JP2021056129A - Sensor device and method for measuring sensor device - Google Patents

Abstract

To provide a sensor device that can correct an applied voltage of an MEMS Fabry-Perot interferometer.SOLUTION: The sensor device includes: a Fabry-Perot interferometer of which space is changed by applying a voltage on at least one of a first conductive film in contact with a first film and a second conductive film in contact with a second film; an optical sensor for detecting a transmission light of the Fabry-Perot interferometer; and a strain sensor, and corrects the voltage of the Fabry-Perot interferometer on the basis of the strain detected by the strain sensor.SELECTED DRAWING: Figure 1

Description

One embodiment of the present invention relates to a sensor device. In particular, it relates to a sensor device including a Fabry-Perot interferometer using MEMS. The present invention also relates to a method for measuring a sensor device.

The Fabry-Perot interferometer has a gap between the two semi-transmissive mirror thin films to reflect or interfere between the two semi-transmissive mirror thin films. Since the light transmitted through the Fabry-Perot interferometer has a large transmittance at the resonance wavelength, the Fabry-Perot interferometer is used in spectroscopic measurement. Among them, the Fabry-Perot interferometer (MEMS Fabry-Perot interferometer) using the microelectromechanical system (MEMS), which can adjust the distance of the gap by the movable film and change the wavelength of the transmitted light, has a wavelength in a wide band. Suitable for spectroscopic measurement (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2008-134388

However, when the MEMS Fabry-Perot interferometer is bent, the distance between the gaps changes and the movable membrane is deformed. Therefore, there is a problem that the applied voltage of the MEMS Fabry-Perot interferometer at the resonance wavelength differs between the case where the MEMS Fabry-Perot interferometer is not bent and the case where the MEMS Fabry-Perot interferometer is bent.

In view of the above problems, one object of the present invention is to provide a sensor device capable of correcting the applied voltage of the MEMS Fabry-Perot interferometer. Another object of the present invention is to provide a method for measuring a sensor device that corrects an applied voltage of a MEMS Fabry-Perot interferometer.

The sensor device according to an embodiment of the present invention includes a gap between the first film and the second film, and is at least one of a first conductive film in contact with the first film and a second conductive film in contact with the second film. A Fabry-Perot interferometer whose gap changes by applying a voltage to the Fabry-Perot interferometer, an optical sensor that detects the transmitted light of the Fabry-Perot interferometer, and a strain sensor are included, and the fabric is based on the strain detected by the strain sensor. Correct the voltage of the Perot interferometer.

The sensor device according to an embodiment of the present invention includes a gap between the first film and the second film, and is at least one of a first conductive film in contact with the first film and a second conductive film in contact with the second film. Includes a Fabry-Perot interferometer whose gap changes by applying a voltage to the Fabry-Perot interferometer, an optical sensor that detects the transmitted light of the Fabry-Perot interferometer, and a distortion sensor, based on the change in output voltage detected by the strain sensor. And correct the voltage of the Fabry-Perot interferometer.

In the method for measuring a sensor device according to an embodiment of the present invention, in a Fabry-Perot interferometer in which a strain sensor detects strain and includes a gap between the first film and the second film, the first film is in contact with the first film. The gap is changed by applying a voltage associated with the strain to at least one of the conductive film and the second conductive film in contact with the second film, and the optical sensor detects the transmitted light of the Fabry-Perot interferometer.

In the measurement method of the sensor device according to the embodiment of the present invention, the strain sensor detects the amount of change in the output voltage, and the Fabry Perot interferometer including a gap between the first film and the second film has the first film. The gap is changed by applying a voltage associated with the amount of change in the output voltage of the strain sensor to at least one of the first conductive film in contact with the first conductive film and the second conductive film in contact with the second film, and the optical sensor becomes a Fabry Perot. Detects the transmitted light of the interferometer.

It is the schematic which shows the structure of the sensor device which concerns on one Embodiment of this invention. It is the schematic which shows an example of the use of the sensor device which concerns on one Embodiment of this invention. It is the schematic sectional drawing of the MEMS Fabry Perot interferometer of the sensor device which concerns on one Embodiment of this invention. It is a graph which shows the correlation between the wavelength and the light transmission rate when the gap is changed in the MEMS Fabry Perot interferometer of the sensor device which concerns on one Embodiment of this invention. It is the schematic sectional drawing of the collimator of the sensor device which concerns on one Embodiment of this invention. It is a circuit diagram which shows the measuring method of the resistance type strain sensor in the sensor device which concerns on one Embodiment of this invention. It is a schematic diagram of the MEMS Fabry-Perot interferometer of the sensor device which concerns on one Embodiment of this invention. It is an example of the schematic correction table of the sensor device which concerns on one Embodiment of this invention. It is an example of the schematic correction table of the sensor device which concerns on one Embodiment of this invention. It is the schematic which shows the structure of the sensor device which concerns on the modification of one Embodiment of this invention. It is the schematic which shows the structure of the sensor device which concerns on the modification of one Embodiment of this invention. It is the schematic which shows the structure of the sensor device which concerns on the modification of one Embodiment of this invention.

Hereinafter, each embodiment of the present invention will be described with reference to the drawings and the like. However, the present invention can be implemented in various aspects without departing from the gist of the technical idea, and is not construed as being limited to the description contents of the embodiments illustrated below.

In order to clarify the explanation, the drawings may schematically show the width, thickness, shape, etc. of each part as compared with the actual mode, but this is just an example, and the illustrated shape itself is a book. It does not limit the interpretation of the invention. Further, in the drawings, elements having the same functions as those described with respect to the drawings already mentioned in the specification may be designated by the same reference numerals even if they are separate drawings, and duplicate explanations may be omitted. ..

When one film is processed to form a plurality of structures, each structure may have a different function or role, and each structure may have a different base on which it is formed. However, these plurality of structures are derived from films formed as the same layer in the same process and have the same material. Therefore, these multiple films are defined as existing in the same layer.

In expressing the mode of arranging another structure on one structure, when simply expressing "above" or "above", unless otherwise specified, it is in contact with one structure and directly above it. It includes both the case of arranging another structure and the case of arranging another structure above one structure via yet another structure. The same applies to the notation of "below" or "below".

<First Embodiment>
The sensor device 10 according to the embodiment of the present invention will be described with reference to FIGS. 1 to 8.

[1. Sensor device]
FIG. 1 is a schematic view showing a configuration of a sensor device 10 according to an embodiment of the present invention. As shown in FIG. 1, the sensor device 10 includes a light source 11, a Fabry-Perot interferometer 12, a collimator 13, an optical sensor 14, and a strain sensor 15. The light source 11 is provided above the Fabry-Perot interferometer 12. Further, the collimator 13, the optical sensor 14, and the strain sensor 15 are provided below the Fabry-Perot interferometer 12. The collimator 13 is provided between the Fabry-Perot interferometer 12 and the optical sensor 14. The strain sensor 15 is provided below the optical sensor 14. The Fabry-Perot interferometer 12, the collimator 13, the optical sensor 14, and the strain sensor 15 are preferably provided on a flexible substrate so that the sensor device 10 can be bent.

FIG. 2 is a schematic view showing an example of use of the sensor device 10 according to the embodiment of the present invention. The sensor device 10 detects the light emitted from the light source 11 and transmitted through the object 500 by the optical sensor 14. As shown in FIG. 2, the object 500 is installed between the light source 11 and the Fabry-Perot interferometer 12. The light emitted from the light source 11 passes through the object 500 or is reflected by the object 500. Further, light having a predetermined wavelength is absorbed by the object 500. Therefore, the intensity of the light transmitted through the object 500 decreases at a predetermined wavelength. Therefore, the object 500 can be identified from a predetermined wavelength by measuring the intensity of light in a specific wavelength range. The object 500 may be a living body.

The sensor device 10 can also identify the properties of the object 500. For example, if the object 500 is a fruit, the sugar contained in the fruit absorbs light having a predetermined wavelength. Therefore, the sugar content of fruits can be specified by measuring the light intensity in a specific wavelength range and comparing the light intensities of a predetermined wavelength. Further, if the object 500 is a vein, the red blood cells contained in the vein absorb light having a predetermined wavelength, so that the vein pattern can be specified by measuring the intensity of the light having a predetermined wavelength.

The object 500 is not limited to a solid, but may be a liquid or a gas. When the object 500 is a liquid or gas, a mechanism for allowing the liquid or gas to stay may be provided between the light source 11 and the Fabry-Perot interferometer 12, and a mechanism for flowing the liquid or gas may be provided as the light source. It may be provided between 11 and the Fabry-Perot interferometer 12. For example, when the object 500 is a gas, the gas can be specified by flowing the gas between the light source 11 and the Fabry-Perot interferometer 12 and detecting the light having a wavelength absorbed by the gas.

The sensor device 10 can also be divided into a plurality of pixels, and the object 500 can be identified from the detection at each pixel. The arrangement of pixels can be not only a matrix shape but also a honeycomb shape or a houndstooth shape. Further, the sensor device 10 may include an active element such as a transistor in order to control the light source 11, the Fabry-Perot interferometer 12, the optical sensor 14, and the strain sensor 15.

Hereinafter, each configuration of the sensor device 10 will be described in detail.

[2. light source]
The light source 11 can irradiate the object 500 with light. As the light source 11, for example, an incandescent lamp, a halogen lamp, a mercury lamp, a fluorescent lamp, an LED (Light Emitting Diet), an OLED (Organic Light Emitting Diet), or the like can be used. The LED includes a mini LED or a micro LED.

Further, the light source 11 can select the wavelength of light according to the object 500 to be measured. As the wavelength of the light source 11, for example, X-rays, ultraviolet rays, visible rays, near infrared rays, mid infrared rays, or far infrared rays can be used.

The sensor device 10 may be configured not to include the light source 11. That is, the sensor device 10 can also identify the object 500 by using another light source.

[3. Fabry Perot Interferometer]
The Fabry-Perot interferometer 12 can extract light having a resonance wavelength by reflecting or interfering with light between two transflective mirror thin films. As the Fabry-Perot interferometer 12 included in the sensor device 10, a MEMS Fabry-Perot interferometer can be used. In the MEMS Fabry-Perot interferometer, the distance between the gaps can be changed by the applied voltage, so that spectroscopy in a wide band wavelength is possible. Hereinafter, it is assumed that the Fabry-Perot interferometer 12 according to the present embodiment is a MEMS Fabry-Perot interferometer, and the description will be made using the notation of the MEMS Fabry-Perot interferometer 12.

The MEMS Fabry-Perot interferometer 12 will be described with reference to FIG.

FIG. 3 is a schematic cross-sectional view of the MEMS Fabry-Perot interferometer 12 of the sensor device 10 according to the embodiment of the present invention. As shown in FIG. 3, the MEMS Fabry-Perot interferometer 12 includes a first film 100, a second film 110, a first conductive film 120, a second conductive film 130, a first support portion 140, and a second support portion 150. Including. A first conductive film 120 is provided on one surface of the first film 100. A second conductive film 130 is provided on one surface of the second film 110. The first film 100 and the second film 110 are separated by the first support portion 140 and the second support portion 150, and a gap 200 is formed between the first film 100 and the second film 110.

The MEMS Fabry-Perot interferometer 12 moves the second film 110 by using the electrostatic attraction generated between the first conductive film 120 on the first film 100 and the second conductive film 130 on the second film 110. Can be done. That is, a voltage can be applied to at least one of the first conductive film 120 and the second conductive film 130 to move the second film 110. When the first conductive film 120 and the second conductive film 130 have differently signed charges, an attractive force is generated between the first conductive film 120 and the second conductive film 130, and the distance between the gaps 200 becomes smaller. On the other hand, when the first conductive film 120 and the second conductive film 130 have the same electric charge, a repulsive force is generated between the first conductive film 120 and the second conductive film 130, and the distance between the gaps 200 becomes large. .. In the MEMS Fabry-Perot interferometer 12, a specific wavelength (resonant wavelength) can be extracted by changing the distance of the gap 200. That is, the light intensity in a certain wavelength range can be measured by detecting the light intensity with the optical sensor 14 while changing the gap 200 of the MEMS Fabry-Perot interferometer 12.

FIG. 4 is a graph showing the correlation between the wavelength of light and the transmittance when the distance of the gap 200 is changed in the MEMS Fabry-Perot interferometer 12 of the sensor device 10 according to the embodiment of the present invention. In the MEMS Fabry-Perot interferometer 12, the light transmittance is maximized at the resonance wavelength. As the distance of the gap 200 becomes smaller, the resonance wavelength shifts to the shorter wavelength side (arrow 301 in FIG. 4). On the other hand, as the distance of the gap 200 increases, the resonance wavelength shifts to the longer wavelength side (arrow 302 in FIG. 4). When the sensor device 10 is bent, the distance of the gap 200 shown in FIG. 3 changes. Therefore, when the sensor device 10 is bent and the distance of the gap 200 changes, it is necessary to apply a voltage to the MEMS Fabry-Perot interferometer 12 to adjust the distance of the gap 200. Further, when the sensor device 10 is bent, the second film 110 shown in FIG. 3 is also deformed. Also in this case, it is necessary to adjust the applied voltage of the MEMS Fabry-Perot interferometer 12. Specifically, in the MEMS Fabry-Perot interferometer 12, it is necessary to correct the voltage applied to the first conductive film 120 or the second conductive film 130, and this correction method will be described later.

As the material of the first film 100 and the second film 110, inorganic insulating materials such as silicon oxide, silicon nitride, aluminum oxide, aluminum nitride, titanium oxide, titanium nitride, tantalum oxide, and tantalum nitride can be used. The first film 100 and the second film 110 may be a single film of the above-mentioned inorganic insulating material, or may be a laminated film of the above-mentioned inorganic insulating material. Further, as the material of the first film 100 and the second film 110, amorphous silicon, polysilicon, or the like can be used. However, it is preferable that the first film 100 and the second film 110 have translucency in the wavelength range measured by the optical sensor 14. Further, as the material of the first film 100 and the second film 110, an organic resin material such as an acrylic resin, an epoxy resin, a polyimide resin, a silicone resin, a fluororesin, or a siloxane resin can also be used.

The surface of the first film 100 opposite to the gap 200 is preferably fixed to a substrate or another film. Further, it is preferable that the second film 110 has a film thickness that becomes a movable film. The film thickness of the second film 110 is, for example, 1 μm or more and 10 μm or less, preferably 2 μm or more and 4 μm or less. The film thickness of the second film 110 can also be determined in consideration of the resonance wavelength.

As the material of the first conductive film 120 and the second conductive film 130, a transparent conductive oxide such as indium tin oxide (ITO) or zinc oxide indium (IZO) can be used. Further, as the material of the first conductive film 120 and the second conductive film 130, doped amorphous silicon, doped polysilicon, or the like can also be used. However, it is preferable that the first conductive film 120 and the second conductive film 130 have translucency in the wavelength range measured by the optical sensor 14.

The first conductive film 120 and the second conductive film 130 can be provided on the surface of the first film 100 and the second film 110 on the gap 200 side, respectively, but are not limited thereto. The first conductive film 120 and the second conductive film 130 can also be provided on the surface opposite to the gap 200.

The film thickness of each of the first conductive film 120 and the second conductive film 130 is, for example, 20 nm or more and 200 nm or less, preferably 30 nm or more and 60 nm or less. When the thickness of each of the first conductive film 120 and the second conductive film 130 is small, the resistance of the first conductive film 120 and the second conductive film 130 becomes high, and the electric field in the gap 200 becomes non-uniform. Further, when the film thickness of each of the first conductive film 120 and the second conductive film 130 is large, the transmittance of the first conductive film 120 and the second conductive film 130 decreases. Therefore, the film thickness of each of the first conductive film 120 and the second conductive film 130 is preferably in the above range.

The first support portion 140 and the second support portion 150 can be provided at the end of the first film 100 or the second film 110, but are not limited thereto. The first support portion 140 and the second support portion 150 may be provided so as to form a gap 200. Further, the distance of the gap 200 can be adjusted by adjusting the film thickness of the first support portion 140 and the second support portion 150. As the material of the first support portion 140 and the second support portion 150, the same materials as those of the first film 100 and the second film 110 can be used.

The gap 200 can be formed by forming the second film 110 on the sacrificial film and then etching the sacrificial film. The sacrificial film material is a silicon insulating material such as silicon oxide, silicon nitride, or silicon oxynitride, a metal material such as aluminum or copper, or an acrylic resin, epoxy resin, polyimide resin, silicone resin, fluororesin, or siloxane resin. Organic resin materials such as can be used. The sacrificial film is preferably a material having a high etching selectivity with the first film 100, the second film 110, the first support portion 140, and the second support portion 150.

The MEMS Fabry-Perot interferometer 12 can also be formed on a flexible substrate. For example, after forming the MEMS Fabry-Perot interferometer 12 using a silicon substrate, the MEMS Fabry-Perot interferometer 12 is transferred to the flexible substrate. As a result, the MEMS Fabry-Perot interferometer 12 can be bent.

[4. Collimator]
The collimator 13 can make the transmitted light of the object 500 parallel light. When the sensor device 10 is divided into a plurality of pixels, light is detected by an optical sensor 14 provided for each pixel, but light incident from adjacent pixels diagonally on the optical sensor 14 becomes noise. .. Therefore, the collimator 13 is used to adjust the light incident on the optical sensor 14 so as to be the light from the vertical direction.

FIG. 5 is a schematic view of the collimator 13 of the sensor device 10 according to the embodiment of the present invention. The collimator 13 shown in FIG. 5 has a through hole 170 in the black resin layer 160. A MEMS Fabry-Perot interferometer 12 is provided on one side of the through hole 170, and an optical sensor 14 is provided on the other side of the through hole 170. The through hole 170 is provided so as to be perpendicular to the optical sensor 14, and the light passing through the through hole 170 can be incident perpendicular to the optical sensor 14. The amount of light passing through the through hole 170 can be controlled by adjusting the diameter of the through hole 170 and the film thickness of the black resin layer 160. The inside of the through hole 170 can also be filled with a transparent resin.

The collimator 13 is not limited to the pinhole type collimator shown in FIG. The collimator 13 may be, for example, a collimator using a lens, and may be parallel light in which the traveling direction (focus) of the light is adjusted by using the lens.

The sensor device 10 may be configured not to include the collimator 13. However, by providing the collimator 13, it is possible to prevent light that becomes noise from entering the optical sensor 14 as described above. Therefore, it is preferable that the sensor device 10 includes the collimator 13.

[5. Optical sensor]
The optical sensor 14 can detect the light from the light source 11 or the light transmitted through the object 500. The optical sensor 14 is preferably a sensor having a wide wavelength so that the light absorbed by the object 500 can be widely detected. The optical sensor 14 can be, for example, a sensor using a photodiode, a phototransistor, CMOS, or the like.

Further, the optical sensor 14 can select the wavelength to be measured according to the light to be detected. As the wavelength measured by the optical sensor 14, for example, X-rays, ultraviolet rays, visible rays, near infrared rays, or far infrared rays can be used. The wavelength measured by the optical sensor 14 can be adjusted by changing the semiconductor material contained in the optical sensor 14. Examples of the semiconductor material contained in the optical sensor 14 include silicon (amorphous silicon, polysilicon, or single crystal silicon), gallium phosphide, gallium arsenide, phosphorus, indium gallium arsenide, indium antimony, zinc oxide, or Zinc sulfide or the like can be used.

Further, the optical sensor 14 may be a combination of a plurality of optical sensors. For example, the first optical sensor that measures the wavelength region of visible light and the second optical sensor that measures the wavelength region of near infrared rays can be combined to form an optical sensor 14, and the range of wavelengths measured by the optical sensor 14 can be expanded. it can. Further, the optical sensor 14 is formed by combining a third optical sensor that measures the first region of the near infrared ray and a fourth optical sensor that superimposes on the first region and measures the second region of the near infrared ray. It is also possible to improve the accuracy of a part of the infrared rays (the region where the first region and the second region overlap).

The optical sensor 14 is preferably provided on a flexible substrate so that the sensor device 10 can be used in a bent state. As the flexible substrate, for example, an acrylic substrate, a polyimide substrate, a polyethylene terephthalate substrate, a polyethylene naphthalate substrate, or the like can be used.

[6. Strain sensor]
The strain sensor 15 can detect the strain when the sensor device 10 is bent. Specifically, the strain sensor 15 measures the strain of the flexible substrate on which the strain sensor 15 is provided. The strain sensor 15 may be a resistance type strain sensor or a capacitance type strain sensor. The resistance type distortion sensor can detect distortion from the change in the output voltage of the Wheatstone bridge circuit. On the other hand, the capacitance type strain sensor can detect the strain from the change in the capacitance of the elastic body. When the strain sensor 15 is a resistance type strain sensor, it is easy to manufacture, so that the manufacturing cost of the sensor device 10 can be suppressed. On the other hand, when the strain sensor 15 is a capacitance type strain sensor, the strain can be detected even if the strain amount is on the order of nm, so that the strain can be detected with high accuracy.

FIG. 6 is a circuit diagram showing a measurement method of the resistance type strain sensor 15 in the sensor device 10 according to the embodiment of the present invention. Variation ΔR of the resistance value R ₁ due to the distortion of the first resistor 410 is represented by using a strain ε and gauge factor K (Equation 1).

Further, as shown in FIG. 6, the resistance value R ₁ of the first resistor 410 can be measured by using the Wheatstone bridge circuit. Input voltage _{V in} of the Wheatstone bridge circuit output voltage _{V out} for the (third resistor 430 and the input voltage to the fourth resistor 440) (an output voltage from the second resistor 420 and third resistor 430) , (Equation 2).

Here, assuming that R = R ₁ = R ₂ = R ₃ = R ₄ , the amount of change Δe of the output voltage V _out is expressed by (Equation 3).

Further, assuming that ΔR << R in (Equation 3), the _{amount of change Δe of the output voltage V out} is represented by (Equation 4).

Therefore, the strain ε of the first resistor 410 is proportional to the amount of change Δe of the output voltage.

The strain sensor 15 is preferably provided on a flexible substrate so that the sensor device 10 can be used in a bent state. As the flexible substrate, for example, an acrylic substrate, a polyimide substrate, a polyethylene terephthalate substrate, a polyethylene naphthalate substrate, or the like can be used.

The optical sensor 14 and the strain sensor 15 can be provided on one flexible substrate. That is, the strain sensor 15 can be made on the flexible substrate, and the optical sensor 14 can be made on the strain sensor 15.

[7. Fabry-Perot Interferometer Correction with Strain Sensor]
Since the sensor device 10 according to the present embodiment has a flexible substrate as a support substrate, it can be bent. However, when the sensor device 10 is bent, the distance of the gap 200 of the MEMS Fabry-Perot interferometer 12 may change as described above. In addition, the second film 110, which is a movable film, may be deformed. However, in the sensor device 10 according to the present embodiment, the applied voltage of the MEMS Fabry-Perot interferometer 12 can be corrected based on the strain detected by the strain sensor 15. Hereinafter, this correction will be described.

FIG. 7 is a schematic view of the MEMS Fabry-Perot interferometer 12 of the sensor device 10 according to the embodiment of the present invention. FIG. 7 shows the length L (mm) of the second film 110, the film thickness h (mm), the cross-sectional area S (mm ² ), and the distance d (mm) of the gap 200. The electrostatic attraction F (N) or load P (N) of the second film 110 uses the relative permittivity ε ₀ and the displacement amount x, and the applied voltage V (V) of the MEMS Fabry-Perot interferometer 12 to obtain (Equation). It is expressed as 5).

On the other hand, when an evenly distributed load model with both ends fixed is applied to the second film 110, the displacement amount x (mm) of the second film 110 is determined by using the Young's modulus E (N / mm) of the second film 110. It is expressed as (Equation 6).

Here, the moment of inertia of area l when the cross section of the second film 110 is rectangular is expressed as in (Equation 7).

When the sensor device 10 is not bent, the variables in (Equation 4) to (Equation 7) are only the displacement amount x (mm) and the applied voltage V (V). The displacement amount x (mm) of the film 110 can be determined by the applied voltage V (V). In other words, the applied voltage V (V) can control the distance d + x (mm) of the gap 200 and control (spectroscopically) the wavelength of the light passing through the MEMS Fabry-Perot interferometer 12.

However, when the sensor device 10 is bent, the distance d (mm) of the gap 200 changes, and the length L (mm), the film thickness h (mm), and the cross-sectional area S ( Since mm ² ) and the like also change, the relationship between the displacement amount x (mm) of the second film 110 and the applied voltage V (V) does not satisfy (Equation 4) to (Equation 7). Therefore, in the sensor device 10 according to the present embodiment, the applied voltage V (V) is corrected by using the strain detected by the strain sensor 15. Specifically, a correction table is generated in which distortion is used as an input parameter and correction applied voltage V _comp (V) is used as an output parameter. When distortion is detected by the distortion sensor 15, the correction applied voltage V of the correction table is generated. _Comp (V) is applied to drive the MEMS Fabry-Perot interferometer 12. The input parameter may be not only the distortion but also a physical quantity for detecting the distortion. Physical quantities for detecting distortion are, for example, voltage, capacitance, current, or resistance.

The correction table will be described with reference to FIGS. 8A and 8B. Each of FIGS. 8A and 8B is an example of a schematic correction table of the sensor device 10 according to the embodiment of the present invention. The symbol "xxx" in FIGS. 8A and 8B indicates a numerical value. The same symbol "xxx" is described, but the numerical values may be different.

When the resistance type strain sensor shown in FIG. 6 is used as the strain sensor 15, the strain sensor 15 can detect the amount of change Δe of the _{output voltage V out.} In the correction table 450 shown in FIG. 8A, when _{the change amount Δe of the output voltage V out} is input, the correction applied voltage V _{comp of} the MEMS Fabry-Perot interferometer 12 is output. That is, in the correction table 450, the correction applied voltage V _{comp of the} MEMS Fabry-Perot interferometer 12 can be obtained from one input parameter. When the light detected by the optical sensor 14 has a specific wavelength, the Fabry-Perot interferometer 12 is controlled so that the specific wavelength becomes the resonance wavelength. Therefore, at a specific wavelength, _{a correction table 450 in which the change amount Δe of the output voltage V out} and the correction applied voltage V _comp are linked is generated, and when distortion is detected, it is obtained from the correction table 450. The correction applied voltage V _comp is applied to the MEMS Fabry-Perot interferometer 12. Even when the sensor device 10 is bent, the object 500 can be measured by using the correction table 450. When the optical sensor 14 detects light having a plurality of wavelengths, a correction table 450 is generated for each of the plurality of wavelengths.

Further, in the correction table 460 shown in FIG. 8B, when _{the change amount Δe of the output voltage V out} and the resonance wavelength are input, the correction applied voltage V _{comp of} the MEMS Fabry-Perot interferometer 12 is output. That is, in the correction table 460, the correction applied voltage V _{comp of the} MEMS Fabry-Perot interferometer 12 can be obtained from the two input parameters. When spectroscopic measurement is performed by the optical sensor 14, the Fabry-Perot interferometer 12 changes the resonance wavelength within a certain wavelength range. Therefore, a correction table 460 in which the change amount Δe of the output voltage V _out , the resonance wavelength, and the correction applied voltage V _comp are associated with each other is generated. For example, the change amount Δe of the output voltage V _out is fixed, and the resonance wavelength of the MEMS Fabry-Perot interferometer 12 is changed to measure the applied voltage. When this is repeated for each change amount Δe of the output voltage V _out, the correction table 460 shown in FIG. 8B is generated. When distortion is detected, the correction applied voltage V _comp obtained from the correction table 460 is applied to the MEMS Fabry-Perot interferometer 12 while changing the resonance wavelength. Even when the sensor device 10 is bent, the correction table 460 can be used to perform spectroscopic measurement on the object 500.

In the correction table 460 shown in FIG. 8B, the correction applied voltage V _comp of the Fabry-Perot interferometer 12 is associated with the strain (or the _{amount of change Δe of the output voltage V out} of the strain sensor 15) and the resonance wavelength. , The correction table is not limited to this. For example, the correction applied voltage V _comp of the Fabry-Perot interferometer 12 may be associated with the distortion (or the _{amount of change Δe of the output voltage V out} of the distortion sensor 15) and the distance between the gaps.

Further, the correction table measures the resonance wavelength when the sensor device 10 is not bent, the resonance wavelength when the sensor device 10 is bent, and the amount of change Δe (V) of _{the output voltage V out of the distortion sensor 15.} The voltage obtained by adjusting the difference in resonance wavelength can also be set _{as the correction applied voltage V comp (V).} Also in this case, the correction applied voltage V _comp of the Fabry-Perot interferometer 12 generates a correction table associated with the distortion (or the _{amount of change Δe of the output voltage V out} of the distortion sensor 15) and the difference in resonance wavelength. Can be done.

Further, when the sensor device 10 includes a plurality of pixels and a MEMS Fabry-Perot interferometer 12 is provided for each pixel, a correction table can be generated for each MEMS Fabry-Perot interferometer 12 for each pixel.

The sensor device 10 may include a processing unit and a storage unit. The correction table may be stored in the storage unit, and the processing unit may refer to the correction table to determine the applied voltage.

The correction table can be generated, for example, before the sensor device 10 is sold, that is, in the inspection process before shipping, but the present invention is not limited to this. For example, after the sensor device 10 is sold, a correction table according to the usage pattern of the sensor device 10 can be created and written in the storage unit of the sensor device 10.

In the measurement with the sensor device 10, the strain sensor 15 detects the strain (or the _{amount of change Δe of the output voltage V out of the strain sensor 15), and the correction applied voltage V comp} of the Fabry-Perot interferometer 12 is calculated based on the correction table. By determining, spectroscopic measurements on the object 500 can be performed.

As described above, according to the sensor device 10 according to the present embodiment, when the sensor device 10 is bent, the strain sensor 15 detects the strain, and the correction table is used to correct the applied voltage of the MEMS Fabry-Perot interferometer 12. Therefore, the sensor device 10 can be used even in a bent state. Therefore, the sensor device 10 can perform highly accurate measurement in various environments.

The present embodiment can be modified or modified in various ways. Hereinafter, some modifications of the present embodiment will be described. However, the modification of this embodiment is not limited to the following. In the following modification, the description of the same configuration as that of the sensor device 10 will be omitted.

<Modification example 1>
FIG. 9 is a schematic view showing the configuration of the sensor device 10A according to the modified example of the embodiment of the present invention. As shown in FIG. 9, the sensor device 10A includes a light source 11, a collimator 13A, a Fabry-Perot interferometer 12, an optical sensor 14, and a strain sensor 15. The light source 11 is provided above the collimator 13A. Further, the Fabry-Perot interferometer 12, the optical sensor 14, and the strain sensor 15 are provided below the collimator 13A. That is, the collimator 13A is provided above the Fabry-Perot interferometer 12.

In the sensor device 10A, since the collimator 13A is provided on the Fabry-Perot interferometer 12, the light incident on the Fabry-Perot interferometer 12 can be made parallel light. Therefore, since the adjusted light is separated by the Fabry-Perot interferometer 12, the sensor device 10A can perform highly accurate measurement.

<Modification 2>
FIG. 10 is a schematic view showing the configuration of the sensor device 10B according to the modified example of the embodiment of the present invention. As shown in FIG. 10, the sensor device 10B includes a light source 11, a strain sensor 15B, a Fabry-Perot interferometer 12, a collimator 13, and an optical sensor 14. The light source 11 is provided above the strain sensor 15B. Further, the Fabry-Perot interferometer 12, the collimator 13, and the optical sensor 14 are provided below the strain sensor 15B. That is, the strain sensor 15B is provided above the Fabry-Perot interferometer 12. Since the strain sensor 15B needs to transmit light, it is preferable that the strain sensor 15B has translucency.

In the sensor device 10B, since the strain sensor 15B is provided on the Fabry-Perot interferometer 12, the strain of the strain sensor 15B is close to the strain of the movable film of the Fabry-Perot interferometer 12. Therefore, since the correction of the movable film becomes accurate, the sensor device 10B can perform highly accurate measurement.

<Modification example 3>
FIG. 11 is a schematic view showing the configuration of the sensor device 10C according to the modified example of the embodiment of the present invention. As shown in FIG. 11, the sensor device 10C includes a collimator 13C, a Fabry-Perot interferometer 12, an optical sensor 14, a strain sensor 15, and a light source 11C. A collimator 13C is provided above the Fabry-Perot interferometer 12, and an optical sensor 14 and a strain sensor 15 are provided below the Fabry-Perot interferometer 12. The light source 11C is provided below the strain sensor 15.

In the sensor device 10C, the object 500 is installed on the collimator 13C. The light emitted from the light source 11C passes through the strain sensor 15, the optical sensor 14, the Fabry-Perot interferometer 12, and the collimator 13C, and is reflected by the object 500. The reflected light from the object 500 passes through the collimator 13C and the Fabry-Perot interferometer 12 and is detected by the optical sensor 14. The strain sensor 15, the optical sensor 14, the Fabry-Perot interferometer 12, and the collimator 13C may be provided with a portion through which the light emitted from the light source 11C passes.

As the light source 11C of the sensor device 10C, a light source of a mobile information terminal such as a smartphone or a tablet can be used. That is, the sensor device 10C can be provided on the screen of the mobile information terminal. By providing the sensor device 10C on the screen of the mobile information terminal, the sensor device 10C can be used as fingerprint authentication or vein authentication. Since the sensor device 10C can be bent, it can be provided not only on the screen of the mobile information terminal but also on the side surface of the mobile information terminal. Further, the sensor device 10C can also be provided as a part of the portable information terminal.

As described above, also in the sensor devices 10A, 10B, and 10C according to the modified example of the present embodiment, when the sensor devices 10A, 10B, and 10C are bent, the strain sensor 15 or the strain sensor 15B detects the strain and the correction table. Is used to correct the applied voltage of the MEMS Fabry-Perot Interferometer 12. Therefore, the sensor devices 10A, 10B, and 10C can be used even in a bent state. Therefore, the sensor devices 10A, 10B, and 10C can perform highly accurate measurements in various environments.

All sensor devices that can be appropriately designed and implemented by those skilled in the art based on the sensor devices 10, 10A, 10B, and 10C described above as embodiments of the present invention are also included in the present invention as long as the gist of the present invention is included. It belongs to the scope of the invention.

In the scope of the idea of the present invention, those skilled in the art can correspond to various modified examples and modified examples, and it is understood that these modified examples and modified examples also belong to the scope of the present invention. For example, those skilled in the art appropriately adding, deleting, or changing the design of each of the above-described embodiments, or adding, omitting, or changing the conditions of the process are also gist of the present invention. Is included in the scope of the present invention as long as the above is provided.

In addition, other actions and effects brought about by the embodiments in the present embodiment are clearly understood from the description of the present specification, or those which can be appropriately conceived by those skilled in the art are naturally understood to be brought about by the present invention.

10, 10A, 10B, 10C: Sensor device, 11, 11C: Light source, 12: Fabry-Perot interferometer (MEMS Fabry-Perot interferometer), 13, 13A, 13C: Collimator, 14: Optical sensor, 15, 15B: Distortion Sensor, 100: 1st film, 110: 2nd film, 120: 1st conductive film, 130: 2nd conductive film, 140: 1st support part, 150: 2nd support part, 160: black resin layer, 170: Through hole, 200: Gap, 301, 302: Arrow, 410: First resistor, 420: Second resistor, 430: Third resistor, 440: Fourth resistor, 450A, 450B: Correction table, 500: Object

Claims (14)

A gap is included between the first film and the second film, and the distance between the gaps is provided by applying a voltage to at least one of the first conductive film in contact with the first film and the second conductive film in contact with the second film. With a Fabry-Perot interferometer that changes
An optical sensor that detects the transmitted light of the Fabry-Perot interferometer,
Including strain sensor,
A sensor device that corrects the voltage of the Fabry-Perot interferometer based on the strain detected by the strain sensor. A gap is included between the first film and the second film, and the distance between the gaps is provided by applying a voltage to at least one of the first conductive film in contact with the first film and the second conductive film in contact with the second film. With a Fabry-Perot interferometer that changes
An optical sensor that detects the transmitted light of the Fabry-Perot interferometer,
Including strain sensor,
A sensor device that corrects the voltage of the Fabry-Perot interferometer based on the amount of change in the output voltage detected by the strain sensor. The sensor device according to claim 1 or 2, wherein the optical sensor is located between the Fabry-Perot interferometer and the strain sensor. The sensor device according to claim 1 or 2, wherein the Fabry-Perot interferometer is located between the strain sensor and the optical sensor. In addition, including a collimator,
The sensor device according to claim 1 or 2, wherein the collimator is located between the Fabry-Perot interferometer and the optical sensor. In addition, including a collimator,
The sensor device according to claim 1 or 2, wherein the Fabry-Perot interferometer is located between the collimator and the optical sensor. The sensor device according to any one of claims 1 to 6, wherein the correction is performed using the correction table. The sensor device according to claim 7, wherein the correction table determines the voltage from one input parameter. The sensor device according to claim 7, wherein the correction table determines the voltage from two input parameters. further,
The storage unit where the correction table is stored and
The sensor device according to any one of claims 1 to 6, comprising a processing unit that determines the voltage with reference to the correction table. The sensor device according to any one of claims 1 to 10, wherein the Fabry-Perot interferometer, the optical sensor, and the strain sensor are provided on a flexible substrate. The strain sensor detects the strain and
In a Fabry-Perot interferometer containing a gap between the first film and the second film, the strain is associated with at least one of the first conductive film in contact with the first film and the second conductive film in contact with the second film. By applying the applied voltage, the distance between the gaps is changed.
A method for measuring a sensor device in which an optical sensor detects the transmitted light of the Fabry-Perot interferometer. The strain sensor detects the amount of change in the output voltage and
In a Fabry-Perot interferometer containing a gap between the first film and the second film, the strain sensor is used on at least one of the first conductive film in contact with the first film and the second conductive film in contact with the second film. By applying a voltage associated with the amount of change in the output voltage, the distance between the gaps is changed.
A method for measuring a sensor device in which an optical sensor detects the transmitted light of the Fabry-Perot interferometer. The method for measuring a sensor device according to claim 12 or 13, wherein the associated voltage is obtained by referring to a correction table.

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