Complex amplitude dynamic modulation unit and complex amplitude dynamic modulation method

Abstract

The present invention discloses a complex amplitude dynamic modulation unit and a modulation method, including a modulation module, and the modulation module constitutes a complex amplitude dynamic modulation unit of a closed-loop structure; and also includes: an excitation module for inputting an excitation signal to the modulation module to change the optical properties of the modulation module. Through the control of the excitation module, at least one modulation module can always be kept in a silent state without being excited, while the other modulation modules are in an excited active state. By regulating the number, position, etc. of the modulation modules that process the silent state, a C-type split ring resonator with different opening directions and opening sizes can be obtained, and even other resonators that are not C-type structures can be obtained. It better overcomes the DC noise and twin image problems of the existing pure amplitude modulation and the serious speckle noise problem caused by the existing pure phase modulation, and achieves the effect of higher precision and less noise in complex amplitude modulation.

Description

Technical Field

[0001] The invention belongs to the field of microelectronics / photoelectronics technology, and in particular relates to a complex amplitude dynamic modulation unit and a complex amplitude dynamic modulation method. Background Art

[0002] With the development of microelectronics technology, signal processing systems need to have the ability to operate in real time. Although digital signal processing technology has developed rapidly, it has great limitations in real-time operation.

[0003] The optical processing system has the ability to efficiently modulate the spatial distribution of the amplitude, phase or polarization state of the light field in real time and has unique broadband performance, fast time response, sensitive reaction, lower driving power and better temperature stability.

[0004] The optical properties of matter mainly refer to the various properties exhibited by the material when absorbing, reflecting and refracting light, as well as the interference and scattering of light caused by the material. Existing technologies often modulate the required optical information by changing the optical properties of matter. Most current light field processing systems rely on liquid crystal spatial light modulators, but the liquid crystal molecules maintain a fixed deflection angle under AC voltage. When the grayscale value of the image at that point changes, the applied voltage changes, and it takes time for the liquid crystal molecules to deflect to the new angle, thus limiting the higher refresh frequency of the image. In addition, the spatial bandwidth product is small, and the large size of the liquid crystal molecules leads to a small field of view, which has a certain angle dependence.

[0005] With the great progress of nano-fabrication technology, metasurface technology can be mass-produced and portable. However, static metasurface pure phase modulation technology has serious speckle noise problems, while pure amplitude modulation has DC noise and twin image problems.

[0006] Theoretically, complex amplitude technology can achieve higher precision and reduce noise, but existing V-shaped nanopores, Huygens metasurfaces, and C-shaped split ring resonators are not suitable for this purpose. Figure 1 The structure of the research is fixed in shape and cannot achieve dynamic modulation. Complex amplitude modulation can only be achieved through the arrangement and combination of different structures. Large-scale synchronous modulation is very difficult and the amplitude modulation amplitude and phase modulation range are very small. In addition, the complex structure involves a very limited spectral bandwidth, and it is even more difficult to combine with functional materials to achieve independent phase and amplitude dynamic modulation. Summary of the invention

[0007] Taking into account the complex manufacturing process, high cost, great application limitations and basically customized nature of the C-type split ring resonator, this application proposes a complex amplitude dynamic modulation unit and a complex amplitude modulation method which have a simple manufacturing process and can be flexibly adjusted according to actual application scenarios.

[0008] As one aspect of the present application, the present invention constructs a complex amplitude dynamic modulation unit through structural design and combining the optical modulation characteristics of the modulation module. The complex amplitude dynamic modulation unit of the present application at least includes an excitation module and more than two modulation modules.

[0009] The modulation module of the present application can be composed of the modulation elements of the existing complex amplitude modulation device, including but not limited to phase change material modulation elements, metasurface modulation elements, etc. After such modulation elements are stimulated by a signal similar to an electrical signal, their optical properties change, that is, the various properties exhibited by their absorption, reflection and refraction of light change. Therefore, the excitation module of the present application constitutes the switch of such a modulation module. On the other hand, under different excitation signals, the optical properties of the modulation module are also different, so the excitation module also constitutes the gear adjuster of the modulation module.

[0010] In the present application, two or more modulation modules form a closed-loop structure; the excitation module inputs an excitation signal to the modulation module to change its optical properties. The combination of the modular closed-loop structural characteristics and the dynamic regulation of the excitation signal makes the complex amplitude dynamic modulation unit extremely flexible.

[0011] The above-mentioned complex amplitude dynamic modulation unit can fully realize the structural advantages of the C-type split ring resonator. Taking the monostable phase change material whose initial state is the insulating phase state as an example, the excitation module inputs a continuous excitation signal to it, that is, the modulation module is in an excitation state with a signal input. In the excitation state, it presents a metallic state; once the excitation signal input is stopped, the phase change material will automatically return to the insulating phase state. If this type of modulation module is used to form a closed-loop modulation unit of the present application, the excitation module only inputs an excitation signal to m of the modulation modules, changes the optical properties of the modulation modules, and transforms them into a metallic state, where m is less than the total number of modulation modules n, and the other modulation modules are in a silent state (insulating phase state) that is not excited, forming a C-type split ring resonator.

[0012] Based on the structural advantages of the C-shaped resonator itself, the present application can also achieve independent modulation of the amplitude by adjusting the number of modulation modules in the silent state and adjusting the opening size; or adjust the position of the modulation module in the silent state and adjust the opening direction to achieve independent modulation of the phase. In this way, independent modulation of the amplitude can be achieved through modular independent regulation, overcoming the DC noise and twin image problems of existing pure amplitude modulation. Independent modulation of the phase can be achieved through modular independent regulation, which effectively solves the serious speckle noise problem caused by existing pure phase modulation.

[0013] The scheme of the present application is also applicable to multi-stable phase change materials. Take a multi-stable phase change material whose initial state is crystalline as an example. The excitation module inputs an instantaneous excitation signal to it, that is, the modulation module is in the excitation state, and in the excitation state, it presents an amorphous state ①, and further inputs an excitation signal, it presents an amorphous state ②, or further inputs an excitation signal, it presents a crystalline state ①; the above amorphous state ①-amorphous state ②-crystalline state ① are all presented under signal excitation, which is the activation state described in the present application. Therefore, for multi-stable phase change materials, their activation state can be either crystalline or amorphous. If this type of modulation module is used to form a closed-loop modulation unit of the present application, the excitation module only inputs an excitation signal to m of the modulation modules, changes the optical properties of the modulation module, and makes it amorphous, while the other modulation modules are in the crystalline state, forming a C-type split ring resonator (the same applies to multi-stable phase change materials whose initial state is amorphous).

[0014] Similarly, by controlling the excitation signals of each modulation module, a resonant structure similar to brackets “()” can be obtained.

[0015] The closed-loop structure described in the present application is a circular ring structure, a square ring structure, a triangular ring structure or any other closed ring structure.

[0016] As can be seen from the above, the complex amplitude dynamic modulation unit does not need to design structural units with different azimuth angles and opening angles, which overcomes the problem of device customization, the problem of complex structural design leading to a very limited spectral bandwidth, the difficulty of large-scale synchronous modulation, and the small amplitude modulation amplitude and phase modulation range. It has a higher spectral bandwidth, simpler manufacturing and design, easier light field operation and lower preparation cost. Furthermore, dynamic modulation is achieved through the excitation module without the need for complex device structure design and array design, which makes operation simpler and manufacturing cost lower.

[0017] In the present application, the arc lengths or side lengths of the modulation modules are equal or unequal; or the widths of the modulation modules are equal or unequal. The splicing of the modulation modules, especially the same modulation modules, makes mechanized manufacturing possible, greatly improving the manufacturing efficiency of the device.

[0018] In the present application, the modulation module can be a phase change material layer, but it is not limited thereto. Those skilled in the art should understand that as long as the modulation module has a signal response (its optical properties change under a certain signal excitation), it is applicable to the present application; when the modulation module is a phase change material, the excitation module includes an electrical signal output module and an electrode corresponding to the modulation module, and the electrical signal output module controls the electrode to input a voltage to the modulation module, and changes the phase state and crystallinity of the phase change material through an electrical pulse, thereby changing its optical properties. In this way, the size of a single modulation module can be as small as a hundred nanometers, and the thickness of each layer of film can be as small as a few nanometers, which is much smaller than the size of the liquid crystal spatial light modulator, and effectively solves the problems of small field of view and liquid crystal crosstalk faced by the liquid crystal spatial light modulator. Moreover, the transformation of the crystalline and amorphous states of the phase change material is achieved by applying an electrical pulse to the modulation layer, and the microelectrode transfers heat and pulse energy to the phase change material. The phase change speed is at the nanosecond level, which can respond to the light modulation capability faster, and the modulation method is simple and low in cost.

[0019] In the present application, the phase change material has two or more phases and is extremely widely available, including but not limited to GST, Sb2S3, GeTe, Sb2Te3, Sb2Te, Ge15Sb85 and other materials.

[0020] Based on the above modulation unit, the present invention relates to the following dynamic modulation method: inputting an excitation signal to a part of the modulation module through an excitation module, so that the part of the modulation module is in an activated state with signal excitation, and the part of the modulation module is in a silent state without signal excitation; by dynamically adjusting the excitation signal, adjusting the position and number of the modulation modules in the silent state, to achieve dynamic modulation of the complex amplitude of the incident light. For example, according to the above scheme, the state of the part of the modulation module is controlled to obtain a C-shaped resonant structure.

[0021] Furthermore, it also includes dynamically regulating the excitation signal to regulate the order optical constant of the modulation module in the activated state to achieve dynamic modulation of the complex amplitude of the incident light.

[0022] Furthermore, the modulation module is a phase change material layer; the excitation module includes an electrical signal output module and electrodes corresponding to the modulation modules one by one, and the electrical signal output module inputs electrical excitation to the modulation module through the electrodes, so that the modulation module undergoes independent dynamic conversion between an activated state and a quiet state, or each modulation module undergoes dynamic conversion under the activated state of different order optical constants.

[0023] Based on the above modulation units, the present invention further provides a complex amplitude dynamic modulator, which at least includes the above modulation unit and other auxiliary modulation units.

[0024] The auxiliary modulation unit described here is: an optical element that can absorb, reflect and refract light; even like the modulation module of the present application, it can use the modulation element of the existing complex amplitude modulation device, including but not limited to phase change material modulation element, metasurface modulation element, etc. After such modulation elements are stimulated by a signal similar to an electrical signal, their optical properties change, that is, their various properties when absorbing, reflecting and refracting light change. In this case, the auxiliary modulation unit includes an auxiliary modulation module with optical regulation and an auxiliary excitation module that inputs an independent excitation signal to the auxiliary modulation module to change the optical properties of the auxiliary modulation module.

[0025] In a preferred embodiment of the present application, the auxiliary modulation module is composed of a plurality of auxiliary modulation sub-modules. For example, a plurality of sub-modules with fan-shaped structures are spliced ​​together to form a pancake-shaped auxiliary modulation module.

[0026] Based on the above modulation units, the present invention also provides a complex amplitude dynamic modulator, which is composed of two or more modulation units. Each modulation unit can not only modulate independently without interfering with each other, but the modulation modules in adjacent modulation units can also form a special resonant structure by combination. For example, two adjacent modulation units are combined to form an X-like structure through the control of an excitation module; for example: a combination of two concentric modulation units, a combination of square closed-loop modulation units of different sizes but the same center.

[0027] Based on the above modulation units, the present invention also provides a complex amplitude dynamic modulator, which is composed of two or more modulation units and auxiliary modulation units, for example, a combination of two square closed-loop modulation units of different sizes but the same center and a square auxiliary modulation unit.

[0028] The beneficial effects of the present invention are as follows: the present invention overcomes the problems of limited spectral bandwidth due to complex structure, difficulty in large-scale synchronous modulation, small amplitude modulation amplitude and phase modulation range, etc., and has higher spectral bandwidth, simpler manufacturing and design, easier light field operation and lower preparation cost; the designed complex amplitude dynamic modulation method can adjust the C-shaped azimuth angle to achieve independent amplitude modulation and adjust the C-shaped opening angle to achieve independent phase modulation by dynamically controlling each modulation module, which better overcomes the DC noise and twin image problems of existing pure amplitude modulation and the serious speckle noise problem caused by existing pure phase modulation, and achieves the effect of higher precision and less noise in complex amplitude modulation. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0030] Figure 1 It is a schematic diagram of an existing C-type split ring resonator complex amplitude modulation unit.

[0031] Figure 2 It is a schematic diagram of the cross-sectional structure of the annular complex amplitude dynamic modulation unit in the present invention.

[0032] Figure 3 It is a schematic diagram of the cross-sectional structure of the modulation module in the annular complex amplitude dynamic modulation unit of the present invention.

[0033] Figure 4 It is a schematic diagram of the structure of the complex amplitude dynamic modulation unit of the present invention.

[0034] Figure 5 It is a schematic diagram of the complex amplitude dynamic modulation method of the present invention.

[0035] Figure 6 It is a schematic diagram of the complex amplitude independent amplitude modulation effect of the present invention.

[0036] Figure 7 It is a schematic diagram of the complex amplitude independent phase modulation effect of the present invention.

[0037] Figure 8 It is a schematic cross-sectional structure diagram of the square ring-shaped complex amplitude dynamic modulation unit of the present invention.

[0038] Fig. 9 It is a schematic diagram of the cross-sectional structure of an X-type complex amplitude dynamic modulation unit composed of two semi-circular ring structures of the present invention.

[0039] Fig.10 It is a cross-sectional structural schematic diagram of a complex amplitude dynamic modulator composed of a circular ring-shaped modulation unit and a circular auxiliary modulation unit with the same center and different radii according to the present invention.

[0040] Fig.11 It is a schematic cross-sectional structure diagram of the dual-ring complex amplitude dynamic modulator of the present invention.

[0041] Fig.12 It is a schematic diagram of the cross-sectional structure of a circular ring-shaped complex amplitude dynamic modulator in which the modulation modules of the present invention have different widths.

[0042] Fig.13 The invention is a circular complex amplitude dynamic modulator for controlling the crystallization degree of the modulation module to realize different order optical constants

[0043] Fig.14 It is the refractive index and extinction coefficient spectrum diagram of the phase change material Ge2Sb2Te5 (GST) in the present invention. DETAILED DESCRIPTION

[0044] The invention relates to a complex amplitude dynamic modulation unit, comprising an excitation module and two or more modulation modules, wherein the modulation modules form a closed loop; the excitation module controls the modulation module to switch between a silent state (not excited by a signal) and an activated state (not excited by a signal).

[0045] Based on the complex amplitude dynamic modulation unit, the present invention also provides a complex amplitude dynamic modulation method, which solves the problems of fixed structure shape, inability to realize dynamic modulation, very difficult large-scale synchronous modulation, small amplitude modulation amplitude and phase modulation range, and quite limited spectral bandwidth. This method does not need to design different azimuth angles and opening angles, has a higher spectral bandwidth, is simpler to manufacture and design, is easier to operate the light field, and has a lower preparation cost. More importantly, it realizes a complex amplitude dynamic modulation technology that is easy to operate; the present invention also provides a complex amplitude dynamic modulator, including the above-mentioned annular modulation unit, and the resonant structure formed by the combination of such modulation units has a wide range and higher precision amplitude and phase modulation. The present invention lays a solid foundation for the large-scale commercial application of optical processing systems with fast time response, sensitive reaction, lower driving power, and better temperature stability.

[0046] The purpose, characteristics and advantages of the present invention will be explained through the following embodiments. It is worth noting that the embodiments are only typical examples of the technology of the present invention. Any technical solutions formed by equivalent replacement or equivalent transformation are within the scope of protection required by the present invention.

[0047] It should be noted that the modulation module described in this application can be a bulk structure or a thin film structure, etc., and its optical properties are changed by the outside world. When there is no signal excitation, it is in a silent state, and its modulation of light only produces optical effects based on its own optical properties; when there is signal excitation, it is in an activated state, and can further regulate the scattering, interference and diffraction of light, etc., thereby changing the amplitude and phase of light and other information. As common knowledge in the field, the materials that can be used are metals, semiconductors and polymers, such as Au, VO2, Sb2S3, etc.

[0048] The occupied position described in the present application is the position occupied by the modulation module in the silent state, and each occupied position includes at least one modulation module.

[0049] Example 1

[0050] In this embodiment, the Figure 3 The modulation modules are spliced ​​into Figures 4-5 The complex amplitude modulation unit. The state of the modulation module is controlled by an excitation module. In this embodiment, the modulation module is a thin film phase change material layer Ge2Sb2Te5 with a thickness of 200nm. The refractive index and extinction coefficient spectra of the phase change material in the crystalline and amorphous states are shown in FIG. Fig.12As shown; the excitation module includes electrodes ITO (30nm) located on the upper and lower sides of the modulation module, and an electrical signal output module, such as Figure 2 As shown, the electrical signal output module controls the electrodes to input voltage to the modulation module, each electrode is independent of each other, and no thermal / electrical crosstalk occurs between the electrodes, so that each modulation module undergoes independent dynamic conversion between the crystalline state and the amorphous state.

[0051] like Figures 4-5 As shown in FIG. 1 , the circular complex amplitude modulation unit is composed of 8 independent modulation modules connected end to end and arranged closely. Figure 4 As shown, the radius r of the outer circle is 35 μm, the width w of the ring is 5 μm, the opening angle α is 45°, and the azimuth angle θ is 67.5°.

[0052] This embodiment also specifically involves a complex amplitude dynamic modulation method, such as Figure 5 The eight independent modulation modules are numbered 1, 2, 3, 4, 5, 6, 7, and 8 in sequence, forming a circular ring structure. Assuming that the phase change material in the modulation module 1 in the initial state is crystalline, and the phase change materials in the remaining units are amorphous, to achieve independent amplitude modulation, it is only necessary to modulate the phase change material in the modulation module 8 to the crystalline state (activated state) and the phase change material in the modulation module 1 to the amorphous state (activated state), and the phase change materials in the remaining units remain in the amorphous state (quiet state), so that the C-shaped azimuth angle θ changes, while the opening angle α remains unchanged; to achieve independent phase modulation, it is only necessary to modulate the phase change materials in the modulation modules 8, 1 and 2 to the crystalline state, wherein the modulation modules 8 and 2 are in the activated state, and the phase change materials in the remaining units remain in the amorphous state (quiet state), so that the C-shaped opening angle α changes, while the azimuth angle θ remains unchanged, thereby achieving independent modulation of phase and amplitude; the current dynamic modulation is to apply voltages with different pulse widths and pulse numbers to the bottom electrode to cause the phase change material of the modulation module layer to undergo phase changes or produce different degrees of crystallization, the phase change speed reaches 30ns, and the number of transitions between phases reaches more than 5000 times, with faster response speed, simple control method and low cost.

[0053] Therefore, this embodiment greatly reduces the difficulty of the preparation process, saves a lot of time and production costs, and has a wide modulation range. It can simply control the phase state (quiescent state and activated state) and crystallinity (different degrees of activated state) of the phase change material to achieve independent dynamic modulation of the amplitude 0-1 and the phase 0-2π in the full range. The schematic diagram of the independent amplitude modulation effect under different crystallinity levels is shown in FIG. Figure 6 As shown in the figure, the schematic diagram of phase independent modulation effect under different crystallization degrees is as follows Figure 7As shown, it can be foreseen that, at a suitable wavelength, changing the degree of crystallization of the phase change material in the device structure will result in independent amplitude and phase modulation of several energy levels, and light field modulation can be achieved directly by controlling the voltage without going through complex device structure design and array design. The operation is simpler and the manufacturing cost is lower, while having the effects of higher precision and less noise.

[0054] Based on the characteristics of phase change materials, it can be foreseen in the art that any phase change material with crystalline and amorphous states, including but not limited to GST, Sb2S3, GeTe, Sb2Te3, Sb2Te, Ge 15 Sb 85 Etc., it can complete light field modulation in most environments and has a wide range of applications.

[0055] Example 2

[0056] The present invention designs a square ring complex amplitude dynamic modulation unit, the cross-sectional structure diagram of which is shown in FIG. Figure 8 As shown, it has a higher spectral bandwidth and is simpler to manufacture and design.

[0057] This square ring type complex amplitude dynamic modulation unit mainly includes an electrical signal output module, a modulation module (phase change material layer) and electrodes corresponding to the modulation modules. The electrode is ITO, 50nm thick, and the phase change material layer is Ge2Sb2Te5, 150nm thick. It is composed of 12 independent modulation modules connected end to end and arranged closely, and each modulation module is 20μm long and 5μm wide.

[0058] In this embodiment, a complex amplitude dynamic modulation method is also specifically involved. Different from the C-ring control method, this method can achieve a wider range of amplitude and phase modulation. The square ring complex amplitude dynamic modulation unit is composed of 12 independent modulation modules, which are numbered 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, and 12 in sequence. The initial states of all modulation modules are crystalline. This method can achieve complex amplitude dynamic control by regulating the size and position of the occupied position, that is, controlling 3, 4, 7, and 11 to be amorphous (activated state), and the remaining modulation modules to be crystalline (quiet state). The electrical signal output module is used to apply voltages with different pulse widths and pulse numbers to the bottom electrode to cause the phase change material of the modulation module layer to undergo phase changes or produce different degrees of crystallinity. It has a faster response speed and a simple control method with low cost.

[0059] Example 3

[0060] This embodiment adopts a circular complex amplitude modulation unit similar to that of Embodiment 1, and controls the modulation module through the electrical signal output module to obtain Fig. 9 The X-type resonant structure shown.

[0061] This X-type resonant structure can overcome the problem of limited tuning range of existing X-type complex amplitude modulation units due to rod length, limited crossing angle and fixed structure, solve the problems of mutual crosstalk between amplitude and phase information, and has a wider spectral tuning range and higher control accuracy.

[0062] Example 4

[0063] This embodiment uses a circular complex amplitude modulation unit similar to that of Embodiment 1 and an auxiliary modulation unit (composed of sectors 9 to 16) to form a resonant structure having a core-shell shape, such as Fig.10 As shown in the figure, the core part is composed of 8 fan-shaped auxiliary modulation sub-modules with a central angle of 45°, forming a large circular structure auxiliary modulation module; each sub-module is also independently controlled by partition, that is, through the control of the auxiliary excitation module, the silent state and activation state of each sub-module are independent of each other and do not interfere with each other.

[0064] The configuration of this embodiment better overcomes the DC noise and twin image problems of existing pure amplitude modulation and the serious speckle noise problem caused by existing pure phase modulation, and achieves the effect of complex amplitude modulation with higher precision and less noise.

[0065] This complex amplitude dynamic modulator is composed of a circular modulation unit and a circular auxiliary modulation unit, including an electrical signal output module, a modulation module (phase change material) and electrodes corresponding to the modulation modules. The electrode ITO is 45nm thick and the phase change material layer Sb2Te3 is 195nm thick. The circular modulation unit is composed of 8 independent modulation modules connected end to end and arranged closely, and are numbered 1, 2, 3, 4, 5, 6, 7, and 8 respectively. The radius r of the outer circle is 35μm, the width w of the ring is 5μm, and the initial state of all modulation modules is crystalline. The complex amplitude dynamic modulation method mentioned in Example 2 is used to control 4 and 8 to be amorphous (activated state) through the electrical signal output module, and the remaining modulation modules are crystalline (quiet state). The circular auxiliary modulation unit auxiliary modulation unit is also composed of 8 independent modulation modules arranged closely, which are numbered 9, 10, 11, 12, 13, 14, 15, and 16 respectively, and the initial state of all modulation modules is crystalline. The radius r is 20 μm, of which 9 and 14 are amorphous (activated state), and the remaining modulation modules are crystalline (quiet state). In this way, a better modulation effect is achieved.

[0066] Example 5

[0067] The present invention proposes a dual-circular complex amplitude dynamic modulator, which has the same center and different radii. The cross-sectional structure diagram is shown in FIG. Fig.11 As shown, a wide range of complex amplitude dynamic modulation can be achieved with higher accuracy and excellent effects of reducing noise.

[0068] This complex amplitude dynamic modulator is a double-ring complex amplitude modulator. Different from Example 1, it has a wider modulation effect and can achieve independent amplitude and phase modulation by controlling the azimuth and opening angle of the inner and outer rings. The complex amplitude modulator consists of a large ring and a small ring, wherein the large ring is formed by 8 independent modulation modules connected end to end and arranged closely, numbered 1, 2, 3, 4, 5, 6, 7, 8 in sequence, and the initial state of all modulation modules is crystalline, the outer circle radius is 60μm, and the ring width is 5μm. The small ring is also formed by 8 independent modulation modules connected end to end and arranged closely, numbered 9, 10, 11, 12, 13, 14, 15, 16 in sequence, and the initial state of all modulation modules is crystalline, the outer circle radius is 35μm, and the ring width is 5μm. By controlling the pulse width and energy provided by the electrical signal output module, modulation modules 4 and 8 in the large ring and modulation modules 9 and 13 in the small ring are controlled to be amorphous (activated state), and the remaining modulation modules are controlled to be crystalline (quiet state). The azimuth angle and opening angle are adjusted as needed, thereby achieving a wider range and more precise complex amplitude modulation.

[0069] Example 6

[0070] The present invention proposes a circular complex amplitude dynamic modulator with different modulation modules, the cross-sectional structure diagram of which is shown in FIG. Fig.12 As shown, it has a wider amplitude and phase modulation range.

[0071] The difference between this annular complex amplitude dynamic modulation unit with different modulation modules' widths and Example 1 is that the widths of the modulation modules are different, thereby achieving a higher precision modulation effect, and being able to achieve a wide range of amplitude and phase modulation by controlling the width, azimuth and opening angle of the modulation modules.

[0072] The annular complex amplitude dynamic modulation unit is composed of 8 independent modulation modules, which are numbered 1, 2, 3, 4, 5, 6, 7, and 8 in sequence. The outer circle radius of all modulation modules is 35μm, and the width of the ring is 5μm, 3μm, 7μm, 2.5μm, 6μm, 7μm, 4μm, and 10μm, respectively. The initial state of all modules is crystalline. The method can realize complex amplitude dynamic regulation by adjusting the size and position of the occupied position, that is, the modulation module 8 is converted into an amorphous state (activated state) by electrical excitation, and the remaining modulation modules are still in a crystalline state (quiescent state). The method has a wide complex amplitude modulation range and can realize full-range modulation of amplitude 0-1 and phase 0-π.

[0073] Example 7

[0074] The present invention proposes a circular complex amplitude dynamic modulator that controls the crystallization degree of the modulation module to achieve different order optical constants. The cross-sectional structure diagram is shown in FIG. Fig.13As shown in the figure, different color levels represent different degrees of complex amplitude modulation effects, which can directionally change the optical constants of the device, produce multi-order amplitude and phase modulation, and significantly improve the complex amplitude modulation range of the device.

[0075] Different from Example 1, this embodiment can also change the optical constant of the device by changing the number and width of electrical pulses. The annular modulation unit (phase change material Ge2Sb2Te5) in this embodiment is composed of 8 independent modulation modules connected end to end and arranged closely, which are numbered 1, 2, 3, 4, 5, 6, 7, 8, respectively. The radius r of the outer circle is 35μm, the width w of the annulus is 5μm, and the initial state of all modulation modules is crystalline. This method applies electrical excitations of pulse width of 40ns and pulse number of 10; pulse width of 40ns and pulse number of 20; pulse width of 5ns and pulse number of 10; pulse width of 5ns and pulse number of 20 to modulation modules 7; 8; 1 and 2 respectively, so that modulation modules 7, 8, 1 and 2 are in amorphous state (activated state), while the remaining modules are still in crystalline state (quiescent state). By utilizing the characteristics of the number of pulses and pulse width to produce intermediate states with different degrees of crystallinity, the multi-order optical constants of the incident light are generated, thereby realizing multi-order independent modulation of amplitude and phase. This modulation method uses electrical excitation to achieve optical constants of different orders. Compared with changing device manufacturing parameters such as film thickness, the modulation method is simpler, less expensive and has a wide range of complex amplitude modulation.

Claims

1. A complex amplitude dynamic modulation unit, characterized in that: The invention comprises n modulation modules, and the modulation modules form a closed loop structure, where n≥2; and further comprises: an excitation module for inputting an excitation signal to the modulation module to change the optical properties of the modulation module; The closed-loop structure is a circular ring structure, a square ring structure, a triangular ring structure or any other closed ring structure; Inputting excitation signals to some modulation modules through the excitation module makes some modulation modules in an activated state with signal excitation, while some modulation modules are in a silent state without signal excitation; dynamically adjusting the position and number of the modulation modules in the silent state by dynamically adjusting the excitation signal, so as to realize dynamic modulation of the complex amplitude of the incident light; The modulation modules undergo independent dynamic transitions between active and silent states.

2. The complex amplitude dynamic modulation unit according to claim 1, characterized in that: The modulation module is a phase change material; the excitation module includes an electrical signal output module and electrodes corresponding to the modulation module one by one, and electrical excitation is input to the modulation module; or the excitation module includes an optical signal output module, and optical excitation is input to the modulation module; or the excitation module includes a heat output module, and heat is input to the modulation module.

3. A complex amplitude dynamic modulation method, characterized in that: The complex amplitude dynamic modulation unit according to claim 1 is implemented by inputting an excitation signal to a part of the modulation modules through an excitation module, so that the part of the modulation modules is in an activated state with signal excitation, while the part of the modulation modules is in a silent state without signal excitation; by dynamically adjusting the excitation signal, the position and number of the modulation modules in the silent state are adjusted to achieve dynamic modulation of the complex amplitude of the incident light.

4. The complex amplitude dynamic modulation method according to claim 3, characterized in that: It also includes dynamically regulating the excitation signal and regulating the order optical constant of the modulation module in the activated state to achieve dynamic modulation of the complex amplitude of the incident light.

5. The complex amplitude dynamic modulation method according to claim 3, characterized in that: The modulation module is a phase change material layer; the excitation module includes an electrical signal output module and electrodes corresponding to the modulation modules one by one, and the electrical signal output module inputs electrical excitation to the modulation module through the electrodes, so that the modulation module undergoes independent dynamic conversion between an activated state and a silent state, or each modulation module undergoes dynamic conversion under the activated state of different order optical constants.

6. The complex amplitude dynamic modulation method according to claim 5, characterized in that: Part of the modulation module is controlled to be in a crystalline state, and the rest is controlled to be in an amorphous state, so as to obtain a C-shaped resonance structure; or part of the modulation module is controlled to be in an insulating phase, and the rest is controlled to be in a metallic phase, so as to obtain a C-shaped resonance structure.

7. The complex amplitude dynamic modulation method according to claim 6, characterized in that: The number of modulation modules in the crystalline state is adjusted to achieve independent modulation of the amplitude; or the position of the modulation modules in the crystalline state is adjusted to achieve independent modulation of the phase; Alternatively, the number of modulation modules in the isolation phase is adjusted to achieve independent modulation of the amplitude; or the position of the modulation modules in the isolation phase is adjusted to achieve independent modulation of the phase.

8. The complex amplitude dynamic modulation method according to claim 5, characterized in that: Some modulation modules are controlled to be in a crystalline state, and the modulation modules in the crystalline state are discontinuous; or some modulation modules are controlled to be in an insulating phase, and the modulation modules in the insulating phase are discontinuous.

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