Modulation module, optical modulation device, and optical apparatus

Abstract

The invention provides a modulation module, which is used for an optical modulation device and comprises a substrate and a modulation interface. The modulation interfaces are formed on the surface of one side of the substrate, each modulation interface is used for receiving incident light, and the modulation interfaces are used for changing the phase and / or polarization direction of the incident light. Wherein the modulation interface comprises a plurality of modulation areas, and the degrees, used for changing the phase and / or polarization direction of the incident light, of the modulation areas are the same or different. The invention further provides an optical modulation device applying the modulation module and an optical device applying the optical modulation device.

Description

Technical Field

[0001] This application relates to the field of metasurfaces, and more particularly to a modulation module, an optical modulation device including the above-mentioned modulation module, and an optical device using the optical modulation device. Background Technology

[0002] In the field of optical design, phase retarders or polarizing elements are typically added to change the phase and polarization direction of light; scanning micromirrors are usually added to deflect light; and lenses or freeform mirrors are usually added to eliminate aberrations or chromatic aberrations. However, the introduction of phase retarders, polarizing elements, rotating mirrors, lenses, or freeform mirrors will affect the size of the optical device and will also increase the power consumption of the optical device. Summary of the Invention

[0003] The first aspect of this application provides a modulation module for an optical modulation device, comprising:

[0004] Substrate; and

[0005] A modulation interface is formed on one side surface of the substrate, each modulation interface is used to receive incident light, and the modulation interface is used to change the phase and / or polarization direction of the incident light;

[0006] The modulation interface includes multiple modulation regions, each of which is used to change the phase and / or polarization direction of the incident light to the same or different degrees.

[0007] The modulation module provided in this application provides a modulation module with multiple modulation regions on the modulation interface. The nanostructures of the multiple modulation regions are different from each other. When the incident light passes through different modulation regions, the phase and / or polarization direction of the incident light can be changed more easily according to the usage requirements. When the optical modulation device is applied to an optical device, the incident light can be controlled more easily, which is beneficial to reducing the size of the optical device and reducing the aberrations and chromatic aberrations of the optical device.

[0008] In one embodiment, each modulation region is provided with multiple raised nanostructures, and the nanostructures of the multiple modulation regions are different from each other. In another embodiment, the nanostructures of each modulation region are arranged irregularly on the substrate.

[0009] In one embodiment, the modulation interface is used to transmit the incident light, and the modulation module modulates the incident light into transmitted light, the phase and / or polarization direction of the transmitted light being different from that of the incident light.

[0010] In one embodiment, the modulation interface modulates the incident light into reflected light, the phase and / or polarization direction of which is different from that of the incident light.

[0011] A second aspect of this application provides an optical modulation device, comprising:

[0012] The subject; and

[0013] One or more modulation modules as described in any of the above embodiments.

[0014] The optical modulation device provided in this application provides one or more modulation modules as described in any of the above embodiments. The nanostructures of the multiple modulation regions of the multiple modulation modules are different from each other. When the incident light passes through different modulation regions, the phase and / or polarization direction of the incident light can be changed more conveniently according to the usage requirements. When the optical modulation device is applied to an optical device, the incident light can be controlled more conveniently, which is beneficial to reducing the size of the optical device and reducing the aberrations and chromatic aberrations of the optical device.

[0015] In one embodiment, each of the modulation regions is provided with a plurality of protruding nanostructures. When there are multiple modulation modules, the surfaces of all the modulation modules having the nanostructures have the same orientation and are arranged sequentially along the optical path of the incident light, so that the incident light passes through each of the modulation modules sequentially.

[0016] In one embodiment, the nanostructures of each modulation module are arranged irregularly on the substrate.

[0017] In one embodiment, when there are multiple modulation modules, at least one of the modulation modules has a side surface with the nanostructure for reflecting the incident light.

[0018] In one embodiment, when there are multiple modulation modules, the optical modulation device includes a first modulation module, a second modulation module, and a third modulation module, wherein the first modulation module, the second modulation module, and the third modulation module are arranged at equal intervals in sequence.

[0019] The first modulation module receives the incident light and modulates the incident light into a first transmitted light, wherein the angle of the first transmitted light is deflected by 1°-6° relative to the angle of the incident light;

[0020] The second modulation module receives the first transmitted light and modulates the first transmitted light into a second transmitted light, wherein the angle of the second transmitted light is deflected by 3°-8° relative to the angle of the first transmitted light.

[0021] The third modulation module receives the second transmitted light and modulates it into a third transmitted light, wherein the angle of the third transmitted light is deflected by 5°-10° relative to the angle of the second transmitted light.

[0022] A third aspect of this application provides an optical device, comprising:

[0023] A light source, used to emit incident light;

[0024] A transmitting system for receiving the incident light emitted from the optical modulator and for emitting the incident light into free space;

[0025] A receiving system for receiving the incident light reflected back from the free space, wherein the number of modulation regions is the same as the number of the receiving system; and

[0026] The optical modulation device described in any of the above embodiments is used to receive the incident light;

[0027] The optical modulation device is used to change the phase and / or polarization direction of the incident light.

[0028] The optical device provided in this application embodiment can conveniently control the incident light by setting the light modulation device described in any of the above embodiments, which is beneficial to reducing the size of the optical device and reducing the aberrations and chromatic aberrations of the optical device. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the structure of the optical modulation device in Embodiment 1 of this application.

[0030] Figure 2 This is a schematic diagram of the structure of a modulation module reflecting incident light according to an embodiment of this application.

[0031] Figure 3 This is a schematic diagram of the structure of the modulation region according to an embodiment of this application.

[0032] Figure 4 This is a schematic diagram of the structure of the optical modulation device in Embodiment 2 of this application.

[0033] Figure 5 This is a schematic diagram of the structure of an optical modulation device according to an embodiment of the present application, which includes three modulation modules.

[0034] Figure 6 for Figure 5 A top view of the three modulation modules.

[0035] Figure 7 This is a schematic diagram of the structure of a modulation module reflecting incident light in Embodiment 2 of this application.

[0036] Figure 8 This is a schematic diagram of the structure of an optical device according to an embodiment of this application.

[0037] Figure 9 A schematic diagram of the structure of a lidar according to an embodiment of this application.

[0038] Explanation of key component symbols:

[0039] Optical modulation devices 100, 200

[0040] Modulation module 1

[0041] Modulation interface 2

[0042] Modulation region 10

[0043] Nanostructure 13

[0044] Substrate 3

[0045] First modulation module 1a

[0046] Second modulation module 1b

[0047] Third modulation module 1c

[0048] Optical device 300

[0049] Light source 301

[0050] LiDAR 500

[0051] Launch System 501

[0052] Collimation Module 501a

[0053] Receiver System 503

[0054] Optical Amplifier 503a

[0055] 503b photoelectric converter

[0056] External object 505

[0057] Incident light LR

[0058] Transmitted light LT

[0059] First transmitted light LT1

[0060] Second transmitted light LT2

[0061] Third transmitted light LT3

[0062] Reflected light LF

[0063] The following detailed description, in conjunction with the accompanying drawings, will further illustrate the present invention. Detailed Implementation

[0064] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments.

[0065] Please refer to the following: Figure 1 , Figure 2 and Figure 3 The modulation module 1 of this application embodiment is used in an optical modulation device 100 (200), including a modulation interface 2 and a substrate 3. The modulation interface 2 is formed on one side surface of the substrate 3, and each modulation interface 2 is used to receive incident light LR, and the modulation interface 2 is used to change the phase and / or polarization direction of the incident light LR. The modulation interface 2 includes a plurality of modulation regions 10, and each modulation region 10 is used to change the phase and / or polarization direction of the incident light LR to the same or different degrees. Each modulation region 10 is provided with a plurality of protruding nanostructures 13, and the nanostructures 13 of the plurality of modulation regions 10 are different from each other.

[0066] In this embodiment, modulation module 1 can be used to transmit incident light LR. Modulation module 1 modulates the incident light LR into transmitted light LT, the phase and / or polarization direction of the transmitted light LT being different from that of the incident light LR. Please refer to [link to documentation]. Figure 2 In other embodiments, the modulation module 1 has a side surface with nanostructure 13 that can be used to reflect incident light LR. The modulation module 1 modulates the incident light LR into reflected light LF, and the phase and / or polarization direction of the reflected light LF is different from that of the incident light LR.

[0067] Please see Figure 3 The modulation interface 2 includes multiple modulation regions 10, each modulation region 10 having multiple nanostructures 13, and the nanostructures 13 of the multiple modulation regions 10 are different from each other. Each modulation region 10 is used to change the phase and / or polarization direction of the incident light LR to the same or different degrees. For example, in this embodiment, the modulation interface 2 includes three modulation regions 10, each modulation region 10 having a different shape of nanostructure 13, and the arrangement of the nanostructures 13 of each modulation region 10 on the substrate 3 is irregular. In other embodiments, the modulation interface 2 may also include two, four, or more modulation regions 10. In other embodiments, the material and / or shape of the nanostructures 13 of the multiple modulation regions 10 may be different from each other, depending on the application requirements, and this application does not impose any limitations.

[0068] The modulation module 1 provided in this application embodiment has multiple modulation regions 10 on a modulation interface 2. The nanostructures 13 of the multiple modulation regions 10 are different from each other. When the incident light LR passes through different modulation regions 10, the phase and / or polarization direction of the incident light LR can be changed relatively easily according to the usage requirements.

[0069] Please refer to the following: Figure 1Specifically, the material of substrate 3 is silicon. Using silicon as the material of substrate 3 has the advantages of high conductivity and low cost. Since the material of substrate 3 depends on the overall application environment of the optical modulation device 100 (200), in other embodiments, the substrate material of substrate 3 may also be indium phosphide, silicon nitride, or silicon-based optoelectronics, and this application does not impose any restrictions.

[0070] In this embodiment, the shape of the nanostructure 13 is a cuboid. In other embodiments, the shape of the nanostructure 13 can also be any of the following polyprism shapes: sphere, cylinder, triangular prism, or square prism. The resonant wavelength, resonant wavelength width, reflection characteristics, absorption characteristics, and transmission characteristics of light after passing through the nanostructure 13 can be changed according to the material, shape, and arrangement of the nanostructure 13. The material of the nanostructure 13 can be a metallic material with high conductivity and capable of inducing surface plasmon excitation. For example, it can be formed from at least one metal such as copper (Cu), aluminum (Al), nickel (Ni), or iron (Fe), or from an alloy including at least one of the metals. In addition, the material of the nanostructure 13 can also be a commonly used linear electro-optic material, such as potassium dihydrogen phosphate (KDP), ammonium dihydrogen phosphate (ADP), lithium niobate (LiNbO), lithium iodate (LiIO), etc., which are crystals without centrosymmetry. In other embodiments, the material of the nanostructure 13 can also be a piezoelectric material, such as quartz crystal, lithium gallium oxide, lithium germanate, titanium germanate, and iron transistors such as lithium niobate and lithium tantalate. The material of the nanostructure 13 is not limited to thermo-optical materials, piezoelectric materials, or electro-optical materials.

[0071] In this embodiment, low-temperature deep etching of the silicon nanostructure 13 can be performed using various etching mask materials such as polymers, chromium (Cr), silica, and Cr-monomer polymers. Since direct hard masks using Cr and silica are key factors limiting the achievement of aspect ratios, and etching selectivity affects the limitations of polymer masks, Cr exhibits the same high selectivity to polymer masks as Cr, reducing the over-cutting introduced by direct hard masks. By optimizing etching parameters, each nanostructure 13 is processed onto one side surface of the substrate 3. Other processing methods can also be used in other embodiments, and this application is not limiting.

[0072] Please see Figure 4The optical modulation device 100 (200) of this application embodiment includes a body (not shown) and one or more modulation modules 1 as described in any of the above embodiments. In this embodiment, the optical modulation device 200 includes multiple modulation modules 1. All modulation interfaces 2 have the same orientation of the surface with nanostructure 13 and are arranged sequentially along the optical path of the incident light LR, so that the incident light LR passes through each modulation module 1 sequentially. In this embodiment, the modulation module 1 can also be used to transmit the incident light LR, modulating the incident light LR into transmitted light LT, the phase and / or polarization direction of the transmitted light LT being different from that of the incident light LR; in other embodiments, the side surface of the modulation module 1 with the nanostructure 13 can be used to reflect the incident light LR, modulating the incident light LR into reflected light (not shown), the phase and / or polarization direction of the reflected light being different from that of the incident light LR. When there are multiple modulation modules 1, at least one of the modulation modules 1 has the side surface with the nanostructure for reflecting the incident light. Please refer to Figure 1 and Figure 2 In other embodiments, the optical modulation device 100 includes a modulation module 1. The body may include a power supply module (not shown) that can be used to provide voltage to the modulation module.

[0073] Please refer to the following: Figure 5 and Figure 6 In this embodiment, the optical modulation device 200 includes three modulation modules 1: a first modulation module 1a, a second modulation module 1b, and a third modulation module 1c, which are arranged sequentially at equal intervals. The nanostructures 13 of each modulation module 1 have different shapes, and their arrangement on the substrate 3 is irregular. In this embodiment, the nanostructure 13 of modulation module 1a is cuboid, the nanostructure 13 of the middle modulation module 1b is triangular prism, and the nanostructure 13 of modulation module 1c is cylindrical. The first modulation module 1a receives incident light LR and modulates it into a first transmitted light LT1, the angle of which is deflected by 1°-6° relative to the angle of the incident light LR. The second modulation module 1b receives the first transmitted light LT1 and modulates it into a second transmitted light LT2, the angle of which is deflected by 3°-8° relative to the angle of the first transmitted light LT1. The third modulation module 1c receives the second transmitted light LT2 and modulates it into a third transmitted light LT3, the angle of which is deflected by 5°-10° relative to the angle of the second transmitted light LT2. For further details, please refer to [link to relevant documentation]. Figure 7In other embodiments, when there are multiple modulation modules 1, the optical modulation device 200 may also include at least one modulation module 1 with a nanostructure on one side surface for reflecting the incident light LR. The specific application depends on the usage requirements and is not limited thereto.

[0074] In other embodiments, the optical modulation device 200 may also include two, four, or more modulation modules 1. When there are multiple modulation modules 1, the materials and / or shapes of the nanostructures 13 of the multiple modulation modules 1 may be different. The shape of the nanostructures 13 may also be any of the following polyprism shapes: sphere, cylinder, triangular prism, or quadrangular prism. The arrangement of the nanostructures 13 of each modulation module 1 on the substrate 3 may also be irregular, depending on the application requirements, and this application does not impose any restrictions.

[0075] The optical modulation device 200 provided in this application embodiment arranges multiple nanostructures 13 with the same orientation of modulation modules 1 in sequence, so that the incident light LR passes through each modulation module 1 in sequence. The phase and / or polarization direction of the incident light LR can be changed more conveniently according to the usage requirements. When the optical modulation device 100 is applied to an optical device, the control of the incident light LR can be realized more conveniently, which is beneficial to reducing the size of the optical device and reducing the aberration and chromatic aberration of the optical device.

[0076] Please see Figure 8 This application also provides an optical device 300, including a light source 301 and a light modulation device 100 (200) of any of the above embodiments. The light source 301 is used to emit incident light LR. The light modulation device 100 (200) is used to receive the incident light LR emitted by the light source 301. The light modulation device 100 (200) is used to change the phase and / or polarization direction of the incident light LR. The optical device 300 can be a virtual reality head-mounted display device, an augmented reality head-mounted display device, or a head-up display device; this application is not limited thereto. For example, the optical device 300 can be an optical ranging device. The optical ranging device can be applied to bicycles, ships, automobiles, and airplanes, etc. In addition, the optical ranging device can be used in applications such as radar, obstacle avoidance, 3D printing, image display, and free-space optical communication.

[0077] The optical device 300 provided in this application embodiment can easily and conveniently change the phase and / or polarization direction of the incident light LR by applying the above-mentioned optical modulation device 100 (200), which is beneficial to reducing the volume of the optical device 300 and reducing the aberration and chromatic aberration of the optical device 300.

[0078] Please see Figure 9In one embodiment, the optical device 300 is a lidar 500, which also includes a transmitting system 501 and a receiving system 503. The transmitting system 501 includes a collimation module 501a for focusing and collimating the incident light LR emitted from the light source 301. The incident light LR then passes through an optical modulator 100 (200). The optical modulator 100 (200) changes the phase and / or polarization direction of the incident light LR.

[0079] The transmitting system 501 receives the incident light LR emitted from the optical modulator 100 (200) and emits the incident light LR into free space. After being emitted into free space, the incident light LR emitted from the transmitting system 501 is reflected by an external object 505. The receiving system 503 receives the incident light LR reflected back from free space. The number of modulation regions 10 is the same as the number of receiving systems 503. The receiving system 503 may include an optical amplifier 503a and a photoelectric converter 503b. The optical amplifier 503a amplifies the optical signal of the incident light LR and converts the incident light LR from an optical signal to an electrical signal through the photoelectric converter, thereby facilitating signal processing and data conversion, and facilitating further control and calculation. The lidar 500 provided in this application embodiment, by applying the above-mentioned optical modulator 100 (200), can more easily adjust the deflection angle of the incident light LR, which is beneficial to reducing the size of the lidar 500 and reducing the power consumption of the lidar 500.

[0080] The above embodiments are only used to illustrate the technical solutions of this application and are not intended to limit it. Although this application has been described in detail with reference to the above preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions to the technical solutions of this application should not depart from the spirit and scope of the technical solutions of this application.

Claims

1. A modulation module for use in an optical modulation device, characterized in that, include: substrate; as well as A modulation interface is formed on one side surface of the substrate, each modulation interface is used to receive incident light, and the modulation interface is used to change the phase and / or polarization direction of the incident light; The modulation interface includes multiple modulation regions, each of which is used to change the phase and / or polarization direction of the incident light to the same or different degrees.

2. The modulation module as described in claim 1, characterized in that, Each of the modulation regions is provided with multiple protruding nanostructures, and the nanostructures of the multiple modulation regions are different from each other.

3. The modulation module as described in claim 2, characterized in that, The nanostructures of each modulation region are arranged irregularly on the substrate.

4. The modulation module as described in claim 1, characterized in that, The modulation interface is used to transmit the incident light, and the modulation module modulates the incident light into transmitted light, the phase and / or polarization direction of which is different from that of the incident light.

5. The modulation module as described in claim 1, characterized in that, The modulation interface modulates the incident light into reflected light, the phase and / or polarization direction of which are different from those of the incident light.

6. An optical modulation device, characterized in that, include: ontology; as well as One or more modulation modules as described in any one of claims 1 to 5.

7. The optical modulation device as described in claim 6, characterized in that, Each modulation region is provided with multiple protruding nanostructures. When there are multiple modulation modules, the surfaces of all modulation modules with the nanostructures have the same orientation and are arranged sequentially along the optical path of the incident light, so that the incident light passes through each modulation module sequentially.

8. The optical modulation device as described in claim 7, characterized in that, The nanostructures of each modulation module are arranged irregularly on the substrate.

9. The optical modulation device as described in claim 7, characterized in that, When there are multiple modulation modules, at least one of the modulation modules has a side surface with the nanostructure for reflecting the incident light.

10. The optical modulation device as described in claim 6, characterized in that, When there are multiple modulation modules, the optical modulation device includes a first modulation module, a second modulation module, and a third modulation module, wherein the first modulation module, the second modulation module, and the third modulation module are arranged at equal intervals in sequence. The first modulation module receives the incident light and modulates the incident light into a first transmitted light, wherein the angle of the first transmitted light is deflected by 1°-6° relative to the angle of the incident light; The second modulation module receives the first transmitted light and modulates the first transmitted light into a second transmitted light, wherein the angle of the second transmitted light is deflected by 3°-8° relative to the angle of the first transmitted light. The third modulation module receives the second transmitted light and modulates it into a third transmitted light, wherein the angle of the third transmitted light is deflected by 5°-10° relative to the angle of the second transmitted light.

11. An optical device, characterized in that, include: A light source, used to emit incident light; A transmitting system for receiving the incident light emitted from the optical modulator and for emitting the incident light into free space; A receiving system for receiving the incident light reflected back from the free space, wherein the number of modulation regions is the same as the number of the receiving system; as well as The optical modulation device according to any one of claims 6 to 10 is used to receive the incident light; The optical modulation device is used to change the phase and / or polarization direction of the incident light.

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