WO2021056251A1

WO2021056251A1 - Tunable optical filtering apparatus

Info

Publication number: WO2021056251A1
Application number: PCT/CN2019/107806
Authority: WO
Inventors: 郭斌
Original assignee: 深圳市海谱纳米光学科技有限公司
Priority date: 2019-09-25
Filing date: 2019-09-25
Publication date: 2021-04-01
Also published as: CN114868068B; CN114868068A

Abstract

A tunable optical filtering apparatus, comprising a first transparent substrate (101) and a second transparent substrate (102) bonded with each other, wherein surfaces, facing each other, of the first transparent substrate (101) and the second transparent substrate (102) are respectively provided with a first mirror face (111) and a second mirror face (112) that are parallel to each other; the first transparent substrate (101) is provided with an elastic structure (201) that is distributed around the outside of the first mirror face (111); and the side of the elastic structure (201) that is away from the first transparent substrate (101) is bonded together with the second transparent substrate (102) by means of a bond. A mirror face chip, composed of the substrates and the mirror faces, and the elastic structure (201) are made, using a separate and heterogeneous material, into an FPI device driven by a capacitor, and the requirements of an FPI device design for the mechanical strength are met, such that the first mirror face (111) and the second mirror face (112) can maintain an extremely high smoothness. The fabrication of an optical mirror face and the assembly of the FPI device are both compatible with standardized micromachining, thereby facilitating mass production thereof.

Description

Adjustable optical filter device

Technical field

The invention relates to the field of filters, in particular to an adjustable optical filter device.

Background technique

The tunable optical filter formed by the Fabry-Perot cavity structure is a device based on MEMS (Micro-Electro-Mechanical-System) technology. The Fabry-Perot cavity is composed of two mirrors that can provide high reflectivity and one that can provide resonance. It is composed of a space cavity. The incident light is confined in the Fabry-Perot cavity to oscillate back and forth for multiple times and interfere. When the interfering light signal reaches a certain condition, it will be emitted, mainly by adjusting the length of the Fabry-Perot cavity or the cavity refractive index To change the resonance conditions to achieve the filtering effect. Devices made by MEMS technology have the advantages of easy integration with integrated circuits, small device size, low production cost, fast response speed, and easy mass production. Therefore, tunable Fabry-Perot cavity filter devices have received extensive attention and research.

Tunable filter devices (FPI) based on Fabry-Perot (French glass cavity) interference can be applied to miniature spectrometers and miniature or even miniature hyperspectral cameras. In the field of visible-near infrared (400-1000nm) hyperspectral imaging, compared to other solutions, Fabry-Perot cavity provides the simplest system structure and optical path, so it can greatly reduce the cost and volume of hyperspectral cameras.

FPI devices in the visible-near infrared range usually use optical glass (such as synthetic quartz glass) as a substrate, and form a mirror chip through optical and semiconductor processing, and then assemble two mirror chips and an external piezoelectric actuator to form a glass cavity The module, by adjusting the driving voltage of the piezoelectric actuator, can adjust the relative position between the two mirror chips, and then achieve different wavelengths in the gating spectrum. Due to the huge difference in mechanical characteristics between the piezoelectric actuator and the glass, there is a non-negligible deformation of the mirror chip after assembly, which is generally the warpage of the mirror. Therefore, it is usually necessary to use a very thick glass as a substrate to reduce the deformation. The result is the difficulty of glass substrate processing and the increase of the system volume, and it is difficult to achieve mass production in the way of assembling modules.

In addition, the current glass cavity devices formed by micromachining are mainly of bulk and surface technology types. The essential feature of the two processes is to form a cantilever structure on the substrate of the mirror structure itself, or the mirror film itself is the elastic support of the device. Thin-film devices cannot achieve large sizes (for example, more than 10mm), and the elastic structure and mirror surface of current bulk process devices are provided by the same substrate, resulting in intrinsic stress and deformation of the mirror surface affected by the elastic structure, due to the cantilever beam structure It takes up a lot of chip area and also limits the size of the mirror itself.

It can be seen that the current FPI devices in the visible-near-infrared range have some key problems that limit the commercial application of the technology itself, such as:

1. Large-size FPI devices have problems such as large size, mismatch of mechanical strength between external piezoelectric actuator and mirror chip, large size of the device, difficult processing, and inability to mass production.

2. The micro-machined FPI device has an elastic structure and cannot be isolated from the mirror surface, which leads to intrinsic stress and deformation.

Summary of the invention

In view of the above-mentioned problems, the embodiments of the present application provide a tunable optical filter device, which has a simple device structure and low processing difficulty, and is very suitable for mass production.

According to one aspect, the present invention discloses a tunable optical filter device, which includes a first transparent substrate and a second transparent substrate, on the mutually facing surfaces of the first transparent substrate and the second transparent substrate, respectively A first mirror surface and a second mirror surface parallel to each other are provided, the first transparent substrate is provided with an elastic structure distributed around the outside of the first mirror surface, and the side of the elastic structure away from the first transparent substrate is connected to the second mirror surface through a bonding compound. Two transparent substrates are bonded together.

Preferably, the elastic structure includes a silicon film. The silicon film and the first mirror are made of two separate and different materials on the first transparent substrate, so the mechanical properties can be improved.

Preferably, the first mirror surface and the second mirror surface are made of metal materials. The first mirror surface and the second mirror surface form an optical mirror surface, the material of which can be made of metal such as silver, which facilitates the formation of capacitor-driven electrodes.

Preferably, the first mirror surface and the second mirror surface respectively serve as the first electrode and the second electrode driven by the capacitor. The first mirror surface and the second mirror surface are made of metal, so they can be used as capacitor-driven electrodes after being energized, and the distance between the first mirror surface and the second mirror surface can be changed, the resonance condition can be changed, and the filtering effect can be achieved.

Preferably, the first mirror surface and the second mirror surface are distributed Bragg reflectors formed by superposing silicon, silicon dioxide and silicon. The distributed Bragg reflector can enhance the specular reflectivity.

Preferably, the first transparent substrate and the second transparent substrate are respectively provided with third electrodes and fourth electrodes distributed around the outer periphery of the first mirror surface and the second mirror surface facing each other. The third electrode and the fourth electrode are used as capacitor-driven electrodes to adjust the resonance of the mirror surface, and can also be used to fine-tune the tilt of the mirror surface.

Preferably, the third electrode and the fourth electrode are closer to the first mirror surface or the second mirror surface relative to the elastic structure. The third electrode and the fourth electrode are oppositely arranged on the side of the elastic structure and the bonding compound close to the first mirror surface or the second mirror surface.

Preferably, the third electrode and the fourth electrode are farther away from the first mirror surface or the second mirror surface than the elastic structure. The third electrode and the fourth electrode are oppositely arranged on the side of the elastic structure and the bonding compound away from the first mirror surface or the second mirror surface.

Preferably, the third electrode and the fourth electrode are closer to the first mirror surface or the second mirror surface relative to the elastic structure, and the first transparent substrate and the second transparent substrate are respectively provided with the first mirror surface and the second mirror surface. The fifth electrode and the sixth electrode facing each other around the outer periphery of the, the fifth electrode and the sixth electrode are farther away from the first mirror surface or the second mirror surface relative to the elastic structure. The third electrode, the fourth electrode, the fifth electrode, and the sixth electrode may also be arranged on both sides of the elastic structure and the bonding compound, respectively.

Preferably, a side of the first transparent substrate close to the elastic structure forms a cavity for accommodating the deformation and movement of the elastic structure. The cavity is conducive to the deformation of the elastic structure, and the mechanical strength of the mirror and the transparent substrate is much higher than that of the elastic structure. Therefore, after assembly, the optical mirror can maintain a very high flatness, without the need for a very thick substrate, and has a high level of flatness. The degree can be maintained during the operation of the device.

Preferably, a groove is provided on a side of the first transparent substrate close to the elastic structure, and the elastic structure covers the groove to form a cavity. The groove is provided on the substrate to facilitate processing, and the separation of the mirror surface and the elastic structure provides higher design flexibility for the FPI device. The same elastic structure can be applied to French glass cavity devices of different sizes (such as wafer level).

Preferably, the elastic structure and the first transparent substrate are connected by bonding. Several elastic structures are formed on the first transparent substrate through micromachining and bonding, and the process is simple and mature.

Preferably, the bonding method includes eutectic bonding, polymer bonding or anodic bonding. There can be multiple bonding methods to choose according to specific processes and scenarios.

Preferably, the material of the first transparent substrate and the second transparent substrate includes glass or sapphire. Glass or sapphire is easy to process to form devices of different sizes.

The embodiment of the present application discloses a tunable optical filter device, which includes a first transparent substrate and a second transparent substrate bonded to each other, on the surfaces of the first transparent substrate and the second transparent substrate facing each other A first mirror surface and a second mirror surface parallel to each other are respectively provided on the upper surface, the first transparent substrate is provided with an elastic structure distributed around the outside of the first mirror surface, and the side of the elastic structure away from the first transparent substrate passes through the bonding compound Bonded with the second transparent substrate. The mirror chip composed of the substrate and the mirror surface and the elastic structure are made of FPI devices driven by capacitors through separate and different materials, which meet the requirements of FPI device design in terms of mechanical strength, reduce intrinsic stress and deformation, and make the first mirror surface It maintains extremely high flatness with the second mirror surface, and does not require an extremely thick substrate, and can achieve high flatness even during device operation. The separate setting of the mirror chip and the elastic structure provides higher flexibility in the design of FPI devices, which can be made with more different materials and processes, and can be applied to French glass cavity devices of different sizes. The manufacture of optical mirrors and the assembly of FPI devices are compatible with standardized micro-machining, so they are suitable for mass production.

Description of the drawings

The drawings are included to provide a further understanding of the embodiments and the drawings are incorporated into this specification and constitute a part of this specification. The drawings illustrate the embodiments and together with the description serve to explain the principle of the present invention. It will be easy to recognize the other embodiments and the many expected advantages of the embodiments because they become better understood by quoting the following detailed description. The elements of the drawings are not necessarily in proportion to each other. The same reference numerals refer to corresponding similar parts.

FIG. 1 is a schematic cross-sectional view of a tunable optical filter device in an embodiment of the application;

2 is a schematic cross-sectional view I of the tunable optical filter device according to the first embodiment of the application;

3 is a schematic cross-sectional view II of the tunable optical filter device of the first embodiment of the application;

FIG. 4 is a schematic cross-sectional view III of the tunable optical filter device according to the first embodiment of the application;

5 is a schematic cross-sectional view of the tunable optical filter device according to the second embodiment of the application;

Figure 6 is a top view I of the tunable optical filter device in the embodiment of the application;

FIG. 7 is a top view II of the tunable optical filter device in the embodiment of the application.

detailed description

The application will be further described in detail below with reference to the drawings and embodiments. It can be understood that the specific embodiments described here are only used to explain the related invention, but not to limit the invention. In addition, it should be noted that, for ease of description, only the parts related to the relevant invention are shown in the drawings.

It should be noted that the embodiments in this application and the features in the embodiments can be combined with each other if there is no conflict. Hereinafter, the application will be described in detail with reference to the drawings and in conjunction with the embodiments.

As shown in FIG. 1, an embodiment of the present invention provides a tunable optical filter device, which includes a first transparent substrate 101 and a second transparent substrate 102. In a preferred embodiment, the first transparent substrate 101 The material of the second transparent substrate 102 and the second transparent substrate 102 can be selected from transparent materials such as glass or sapphire. Therefore, the first transparent substrate 101 and the second transparent substrate 102 can be selected from quartz glass wafers or alumina. Glass or sapphire is easy to process in industry to form FPI devices that meet different needs. A first mirror surface 111 and a second mirror surface 112 parallel to each other are respectively provided on the surfaces of the first transparent substrate 101 and the second transparent substrate 102 facing each other. The first mirror surface 111 and the second mirror surface 112 can be used as optical mirror surfaces. It is deposited on the surface of the first transparent substrate 101 and the second transparent substrate 102 by micromachining, and then etched to form corresponding patterns. The first mirror 111 and the second mirror 112 can be made of metal, dielectric or semiconductor materials. , Choose according to the actual needs of FPI device design. The first transparent substrate 101 is provided with elastic structures 201 distributed around the outside of the first mirror 111. The elastic structures 201 and the first transparent substrate 101 are connected by bonding. The elastic structures 201 can be bonded or etched. The method is formed on the surface of the first transparent substrate 101. This method is simple and mature, which is conducive to industrialized mass production. The side of the elastic structure 201 away from the first transparent substrate 101 is bonded to the second transparent substrate 102 through a bonding compound 202. A bonding compound 202 that can be used for the next step of bonding is formed on the elastic structure 201, which is beneficial for bonding the elastic structure 201 and the second transparent substrate 102 to realize the first transparent substrate 101 and the second transparent substrate 102. Connection.

In a specific embodiment, the elastic structure 201 includes a silicon film. The silicon thin film and the first mirror 111 are composed of two separate and different materials on the first transparent substrate 101. When the first transparent substrate 101 and the first mirror 111 constitute a movable mirror structure that is driven to move, Changing the distance between the first mirror 111 and the second mirror 112 to gate different wavelengths in the spectrum, the material separation of the elastic structure 201 and the movable mirror structure can overcome the problems of mechanical strength differences and reduce the intrinsic stress And strain, so the mechanical properties can be improved. In other optional embodiments, the elastic structure 201 can also select other materials to form a sheet structure. As shown in FIG. 1, a side of the first transparent substrate 101 close to the elastic structure 201 forms a cavity for accommodating the deformation and movement of the elastic structure 201. The cavity facilitates the deformation of the elastic structure 201, and the mechanical strength of the first mirror 111 and the first transparent substrate 101 is much higher than that of the elastic structure 201. Therefore, after assembly, the first mirror 111 and the second mirror 112 can be kept extremely high. The thickness of the first transparent substrate 101 and the second transparent substrate 102 does not need to be very thick, and the high flatness can be maintained during the operation of the device. In a preferred embodiment, a groove 203 is provided on the side of the first transparent substrate 101 close to the elastic structure 201, and the elastic structure 201 covers the groove 203 to form a cavity. The groove 203 is provided on the first transparent substrate 101 to facilitate processing. The separation of the first mirror 111 and the elastic structure 201 provides higher design flexibility for FPI devices. The same elastic structure 201 can be applied to different sizes (such as wafers). Level) of the French glass cavity device.

In a specific embodiment, the first mirror surface 111 and the second mirror surface 112 are used as optical mirror surfaces, and may be made of a metal material, a medium, or a semiconductor material.

Example one

As shown in FIG. 1, the first mirror surface 111 and the second mirror surface 112 are made of a metal material. In a preferred embodiment, the first mirror 111 and the second mirror 112 may be made of silver to form capacitor-driven electrodes. Therefore, the first mirror surface 111 and the second mirror surface 112 respectively serve as the first electrode and the second electrode driven by the capacitor. Since the first mirror 111 and the second mirror 112 are made of metal and have conductive properties, they can be used as capacitor-driven electrodes after being energized. The first and second electrodes can be changed by changing the magnitude of the voltage applied to the first and second electrodes. The distance between the mirror surface 111 and the second mirror surface 112 is used to change the resonance condition to achieve the filtering effect and obtain the light of the required wavelength.

In this case, the first transparent substrate 101 and the second transparent substrate 102 may also be respectively provided with third electrodes 301 and fourth electrodes which are distributed around the outside of the first mirror surface 111 and the second mirror surface 112 and face each other. 302. Apply voltage to the third electrode 301 and the fourth electrode 302 respectively to form a capacitor-driven driver to fine-tune the distance between the first transparent substrate 101 and the second transparent substrate 102 to avoid the first transparent substrate 101 Or the second transparent substrate 102 may be warped under the driving of the first electrode and the second electrode. In a preferred embodiment, as shown in FIGS. 2 and 3, the third electrode 301 may be arranged at a position closer to the first mirror surface 111 relative to the elastic structure 201, that is, between the elastic structure 201 and the first mirror surface 111, It can also be arranged at a position farther away from the first mirror 111 relative to the elastic structure 201, that is, around the outside of the elastic structure 201 far away from the first mirror 111, that is, around the outside of the elastic structure 201. Correspondingly, the fourth electrode 302 can be arranged at a position closer to the second mirror 112 relative to the elastic structure 201, that is, between the bonding compound 202 and the second mirror 112, or can be arranged at a position farther away from the elastic structure 201. The position of the second mirror surface 112 is set on the outer periphery of the side of the bonding compound 202 far away from the second mirror surface 112, that is, around the outer periphery of the bonding compound 202. At this time, the third electrode 301 and the fourth electrode 302 are oppositely arranged on one of the two sides of the elastic structure 201 and the bonding compound 202. In other optional embodiments, the third electrode 301 and the fourth electrode 302 may also be arranged on both sides of the elastic structure 201 and the bonding compound 202. In this case, the third electrode 301 is arranged between the elastic structure 201 and the first mirror 111 and the outer periphery of the elastic structure 201 on the side away from the first mirror 111, and the fourth electrode 302 is arranged between the bonding compound 202 and the second mirror 111. Between 112 and the outer periphery of the bonding compound 202 on the side away from the second mirror 112. The third electrode 301 and the fourth electrode 302 can be used to fine-tune the tilt of the first mirror surface 111 or the second mirror surface 112, so the distance between the first mirror surface 111 and the second mirror surface 112 is more controllable.

In other optional embodiments, in addition to providing the third electrode 301 and the fourth electrode 302 on one side of the elastic structure 201, the fifth electrode 303 and the sixth electrode 304 are also provided on the other side of the elastic structure. The third electrode 301 and the fourth electrode 302 are closer to the first mirror surface 111 or the second mirror surface 112 than the elastic structure 201, and the first transparent substrate 101 and the second transparent substrate 102 are respectively provided with the first mirror surface. The fifth electrode 303 and the sixth electrode 304 facing each other around the outer periphery of the 111 and the second mirror 112, and the fifth electrode 303 and the sixth electrode 304 are farther away from the first mirror 111 or the second mirror 112 relative to the elastic structure 201. The position of the third electrode 301, the fourth electrode 302, the fifth electrode 303, and the sixth electrode 304 and the magnitude of the applied voltage are related to the adjustment degree of the distance between the first mirror surface 111 and the second mirror surface 112. According to the requirements of the specific FPI device, the positions of the third electrode 301, the fourth electrode 302, the fifth electrode 303, and the sixth electrode 304 can be flexibly adjusted and set. The FPI device thus formed can be driven by a capacitive method, and the manufacture of the optical mirror surface and the assembly of the FPI device are compatible with standardized micro-machining and thus are suitable for mass production.

As shown in FIG. 5, the first mirror surface 111 and the second mirror surface 112 may also be a distributed Bragg reflector formed by superimposing silicon, silicon dioxide, and silicon. Distributed Bragg reflectors are arranged on the first transparent substrate 101 and the second transparent substrate 102 to enhance the specular reflectivity. In this case, at least the first transparent substrate 101 and the second transparent substrate 102 are respectively provided with third electrodes 301 and fourth electrodes 302 which are distributed around the outer periphery of the first mirror surface 111 and the second mirror surface 112 and face each other. . The third electrode 301 and the fourth electrode 302 are used as capacitor-driven electrodes to adjust the resonance of the first mirror 111 and the second mirror 112 to obtain light of a desired wavelength.

In a specific embodiment, the third electrode 301 may be arranged at a position closer to the first mirror 111 relative to the elastic structure 201, that is, between the elastic structure 201 and the first mirror 111, or may be arranged closer to the elastic structure 201. The position far away from the first mirror surface 111 is set at the outer periphery of the side of the elastic structure 201 far away from the first mirror surface 111, that is, around the outer periphery of the elastic structure 201. Correspondingly, the fourth electrode 302 can be arranged at a position closer to the second mirror 112 relative to the elastic structure 201, that is, between the bonding compound 202 and the second mirror 112, or can be arranged at a position farther away from the elastic structure 201. The position of the second mirror surface 112 is set on the outer periphery of the side of the bonding compound 202 far away from the second mirror surface 112, that is, around the outer periphery of the bonding compound 202. The third electrode 301 and the fourth electrode 302 are oppositely arranged on one of the two sides of the elastic structure 201 and the bonding compound 202.

In other optional embodiments, in addition to providing the third electrode 301 and the fourth electrode 302 on one side of the elastic structure 201, the fifth electrode 303 and the sixth electrode 304 may also be provided on the other side of the elastic structure. As shown in FIG. 5, the third electrode 301 and the fourth electrode 302 are closer to the first mirror surface 111 or the second mirror surface 112 relative to the elastic structure 201, and the first transparent substrate 101 and the second transparent substrate 102 are respectively provided There are fifth electrodes 303 and sixth electrodes 304 distributed around the outer periphery of the first mirror surface 111 and the second mirror surface 112 facing each other. The fifth electrode 303 and the sixth electrode 304 are farther away from the first mirror surface 111 or the elastic structure 201. The second mirror 112. The position of the third electrode 301, the fourth electrode 302, the fifth electrode 303, and the sixth electrode 304 and the magnitude of the applied voltage are related to the adjustment degree of the distance between the first mirror surface 111 and the second mirror surface 112. According to the requirements of the specific FPI device, the positions of the third electrode 301, the fourth electrode 302, the fifth electrode 303, and the sixth electrode 304 can be flexibly adjusted and set. The FPI device thus formed can be driven by a capacitive method, and the manufacture of the optical mirror surface and the assembly of the FPI device are compatible with standardized micro-machining and thus are suitable for mass production.

In a specific embodiment, both the first mirror surface 111 and the second mirror surface 112 can be deposited on the first transparent substrate 101 and the second transparent substrate 102 by means of plasma precipitation or chemical vapor deposition, respectively, and then formed by etching Related patterns. The elastic structure 201 is formed on the first transparent substrate 101 by bonding or etching. The bonding compound 202 is also arranged on the elastic structure 201 and the second transparent substrate 102 in a bonding manner. The bonding method includes eutectic bonding, polymer bonding or anodic bonding. Eutectic bonding is the use of metal as a transition layer to achieve the bonding between silicon and silicon. The surface requirements are not high, the bonding temperature is low, and the bonding strength is high; anodic bonding has a low bonding temperature, which is comparable to other processes. It has the advantages of good capacitance, high bonding strength and stability, and can be used for bonding between silicon/silicon substrates, non-silicon materials and silicon materials, and mutual bonding between glass, metals, semiconductors, and ceramics. According to the actual bonding surface technology and materials, a suitable bonding method can be selected to realize the bonding of the mirror chip. In a preferred embodiment, you can choose to deposit the first mirror surface 111 and the second mirror surface 112 on the first transparent substrate 101 and the second transparent substrate 102 respectively, and then respectively deposit the first mirror surface 111 and the second mirror surface 112 on the first transparent substrate 101 and the second transparent substrate 102 respectively. An elastic structure 201 and a bonding compound 202 are provided on the substrate 102 by bonding. Then, the first transparent substrate 101 provided with the elastic structure 201 and the second transparent substrate 102 provided with the bonding compound 202 are assembled together by bonding, and finally a mirror chip containing several silicon thin films is formed by dicing.

In a specific embodiment, as shown in FIG. 6 and FIG. 7, the elastic structure 201 may be a ring structure arranged around the outer periphery of the first mirror surface 111 and the second mirror surface 112, or it may be arranged in a shape with a certain pattern. structure. Similarly, the third electrode 301, the fourth electrode 302, the fifth electrode 303, and the sixth electrode 304 may also be arranged in a ring structure around the elastic structure 201, or may be arranged in a shape structure with a certain pattern. The positions and patterns of the elastic structure 201, the third electrode 301, the fourth electrode 302, the fifth electrode 303, and the sixth electrode 304 are diversified to meet the requirements of FPI devices of different shapes or different functions. In a preferred embodiment, as shown in FIG. 6, the elastic structure 201 is provided on a plurality of symmetrically distributed circular structures around the outside of the first mirror surface 111 and the second mirror surface 112, and the third electrode 301 and the fourth electrode 302 are respectively Four symmetrically distributed circular structures are arranged around the outer periphery of the elastic structure 201.

The specific implementation manners of this application are described above, but the protection scope of this application is not limited to this. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed in this application, and they should all be covered Within the scope of protection of this application. Therefore, the protection scope of this application should be subject to the protection scope of the claims.

In the description of this application, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "inner", "outer", etc. are based on the orientation or positional relationship shown in the drawings, and are only for It is convenient to describe the application and simplify the description, instead of indicating or implying that the device or element referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore cannot be understood as a limitation of the application. The word'comprising' does not exclude the presence of elements or steps not listed in the claims. The wording'a' or'one' in front of an element does not exclude the existence of a plurality of such elements. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used for improvement. Any reference signs in the claims should not be construed as limiting the scope.

Claims

An adjustable optical filter device, characterized in that it comprises a first transparent substrate and a second transparent substrate, which are respectively arranged on the mutually facing surfaces of the first transparent substrate and the second transparent substrate There are a first mirror surface and a second mirror surface parallel to each other, the first transparent substrate is provided with an elastic structure distributed around the outside of the first mirror surface, and a part of the elastic structure is away from the first transparent substrate. The side is bonded to the second transparent substrate through a bonding compound.
The tunable optical filter device according to claim 1, wherein the elastic structure comprises a silicon film.
The tunable optical filter device according to claim 1, wherein the first mirror surface and the second mirror surface are made of metal materials.
The tunable optical filter device according to claim 3, wherein the first mirror surface and the second mirror surface respectively serve as a first electrode and a second electrode driven by a capacitor.
The tunable optical filter device according to claim 1, wherein the first mirror surface and the second mirror surface are distributed Bragg reflectors formed by superimposing silicon, silicon dioxide, and silicon.
The tunable optical filter device according to any one of claims 1 to 5, wherein the first transparent substrate and the second transparent substrate are respectively provided with distributions on the first mirror surface and the second transparent substrate. The third electrode and the fourth electrode face each other on the outer periphery of the second mirror surface.
The tunable optical filter device according to claim 6, wherein the third electrode and the fourth electrode are closer to the first mirror surface or the second mirror surface relative to the elastic structure.
The tunable optical filter device according to claim 6, wherein the third electrode and the fourth electrode are farther away from the first mirror surface or the second mirror surface than the elastic structure.
The tunable optical filter device according to claim 6, wherein the third electrode and the fourth electrode are closer to the first mirror surface or the second mirror surface relative to the elastic structure, and the first transparent The substrate and the second transparent substrate are respectively provided with fifth and sixth electrodes which are distributed around the outside of the first mirror surface and the second mirror surface and face each other. The sixth electrode is farther away from the first mirror surface or the second mirror surface than the elastic structure.
The tunable optical filter device according to claim 1, wherein a side of the first transparent substrate close to the elastic structure forms a cavity for accommodating the deformation and movement of the elastic structure.
The tunable optical filter device according to claim 10, wherein a groove is provided on a side of the first transparent substrate close to the elastic structure, and the elastic structure covers the groove to form a groove.述cavity.
The tunable optical filter device according to claim 1, wherein the elastic structure and the first transparent substrate are connected by bonding.
The tunable optical filter device according to claim 1 or 12, wherein the bonding method includes eutectic bonding, polymer bonding or anodic bonding.
The tunable optical filter device according to claim 1, wherein the material of the first transparent substrate and the second transparent substrate comprises glass or sapphire.