Angle scanning tuning type spectrum sensor based on double rotating shafts and application thereof

Abstract

The invention discloses an angle scanning tuning type spectrum sensor based on double rotating shafts and application of the angle scanning tuning type spectrum sensor. The sensor comprises a spectrum detection unit which is installed on a first carrier, is used for receiving incident light, and comprises a detector and an angle sensitive structure arranged on the detector; the first carrier is rotatably connected to the second carrier through a first rotating shaft and can rotate around the first rotating shaft relative to the direction of the incident light; and the second carrier can drive the spectrum detection unit and the first carrier to rotate around the second rotating shaft relative to the incident light direction. Wherein the first rotating shaft and the second rotating shaft are arranged on a reference plane and are parallel to each other or perpendicular to each other; the polarization direction of the incident light is parallel to the reference plane, and the included angles between the incident light and the first rotation axis and the second rotation axis are both larger than 0 degree. According to the invention, the working wavelength range of spectrum detection can be effectively enlarged.

Description

Technical Field

[0001] The present application relates to a spectral sensor, specifically to an angle-scanning tuning spectral sensor based on a double rotating shaft and its application in spectral analysis, belonging to the technical field of optoelectronic devices. Background Art

[0002] A scanning spectral detection chip can be based on one or a small number of detection units combined with a tuning dispersion unit, and realize spectral detection through sequential spectral sampling, thereby effectively reducing the device complexity and cost. However, various on-chip integrated dispersion tuning technologies, such as tuning optical resonance by electro-optic / thermo-optic / birefringence and other effects, usually have limited wavelength tuning ranges, resulting in a narrow working wavelength range for the scanning spectral detection chip. Summary of the Invention

[0003] The main purpose of the present application is to provide an angle-scanning tuning spectral sensor based on a double rotating shaft and its application, so as to overcome the deficiencies of the prior art.

[0004] To achieve the foregoing invention purpose, the technical solutions adopted in the present application include:

[0005] In a first aspect of the present application, an angle-scanning tuning spectral sensor based on a double rotating shaft is provided, which includes:

[0006] A spectral detection unit, installed on a first carrier, for receiving incident light, and the spectral detection unit includes a detector and an angle-sensitive structure arranged on the detector;

[0007] The first carrier is rotatably connected to a second carrier via a first rotation axis and can rotate relative to the incident light direction around the first rotation axis to change the incident angle;

[0008] The second carrier can drive the spectral detection unit and the first carrier to rotate relative to the incident light direction around a second rotation axis to change the incident angle;

[0009] Wherein, both the first rotation axis and the second rotation axis are arranged in a reference plane, and the included angle formed by the first rotation axis and the second rotation axis is 0° or 90°; the polarization direction of the incident light is parallel to the reference plane, and the included angles formed with the first rotation axis and the second rotation axis are both greater than 0° and less than 90°.

[0010] Furthermore, the resonance absorption or transmission spectrum of the angle-sensitive structure can change with the change of the incident angle. That is, the angle-sensitive structure transmits or absorbs light of different wavelengths at different incident angles.

[0011] Further, by rotating the first carrier about the first rotation axis and / or rotating the second carrier about the second rotation axis, the spectral detection unit can perform angular scanning relative to the incident light direction.

[0012] In one embodiment, the first rotation axis and the second rotation axis are parallel to each other and perpendicular to the polarization direction of the incident light, and the angle-sensitive structure includes a one-dimensional grating structure or a two-dimensional grating structure.

[0013] More preferably, the first rotation axis and the second rotation axis are coaxially arranged.

[0014] More preferably, the angle-sensitive structure includes a one-dimensional grating structure.

[0015] In one embodiment, the first rotation axis is perpendicular to the second rotation axis, and the angle-sensitive structure includes a two-dimensional grating structure.

[0016] Further, the included angle between the polarization direction of the incident light and the second rotation axis is 30° to 60°.

[0017] Further, the two-dimensional grating structure has a first grating period and a second grating period in two orthogonal directions respectively, wherein the first grating period direction is parallel to the first rotation axis, and the second grating period direction is parallel to the second rotation axis.

[0018] In one embodiment, the detector includes a photodetector or a photothermal detector, and is not limited thereto. For example, it can also be other detectors capable of performing photoelectric conversion.

[0019] In one embodiment, the detector is integrally arranged with the angle-sensitive structure. Further, the angle-sensitive structure can be a part of the corresponding detector or integrated above the corresponding detector. In some cases, the detector can be integrally arranged with the angle-sensitive structure.

[0020] Exemplarily, the detector in the spectral detection unit includes a semiconductor material, and a one-dimensional or two-dimensional semiconductor grating is integrally formed on the surface of the semiconductor material. The angle-sensitive structure includes a one-dimensional or two-dimensional semiconductor grating and a metal material coated on the one-dimensional or two-dimensional semiconductor grating, and the metal material forms a Schottky contact with the one-dimensional or two-dimensional semiconductor grating. Among them, the semiconductor material can be selected from, but not limited to, III-V group semiconductor materials such as GaN and InGaAs, or other semiconductor materials such as crystalline silicon.

[0021] Exemplarily, the angle-sensitive structure includes a one-dimensional or two-dimensional dielectric grating disposed on the detector and a metal material coated on the one-dimensional or two-dimensional dielectric grating. The one-dimensional or two-dimensional dielectric grating is formed of a dielectric material. Among them, the dielectric material may be selected from, but not limited to, inorganic dielectric materials or organic dielectric materials such as silicon dioxide (SiO2), silicon nitride (SiN), aluminum nitride (AlN), hafnium oxide, magnesium fluoride, or polymethyl methacrylate.

[0022] In some cases, the thickness of the metal material coated on the one-dimensional or two-dimensional semiconductor or dielectric grating is greater than 20 nm and less than 100 nm. The metal material may be selected from, but not limited to, metals or their alloys such as gold, platinum, silver, copper, aluminum, or titanium.

[0023] In some cases, the detector can be directly formed by using a substrate. For example, an Si substrate material can be used as the photoelectric response material of the detector, and a metal-Si Schottky detector can be directly formed by processing it using silicon technology. Or, a photoelectric response material can also be introduced by means of transfer, bonding, or epitaxial growth on the surface of the substrate, and then a detector (such as graphene, Ge, etc.) can be fabricated on the substrate using semiconductor device processes. The substrate can be a part of the active region of the detector or can only be used as a substrate. Or, the substrate can also be used as the substrate described below, and a detector that has been independently fabricated (such as InGaAs, Si, HgTe, etc. detectors) can be mounted on the substrate by means of chip bonding, etc. The substrate and the detector are independent of each other and can be interconnected through conductive lines, etc.

[0024] In one embodiment, the angle-scanning and tuning type spectral sensor includes a substrate, the substrate includes a fixed part, a first rotatable part, a second rotatable part, a first rotation axis, and a second rotation axis. The first rotatable part and the second rotatable part are the first carrier and the second carrier respectively, and the second rotatable part is rotatably connected to the fixed part through the second rotation axis.

[0025] Further, the surface of the fixed part is parallel to the reference plane.

[0026] Further, the angle-scanning and tuning type spectral sensor has at least a first state and a second state. In the first state, the surfaces of the first rotatable part and the second rotatable part are both parallel to the reference plane, while in the second state, the angle formed by the surface of at least one of the first rotatable part and the second rotatable part and the reference plane is greater than 0° and less than 90°.

[0027] In some cases, the fixed part and the second rotatable part may both have a frame structure. The first rotatable part is rotatably mounted within the frame structure of the second rotatable part via a first rotation axis. The second rotatable part is rotatably mounted within the frame structure of the fixed part via a second rotation axis.

[0028] Furthermore, the material of the substrate may be selected from silicon or silicon on insulator (SOI), etc., and is not limited thereto. Exemplarily, the substrate may be a device that rotates about an axis fabricated on silicon or SOI based on MEMS technology, such as a silicon micro-mirror.

[0029] Furthermore, the spectral detection unit has a first working electrode and a second working electrode. The first working electrode and the second working electrode are electrically connected to a first lead electrode and a second lead electrode via a first electrode wiring and a second electrode wiring respectively. The first electrode wiring extends at least along the first rotation axis from the first rotatable part to the fixed part, and the second electrode wiring extends at least along the second rotation axis from the second rotatable part to the fixed part. The first lead electrode and the second lead electrode are respectively disposed on the fixed part. With this design, the internal structure of the spectral sensor can be made more concise and the manufacturing difficulty can be lower.

[0030] The second aspect of the present application provides a spectral detection method. The method is implemented based on the dual-rotation-axis angle-scanning tuning spectral sensor, and the method includes:

[0031] Making the light to be detected incident on the sensor;

[0032] Rotating the first carrier and / or the second carrier relative to the incident light to change the incident angle;

[0033] Recording and analyzing the corresponding detection signals output by the sensor when the first carrier and / or the second carrier are at each rotation angle, to achieve spectral detection of the light to be detected.

[0034] Compared with the prior art, the angle-scanning tuning spectral sensor of the present application can effectively expand the angle-scanning range by adopting a dual-rotation-axis design, break through the performance limitations of a single microelectromechanical rotating structure, achieve spectral sampling in a larger wavelength range, and solve defects such as a small working wavelength range existing in tuning spectral detection chips. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The drawings incorporated in this specification and constituting a part of the specification illustrate embodiments of the present application, and together with the specification are further used to explain the present application and enable those skilled in the art to make and use the present application.

[0036] Figure 1It is a top view of an angle-scanning and tuning type spectral sensor based on a parallel dual rotating shaft in the first embodiment of the present application;

[0037] Figure 2 It is a top view of an angle-sensitive structure in the first embodiment of the present application;

[0038] Figure 3 It is a top view of another angle-sensitive structure in the first embodiment of the present application;

[0039] Figure 4 It is a schematic diagram of an integrated structure of an angle-sensitive structure and a detector in the first embodiment of the present application;

[0040] Figure 5 It is a schematic diagram of an integrated structure of another angle-sensitive structure and a detector in the first embodiment of the present application;

[0041] Figure 6 It is a schematic diagram of an integrated structure of yet another angle-sensitive structure and a detector in the first embodiment of the present application;

[0042] Figure 7 It is a dual-axis tuning schematic diagram of an angle-scanning and tuning type spectral sensor in the first embodiment of the present application;

[0043] Figure 8 It is an absorption / transmission spectrum diagram of an angle-sensitive structure in the range of θ1 to θ2 angles in the first embodiment of the present application;

[0044] Figure 9 Is Figure 8 A relationship diagram between the peak wavelength and the incident angle in the shown absorption / transmission spectrum diagram;

[0045] Figure 10 It is an absorption / transmission spectrum diagram of an angle-sensitive structure in the range of θ3 to θ4 angles in the first embodiment of the present application;

[0046] Figure 11 Is Figure 10 A relationship diagram between the peak wavelength and the incident angle in the shown absorption / transmission spectrum diagram;

[0047] Figure 12 It is a top view of an angle-scanning and tuning type spectral sensor based on an orthogonal dual rotating shaft in the second embodiment of the present application;

[0048] Figure 13 It is a top view of an angle-sensitive structure in the second embodiment of the present application;

[0049] Figure 14 It is one of the dual-axis tuning schematic diagrams of an angle-scanning and tuning type spectral sensor in the second embodiment of the present application;

[0050] Figure 15 It is the second of the two-axis tuning schematic diagrams of an angle-scanning tuned spectroscopic sensor in the second embodiment of the present application;

[0051] Figure 16 It is the absorption / transmission spectrogram of an angle-sensitive structure within the angle range of θ1 to θ2 in the second embodiment of the present application;

[0052] Figure 17 It is Figure 16 The relationship diagram between the peak wavelength and the incident angle in the shown absorption / transmission spectrogram;

[0053] Figure 18 It is the absorption / transmission spectrogram of an angle-sensitive structure within the angle range of θ3 to θ4 in the second embodiment of the present application;

[0054] Figure 19 It is Figure 18 The relationship diagram between the peak wavelength and the incident angle in the shown absorption / transmission spectrogram. Detailed implementation manners

[0055] The technical solution, its implementation process, principle, etc. of the present application will be further described below.

[0056] It should be noted that although specific configurations and arrangements are discussed, it should be understood that this is only for illustrative purposes. Therefore, other configurations and arrangements can be used without departing from the scope of the present application. Moreover, the present application can also be adopted in a variety of other applications. The functional and structural features described in the present application can be combined, adjusted, and modified with each other and in various ways not specifically shown in the drawings, such that these combinations, adjustments, and modifications are within the scope of the present application.

[0057] Generally, terms can be understood at least in part according to their usage in context. For example, the term "one or more" used in this specification can, at least in part, depend on the context and can be used to describe any component, structure, or feature in the singular form or can be used to describe a combination of components, structures, or features in the plural form. Similarly, terms such as "a", "an", or "the" can also be understood at least in part according to the context to convey singular usage or convey plural usage. Additionally, the term "based on..." can be understood as not necessarily intended to convey a set of exclusive factors, but can instead, at least in part, depending on the context, allow for the existence of additional factors that do not necessarily have to be explicitly described.

[0058] It should be easily understood that the meanings of "on", "above", and "over" in this application should be interpreted in the broadest sense, such that "on" not only means "directly on something", but also means "on something" including intermediate components or layers between the two, and "above" or "over" not only means the meaning of "above" or "over" something, but also includes the meaning of "above" or "over" something without intermediate components or layers between the two.

[0059] In addition, for ease of description, this specification may use spatial relative terms such as "below", "beneath", "lower", "above", "upper", etc. to describe the relationship between one element or component and another element or component shown in the drawings. In addition to the orientations described in the figures, spatial relative terms are also intended to cover different orientations of the device during use or operation. The device can be oriented in other ways (rotated 90° or in other orientations), and the spatial relative descriptive terms used in this specification can be interpreted accordingly.

[0060] Please refer to Figure 1 As shown, in the first embodiment of this application, an angle-scanning tuned spectroscopic sensor 1 has a parallel dual-rotating shaft structure, which includes a substrate and a spectroscopic detection unit. The substrate includes a first rotatable part 111, a second rotatable part 112, a fixed part 113, a first rotating shaft 114, and a second rotating shaft 115. The spectroscopic detection unit 120 is used to receive the light to be detected as incident light, and includes a detector and an angle-sensitive structure provided on the detector.

[0061] The first rotatable part 111 is rotatably connected to the second rotatable part 112 via the first rotating shaft 114, and the second rotatable part 112 is rotatably connected to the fixed part 113 via the second rotating shaft 115. The first rotating shaft 114 and the second rotating shaft 115 are both disposed on a reference plane and are parallel to each other, and are preferably coaxially disposed. The reference plane is parallel to the surface of the fixed part 113.

[0062] The first rotatable part 111 and the second rotatable part 112 can be respectively named as the first carrier and the second carrier. The spectral detection unit 120 is mounted on the first carrier and can rotate around the first rotation axis relative to the incident light direction together with the first carrier to change the incident angle. The second carrier can drive the spectral detection unit and the first carrier to rotate around the second rotation axis relative to the incident light direction to change the incident angle. The incident light is linearly polarized light, the polarization direction of which is parallel to the aforementioned reference plane and perpendicular to the first rotation axis 114 and the second rotation axis 115. When the spectral detection unit 120 rotates with the first carrier or rotates with the first carrier and the second carrier together, angular scanning relative to the incident light direction can be achieved.

[0063] Since both the first carrier and the second carrier are rotatable, this angular scanning tuned spectral sensor has at least a first state and a second state. In the first state, the surfaces of the first carrier and the second carrier are both parallel to the reference plane. In the second state, the angle formed by the surface of at least one of the first carrier and the second carrier and the reference plane is greater than 0° and less than 90°.

[0064] The first rotatable part 111, the second rotatable part 112, the fixed part 113, the first rotation axis 114 and the second rotation axis 115 can be processed on the same substrate.

[0065] For example, if the substrate is an SOI substrate, the first rotatable part 111, the second rotatable part 112, the fixed part 113, the first rotation axis 114 and the second rotation axis 115 can be processed on the SOI substrate through MEMS processes or the like to form a MEMS silicon micro-mirror structure. Correspondingly, the first rotation axis 114 and the second rotation axis 115 therein are both micro-electromechanical rotation structures.

[0066] The angle-sensitive structure can be a one-dimensional grating structure or a two-dimensional grating structure, but preferably a one-dimensional grating structure, which can be in various forms. For example, it can have Figure 2 or Figure 3 the periodic structure shown. At the same time, the angle-sensitive structure can be integrated with the detector in various forms.

[0067] For example, please refer to Figure 4 , in the first case, the angle-sensitive structure 121 can be integrated on the detector 122. The angle-sensitive structure 121 can be a one-dimensional grating structure formed by metal and / or dielectric materials. The incident light is transmitted through the one-dimensional grating structure and then absorbed by the detector 122. The material of the one-dimensional grating structure can include metals such as gold, platinum, silver, copper, aluminum or titanium, and inorganic non-metallic materials or organic materials such as graphene, titanium nitride, zirconium nitride, indium tin oxide, zinc oxide, silicon dioxide, silicon nitride, aluminum oxide, hafnium oxide, magnesium fluoride or polymethyl methacrylate.

[0068] For another example, please refer to Figure 5 , in the second case, the angle-sensitive structure can also include a part of the detector and can also be a one-dimensional grating structure. The detector is mainly formed of a semiconductor material 122', and a one-dimensional semiconductor grating is formed on its surface by physical / chemical etching or machining. A metal material 121' covers the one-dimensional semiconductor grating, and a metal-semiconductor contact (such as a gold-silicon contact) forms a Schottky detector. At the same time, the one-dimensional grating structure has the characteristic of angle sensitivity, so that only the light energy of the corresponding wavelength can be selectively absorbed by the one-dimensional grating structure at each incident light angle, and then converted into a current output by the Schottky detector. Among them, the thickness of the metal material covering the one-dimensional semiconductor grating is greater than 20 nm and less than or equal to 100 nm, preferably 30-100 nm. In this second case, because narrow-band absorption is required, the thickness of the metal material 121' should be relatively large, preferably >50 nm.

[0069] For yet another example, in the third case, the angle-sensitive structure 121 can also be a one-dimensional grating structure and can be integrally arranged with the detector 122 in the manner shown in Figure 6 . Among them, 1211 is a dielectric material, and its material can be SiO 2 , SiN, etc., and 1212 is a metal material. A one-dimensional dielectric grating is integrally formed on the surface of the dielectric material 1211, and the metal material 1212 covers the one-dimensional dielectric grating. The detector 122 can be an InGaAs detector or the like. After the incident light passes through the first one-dimensional grating structure 31, it is transmitted to the first detector 21. Among them, the thickness of the metal material covering the one-dimensional dielectric grating is greater than 20 nm and less than or equal to 100 nm. In this third case, because narrow-band transmission is required, the thickness of the metal material 1212 should be relatively thin, preferably <40 nm.

[0070] Compared with Figure 4 the one-dimensional grating structure shown in Figure 5 and Figure 6 the one-dimensional grating structure shown in has better performance.

[0071] The detector can be a photodetector or a photothermal detector, etc. In this application, the substrate material (such as an Si substrate) can be directly used as the photoelectric response material of the detector, that is, the substrate material can form a part of the detector. Or, other optoelectronic materials can be introduced on the substrate by methods such as transfer, bonding, and epitaxy, and then a detector (such as graphene, Ge, etc.) is fabricated on the substrate using semiconductor device processes, that is, the substrate mainly serves as a carrier mechanism. Or, a detector that has been independently fabricated (such as an InGaAs, Si, HgTe detector, etc.) can be directly pasted onto the substrate, and the substrate and the detector are completely independent and are connected by wiring, etc.

[0072] The detector may have at least two electrodes, which also form the working electrodes of the spectral detection unit 120. Please continue to refer to Figure 1 , if the detector has a first working electrode 131 and a second working electrode 132, these two working electrodes can be led out to the fixed part 113 along the first rotation axis 114 and the second rotation axis 115 through electrode wiring, and are respectively electrically connected to the first lead-out electrode 141 and the second lead-out electrode 142 provided on the fixed part 113.

[0073] In this embodiment, considering the limited rotation angle of each rotation axis. For example, please refer to Figure 7 , the maximum rotation angle of the first rotatable part 111 around the first rotation axis is θ1, and the maximum rotation angle of the second rotatable part 112 around the second rotation axis is θ2. At a certain moment, the included angle between the first rotatable part 111 and the second rotatable part 112 is θ12, and the included angle between the second rotatable part 112 and the fixed part 113 is θ23. Then 0 ≤ θ23 ≤ θ2, 0 ≤ θ12 ≤ θ1. In some cases, θ1 = θ2. Among them, θ1 and θ2 can be 0 to 25°, further can be 0 to 20°, and still further can be 0 to 15°. In some cases, θ1 and θ2 can be 10 to 15°.

[0074] The polarization direction of the light to be detected 16 as the incident light is parallel to the plane (reference plane) where the fixed part 113 is located and perpendicular to the two rotation axes. Refer to Figures 8 - 11 , when θ23 = 0, that is, only the first rotation axis works alone, the rotation angle range of the first rotatable part 111 is 0 to θ1. Limited by the device design and processing performance, the corresponding incident angle change range is 0 to θ1, and the detection wavelength range is λ1 to λ2. When θ23 ≠ 0, that is, the first rotation axis and the second rotation axis work in a two-axis mode, drive the second rotatable part 112 to rotate θ2 relative to the fixed part 113 and keep it stationary. At the same time, drive the first rotatable part 111 to rotate θ12 relative to the second rotatable part 112 and scan within a certain angle range, and record the output signal of the detector at the same time. Relative to the incident light, the rotation angle range of the first rotatable part 111 is max(0, θ2 - θ1) to θ1 + θ2. This range is larger than the single-axis working case. Therefore, the detection wavelength range is λ1 to λ4, thus breaking through the performance limitations of a single microelectromechanical rotation structure, realizing a large expansion of the angle scanning range, and being able to meet the spectral sampling requirements of a larger wavelength range.

[0075] Please refer to Figure 12As shown, in the second embodiment of the present application, an angle-scanning tunable spectroscopic sensor 2 has an orthogonal double-rotating shaft structure, which also includes a substrate and a spectroscopic detection unit. The substrate includes a first rotatable part 211, a second rotatable part 212, a fixed part 213, a first rotating shaft 214, and a second rotating shaft 215. The spectroscopic detection unit 220 is used to receive the light to be detected as incident light and includes a detector and an angle-sensitive structure disposed on the detector.

[0076] The first rotatable part 211 is rotatably connected to the second rotatable part 212 via the first rotating shaft 214, and the second rotatable part 212 is rotatably connected to the fixed part 213 via the second rotating shaft 215. The first rotating shaft 214 and the second rotating shaft 215 are both disposed on a reference plane and are perpendicular to each other. The reference plane is parallel to the surface of the fixed part 213.

[0077] The first rotatable part 211 and the second rotatable part 212 can be respectively named the first carrier and the second carrier. The spectroscopic detection unit 220 is mounted on the first carrier and can rotate around the first rotating shaft relative to the incident light direction together with the first carrier to change the incident angle. The second carrier can drive the spectroscopic detection unit and the first carrier to rotate around the second rotating shaft relative to the incident light direction together to change the incident angle. The incident light is linearly polarized light, the polarization direction of which is parallel to the aforementioned reference plane and forms a non-zero angle with one of the first rotating shaft 214 and the second rotating shaft 215. For example, it forms an angle of 30-60° with the second rotating shaft 215, and this angle is more preferably about 45°. When the spectroscopic detection unit 220 rotates with the first carrier or rotates with the first carrier and the second carrier together, angle scanning relative to the incident light direction can be achieved. Further, when the second rotatable part 212 does not rotate, the first rotatable part 211 can drive the spectroscopic detection unit to rotate around the first rotating shaft 214. When the first rotatable part 211 does not rotate alone, the second rotatable part 212 can rotate around the second rotating shaft 215 and drive the first rotatable part 211 and the spectroscopic detection unit to rotate together at the same time. Further, in the angle-scanning tunable spectroscopic sensor 2, the rotation movement around the first rotating shaft 214 and the rotation movement around the second rotating shaft 215 are decoupled from each other.

[0078] The angle-scanning tunable spectroscopic sensor 2 also has a first state and a second state. In the first state, the surfaces of the first carrier and the second carrier are both parallel to the reference plane. In the second state, the angle formed by the surface of at least one of the first carrier and the second carrier and the reference plane is greater than 0° and less than 90°, preferably less than or equal to 90°.

[0079] The first rotatable part 211, the second rotatable part 212, the fixed part 213, the first rotation axis 214, and the second rotation axis 215 may also be processed on the same substrate. For example, if the substrate is an SOI substrate, the first rotatable part 211, the second rotatable part 212, the fixed part 213, the first rotation axis 214, and the second rotation axis 215 can be processed on the SOI substrate through MEMS processes or the like to form a MEMS silicon micromirror structure. Correspondingly, the first rotation axis 214 and the second rotation axis 215 therein are both microelectromechanical rotation structures.

[0080] The angle-sensitive structure can be a two-dimensional grating structure, and it can be in various forms. Exemplarily, the two-dimensional grating structure can have Figure 13 the periodic structure shown. Specifically, the two-dimensional grating structure has a first period P1 and a second period P2 in two orthogonal directions respectively. The period direction of the first period P1 is parallel to the first rotation axis 214, and the period direction of the second period P2 is parallel to the second rotation axis 215. Furthermore, different orientations of the gratings in the two-dimensional grating structure correspond to different rotation actions, that is, the rotation action around the first rotation axis 214 and the rotation action around the second rotation axis 215. Interacting with incident light in different angular directions can obtain different resonances, thereby detecting different wavelengths.

[0081] The angle-sensitive structure can also be integrated with the detector in various forms. For example, it can refer to Figures 4 - 6 the form shown for integration on the detector. That is, the angle-sensitive structure can be a two-dimensional grating structure formed by metal and / or dielectric materials. Incident light is transmitted through the one-dimensional grating structure and then absorbed by the detector. Alternatively, the angle-sensitive structure can include a part of the detector. The detector is mainly formed of semiconductor materials, and a two-dimensional semiconductor grating is formed on its surface. The two-dimensional semiconductor grating forms a Schottky contact with the metal material covering its surface, thereby simultaneously forming an angle-sensitive structure and a Schottky detector. Alternatively, the angle-sensitive structure includes a two-dimensional dielectric grating integrally formed on the surface of a dielectric material and a metal material covering the surface of the two-dimensional dielectric grating. The angle-sensitive structure is integrally provided with an InGaAs detector or the like.

[0082] The detector can also be a photodetector or a photothermal detector, etc., and it can be the same as or similar to the detector in the first embodiment of the present application.

[0083] The detector can also have at least two electrodes, and these electrodes also constitute the working electrodes of the spectral detection unit 220. Please continue to refer to Figure 12, if the detector has a first working electrode 231 and a second working electrode 232, the two working electrodes can be led out to the fixed part 213 along the first rotation axis 214 and the second rotation axis 215 through electrode wiring, and are respectively electrically connected to a first lead-out electrode 241 and a second lead-out electrode 242 arranged on the fixed part 213.

[0084] In this embodiment, for the angle-sensitive structure, the two-dimensional grating structure has different dispersion characteristics for different polarized lights, and with different two-dimensional grating periods and different incident angles of the incident light 26, the resonance wavelengths will occur at different positions. Refer to Figures 14 - 19 , if the polarization of the incident light is set to an angle of 45° (or other angles) with the second rotation axis 215, then: 1) when the second rotatable part 212 rotates around the second rotation axis 215 and the first rotatable part 211 does not rotate around the first rotation axis 214, the X polarization component of the incident light is perpendicular to Figure 13 the period direction of the second period P2 as shown, exciting resonance. When the rotation angle θ23 of the second rotatable part 212 (i.e., the angle between the second rotatable part 212 and the fixed part 213) is θ3 to θ4, the resonance wavelength is λ3 to λ4; 2) when the first rotatable part 211 rotates around the first rotation axis 214 and the second rotatable part 212 does not rotate around the second rotation axis 215, the Y polarization component of the incident light is perpendicular to the period direction of the first period P1, exciting resonance. When the rotation angle θ13 of the first rotatable part 211 (i.e., the angle between the first rotatable part 211 and the fixed part 213) is θ1 to θ2, that is, when the incident angle changes from θ1 to θ2, the wavelength of resonance absorption / transmission changes from λ1 to λ2. Among them, λ1 < λ2, λ3 < λ4, λ3 < λ2 < (λ3 + 10 nm). In some cases, θ1 = θ3 = 0, θ2 = θ4. In some cases, θ2, θ4 can be ≤ 25°, further can be ≤ 20°, and even further can be ≤ 15°, for example, can be 10 to 15°. But θ1, θ3, θ2, θ4 can also take other values. Therefore, in this embodiment, by combining these two rotation scanning test methods, the spectral detection wavelength range can cover λ1 to λ4, and it also overcomes the problem of the small working wavelength range caused by the performance limitation of a single microelectromechanical rotation structure in the angle scanning tuning type spectral sensor, realizing spectral sampling in a larger wavelength range.

[0085] It should be understood that the above embodiments are only for illustrating the technical concept and features of the present application, and the purpose is to enable those familiar with this technology to understand the content of the present application and implement it accordingly, and it cannot be used to limit the protection scope of the present application. Any equivalent changes or modifications made according to the spirit and essence of the present application should be covered within the protection scope of the present application.

Claims

1. An angle scanning tunable spectrum sensor based on dual rotating axes, characterized in that: include: A spectrum detection unit is mounted on the first carrier and is used to receive incident light, and the spectrum detection unit includes a detector and an angle sensitive structure arranged on the detector; The first carrier is rotatably connected to the second carrier via a first rotation axis and can rotate around the first rotation axis relative to the direction of the incident light to change the incident angle; The second carrier can drive the spectrum detection unit and the first carrier to rotate around the second rotation axis relative to the direction of the incident light to change the incident angle; Among them, the first rotation axis and the second rotation axis are both arranged on a reference plane, and the angle formed by the first rotation axis and the second rotation axis is 0° or 90°; the polarization direction of the incident light is parallel to the reference plane, and the angles formed with the first rotation axis and the second rotation axis are both greater than 0° and less than 90°.

2. The angle scanning tunable spectrum sensor according to claim 1, characterized in that: The first rotation axis and the second rotation axis are parallel to each other and perpendicular to the polarization direction of the incident light, and the angle sensitive structure includes a one-dimensional grating structure or a two-dimensional grating structure.

3. The angle scanning tunable spectrum sensor according to claim 2, characterized in that: The first rotation axis and the second rotation axis are coaxially arranged; and / or the angle sensitive structure comprises a one-dimensional grating structure.

4. The angle scanning tunable spectrum sensor according to claim 1, characterized in that: The first rotation axis is perpendicular to the second rotation axis, and the angle sensitive structure includes a two-dimensional grating structure.

5. The angle scanning tunable spectrum sensor according to claim 4, characterized in that: The angle between the polarization direction of the incident light and the second rotation axis is 30 to 60°; and / or the two-dimensional grating structure has a first grating period and a second grating period in two orthogonal directions, respectively, wherein the direction of the first grating period is parallel to the first rotation axis, and the direction of the second grating period is parallel to the second rotation axis.

6. The angle scanning tunable spectrum sensor according to claim 1, characterized in that: The detector comprises a photoelectric detector or a photothermoelectric detector; and / or, the detector is integrated with an angle-sensitive structure; and / or, the resonant absorption or transmission spectrum of the angle-sensitive structure changes with the angle of the incident angle.

7. The angle scanning tunable spectrum sensor according to claim 1, characterized in that: It includes a substrate, which includes a fixed part, a first rotatable part, a second rotatable part, a first rotating shaft and a second rotating shaft. The first rotatable part and the second rotatable part are respectively the first carrier and the second carrier. The second rotatable part is rotatably connected to the fixed part through the second rotating shaft.

8. The angle scanning tunable spectrum sensor according to claim 7, characterized in that: The surface of the fixed part is parallel to the reference plane; and / or the angle scanning tunable spectral sensor has at least a first state and a second state, wherein in the first state, the surfaces of the first rotatable part and the second rotatable part are both parallel to the reference plane, and in the second state, the angle between the surface of at least one of the first rotatable part and the second rotatable part and the reference plane is greater than 0° and less than 90°.

9. The angle scanning tunable spectrum sensor according to claim 7, characterized in that: The spectral detection unit has a first working electrode and a second working electrode, the first working electrode and the second working electrode are electrically connected to a first lead-out electrode and a second lead-out electrode via a first electrode wiring and a second electrode wiring, respectively, the first electrode wiring extends from the first rotatable part to the fixed part at least along the first rotation axis, the second electrode wiring extends from the second rotatable part to the fixed part at least along the second rotation axis, and the first lead-out electrode and the second lead-out electrode are respectively arranged on the fixed part.

10. A spectrum detection method, characterized in that: The method is implemented based on the dual-axis angle scanning tunable spectral sensor according to any one of claims 1 to 9, and the method comprises: Allowing the light to be detected to enter the sensor; Rotating the first carrier and / or the second carrier relative to the incident light to change the incident angle; The corresponding detection signal output by the sensor at each rotation angle of the first carrier and / or the second carrier is recorded and analyzed to achieve spectrum detection of the light to be detected.

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