device according to the second aspect of the present disclosure, including: obtaining the control signal in the binary form; and lighting up the corresponding light-emitting diode among the multiple light-emitting diodes in response to the control signal.

[0022] According to a fourth aspect of the present disclosure, a method for manufacturing a photodetector is provided, which is applied to a waveguide according to the present disclosure, and the manufacturing method includes: forming a thermoelectric conversion layer on a first substrate; forming a heat transfer layer on the thermoelectric conversion layer; forming a photothermal conversion layer on the heat transfer layer; depositing a titanium dioxide layer on a second substrate; patterning the titanium dioxide layer to generate a superlens structure including a plurality of nanocolumns; and bonding the superlens structure to the photothermal conversion layer using an optical adhesive. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The specific embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings so that more details, features and advantages of the present disclosure can be more fully appreciated and understood; in the accompanying drawings:

[0024] Figure 1a The structure of a waveguide according to an exemplary embodiment of the present disclosure is schematically shown in a perspective view;

[0025] Figure 1b Shown Figure 1a A longitudinal cross-sectional view of the waveguide shown in , obtained by cutting along its longitudinal axis;

[0026] Figure 1c yes Figure 1a The circuit principle diagram of part A in FIG;

[0027] Figure 2 According to some exemplary embodiments of the present disclosure, it is schematically shown Figure 1a and Figure 1b The structure of the photodetector in the waveguide is shown;

[0028] Figure 3 According to some exemplary embodiments of the present disclosure, it is schematically shown Figure 2 A structure of a photoelectric conversion module in the photodetector shown;

[0029] Figure 4a According to some exemplary embodiments of the present disclosure, it is further schematically shown that Figure 3 Details of the photoelectric conversion module shown;

[0030] Figure 4b 、 Figure 4c and Figure 4d In the form of a simulation diagram, it schematically shows Figure 4a The photoelectric conversion module shown includes a light-to-heat conversion layer comprising silver nanoparticles, which absorbs incident light.

[0031] Figure 5 According to some exemplary embodiments of the present disclosure, it is schematically shown Figure 2 A structure of an optical lens module in the photodetector shown;

[0032] Figure 6 According to some exemplary embodiments of the present disclosure, it is schematically shown Figure 5 A distribution pattern of nanopillars in the optical lens module shown;

[0033] Figure 7 According to some other exemplary embodiments of the present disclosure, it is schematically shown that Figure 5 A distribution pattern of nanopillars in the optical lens module shown;

[0034] Figure 8 In the form of a simulation diagram, it is schematically shown that Figure 7 The focusing effect of the optical lens module with the nano-pillar distribution pattern shown;

[0035] Figure 9 The structure of a beam steering device according to an exemplary embodiment of the present disclosure is schematically shown in the form of a block diagram;

[0036] Figure 10 A light control device according to an exemplary embodiment of the present disclosure and a situation in which a light emitting diode in the light control device is illuminated are shown;

[0037] Figure 11 Schematically shows the Figure 10 The control performed by the light control device shown and the corresponding situations of the gaps in the waveguide;

[0038] Figure 12 A beam steering method according to an exemplary embodiment of the present disclosure is schematically illustrated in the form of a flowchart;

[0039] Figure 13 The control of beam pointing at three angles is schematically shown in the form of a simulation diagram;

[0040] Figure 14 Schematically shows Figure 13 The Smith charts corresponding to the three beam pointing angles shown;

[0041] Figure 15 A method for manufacturing a photodetector according to an exemplary embodiment of the present disclosure is schematically illustrated in the form of a flow chart.

[0042] Figure 16 The flowchart of a process for manufacturing a photodetector according to an exemplary embodiment of the present disclosure is schematically shown.

[0043] It should be understood that the contents shown in the drawings are only schematic and therefore are not necessarily drawn to scale. In addition, throughout the drawings, identical or similar features are indicated by identical or similar reference numerals. DETAILED DESCRIPTION

[0044] The following description provides specific details of each exemplary embodiment of the present disclosure so that those skilled in the art can fully understand and implement the technical solutions according to the present disclosure.

[0045] See also Figure 1a and Figure 1b , which together schematically illustrate the structure of a waveguide according to an exemplary embodiment of the present disclosure. Figure 1a is a perspective view of the waveguide 100. Figure 1b 1 is a longitudinal cross-sectional view taken along the longitudinal axis of the waveguide 100. As shown in the figure, the waveguide 100 includes a metal housing 110, a slow-wave medium 120, two feeding probes 130, a slot plate 140 including a plurality of slots 150, a plurality of diodes 160, a plurality of photodetectors 170, and a plurality of support pillars 180.

[0046] The metal shell 110 has a rectangular parallelepiped shape, with one side of the rectangular parallelepiped having an opening. The area of ​​the opening is smaller than the area of ​​the side of the metal shell 110 having the opening. It should be understood that, in this disclosure, with respect to a rectangular parallelepiped, the term "side" refers to the surface of the rectangular parallelepiped ... As a non-limiting example, the slow-wave medium 120 may be formed of polytetrafluoroethylene (i.e., PTFE). Two feeding probes 130 are respectively located at both ends of the metal shell 110. Each feeding probe 130 passes through the metal shell 110 and is inserted into the slow-wave medium 120. One feeding probe 130 is used to input electromagnetic waves into the slow-wave medium 120, and the other feeding probe 130 is used to output electromagnetic waves from the slow-wave medium 120. It should be understood that Figure 1b 1 and 2. It is shown that the feeding probe 130 passes through the metal shell 110 from the side opposite to the opening and is inserted into the slow-wave medium 120. However, it should be understood that Figure 1b The arrangement of the feeding probe 130 shown is merely exemplary and not restrictive. In other exemplary embodiments of the present disclosure, the feeding probe 130 may also pass through the metal housing 110 from other side surfaces or end surfaces and be inserted into the slow-wave medium 120. The present disclosure does not impose any restrictions on the manner in which the feeding probe 130 passes through the metal housing 110 and is inserted into the slow-wave medium 120 at the end of the metal housing 110, as long as they are used for input and output of electromagnetic waves at both ends of the waveguide 100.

[0047] The slot plate 140 covers the opening in the metal housing 110 and contacts the corresponding surface of the slow-wave medium 120 , whereby the slot plate 140 is arranged to form a metal layer including a plurality of slots 150 above the slow-wave medium 120 . Figure 1b In the exemplary embodiment shown, the slit plate 140 may include a transparent substrate 140-1 and a metal layer 140-2 including a plurality of slits 150 formed on a first side of the transparent substrate 140-1. Figure 1b As shown, the first side of the transparent substrate 140 is the side thereof adjacent to the slow-wave medium 120, and the second side thereof is the side opposite to the first side and away from the slow-wave medium 120. Figure 1b In the illustrated embodiment, a plurality of diodes 160 and a plurality of photodetectors 170 are arranged on the second side of the transparent substrate 140-1, which will be described in detail below. In some exemplary embodiments of the present disclosure, the transparent substrate 140-1 may be formed of glass. The metal layer 140-2 may be formed of any suitable metal with high electrical conductivity. As non-limiting examples, the metal layer 140-2 may be formed of aluminum, copper, or silver. It should be understood that Figure 1b The structure of the slot plate 140 shown is merely exemplary and not restrictive. According to other exemplary embodiments of the present disclosure, the slot plate 140 may also be a metal plate including a plurality of slots 150. Therefore, the present disclosure does not impose any restrictions on the specific structure of the slot plate 140, as long as it can be arranged to form a metal layer including a plurality of slots 150 above the slow-wave medium 120. Figure 1a and Figure 1b In the exemplary embodiment shown, the plurality of slots 150 on the slot plate 140 are arranged in a row in a straight line along the longitudinal direction of the waveguide 100, and the slots 150 are parallel to each other along the direction in which the slots extend. However, this arrangement of the plurality of slots 150 is merely exemplary and not restrictive. In other exemplary embodiments of the present disclosure, the plurality of slots 150 may also be arranged in two or more rows, or in other patterns, depending on the desired slot distribution pattern.

[0048] According to the present disclosure, in the waveguide 100, the length L, width W of the slot 150, and the period distance P of the plurality of slots 150 can be determined according to the following equation: L=(λ g / 5)~(λ g / 2), W=L / 10, P=(λ g / 5)~(λ g / 3), λ g =λ / neff, where λ g is the transmission wavelength of the electromagnetic wave in the waveguide 100, λ is the input wavelength of the electromagnetic wave, and neff is the equivalent refractive index of the slow-wave medium 120 in the waveguide 100. It should be noted that the periodic distance of the plurality of slots 150 refers to the same side of two adjacent slots 150 (for example, Figure 1a and Figure 1b (the same long side of two adjacent slots 150 in the waveguide 100). In some exemplary embodiments, the length L of the slots 150 in the waveguide 100 may be 5.1 mm, the width W may be 0.5 mm, and the periodic distance of the plurality of slots 150 may be 3.9 mm. It should be understood from the above equation that the length, width, and periodic distance of the slots 150 can be adjusted accordingly based on the operating frequency band of the electromagnetic wave in actual applications.

[0049] A plurality of diodes 160 and a plurality of photodetectors 170 are arranged on the slot plate 140, as shown in FIG. Figure 1b As shown, it is arranged on the second side of the slot plate 140. A plurality of diodes 160 correspond one-to-one to the plurality of slots 150, and each diode is arranged to span the corresponding slot 150 at a position approximately in the middle of the long side of the corresponding slot 150. The cathode of each diode 160 is grounded, for example, electrically connected to the metal housing 110 of the waveguide 100. A plurality of photodetectors 170 correspond one-to-one to the plurality of diodes 160, and each photodetector 170 is electrically connected to the anode of the corresponding diode 160. See Figure 1c , which shows Figure 1a In the circuit principle of Part A, Figure 1a Part A in FIG includes a slot 150 on the slot plate 140 and its corresponding diode 160 and photodetector 170. Figure 1c As shown, the diode 160 is arranged to span the corresponding slot 150 at a position approximately in the middle of the long side of the corresponding slot 150 (this position is not required, and a position further to one side is also possible). The cathode of the diode 160 is grounded (for example, the metal housing 110 of the waveguide 100), and the anode of the diode 160 is electrically connected to the corresponding photodetector 170. It should be understood that the diode 160 can be any suitable diode. As a non-limiting example, the diode 160 can be a positive-intrinsic-negative diode (i.e., a PIN diode). In some other exemplary embodiments of the present disclosure, the diode 160 can also be a Schottky diode. The present disclosure does not impose any limitation on the specific type of diode.

[0050] like Figure 1b As shown, the waveguide 100 further includes at least one support post 180. The at least one support post 180 passes through the metal housing 110 on a side of the metal housing 110 opposite the opening thereof and abuts the slow-wave medium 120. The support post 180 is used to apply a certain force to the slow-wave medium 120 to maintain contact with the slot plate 140. However, it should be understood that the support post 180 is not required. In other exemplary embodiments of the present disclosure, the waveguide 100 may also not include the support post 180.

[0051] During the application of the waveguide 100, when the photodetector 170 is not illuminated by light, the diode 160 is in an off state, so that the energy of the electromagnetic wave transmitted in the waveguide 100 can be radiated from the gap 150; and when the photodetector 170 is illuminated by the light-controlled device used to drive it, the photodetector 170 absorbs the incident light and generates a corresponding current to provide to the diode 160. The current can be used as an electrical control signal for the diode 160, which causes the diode 160 to change from an off state to an on state, so that the current flows across the gap 150 through the diode 160, thereby preventing the energy of the electromagnetic wave transmitted in the waveguide 100 from being radiated from the gap 150. Therefore, the waveguide 100 according to the exemplary embodiment of the present disclosure can dynamically control the slot distribution pattern of the multiple slots 150 in the waveguide 100 simply through optical control, thereby enabling corresponding dynamic tuning of the slot radiation energy, without the need for additional wiring on the waveguide 100 to connect to the corresponding level controller or circuit. This significantly simplifies the structure of the waveguide and its control method. In addition, the waveguide 100 according to the exemplary embodiment of the present disclosure can achieve dynamic tuning of the slot radiation energy through dynamic control of the multiple slots 150. Therefore, during the beam steering process, different beam directions can be achieved by controlling the amount of slot radiation energy at different positions on the waveguide front, thereby improving the beamforming characteristics. Therefore, the waveguide 100 according to the exemplary embodiment of the present disclosure has reconfigurable characteristics.

[0052] See also Figure 2 , which schematically shows the structure of a photodetector according to the present disclosure in the form of a block diagram, and the photodetector can be applied to Figure 1a and Figure 1b In the waveguide 100 shown in FIG. Figure 2 As shown, the photodetector 170 may include a photoelectric conversion module 170-1 and an optical lens module 170-2. The photoelectric conversion module 170-1 is used to absorb incident light and convert the absorbed incident light into an electrical signal, that is, an electrical control signal that can be used for the corresponding diode 160. The optical lens module 170-2 is used to collect the incident light beam to generate a focused light beam focused on the photothermal conversion layer of the photoelectric conversion module 170-1, thereby improving the collection effect of the incident light. The optical lens module 170-2 can have any suitable structure, including but not limited to a super lens structure, a micro lens array, etc. The present disclosure does not limit the specific structure of the optical lens module 170-2. In addition, it should be understood that, Figure 2 The structure of the photodetector shown is merely exemplary and not restrictive. According to other exemplary embodiments of the present disclosure, the photodetector may include only the photoelectric conversion module 170 - 1 without the optical lens module 170 - 2 .

[0053] See also Figure 3 , which schematically illustrates, according to some exemplary embodiments of the present disclosure, Figure 2 The structure of the photoelectric conversion module in the photoelectric detector is shown in FIG. Figure 3 As shown, photoelectric conversion module 170-1 includes a substrate 170-1a, a thermoelectric conversion layer 170-1b, a heat transfer layer 170-1c, and a photothermal conversion layer 170-1d. Substrate 170-1a supports the remaining layers and also outputs the generated current. Thermoelectric conversion layer 170-1b, located on substrate 170-1a, converts the received heat into electricity. Heat transfer layer 170-1c, located on thermoelectric conversion layer 170-1b, conducts the received heat downward to thermoelectric conversion layer 170-1b. Photothermal conversion layer 170-1d, located on heat transfer layer 170-1c, strongly absorbs incident light and converts it into heat. Thus, photoelectric conversion module 170-1 is able to absorb incident light and, in response, generate a current that can be used as an electrical control signal. In some exemplary embodiments, the substrate 170-1a may be formed of silicon, the thermoelectric conversion layer 170-1b may be formed of aluminum nitride, the heat transfer layer 170-1c may be formed of a metal with high thermal conductivity (e.g., gold, silver, aluminum, etc.), and the light-to-heat conversion layer 170-1d may include a plurality of silver nanoparticles 171-1e. The silver nanoparticles 171-1e may strongly absorb incident light and convert it into heat, as will be described in detail below.

[0054] See also Figure 4a , which further schematically illustrates according to some exemplary embodiments of the present disclosure Figure 3 Details of the photoelectric conversion module are shown. Figure 4a The structure of the photoelectric conversion module shown is similar to Figure 3 The structures of the photoelectric conversion modules shown are similar, the only difference is that Figure 4a The shape of the silver nanoparticle 170-1e is shown in FIG. Therefore, only this difference will be described below, and the rest will not be described in detail. Figure 4a As shown, each of the plurality of silver nanoparticles 170-1e included in the photoelectric conversion module 170-1 has a rectangular parallelepiped shape, the top and bottom surfaces of the rectangular parallelepiped are squares with side lengths ranging from 45nm to 65nm, and the height of the rectangular parallelepiped is ranging from 50nm to 80nm.

[0055] See also Figure 4b 、 Figure 4c and Figure 4d , which schematically show Figure 4a The simulation diagram of the absorption effect of the light-to-heat conversion layer including nano-silver particles on the incident light in the photoelectric conversion module shown in FIG. Figure 4b As shown, it shows Figure 4aThe simulation results of the absorption effect of a single silver nanoparticle 170-1e on incident light in the photoelectric conversion module of FIG. As can be seen from the figure, a single silver nanoparticle 170-1e has a strong absorption effect on incident light, especially in Figure 4b The z-axis is shown at 0 nm, i.e., the junction of the nanosilver particles 170-1e and the heat transfer layer 170-1c. Due to the strong reflective properties and non-transmitting properties of the heat transfer layer 170-1c (generally formed of gold, silver, or aluminum), there is a strong absorption of incident light. Therefore, the structure formed by a single nanosilver particle and the substrate has perfect absorption properties. In addition, Figure 4c As shown in FIG, it shows the simulation results of the absorption effect of the light-to-heat conversion layer 170-1d including the nano-silver particles 170-1e on incident light of different wavelengths. Figure 4a The light-to-heat conversion layer 170-1d including the silver nanoparticles 170-1e can absorb almost all the light with a wavelength of about 540nm. Figure 4d Figure 1 shows simulation results of the absorption effect of light-to-heat conversion layer 170-1d, including silver nanoparticles 170-1e, on incident light at different angles of incidence. As shown in the figure, the absorption rate of light-to-heat conversion layer 170-1d, including silver nanoparticles 170-1e, remains essentially unchanged and approaches perfect absorption for incident angles θ ranging from 0° (normal incidence) to ±60°. This reduces the effects of varying illumination angles and significantly improves light absorption efficiency.

[0056] See also Figure 5 , which schematically illustrates, according to some exemplary embodiments of the present disclosure, Figure 2 A structure of an optical lens module in a photodetector as shown. Figure 5 As shown, the optical lens module 170-2 includes a super lens structure that can focus the incident light to form a focused light spot on the photothermal conversion layer 170-1d of the photoelectric conversion module. As a result, the energy of the incident light can be focused as much as possible on the photothermal conversion layer 170-1d, thereby greatly improving the light beam collection capability of the incident light. Therefore, the optical lens module 170-2 including the super lens structure achieves a focusing effect similar to a convex lens based on the structure of the planar layer. The optical lens module 170-2 includes a substrate 170-2a, which has a disc shape and is transparent. The optical lens module 170-2 also includes a plurality of nanopillars 170-2b arranged on the surface of the substrate 170-2a. Each nanopillar 170-2b is made of titanium dioxide, has a cylindrical shape, a height of 600nm, and a diameter ranging from 40nm to 200nm.

[0057] The plurality of nanorods 170-2b may have a certain distribution pattern on the substrate 170-2a to achieve the overall phase distribution required by the optical lens module 170-2. Figure 6 , which schematically shows a distribution pattern of multiple nanopillars on a substrate. Figure 6 As shown, the diameter of each nanopillar in the plurality of nanopillars 170-2b gradually decreases from the center to the edge of the disk-shaped substrate 170-2a. In other words, the diameter of the nanopillar 170-2b increases as it approaches the center of the disk-shaped substrate 170-2a, and decreases as it approaches the edge of the disk-shaped substrate 170-2a. Figure 6 The diagram in clearly shows this distribution.

[0058] See also Figure 7 , which schematically shows another distribution pattern of multiple nanopillars on the substrate. Figure 7 As shown, the diameter of each nanorod 170 - 2 b in the plurality of nanorods 170 - 2 b gradually decreases in a parabolic form from the center to the edge of the disk-shaped base 170 - 2 a . Figure 7 The view (a) in FIG. 1 shows the relationship between the radius of each nanorod 170 - 2 b and its position in the disk-shaped substrate 170 - 2 a, wherein at the center of the circle (ie, Figure 7 The radius of the nanorod 170 - 2 b at the position 0 μm in the view (a) is the largest, and the radius of each nanorod 170 - 2 b gradually decreases in a parabolic form from the center to the edge. Figure 7 The view (b) in FIG. 1 shows the overall phase distribution of the optical lens module 170 - 2 based on the radius distribution of the nanorods 170 - 2 b shown in view (a). It should be understood that Figure 7 The coordinates x and y in view (b) correspond to Figure 5 The coordinates x and y are shown in .

[0059] See also Figure 8 , which schematically shows the Figure 7 The focusing effect of the optical lens module shown is the nanopillar distribution pattern. Figure 8 Shown are the Figure 7 The focusing effect of the optical lens module with the nanopillar distribution pattern on blue light, green light, and red light, for example, the spot shape in the xz plane and the xy plane, and the field intensity at the focus. From these simulation figures, it can be seen that the optical lens module can achieve a good focusing effect on the incident light. Figure 7 The optical lens module with the nano-pillar distribution pattern shown achieves a focusing effect similar to a convex lens based on the structure of the planar layer. In addition, it should be understood that Figure 8The coordinates x, y, and z in each view correspond to Figure 5 The coordinates x, y, and z are shown in .

[0060] See also Figure 9 , which schematically shows the structure of a beam steering device according to an exemplary embodiment of the present disclosure in the form of a block diagram. Figure 9 As shown, the beam steering device 300 includes the aforementioned Figure 1a 、 Figure 1b The waveguide 100 and the light control device 310 described are shown in FIG. The light control device 310 includes a light emitting diode array 320 and a controller 330. The light emitting diode array 320 includes a plurality of light emitting diodes, wherein the plurality of light emitting diodes correspond one to one with the plurality of photodetectors 170 in the waveguide 100. It should be understood that any suitable type of light emitting diode can be used to form the light emitting diode array 320, and the present disclosure does not impose any limitation on the specific type of light emitting diode. The controller 330 is configured to independently control the lighting and shutoff of each light emitting diode in the light emitting diode array 320, and is further configured to light up the corresponding light emitting diode in response to the received control signal in the form of a binary number to illuminate the corresponding photodetector 170. See FIG. Figure 10 , which shows a light control device according to an exemplary embodiment of the present disclosure, and a situation when the light emitting diode in the light control device is lit. Figure 10 In the light control device shown, a plurality of light emitting diodes are arranged in a straight line and can emit light under the control of a controller. Figure 1a 、 Figure 1b The waveguide 100 shown is used for light control. Figure 11 , which schematically shows the Figure 10 The control performed by the optical control device shown in FIG. and the corresponding situations of each gap in the waveguide. Figure 11 As shown, the controller of the light control device 310 receives a control signal in the form of a binary number, such as the binary number "0101110..." shown in the figure. Each bit of the binary number corresponds to a light emitting diode in the light emitting diode array 320. Figure 11 In the illustrated case, "0" indicates that the corresponding LED is on, and "1" indicates that the corresponding LED is off. When the LED is on, the corresponding diode 160 is turned on, causing current to flow across the gap 150. When the LED is off, the corresponding diode 160 is turned off, and no current flows across the gap 150. Figure 11 The lower view shows the situation of each slot 150 in the waveguide 100 based on the control signal in the form of a binary number, wherein the slot 150 corresponding to the light-emitting diode that is lit cannot radiate energy, while the slot 150 corresponding to the light-emitting diode that is turned off can radiate energy.

[0061] The beam steering device 300 is based on the holographic principle, and thus can control the different directions of the beam by controlling the size of the radiation energy of the slots at different positions on the waveguide array.

[0062] According to the holographic principle, the wave function of the target wave can be expressed as follows:

[0063]

[0064] Among them, r represents the distance between the waveguide array and the target wave source, θ0 is the angle of the target wave relative to the horizontal plane, that is, the pitch angle, It is the deflection angle of the target wave in the horizontal plane.

[0065] The wave function of the reference wave can be expressed as follows:

[0066]

[0067] Therefore, using the holographic principle, the interference pattern of the array can be obtained as follows:

[0068]

[0069]

[0070] The analysis using the amplitude sampling function is as follows:

[0071]

[0072] in, It represents the amplitude of the interference pattern of the array.

[0073] Substituting the above amplitude samples into the following formula, the far-field radiation pattern can be calculated:

[0074]

[0075]

[0076] In the above equations 6 and 7, μ0 is the air permeability, a f is the attenuation, D s is the spacing between periodic gaps, A c is the cross-sectional area of ​​the rectangular waveguide in the transmission direction, and Re{η} represents the real part of the wave impedance.

[0077] Based on the far-field radiation pattern obtained, binary sampling can be performed, thereby obtaining a corresponding binary number (i.e., 0 and 1). This binary number can be provided as a control signal to the controller 330 of the light control device 310 to control the lighting and shutting down of multiple light-emitting diodes in the light-emitting diode array 320. Accordingly, the light control device 310 performs light control on the waveguide 100, thereby controlling the conduction and shutoff of the corresponding diodes 160, thereby achieving control over whether each slot 150 can radiate energy, and ultimately achieving control over the different directions of the beam. In other words, by combining the holographic principle with the binary method, the algorithm calculates different slot distribution patterns, and the obtained binary number is input as a control signal to the light control device 310, and the corresponding light is used to illuminate the waveguide 100 to achieve the slot distribution pattern, thereby achieving control over the direction of the beam.

[0078] See also Figure 12 , which schematically illustrates a beam steering method according to an exemplary embodiment of the present disclosure in the form of a flow chart, and the beam steering method can be applied to Figure 9 The beam steering device 300 shown in FIG. Figure 12 As shown, the beam steering method 500 includes steps 510 and 520:

[0079] In step 510, the control signal in binary form is obtained;

[0080] In step 520, corresponding light emitting diodes among the plurality of light emitting diodes are illuminated in response to the control signal.

[0081] The beam steering method 500 can be applied to Figure 9 The beam steering device 300 shown, therefore, when a corresponding light-emitting diode among the plurality of light-emitting diodes is lit based on a control signal in the form of a binary number, the waveguide 100 in the beam steering device 300 is driven by the corresponding light, so that the plurality of slots 150 included therein will have corresponding open (i.e., allowing radiation energy) and closed (prohibiting radiation energy) conditions to generate corresponding slot distribution patterns, thereby enabling control of different directionality of the beam.

[0082] See also Figure 13 , schematically illustrates the control of beam pointing at three angles in the form of a simulation diagram. As described in detail above, by utilizing the holographic principle combined with the binary method, the algorithm calculates different gap distribution patterns, and can obtain binary numbers corresponding to different beam pointing directions. This binary number can be provided as a control signal to the optical control device to achieve control of the gap in the waveguide, thereby achieving control of the beam pointing direction. Figure 13In the simulation diagram shown, HFSS was used to simulate the energy distribution of different slots to obtain the following three pointing angles: -30°, 0°, and 30°. The slots on the waveguide are arranged in a single straight line, with a total of 64 slots. For each angle, the first 10 bits of the binary number are distributed as follows: 11001001100..., 0111001110..., 0000111110... (For specific binary numbers, see Figure 13 The three simulated radiation patterns are shown in Figure 2. Figure 13 The three views are shown in Figure 2.

[0083] See also Figure 14 , which schematically shows Figure 13 The Smith charts corresponding to the beam pointing downward for the three pointing angles shown in FIG. Figure 14 As shown in the Smith chart corresponding to the three directional angles, the respective graphs are concentrated in the center of the chart. This indicates that the waveguide designed according to the principles of the present disclosure achieves perfect port impedance matching in this specific frequency range at these three directional angles, thereby ensuring efficient input energy.

[0084] See also Figure 15 , which schematically illustrates a method for manufacturing a photodetector according to an exemplary embodiment of the present disclosure in the form of a flow chart, wherein the photodetector is, for example, Figure 2 The photodetector 170 shown, therefore, can be applied to a waveguide according to the present disclosure. Figure 15 As shown, the manufacturing method 700 includes steps 710, 720, 730, 740, 750 and 760:

[0085] In step 710, a thermoelectric conversion layer is formed on a first substrate;

[0086] In step 720, a heat transfer layer is formed on the thermoelectric conversion layer;

[0087] In step 730, a light-to-heat conversion layer is formed on the heat transfer layer;

[0088] In step 740, a titanium dioxide layer is deposited on a second substrate;

[0089] In step 750 , the titanium dioxide layer is patterned to generate a metalens structure including a plurality of nanorods;

[0090] In step 760, the super lens structure and the light-to-heat conversion layer are bonded together using an optical adhesive.

[0091] It should be understood that steps 710, 720, and 730 in manufacturing method 700 are used to manufacture a photoelectric conversion module, such as photoelectric conversion module 170-1, and steps 740 and 750 in manufacturing method 700 are used to manufacture an optical lens module, such as photoelectric lens module 170-2, which includes a superlens structure. According to some exemplary embodiments of the present disclosure, the first substrate can be formed of silicon, the thermoelectric conversion layer can be formed of aluminum nitride, the heat transfer layer can be formed of gold, and the photothermal conversion layer can include multiple silver nanoparticles. In addition, the heat transfer layer can also be formed of silver or aluminum, as long as it has good thermal conductivity. The second substrate can also be formed of silicon. In step 760, the optical adhesive can be polymethyl methacrylate (i.e., PMMA). However, it should be understood that any suitable optical adhesive can be used in the manufacturing method according to the present disclosure, and the present disclosure does not impose any restrictions on the specific type of optical adhesive.

[0092] See also Figure 16 , which schematically shows a process flow for manufacturing a photodetector according to an exemplary embodiment of the present disclosure. The photodetector manufactured using this process flow corresponds to Figure 2 The photoelectric detector shown in FIG. 1 includes an optical lens module and a photoelectric conversion module. Figure 16 As shown, in order to manufacture an optical lens module, an atomic layer deposition process (i.e., ALD) is used to form a titanium dioxide layer on the surface of a silicon substrate, and then a photoresist layer (i.e., PR layer) is formed on the surface of the titanium dioxide layer by a spin coating process, and finally a nanoimprint process (i.e., NIL) and an inductively coupled plasma etching process (i.e., ICP) are used to pattern the titanium dioxide layer to form a plurality of nanopillars, thereby making an optical lens module; in order to manufacture a photoelectric conversion module, an electron beam evaporation process is used to form a gold layer on a silicon + aluminum nitride substrate, and then a plurality of silver nanoparticles are formed on the gold layer by spinning in nitrogen, cleaning, and drying (i.e., a dot spin coating process), thereby making a photoelectric conversion module; finally, the side of the photoelectric conversion module that is dot-spin-coated with silver nanoparticles is bonded to the side of the optical lens module that includes a plurality of nanopillars by using PMMA, thereby making a photodetector. It should be understood that through Figure 16 The photodetector manufactured by the process flow can be applied to the waveguide according to various exemplary embodiments of the present disclosure, for example, Figure 1a and Figure 1b The waveguide 100 is shown in FIG.

[0093] The terms used herein are only used to describe the embodiments in the present disclosure and are not intended to limit the present disclosure. As used herein, the singular forms "a", "an" and "the" are intended to also include the plural forms, unless the context clearly indicates otherwise. It will also be understood that the terms "include" and "comprise" when used in the present disclosure refer to the presence of the features described, but do not exclude the presence of one or more other features or the addition of one or more other features. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. It will be understood that although the terms "first", "second", "third" etc. can be used to describe various features in this article, these features should not be limited by these terms. These terms are only used to distinguish one feature from another.

[0094] It should be understood that the orientation terms such as "upper", "lower", "left", "right", "top", "bottom" and the like used in this disclosure should refer to the orientation arrangements shown in the accompanying drawings, unless otherwise clearly defined in this disclosure.

[0095] Unless otherwise defined, all terms (including technical and scientific terms) used in this disclosure have the same meaning as commonly understood by those skilled in the art to which this disclosure belongs. It is also understood that terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the relevant art and / or the context of this specification, and will not be interpreted in an idealized or overly formal sense unless explicitly defined in this disclosure.

[0096] In the description of the present disclosure, the description of the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present disclosure. In the present disclosure, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples described in the present disclosure and features of different embodiments or examples, unless they are mutually inconsistent.

[0097] It should be understood that the various steps of the methods shown in the flowcharts or otherwise described herein are merely exemplary and do not necessarily imply that the steps of the methods shown or described must be performed as shown or described. Rather, the various steps of the methods shown in the flowcharts or otherwise described herein may be performed in a different order than that disclosed herein, or may be performed simultaneously. Furthermore, the methods shown in the flowcharts or otherwise described herein may include other additional steps, as desired.

[0098] Although the present disclosure has been described in detail in conjunction with certain exemplary embodiments, it is not intended to be limited to the specific forms set forth herein. Rather, the scope of the present disclosure is to be limited only by the appended claims.

Claims

1. A waveguide comprising: a metal shell having a rectangular parallelepiped shape and an opening provided in one side surface of the metal shell, wherein the area of ​​the opening is smaller than the area of ​​the side surface; a slow-wave medium, wherein the refractive index of the slow-wave medium is greater than 1, the slow-wave medium is contained in the metal shell, and the slow-wave medium has a rectangular parallelepiped shape, and each inner surface of the metal shell is in contact with a corresponding surface of the slow-wave medium; Two feeding probes, the two feeding probes are respectively located at two ends of the metal shell, and each feeding probe passes through the metal shell and is inserted into the slow-wave medium; a slot plate, the slot plate covering the opening of the metal shell and being in contact with the slow-wave medium, and the slot plate being arranged to form a metal layer including a plurality of slots on one side of the slow-wave medium; a plurality of diodes arranged on the slot plate, the plurality of diodes corresponding one-to-one to the plurality of slots, each diode being arranged to span the corresponding slot, and a cathode of each diode being electrically connected to the metal housing; A plurality of photodetectors are arranged on the slot plate, the plurality of photodetectors correspond one-to-one to the plurality of diodes, and each photodetector is electrically connected to the anode of the corresponding diode.

2. The waveguide according to claim 1, wherein Each diode of the plurality of diodes is a PIN diode.

3. The waveguide according to claim 1, wherein Each of the plurality of photodetectors includes a photoelectric conversion module, wherein the photoelectric conversion module includes: a substrate configured to support and draw out the generated current; a thermoelectric conversion layer located on the substrate and configured to convert the received heat into electricity; a heat transfer layer located on the thermoelectric conversion layer and configured to conduct the received heat to the thermoelectric conversion layer; The light-to-heat conversion layer is located on the heat transfer layer and is configured to absorb incident light and convert it into heat.

4. The waveguide according to claim 3, wherein: The substrate is formed of silicon; The thermoelectric conversion layer is formed of aluminum nitride; The heat transfer layer is formed of gold; The light-to-heat conversion layer includes a plurality of silver nanoparticles.

5. The waveguide according to claim 4, wherein Each of the plurality of silver nanoparticles has a rectangular parallelepiped shape, a top surface and a bottom surface of the rectangular parallelepiped are both squares with side lengths ranging from 45 nm to 65 nm, and a height ranging from 50 nm to 80 nm.

6. The waveguide according to claim 3, wherein Each of the plurality of photodetectors further includes an optical lens module configured to collect an incident light beam to generate a focused light beam focused on the light-to-heat conversion layer of the photoelectric conversion module.

7. The waveguide according to claim 6, wherein The optical lens module includes a super lens structure, and the super lens structure includes: transparent disc-shaped base; A plurality of nanopillars are arranged on the surface of the disc-shaped substrate, each nanopillar being made of titanium dioxide, having a cylindrical shape, a height of 600 nm, and a diameter ranging from 40 nm to 200 nm, wherein the diameter of each nanopillar in the plurality of nanopillars gradually decreases from the center to the edge of the disc-shaped substrate.

8. The waveguide according to claim 7, wherein From the center to the edge of the disk-shaped substrate, the diameter of each nanorod in the plurality of nanorods gradually decreases in a parabolic form.

9. The waveguide according to claim 1, wherein The slit plate includes a transparent substrate and a metal layer including the multiple slits formed on a first side of the transparent substrate, the metal layer adheres to the slow-wave medium, and the multiple diodes and the multiple photodetectors are arranged on a second side of the transparent substrate opposite to the first side.

10. The waveguide according to claim 9, wherein The transparent substrate is formed of glass.

11. The waveguide according to claim 1, wherein The slot plate is a metal plate including the plurality of slots.

12. The waveguide according to claim 1, wherein The slow-wave medium is formed of polytetrafluoroethylene. 13 . The waveguide according to claim 1 , further comprising at least one supporting post, the at least one supporting post being located on a side of the metal shell opposite to the opening, passing through the metal shell and abutting against the slow-wave medium.

14. The waveguide according to claim 1, wherein The plurality of slots are arranged in a row of slots arranged in a straight line along the extension direction of the long side of the slot plate. The length L and width W of each slot, as well as the period distance P of the plurality of slots, are determined by the following equations: L=(λ g / 5)~(λ g / 2), W=L / 10, P=(λ g / 5)~(λ g / 3), l g =λ / neff, Among them, λ g is the transmission wavelength of the electromagnetic wave in the waveguide, λ is the input wavelength of the electromagnetic wave, neff is the equivalent refractive index of the slow-wave medium of the waveguide, and the extension direction of the slots along the length of the slots are parallel to each other.

15. The waveguide according to claim 1, wherein The multiple slits are arranged into a row of slits arranged in a straight line along the extension direction of the long side of the slit plate, each slit has a length of 5.1 mm and a width of 0.5 mm, a periodic distance of the multiple slits is 3.9 mm, and the slits are parallel to each other along the extension direction of the length of the slit.

16. A beam steering device, comprising: The waveguide according to any one of claims 1 to 15; A light control device, comprising: a light emitting diode array comprising a plurality of light emitting diodes, wherein the plurality of light emitting diodes correspond one-to-one to the plurality of photodetectors; The controller is configured to independently control the lighting and shutoff of each LED in the LED array, and is further configured to light up the corresponding LED in response to the received control signal in the form of a binary number to illuminate the corresponding photodetector.

17. A beam steering method, applied to the beam steering device according to claim 16, comprising: Obtaining the control signal in binary form; In response to the control signal, a corresponding light emitting diode among the plurality of light emitting diodes is illuminated.

18. A method for manufacturing a photodetector, the photodetector being applied to the waveguide according to claim 7, the method comprising: forming a thermoelectric conversion layer on the first substrate; forming a heat transfer layer on the thermoelectric conversion layer; forming a light-to-heat conversion layer on the heat transfer layer; depositing a titanium dioxide layer on a second substrate; patterning the titanium dioxide layer to generate a metalens structure comprising a plurality of nanopillars; The super lens structure and the light-to-heat conversion layer are bonded together using an optical adhesive.

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