JP2016001323A - Wavelength variable interference filter, optical module and electronic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wavelength variable interference filter capable of accurately extracting light with a desired wavelength, and further to provide an optical module and an electronic apparatus.SOLUTION: A wavelength variable interference filter 5 comprises: a fixed substrate 51; a movable substrate 52; a fixed reflecting film 54 disposed on a surface opposite to the movable substrate 52 of the fixed substrate 51; a movable reflecting film 55 that is disposed on a surface opposite to the fixed substrate 51 of the movable substrate 52 and is opposite to the fixed reflecting film 54 through a gap G1 between the fixed reflecting film 54 and the movable reflecting film 55; and a fixed electrode 561 disposed on the surface opposite to the movable substrate 52 of the fixed substrate 51. The fixed substrate 51 includes: a reflecting film fixing surface 512A on which the fixed reflecting film 54 is disposed; and a fixed electrode surface 511A on which the fixed electrode 561 is disposed having a distance from the movable substrate 52 different from that of the reflecting film fixing surface 512A. A laminated portion 57 laminated with the fixed reflecting film 54 and the fixed electrode 561 is disposed on the fixed electrode surface 511A having the distance from the movable substrate 52 greater than that of the reflecting film fixed surface 512A.

Description

  The present invention relates to a wavelength tunable interference filter, an optical module including the wavelength tunable interference filter, and an electronic apparatus including the optical module.

  2. Description of the Related Art Conventionally, there has been known a wavelength variable interference filter in which reflection films are arranged on opposite surfaces of a pair of substrates with a predetermined gap therebetween (see, for example, Patent Document 1).

  In the wavelength tunable interference filter described in Patent Document 1, a reflective layer is provided on the opposing surfaces of the two optical substrates, and a capacitive electrode is provided on the opposing surfaces of these optical substrates, on the outer diameter side of the reflective layer. ing. In this wavelength tunable interference filter, the capacitive electrodes facing each other act as an electrostatic actuator, and by applying a voltage between these capacitive electrodes, the gap between the reflective layers is changed by electrostatic attraction.

JP 2002-277758 A

  By the way, in such a tunable interference filter, electric charges may accumulate on the reflective layer, and an electrostatic force is generated when the opposing reflective layers are charged. For this reason, even when a predetermined set voltage is applied to the electrostatic actuator to set the gap between the reflective layers to a set value, the gap may not be set to a desired set value due to electrostatic force due to charging of the reflective layer. . In this case, there is a problem that it becomes difficult to extract light having a desired wavelength from the wavelength variable interference filter.

  An object of the present invention is to provide a wavelength tunable interference filter, an optical module, and an electronic device that can accurately extract light having a desired wavelength.

  The wavelength tunable interference filter of the present invention includes a first substrate, a second substrate facing the first substrate, a first reflecting film provided on a surface of the first substrate facing the second substrate, A second reflective film provided on a surface of the second substrate facing the first substrate, facing the first reflective film via a gap between the reflective films, and a surface facing the second substrate of the first substrate; The first substrate is provided with a first reflective film fixing surface on which the first reflective film is provided, the first electrode is provided, and the distance from the second substrate is A first electrode surface different from the first reflection film fixing surface, and the first reflection film fixing surface and the first electrode surface, the surface having a large distance from the second substrate, A laminated portion in which one reflective film and the first electrode are laminated is provided.

According to the present invention, the first reflection film and the first electrode are formed by laminating the first reflection film fixing surface and the first electrode surface of the first substrate on a surface having a large distance from the second substrate. A laminated part is provided, and the first reflective film and the first electrode are brought into surface contact and electrically conducted by the laminated part. Thereby, even when the first reflective film is charged, the staying charge can be released from the first electrode, and the generation of electrostatic force due to charging between the first reflective film and the second reflective film can be prevented.
Here, it is also conceivable that the end edge of the first electrode and the end edge of the first reflective film are brought into contact with each other for electrical conduction. However, in this case, since the contact area is small and the conduction reliability is low, there is a possibility that the charge of the first reflective film cannot be surely released to the first electrode. In contrast, as described above, by laminating the first electrode and the first reflective film and providing the laminated portion, the first electrode and the first reflective film are surely brought into surface contact and electrically conducted. be able to.
Furthermore, in the present invention, the laminated portion is provided on one surface having a large distance from the second substrate among the first reflecting film fixing surface and the first electrode surface. For this reason, the amount of change in the gap between the reflective films and the gap between the electrodes is not suppressed by the stacked portion. Therefore, it is possible to prevent the disadvantage that the wavelength range that can be extracted by the wavelength tunable interference filter is narrowed.

In the wavelength tunable interference filter of the present invention, the second substrate is provided on a surface of the second substrate facing the first substrate, and is opposed to the first electrode through an interelectrode gap larger than the gap between the reflective films. The electrode includes an electrode, and the laminated portion is configured by laminating the first reflective film extending from the first reflective film fixing surface to the first electrode surface and an outer peripheral edge of the first electrode. It is preferable.
In the wavelength tunable interference filter, the wavelength extracted by transmitting or reflecting is determined by the gap between the reflecting films between the first reflecting film and the second reflecting film. Therefore, in order to acquire the transmission or reflection wavelength corresponding to a wider wavelength range in the wavelength tunable interference filter, it is necessary to increase the fluctuation range of the gap between the reflection films. Here, when a voltage is applied between the first electrode and the second electrode and the gap between the reflective films is changed by electrostatic attraction, if the gap between the electrodes is smaller than the gap between the reflective films, the gap between the electrodes is The gap between the reflective films can be changed only between the two. In such a configuration, the fluctuation range of the gap between the reflection films is reduced, and the wavelength range that can be extracted by the wavelength variable interference filter is reduced.
On the other hand, in the present invention, the gap between the electrodes is formed larger than the gap between the reflective films, so that the gap between the reflective films can be changed in a larger fluctuation range and can be taken out by the variable wavelength interference filter. The possible wavelength range can be broadened.
In general, the electrostatic attractive force acting between the electrodes is inversely proportional to the square of the distance. Therefore, if the gap between the electrodes becomes small, it becomes difficult to control the electrostatic attractive force, and it is difficult to adjust the gap between the reflective films. On the other hand, in the present invention, the gap between the electrodes is formed larger than the gap between the reflective films, so that the electrostatic attractive force can be easily controlled, and the gap between the reflective films can be accurately set to a desired value. it can.

In the wavelength tunable interference filter according to the aspect of the invention, it is preferable that the stacked unit is configured by stacking the first reflective film on the first electrode.
In the present invention, the laminated portion has a configuration in which the first reflective film is laminated on the first electrode. That is, after the first electrode is formed on the first substrate, the first reflective film is formed. Here, if the first reflective film is formed on the first substrate before forming the first electrode, the first reflective film is likely to be deteriorated when the first electrode is formed, and the resolution of the wavelength variable interference filter is lowered. Problems occur. On the other hand, after forming a 1st electrode in a 1st board | substrate previously, degradation of the 1st reflective film in a manufacturing process can be suppressed by forming a 1st reflective film. Therefore, it is possible to form the first reflective film having good reflection characteristics, and it is possible to suppress a decrease in resolution in the wavelength variable interference filter.

In the variable wavelength interference filter according to the aspect of the invention, it is preferable to include a reflective film connection electrode connected to the second reflective film.
In this invention, since the reflective film connection electrode is connected to the second reflective film, the electric charge staying in the second reflective film can be released from the reflective film connection electrode, and the first reflective film and the second reflective film The generation of electrostatic force between them can be prevented more reliably. Therefore, the gap between the reflective films can be controlled with high accuracy by controlling the voltage applied to the first electrode and the second electrode.
Further, the reflective film connection electrode and the first electrode can be set to the same potential, and even in this case, an electrostatic attractive force is not generated between the first reflective film and the second reflective film. The gap can be controlled easily and with high accuracy.

The optical module according to the present invention includes the above-described variable wavelength interference filter and a detection unit that detects light extracted by the variable wavelength interference filter.
As described above, the wavelength tunable interference filter of the present invention can release the electric charge from the first electrode even when the first reflective film is charged. In addition, the size of the gap between the reflective films can be controlled. As a result, the variable wavelength interference filter can extract light having a desired wavelength that is transmitted or reflected with high accuracy. In an optical module equipped with such a tunable interference filter, the amount of light of the desired wavelength extracted by the tunable interference filter is detected by the detection unit, so that the amount of light of the desired wavelength is accurately detected. can do.

In the optical module of the present invention, the variable wavelength interference filter includes a reflective film connection electrode connected to the second reflective film, and the optical module has the same potential for the reflective film connection electrode and the first electrode. It is preferable to provide a voltage control unit.
In the present invention, the voltage control unit sets the reflection film connection electrode connected to the second reflection film and the first electrode to the same potential. As a result, the potential difference between the first reflective film and the second reflective film becomes zero, so that no electrostatic attractive force is generated between the first reflective film and the second reflective film, and the size of the gap between the reflective films is accurately determined. Can be controlled.

An electronic apparatus according to the present invention includes the above-described optical module.
According to the present invention, since the electronic device includes the optical module having the wavelength variable interference filter described above, various electronic processes in the electronic device are performed based on the light amount of the light having the desired wavelength detected with high accuracy. Can do.

1 is a block diagram showing a schematic configuration of a color measurement device according to an embodiment of the present invention. The top view of the wavelength variable interference filter of this embodiment. Sectional drawing of the wavelength variable interference filter of this embodiment. Sectional drawing which shows schematic structure of the wavelength variable interference filter of other embodiment. Sectional drawing which shows schematic structure of the wavelength variable interference filter of other embodiment. Schematic of the gas detection apparatus which is the other example of the electronic device of this invention. The block diagram of the gas detection apparatus of FIG. The block diagram which shows the structure of the food analyzer which is another example of the electronic device of this invention. Schematic of the spectroscopic camera which is the other example of the electronic device of this invention.

Hereinafter, an embodiment according to the present invention will be described with reference to the drawings.
[1. (Schematic configuration of the color measuring device)
FIG. 1 is a block diagram illustrating a schematic configuration of a color measurement device 1 (electronic device) according to the present embodiment.
As shown in FIG. 1, the color measurement device 1 includes a light source device 2 that emits light to the inspection target A, a color measurement sensor 3 (optical module), and a control device 4 that controls the overall operation of the color measurement device 1. Is provided. The colorimetric device 1 reflects the light emitted from the light source device 2 by the inspection object A, receives the reflected inspection light by the colorimetric sensor 3, and outputs the light from the colorimetric sensor 3. This is an apparatus that analyzes and measures the chromaticity of the inspection target light, that is, the color of the inspection target A, based on the detection signal.

[2. Configuration of light source device]
The light source device 2 includes a light source 21 and a plurality of lenses 22 (only one is shown in FIG. 1), and emits white light to the inspection target A. The plurality of lenses 22 may include a collimator lens. In this case, the light source device 2 converts the white light emitted from the light source 21 into parallel light by the collimator lens and inspects from a projection lens (not shown). Inject toward the subject A. In the present embodiment, the colorimetric device 1 including the light source device 2 is illustrated. However, for example, when the inspection target A is a light emitting member such as a liquid crystal panel, the light source device 2 may not be provided.

[3. (Configuration of colorimetric sensor)
As shown in FIG. 1, the colorimetric sensor 3 has a variable wavelength interference filter 5, a detection unit 31 that receives light transmitted through the variable wavelength interference filter 5, and a variable wavelength of light transmitted through the variable wavelength interference filter 5. Voltage control unit 32. Further, the colorimetric sensor 3 includes an incident optical lens (not shown) that guides the reflected light (inspection light) reflected by the inspection object A at a position facing the variable wavelength interference filter 5. In the colorimetric sensor 3, the wavelength variable interference filter 5 separates the light having a predetermined wavelength from the inspection target light incident from the incident optical lens, and the detected light is received by the detection unit 31.
The detection unit 31 includes a plurality of photoelectric exchange elements, and generates an electrical signal corresponding to the amount of received light. And the detection part 31 is connected to the control apparatus 4, and outputs the produced | generated electric signal to the control apparatus 4 as a light reception signal.

(3-1. Configuration of wavelength tunable interference filter)
FIG. 2 is a plan view showing a schematic configuration of the variable wavelength interference filter 5, and FIG. 3 is a cross-sectional view showing a schematic configuration of the variable wavelength interference filter 5.
As shown in FIG. 2, the wavelength variable interference filter 5 is a planar square plate-like optical member. As shown in FIG. 3, the variable wavelength interference filter 5 includes a fixed substrate 51 that is a first substrate of the present invention and a movable substrate 52 that is a second substrate of the present invention. The fixed substrate 51 and the movable substrate 52 are each formed of, for example, various types of glass such as soda glass, crystalline glass, quartz glass, lead glass, potassium glass, borosilicate glass, and non-alkali glass, or crystal. . And these fixed board | substrate 51 and movable board | substrate 52 have the 1st joining surface 513 formed in the outer peripheral part vicinity, the 2nd joining surface 523 is the joining film comprised by the plasma polymerization film etc. which have siloxane as a main component, etc., for example. By being joined by 53, it is comprised integrally.

The fixed substrate 51 is provided with a fixed reflective film 54 constituting the first reflective film of the present invention, and the movable substrate 52 is provided with a movable reflective film 55 constituting the second reflective film of the present invention. Here, the fixed reflective film 54 is fixed to the surface of the fixed substrate 51 facing the movable substrate 52, and the movable reflective film 55 is fixed to the surface of the movable substrate 52 facing the fixed substrate 51. Further, the fixed reflection film 54 and the movable reflection film 55 are disposed to face each other via the inter-reflection film gap G1.
Furthermore, the wavelength variable interference filter 5 is provided with an electrostatic actuator 56 that is used to adjust the dimension of the inter-reflective film gap G1 between the fixed reflective film 54 and the movable reflective film 55. The electrostatic actuator 56 includes a fixed electrode 561 as a first electrode of the present invention provided on the fixed substrate 51 side and a movable electrode 562 as a second electrode of the present invention provided on the movable substrate 52 side. . Here, the fixed electrode 561 and the movable electrode 562 may be provided directly on the substrate surfaces of the fixed substrate 51 and the movable substrate 562, respectively, or may be provided via other film members.
Further, when the wavelength variable interference filter 5 is viewed from the thickness direction of the fixed substrate 51 (movable substrate 52) in a plan view as shown in FIG. 2 (hereinafter referred to as filter plan view), the fixed substrate 51 and the movable substrate 52 The plane center point O coincides with the center point of the fixed reflection film 54 and the movable reflection film 55 and coincides with the center point of the movable portion 521 described later.

(3-1-1. Configuration of Fixed Substrate)
The fixed substrate 51 is formed by processing a glass base material having a thickness of, for example, 500 μm. Specifically, as shown in FIG. 3, the fixed substrate 51 is formed with an electrode formation groove 511 and a reflective film fixing portion 512 by etching. The fixed substrate 51 is formed to have a thickness larger than that of the movable substrate 52, and the fixed substrate is caused by electrostatic attraction when a voltage is applied between the fixed electrode 561 and the movable electrode 562 or internal stress of the fixed electrode 561. There is no 51 deflection.

The electrode forming groove 511 is formed in an annular shape centered on the plane center point O of the fixed substrate 51 in the filter plan view. The reflection film fixing portion 512 is formed so as to protrude from the central portion of the electrode forming groove 511 toward the movable substrate 52 in the plan view. Here, the groove bottom surface of the electrode forming groove 511 is the fixed electrode surface 511A which is the first electrode surface of the present invention, and the protruding front end surface of the reflective film fixing portion 512 is the reflective film fixing surface 512A of the present invention.
In addition, the fixed substrate 51 is provided with three electrode lead-out grooves (not shown) extending from the electrode forming grooves 511 toward the apexes C1, C2, and C3 of the outer peripheral edge of the fixed substrate 51.

On the fixed facing surface 51A of the fixed substrate 51, an annular fixed electrode 561 centering on the plane center point O is formed. Here, the annular shape of the fixed electrode 561 is preferably formed in an annular shape. Further, as the annular shape, a configuration in which the fixed extraction electrode 563 protrudes from a part of the annular shape, a configuration in which a part of the annular ring is missing, or a substantially C in which a part of the annular ring is divided. The structure which becomes character shape is also included.
Note that an insulating film for preventing discharge between the fixed electrode 561 and the movable electrode 562 may be stacked on the fixed electrode 561.
In addition, a fixed extraction electrode 563 extending from the outer peripheral edge of the fixed electrode 561 is formed on the fixed substrate 51. Specifically, the fixed extraction electrode 563 is formed from the position closest to the vertex C1 on the outer peripheral edge of the fixed electrode 561 to the vertex C1 along the electrode formation groove extending in the direction toward the vertex C1. ing. And the front-end | tip part (part located in the vertex C1 of the fixed board | substrate 51) of the fixed extraction electrode 563 comprises the fixed electrode pad 563P.

  The fixed substrate 51 is provided with a first counter electrode 581 and a second counter electrode 582 in electrode lead grooves formed in a direction from the electrode forming groove 511 toward the apexes C2 and C3 of the fixed substrate 51, respectively. Yes. The first counter electrode 581 and the second counter electrode 582 are insulated from the fixed electrode 561. Further, the tip portions of the first counter electrode 581 and the second counter electrode 582 (portions located at the vertices C2 and C3 of the fixed substrate 51) are respectively connected to the first counter electrode pad 581P and the second counter electrode pad 582P. Configure.

As described above, the reflective film fixing portion 512 is formed in a substantially cylindrical shape that is coaxial with the electrode forming groove 511 and has a smaller diameter than the electrode forming groove 511, and is formed on the movable substrate 52 of the reflective film fixing portion 512. The opposing surface (protruding tip surface) is the reflective film fixing surface 512A of the present invention.
Here, the reflection film fixing portion 512 is formed so as to protrude from the electrode forming groove 511 toward the movable substrate 52 as described above. Therefore, the reflective film fixed surface 512A is located closer to the movable substrate 52 than the fixed electrode surface 511A. That is, in the present embodiment, the dimension of the interelectrode gap G2 is formed larger than the dimension of the inter-reflection film gap G1.

Further, since the electrode forming groove 511 and the reflective film fixing portion 512 are formed by etching (wet etching) one surface side of the fixed substrate 51, the outer peripheral side surface 512B of the reflective film fixing portion 512 is the substrate of the fixed substrate 51. It is not a surface parallel to the thickness direction, but has a curved shape that gently curves from the reflective film fixed surface 512A toward the fixed electrode surface 511A.
The fixed reflective film 54 is provided so as to cover the reflective film fixed surface 512A, the outer peripheral side surface 512B, and the inner peripheral portion of the ring-shaped fixed electrode 561 provided on the fixed electrode surface 511A. Here, a laminated portion 57 is configured by a portion where the fixed reflective film 54 and the fixed electrode 561 are laminated. As shown in FIG. 2, the fixed reflective film 54 is formed in a circular shape centered on the plane center point O in the filter plan view. Therefore, the laminated portion 57 also has a ring shape along a virtual circle centered on the plane center point O.
As the fixed reflection film 54, a conductor can be used. As the conductor film, for example, a single layer film of Ag or Ag alloy can be used. In the case of the dielectric multilayer film, for example, a dielectric multilayer film in which the high refractive layer is TiO ₂ and the low refractive layer is SiO ₂ can be used.
Such a fixed reflective film 54 is in surface contact with the fixed electrode 561 by the laminated portion 57 and is electrically connected to the fixed electrode 561. Thereby, even when the fixed reflective film 54 is charged, the staying charge can be released to the fixed electrode 561. Further, when the dielectric film which is an insulator and a multilayer film thereof are laminated on the metal film as the fixed reflection film 54, the metal film and the fixed film are fixed at least in the surface contact portion with the fixed electrode 561 in the laminated portion 57. The electrode 561 is brought into direct contact with and electrically connected. As a result, even when the fixed reflective film 54 is charged, it is possible to release the charges staying in the vicinity of the metal film and the interface between the metal film and the insulating film to the fixed electrode 561.

  Further, an antireflection film (not shown) is formed on the fixed substrate 51 at a position corresponding to the fixed reflection film 54 on the surface opposite to the movable substrate 52. This antireflection film is formed by alternately laminating a low refractive index film and a high refractive index film, and reduces the reflectance of visible light on the surface of the fixed substrate 51 and increases the transmittance.

(3-1-2. Configuration of movable substrate)
The movable substrate 52 is formed by processing a glass substrate having a thickness of, for example, 200 μm by etching.
Specifically, the movable substrate 52 has a circular movable portion 521 centered on the plane center point O in the filter plan view as shown in FIG. 2 and a holding that holds the movable portion 521 and is coaxial with the movable portion 521. Part 522.
Further, as shown in FIG. 2, the movable substrate 52 is provided with notches 524 corresponding to the vertices C1, C2, and C3 of the fixed substrate 51, so that the wavelength variable interference filter 5 is connected to the movable substrate 52 side. The fixed electrode pad 563P, the first counter electrode pad 581P, and the second counter electrode pad 582P are exposed on the surface viewed from above.

  The movable part 521 is formed to have a thickness dimension larger than that of the holding part 522. For example, in this embodiment, the movable part 521 is formed to be 200 μm, which is the same dimension as the thickness dimension of the movable substrate 52. In addition, the movable portion 521 is formed to have a diameter larger than at least the diameter of the outer peripheral edge of the fixed electrode 561 in the filter plan view. The surface of the movable portion 521 that faces the fixed substrate 51 is a movable surface 521A that is parallel to the reflective film fixed surface 512A. The movable surface 521A is opposed to the fixed reflective film 54 via the inter-reflective film gap G1. The movable electrode 562 facing the movable reflective film 55 and the fixed electrode 561 via the inter-electrode gap G2 is fixed.

As the movable reflective film 55, a reflective film having the same configuration as the above-described fixed reflective film 54 is used. The movable substrate 52 is formed with a reflective film connection electrode 551 extending from the outer peripheral edge of the movable reflective film 55. The reflection film connection electrode 551 extends from the position of the outer peripheral edge of the movable reflection film 55 closest to the vertex C2 toward the vertex C2. The reflective film connection electrode 551 may be any electrode as long as it has conductivity. For example, when the movable reflective film 55 is a conductive metal such as a silver alloy, The reflective film connection electrode 551 can be patterned when the film 55 is formed. In addition, a member different from the movable reflective film 55 may be used. In this case, for example, the reflective film connection electrode 551 is formed of the same material as the movable electrode 562 so that the reflective film connection electrode 551 is patterned when the movable electrode 562 is formed. Can be formed.
The reflective film connection electrode 551 is a first counter electrode 581 (first electrode) formed at the position of the vertex C2 of the fixed substrate 51 by a conductive member 58 such as Ag paste in the vicinity of the outer peripheral edge of the movable substrate 52. One counter electrode pad 581P) is electrically connected. Thereby, it is possible to remove the charge of the movable reflective film 55 from the first counter electrode pad 581P located at the vertex C2 of the fixed substrate 51.

In addition, the movable electrode 562 provided on the movable surface 521A is formed in a C shape in which a portion corresponding to the vertex C2 is opened in a region overlapping with the fixed electrode 561 in the filter plan view. The reflective film connection electrode 551 is formed toward the vertex C2. The width dimension of the movable electrode 562 is the same as the ring width dimension of the fixed electrode 561 (the difference between the radius of the inner periphery and the radius of the outer periphery).
A movable extraction electrode 564 extending from the outer peripheral edge of the movable electrode 562 is formed on the movable substrate 52. The movable extraction electrode 564 extends from the position closest to the vertex C3 of the movable electrode 562 toward the vertex C3. The movable extraction electrode 564 is a second counter electrode 582 (second counter electrode 582) formed at the position of the vertex C 3 of the fixed substrate 51 by a conductive member such as Ag paste in the vicinity of the outer peripheral edge of the movable substrate 52. The electrode pad 582P) is electrically connected.

  Further, the movable portion 521 has an antireflection film (not shown) formed on the surface opposite to the fixed substrate 51. This antireflection film has the same configuration as the antireflection film formed on the fixed substrate 51, and is formed by alternately laminating a low refractive index film and a high refractive index film.

The holding part 522 is a diaphragm surrounding the periphery of the movable part 521. For example, the holding part 522 is formed to have a thickness dimension of 50 μm and is smaller in rigidity in the thickness direction than the movable part 521.
For this reason, the holding part 522 is more easily bent than the movable part 521 and can be bent toward the fixed substrate 51 by a slight electrostatic attraction. At this time, since the movable portion 521 has a thickness dimension larger than that of the holding portion 522 and has a large rigidity, even when a force that bends the movable substrate 52 by electrostatic attraction acts, the movable portion 521 is hardly bent. The bending of the movable reflective film 55 formed on the movable portion 521 can also be prevented.
In this embodiment, the diaphragm-like holding part 522 is illustrated, but the present invention is not limited to this. For example, a configuration in which beam-like holding parts arranged at equiangular intervals around the plane center point O are provided. And so on.

(3-2. Configuration of voltage control means)
The voltage control unit 32 is connected to the fixed electrode pad 563P, the first counter electrode pad 581P, and the second counter electrode pad 582P, and based on a control signal input from the control device 4, the fixed electrode pad 563P, By setting the one counter electrode pad 581P and the second counter electrode pad 582P to a predetermined potential, a voltage is applied to the electrostatic actuator 56 to drive it.
Specifically, the voltage control unit 32 grounds the first counter electrode pad 581P and the fixed electrode pad 563P, and sets the gap G1 between the reflection films to a predetermined dimension with respect to the second counter electrode pad 582P. Set the potential. Accordingly, a voltage is applied between the fixed electrode 561 connected to the fixed electrode pad 563P and the movable electrode 562 connected to the second counter electrode pad 582P, and the movable portion 521 is moved to the fixed substrate 51 side by electrostatic attraction. The dimension of the gap G1 between the reflection films is set to a predetermined value. At this time, since both the first counter electrode pad 581P and the fixed electrode pad 563P are grounded, even if the fixed reflective film 54 and the movable reflective film 55 are charged, the charge can be released, and the fixed reflective film 54 And the electrostatic force due to charging does not act between the movable reflective film 55. Therefore, when setting the gap G1 between the reflection films, the reflection is accurately performed only by setting the voltage between the fixed electrode 561 and the movable electrode 562 without considering the electrostatic force acting between the fixed reflection film 54 and the movable reflection film 55. The inter-film gap G1 can be set to a desired target value.
In this embodiment, the first counter electrode pad 581P and the fixed electrode pad 563P are grounded. However, a predetermined potential may be set. In this case, the set potential of the second counter electrode pad 582P may be set. And the potential difference between the fixed electrode pad 563P and the set potential of the fixed electrode pad 563P is applied to the electrostatic actuator 56 as a drive voltage, and the dimension of the gap G1 between the reflection films can be controlled. Also in this case, by setting the first counter electrode pad 581P and the fixed electrode pad 563P to the same potential, the fixed reflection film 54 and the movable reflection film 55 have the same potential, and the electrostatic potential between the reflection film gaps G1 is increased. The attraction can be eliminated.
The voltage control unit 32 may be configured to ground the second counter electrode pad 582P and set a potential for driving the electrostatic actuator 56 to the first counter electrode pad 581P and the fixed electrode pad 563P. Even in this case, the voltage control unit 32 can drive the electrostatic actuator 56 with an applied voltage based on the potential set to the first counter electrode pad 581P and the fixed electrode pad 563P. In addition, by setting the same potential to the first counter electrode pad 581P and the fixed electrode pad 563P, the electrostatic attractive force does not act between the fixed reflective film 54 and the movable reflective film 55, and the first counter electrode pad 581P. In addition, the gap G1 between the reflective films can be accurately controlled by the potential set to the fixed electrode pad 563P.

[4. Configuration of control device]
The control device 4 controls the overall operation of the color measurement device 1.
As the control device 4, for example, a general-purpose personal computer, a portable information terminal, other color measurement dedicated computer, or the like can be used.
As shown in FIG. 1, the control device 4 includes a light source control unit 41, a colorimetric sensor control unit 42, a colorimetric processing unit 43 that constitutes an analysis processing unit of the present invention, and the like.
The light source control unit 41 is connected to the light source device 2. Then, the light source control unit 41 outputs a predetermined control signal to the light source device 2 based on, for example, a user setting input, and causes the light source device 2 to emit white light with a predetermined brightness.
The colorimetric sensor control unit 42 is connected to the colorimetric sensor 3. The colorimetric sensor control unit 42 sets a wavelength of light received by the colorimetric sensor 3 based on, for example, a user's setting input, and outputs a control signal for detecting the amount of light received at this wavelength. Output to the colorimetric sensor 3. Thereby, the voltage control unit 32 of the colorimetric sensor 3 sets the voltage applied to the electrostatic actuator 56 so as to transmit only the wavelength of light desired by the user based on the control signal.
The colorimetric processing unit 43 analyzes the chromaticity of the inspection object A from the amount of received light detected by the detection unit 31.

[5. (Effects of Embodiment)
As described above, in the wavelength tunable interference filter 5 according to the present embodiment, the fixed substrate 51 has the fixed electrode surface 511A and the reflective film fixing surface 512A having different distances from the movable substrate 52, and is fixed to the fixed electrode surface 511A. An electrode 561 is provided, and the fixed reflective film 54 is provided from the reflective film fixed surface 512A to a part of the fixed electrode surface 511A. And the outer peripheral part of the fixed reflection film 54 is laminated | stacked on the inner peripheral part of the fixed electrode 561, and the laminated part 57 is formed of these laminated bodies. For this reason, even when the fixed reflection film 54 and the fixed electrode 561 are in surface contact with each other in the stacked portion 57, the fixed reflection film 54 and the fixed electrode 561 are electrically connected, and even when the fixed reflection film 54 is charged, Electric charges can be released from the fixed electrode 561. Therefore, generation of electrostatic force due to charging of the fixed reflection film 54 and the movable reflection film 55 can be prevented, and the adjustment of the dimension of the gap G1 between the reflection films by the voltage control unit 32 can be easily and highly accurately performed.
At this time, since the fixed reflective film 54 and the fixed electrode 561 are in surface contact with each other in the stacked portion 57, conduction between the fixed reflective film 54 and the fixed electrode 561 can be reliably ensured, and the charge of the fixed reflective film 54 is transferred to the fixed electrode 561. Can escape. Further, by laminating the fixed reflective film 54 and the fixed electrode 561, the thickness dimension of the laminated portion 57 becomes larger than that of the fixed reflective film 54 and the fixed electrode 561, but the laminated portion 57 has a large distance from the movable substrate 52. Since it is provided on the fixed electrode surface 511A, the variable range of the inter-reflective film gap G1 is not hindered by the thickness of the stacked portion 57, and a sufficient variable region of the inter-reflective film gap G1 is ensured. Can do.

  In the fixed substrate 51, the reflection film fixing surface 512A is formed to protrude from the fixed electrode surface 511A toward the movable substrate 52, and the dimension of the interelectrode gap G2 is larger than the dimension of the reflection film gap G1. For this reason, the variable region of the gap G1 between the reflection films can be increased, and the measurable wavelength region of the colorimetric device 1 can be widened. Further, the electrostatic attraction between the fixed electrode 561 and the movable electrode 562 can be easily controlled, and the dimension of the gap G1 between the reflection films can be set to a desired value with higher accuracy.

  Further, in the stacked portion 57, the fixed reflective film 54 is stacked on the fixed electrode 561. Such a wavelength tunable interference filter 5 can be easily formed by forming a fixed reflection film 54 after forming a fixed electrode 561 at the time of manufacture, and the fixed reflection film 54 is formed as a fixed electrode. Since the film is formed after 561, damage to the fixed reflective film 54 during manufacturing can be suppressed.

A reflective film connection electrode 551 is connected to the movable reflective film 55, and the reflective film connection electrode 551 is connected to the voltage control unit 32 from the first counter electrode pad 581P and grounded. For this reason, even when the movable reflective film 55 is charged, electric charges can be released from the reflective film connection electrode 551, and the generation of an electrostatic force between the fixed reflective film 54 and the movable reflective film 55 can be more reliably prevented. it can.
Further, the potential set to the first counter electrode pad 581P and the fixed electrode pad 563P is not limited to the zero potential due to the ground, and the first counter electrode pad 581P and the fixed electrode pad 563P are set to the same potential by the voltage control unit 32. It only has to be. Even in this case, since the fixed reflection film 54 and the movable reflection film 55 have the same potential, it is possible to prevent electrostatic attraction between the fixed reflection film 54 and the movable reflection film 55.

[Modification of Embodiment]
It should be noted that the present invention is not limited to the above-described embodiments, and modifications, improvements, and the like within the scope that can achieve the object of the present invention are included in the present invention.
For example, in the above embodiment, the first substrate is the fixed substrate 51, and the fixed electrode surface 511A and the reflective film fixing surface 512A formed on the fixed substrate 51 at different height positions are shown. As shown, the first substrate may be a movable substrate 52.
FIG. 4 is a cross-sectional view showing a schematic configuration of a variable wavelength interference filter 5A according to another embodiment.

As shown in FIG. 4, the variable wavelength interference filter 5 </ b> A includes a fixed substrate 51 and a movable substrate 52.
The fixed substrate 51 includes an electrode forming groove 511 having a fixed electrode surface 511A and a reflective film fixing portion 512 having a reflective film fixing surface 512A. Here, unlike the above embodiment, the fixed electrode 561 and the reflective film 54 are provided independently on the fixed electrode surface 511A and the reflective film fixed surface 512A, respectively. Although not shown, the fixed electrode 561 is formed in a substantially C shape in the filter plan view, and the reflection film connection electrode connected to the fixed reflection film 54 is measured on the fixed substrate 51 in the C-shaped opening. The color device 1 is formed to extend toward the vertex (for example, the vertex C2 in FIG. 2).

On the other hand, the movable substrate 52 includes a protruding portion 525 that protrudes from the movable portion 521 toward the fixed substrate 51, and an electrode forming recess 526. Here, the protruding front end surface (projecting surface 525A) of the protruding portion 525 constitutes the first reflecting film fixing surface of the present invention, and the bottom surface 526A of the electrode forming recess 526 constitutes the first electrode surface of the present invention. The bottom surface 526A is formed with a larger distance from the fixed substrate 51 than the protruding surface 525A.
The bottom surface 526A is provided with a movable electrode 562 facing the fixed electrode 561 with an inter-electrode gap G2 at a position overlapping the fixed electrode 561 in the filter plan view. The projecting surface 525A is provided with a movable reflecting film 55 that faces the fixed reflecting film 54 via the inter-reflecting film gap G1, and this movable reflecting film 55 extends from the projecting surface 525A to a part of the bottom surface 526A. Is provided. And the outer peripheral part of the movable reflective film 55 is laminated | stacked on the inner peripheral part of the movable electrode 562, and comprises the laminated part 57A.

  In such a wavelength tunable interference filter 5 </ b> A, similarly to the above-described wavelength tunable interference filter 5, even when the movable reflective film 55 is charged, electric charges can be released to the movable electrode 562. Further, even when the fixed reflection film 54 is charged, the charge can be released by the reflection film connection electrode. Therefore, the electrostatic attractive force does not act between the fixed reflective film 54 and the movable reflective film 55, and the dimension of the gap G1 between the reflective films is accurately set by controlling the voltage applied between the fixed electrode 561 and the movable electrode 562. be able to.

Further, in the above embodiment and the example shown in FIG. 4, an example in which the electrostatic actuator 56 is configured by a pair of electrodes (a fixed electrode 561 and a movable electrode 562) facing each other is shown, but as shown in FIG. 5, The electrostatic actuator 56 may be formed by a plurality of electrodes. FIG. 5 is a cross-sectional view showing a schematic configuration of a wavelength tunable interference filter 5B according to another embodiment.
In the variable wavelength interference filter 5B shown in FIG. 5, the movable electrode 562 is configured by the inner movable electrode 562A and the outer movable electrode 562B. In such a wavelength tunable interference filter 5B, the voltage applied between the inner movable electrode 562A and the fixed electrode 561 and the voltage applied between the outer movable electrode 562B and the fixed electrode 561 are individually controlled, whereby the movable portion 521 is controlled. Can be set with higher accuracy.

  Furthermore, in the above embodiment, as shown in FIG. 3, the reflective film fixing surface 512A facing the movable substrate 52 of the reflective film fixing portion 512 is formed closer to the movable substrate 52 than the fixed electrode surface 511A. Although the example in which the dimension of the gap G2 is larger than the dimension of the gap G1 between the reflective films is shown, the present invention is not limited thereto. The height positions of the fixed electrode surface 511A and the reflective film fixed surface 512A are the wavelength range (measurement wavelength range) of light transmitted by the wavelength tunable interference filter 5, that is, the changeable range of the inter-reflective film gap G1, and the inter-electrode gap It is appropriately set according to the dimension of G2, the thickness dimension of the fixed reflective film 54 and the movable reflective film 55, and the like. Therefore, for example, a configuration may be adopted in which a reflection film fixing groove on the cylindrical concave groove is formed at the center of the fixed electrode surface 511A, and a reflection film fixing surface is formed on the bottom surface of the reflection film fixing groove. In this case, by providing a laminated portion 57 in which the fixed reflective film 54 and the fixed electrode 561 are laminated at the bottom surface portion of the reflective film fixing groove where the distance from the movable substrate 52 is increased, the electrode is formed depending on the thickness dimension of the laminated portion 57. It is possible to avoid the disadvantage that the variable amount of the gap G2 is restricted.

Moreover, in the said embodiment, although the fixed electrode 561 which comprises the electrostatic actuator 56 was illustrated as a 1st electrode, it is not limited to this. For example, a charge removal electrode for removing the charge of the fixed reflection film 54 is provided on the fixed electrode surface 511A of the fixed substrate 51, and the fixed reflection film 54 is laminated on the charge removal electrode to remove the charge. May be.
Also, in the example shown in FIG. 4, the fixed reflection film 54 is connected to a reflection film connection line (not shown), and the charge is removed from the reflection film connection line. A configuration may be adopted in which a charge removal electrode is formed on 511A, and the fixed reflective film 54 is laminated on the charge removal electrode. In this case, a stacked body of the charge removal electrode and the fixed reflective film 54 is formed on the fixed electrode surface 511A having a larger distance from the movable substrate 52 than the reflective film fixed surface 512A. The range in which the gap G1 between the reflection films is not changed by the thickness, and the charge removal electrode and the fixed reflection film 54 are brought into surface contact, so that even when the fixed reflection film 54 is charged, the charge is more reliably released. be able to.

  In the above embodiment and the examples shown in FIGS. 4 and 5, the configuration in which the inter-electrode gap G2 is larger than the inter-reflection film gap G1 is exemplified. However, for example, the inter-electrode gap G2 is smaller than the inter-reflection film gap G1. It is good also as a structure. In this case, the variable range of the inter-reflection film gap G1 is restricted by the inter-electrode gap G2, but this is problematic if sufficient dimensions are secured for the wavelength range to be measured. do not become. However, as described above, the electrostatic attractive force increases in inverse proportion to the square of the distance. Therefore, if the distance between the electrode gaps G2 is reduced, it becomes difficult to control the gap G1 between the reflection films.

In addition, the stacked unit 57 is configured by stacking the fixed reflective film 54 on the fixed electrode 561, but may be configured to stack the fixed electrode 561 on the fixed reflective film 54.
In this case, if a material that easily deteriorates, such as a silver alloy, is used as the fixed reflection film 54, deterioration may occur when the fixed electrode 561 is formed after the formation of the fixed reflection film 54. Masking the reflective film 54 increases the number of processes, but can also suppress degradation. Further, when the fixed reflective film 54 deteriorates, the deterioration usually proceeds from the outer peripheral edge. However, if the outer peripheral edge of the fixed reflective film 54 is covered by the fixed electrode 561, the deterioration of the fixed reflective film 54 proceeds. Can be suppressed.

Although the colorimetric device 1 is exemplified as the electronic apparatus of the present invention, the wavelength variable interference filter, optical module, and electronic apparatus of the present invention can be used in various other fields.
For example, it can be used as a light-based system for detecting the presence of a specific substance. As such a system, for example, an in-vehicle gas leak detector that detects a specific gas with high sensitivity by adopting a spectroscopic measurement method using the variable wavelength interference filter of the present invention, or a photoacoustic rare gas detection for a breath test. A gas detection device such as a vessel can be exemplified.
An example of such a gas detection device will be described below with reference to the drawings.

FIG. 6 is a schematic diagram illustrating an example of a gas detection device including a wavelength variable interference filter.
FIG. 7 is a block diagram showing a configuration of a control system of the gas detection device of FIG.
As illustrated in FIG. 6, the gas detection device 100 includes a sensor chip 110, a flow path 120 including a suction port 120A, a suction flow path 120B, a discharge flow path 120C, and a discharge port 120D, a main body 130, It is configured with.
The main body unit 130 includes a sensor unit cover 131 having an opening to which the flow path 120 can be attached and detached, a discharge unit 133, a housing 134, an optical unit 135, a filter 136, a wavelength variable interference filter 5, a light receiving element 137 (detection unit), and the like. And a control unit 138 for processing a detected signal and controlling the detection unit, a power supply unit 139 for supplying power, and the like. The optical unit 135 emits light, and a beam splitter 135B that reflects light incident from the light source 135A toward the sensor chip 110 and transmits light incident from the sensor chip toward the light receiving element 137. And lenses 135C, 135D, and 135E. In addition, although the structure which uses the wavelength variable interference filter 5 is illustrated, it is good also as a structure which uses the wavelength variable interference filters 5A and 5B mentioned above.
Further, as shown in FIG. 7, an operation panel 140, a display unit 141, a connection unit 142 for interface with the outside, and a power supply unit 139 are provided on the surface of the gas detection device 100. When the power supply unit 139 is a secondary battery, a connection unit 143 for charging may be provided.
Further, as shown in FIG. 7, the control unit 138 of the gas detection apparatus 100 controls a signal processing unit 144 configured by a CPU or the like, a light source driver circuit 145 for controlling the light source 135A, and the variable wavelength interference filter 5. Voltage control unit 146, a light receiving circuit 147 that receives a signal from the light receiving element 137, a sensor chip detection that reads a code of the sensor chip 110 and receives a signal from a sensor chip detector 148 that detects the presence or absence of the sensor chip 110 A circuit 149, a discharge driver circuit 150 for controlling the discharge means 133, and the like are provided.

Next, operation | movement of the above gas detection apparatuses 100 is demonstrated below.
A sensor chip detector 148 is provided inside the sensor unit cover 131 at the upper part of the main body unit 130, and the sensor chip detector 148 detects the presence or absence of the sensor chip 110. When the signal processing unit 144 detects the detection signal from the sensor chip detector 148, the signal processing unit 144 determines that the sensor chip 110 is attached, and displays a display signal for displaying on the display unit 141 that the detection operation can be performed. put out.

  For example, when the operation panel 140 is operated by the user and an instruction signal to start the detection process is output from the operation panel 140 to the signal processing unit 144, the signal processing unit 144 first sends the signal processing unit 144 to the light source driver circuit 145. A light source activation signal is output to activate the light source 135A. When the light source 135A is driven, a linearly polarized laser beam having a single wavelength is emitted from the light source 135A. The light source 135A includes a temperature sensor and a light amount sensor, and the information is output to the signal processing unit 144. When the signal processing unit 144 determines that the light source 135A is stably operating based on the temperature and light quantity input from the light source 135A, the signal processing unit 144 controls the discharge driver circuit 150 to operate the discharge unit 133. Thereby, the gas sample containing the target substance (gas molecule) to be detected is guided from the suction port 120A to the suction channel 120B, the sensor chip 110, the discharge channel 120C, and the discharge port 120D.

The sensor chip 110 is a sensor that incorporates a plurality of metal nanostructures and uses localized surface plasmon resonance. In such a sensor chip 110, an enhanced electric field is formed between the metal nanostructures by laser light, and when gas molecules enter the enhanced electric field, Raman scattered light and Rayleigh scattered light including information on molecular vibrations are generated. Occur.
These Rayleigh scattered light and Raman scattered light enter the filter 136 through the optical unit 135, and the Rayleigh scattered light is separated by the filter 136, and the Raman scattered light enters the wavelength variable interference filter 5. Then, the signal processing unit 144 controls the voltage control unit 146 to adjust the voltage applied to the wavelength variable interference filter 5, and causes the wavelength variable interference filter 5 to split the Raman scattered light corresponding to the gas molecule to be detected. . Thereafter, when the dispersed light is received by the light receiving element 137, a light reception signal corresponding to the amount of received light is output to the signal processing unit 144 via the light receiving circuit 147.
The signal processing unit 144 compares the spectrum data of the Raman scattered light corresponding to the gas molecule to be detected obtained as described above and the data stored in the ROM, and determines whether or not the target gas molecule is the target gas molecule. To determine the substance. Further, the signal processing unit 144 displays the result information on the display unit 141 or outputs the result information from the connection unit 142 to the outside.

  6 and 7 exemplify the gas detection device 100 that performs gas detection from the Raman scattered light obtained by spectrally dividing the Raman scattered light with the variable wavelength interference filter 5. You may use as a gas detection apparatus which specifies gas classification by detecting the light absorbency of. In this case, a gas sensor that allows gas to flow into the sensor and detects light absorbed by the gas in the incident light is used as the optical module of the present invention. A gas detection device that analyzes and discriminates the gas flowing into the sensor by such a gas sensor is an electronic apparatus of the present invention. Even in such a configuration, the gas component can be detected by using the variable wavelength interference filter of the present invention.

In addition, the system for detecting the presence of a specific substance is not limited to the detection of the gas as described above, but a non-invasive measuring device for saccharides by near-infrared spectroscopy, and non-invasive information on food, living body, minerals, etc. A substance component analyzer such as a measuring device can be exemplified.
Hereinafter, a food analyzer will be described as an example of the substance component analyzer.

FIG. 8 is a diagram illustrating a schematic configuration of a food analyzer that is an example of an electronic apparatus using the wavelength variable interference filter 5. Although the wavelength variable interference filter 5 is used here, the wavelength variable interference filters 5A and 5B may be used.
As shown in FIG. 8, the food analyzer 200 includes a detector 210 (optical module), a control unit 220, and a display unit 230. The detector 210 includes a light source 211 that emits light, an imaging lens 212 into which light from the measurement target is introduced, a wavelength variable interference filter 5 that splits the light introduced from the imaging lens 212, and the dispersed light. And an imaging unit 213 (detection unit) for detecting.
In addition, the control unit 220 controls the light source control unit 221 that controls the turning on / off of the light source 211 and the brightness control at the time of lighting, the voltage control unit 222 that controls the wavelength variable interference filter 5, and the imaging unit 213. , A detection control unit 223 that acquires a spectral image captured by the imaging unit 213, a signal processing unit 224, and a storage unit 225.

  In the food analyzer 200, when the system is driven, the light source 211 is controlled by the light source control unit 221, and light is irradiated from the light source 211 to the measurement object. Then, the light reflected by the measurement object enters the wavelength variable interference filter 5 through the imaging lens 212. The variable wavelength interference filter 5 is applied with a voltage capable of dispersing a desired wavelength under the control of the voltage control unit 222, and the dispersed light is imaged by an imaging unit 213 configured by, for example, a CCD camera or the like. The captured light is accumulated in the storage unit 225 as a spectral image. In addition, the signal processing unit 224 controls the voltage control unit 222 to change the voltage value applied to the wavelength tunable interference filter 5, and acquires a spectral image for each wavelength.

Then, the signal processing unit 224 performs arithmetic processing on the data of each pixel in each image accumulated in the storage unit 225, and obtains a spectrum at each pixel. In addition, the storage unit 225 stores, for example, information related to food components with respect to the spectrum, and the signal processing unit 224 analyzes the obtained spectrum data based on the information related to food stored in the storage unit 225. The food component contained in the detection target and the content thereof are obtained. Moreover, a food calorie, a freshness, etc. are computable from the obtained food component and content. Furthermore, by analyzing the spectral distribution in the image, it is possible to extract a portion of the food to be inspected that has reduced freshness, and to detect foreign substances contained in the food. Can also be implemented.
Then, the signal processing unit 224 performs processing for causing the display unit 230 to display information such as the component and content of the food to be inspected and the calories and freshness obtained as described above.

Moreover, although the example of the food analyzer 200 is shown in FIG. 8, it can utilize also as a noninvasive measurement apparatus of the other information as mentioned above by the substantially same structure. For example, it can be used as a biological analyzer for analyzing biological components such as measurement and analysis of body fluid components such as blood. As such a bioanalytical device, for example, a device that detects ethyl alcohol as a device that measures a body fluid component such as blood, it can be used as a drunk driving prevention device that detects the drunk state of the driver. Further, it can also be used as an electronic endoscope system provided with such a biological analyzer.
Furthermore, it can also be used as a mineral analyzer for performing component analysis of minerals.

Furthermore, the wavelength variable interference filter, optical module, and electronic device of the present invention can be applied to the following devices.
For example, by changing the intensity of light of each wavelength over time, it is also possible to transmit data using light of each wavelength. In this case, light of a specific wavelength is transmitted by a wavelength variable interference filter provided in the optical module. The data transmitted by the light of the specific wavelength can be extracted by separating the light and receiving the light at the light receiving unit, and the electronic device equipped with such an optical module for data extraction can be used to extract the light data of each wavelength. By processing, optical communication can be performed.

Further, the electronic apparatus can be applied to a spectroscopic camera, a spectroscopic analyzer, or the like that captures a spectroscopic image by dispersing light with the variable wavelength interference filter of the present invention. An example of such a spectroscopic camera is an infrared camera incorporating a wavelength variable interference filter.
FIG. 9 is a schematic diagram showing a schematic configuration of the spectroscopic camera. As shown in FIG. 9, the spectroscopic camera 300 includes a camera body 310, an imaging lens unit 320, and an imaging unit 330 (detection unit).
The camera body 310 is a part that is gripped and operated by a user.
The imaging lens unit 320 is provided in the camera body 310 and guides incident image light to the imaging unit 330. In addition, as shown in FIG. 9, the imaging lens unit 320 includes an objective lens 321, an imaging lens 322, and a wavelength variable interference filter 5 provided between these lenses.
The imaging unit 330 includes a light receiving element, and images the image light guided by the imaging lens unit 320.
In such a spectroscopic camera 300, a spectral image of light having a desired wavelength can be captured by transmitting light having a wavelength to be imaged by the variable wavelength interference filter 5.

Furthermore, the wavelength tunable interference filter of the present invention may be used as a bandpass filter. For example, only light in a narrow band centered on a predetermined wavelength out of light in a predetermined wavelength range emitted from the light emitting element can be wavelength-variable. It can also be used as an optical laser device that spectrally transmits through an interference filter.
In addition, the tunable interference filter of the present invention may be used as a biometric authentication device, and can be applied to authentication devices such as blood vessels, fingerprints, retinas, and irises using light in the near infrared region and visible region.

  Furthermore, an optical module and an electronic device can be used as a concentration detection device. In this case, the infrared energy (infrared light) emitted from the substance is spectrally analyzed by the variable wavelength interference filter, and the analyte concentration in the sample is measured.

  As described above, the tunable interference filter, the optical module, and the electronic device of the present invention can be applied to any device that splits predetermined light from incident light. Since the wavelength tunable interference filter according to the present invention can split a plurality of wavelengths with one device as described above, it is possible to accurately measure a spectrum of a plurality of wavelengths and detect a plurality of components. it can. Therefore, compared with the conventional apparatus which takes out a desired wavelength with multiple devices, size reduction of an optical module or an electronic device can be promoted, and for example, it can be suitably used as a portable or vehicle-mounted optical device.

  In addition, the specific structure for carrying out the present invention can be appropriately changed to another structure or the like as long as the object of the present invention can be achieved.

  DESCRIPTION OF SYMBOLS 1 ... Color measuring apparatus (electronic device), 3 ... Color measuring sensor (optical module), 5, 5A, 5B ... Wavelength variable interference filter, 31 ... Detection part, 32 ... Voltage control part, 51 ... Fixed board | substrate (1st board | substrate) ), 52... Movable substrate (second substrate), 54... Fixed reflection film (first reflection film), 55... Movable reflection film (second reflection film), 57 and 57 A. One electrode surface) 512A ... Reflective film fixed surface (first reflective film fixed surface), 551 ... Reflective film connection electrode, 561 ... Fixed electrode (first electrode), 562 ... Movable electrode (second electrode), G1 ... Reflective Gap between films, G2 ... Gap between electrodes.

The wavelength tunable interference filter of the present invention includes a first substrate, a second substrate disposed to face the first substrate, and a first reflection disposed between the first substrate and the second substrate. A second reflective film disposed between the second substrate and the first reflective film; and a first electrode for removing the charge of the first reflective film, the second substrate When viewing the first substrate side from the first side, the first region where the first reflective film and the second reflective film overlap, and at least a part of the first reflective film and the first electrode overlap. And a distance between the first substrate and the second substrate in the second region is greater than a distance between the first substrate and the second substrate in the first region. It is large.
In the variable wavelength interference filter according to the aspect of the invention, it is preferable that the second region is disposed outside the first region when the first substrate side is viewed from the second substrate side.
In the wavelength tunable interference filter according to the aspect of the invention, it is preferable that the first electrode is disposed between the first reflective film and the first substrate in the second region.
In the wavelength tunable interference filter according to the aspect of the invention, the first substrate includes a first surface, a second surface arranged to face the first surface of the first region, and the second region. A third surface disposed to face the first surface, and a distance between the second substrate and the third surface is greater than a distance between the second substrate and the second surface Preferably, it is also characterized by being large.
In the wavelength tunable interference filter according to the aspect of the invention, it is preferable that the first reflective film is disposed so as to be in contact with the second surface, and the first electrode is disposed so as to be in contact with the third surface.

A wavelength tunable interference filter according to a related art of the present invention includes a first substrate, a second substrate facing the first substrate, and a first reflection provided on a surface of the first substrate facing the second substrate. A second reflective film provided on a surface of the second substrate facing the first substrate and facing the first reflective film via a gap between the reflective films; and the second substrate of the first substrate A first electrode provided on a surface opposed to the first substrate, wherein the first substrate is provided with a first reflection film fixing surface on which the first reflection film is provided, and the first electrode is provided on the second substrate. A first electrode surface different from the first reflection film fixing surface, and a surface having a large distance from the second substrate among the first reflection film fixing surface and the first electrode surface In addition, a laminated portion in which the first reflective film and the first electrode are laminated is provided.
According to the related technology , the first reflective film and the first electrode are formed by laminating the first reflective film fixing surface and the first electrode surface of the first substrate on a surface having a large distance from the second substrate. A laminated portion is provided, and the first reflective film and the first electrode are brought into surface contact and electrically conducted by the laminated portion. Thereby, even when the first reflective film is charged, the staying charge can be released from the first electrode, and the generation of electrostatic force due to charging between the first reflective film and the second reflective film can be prevented.
Here, it is also conceivable that the end edge of the first electrode and the end edge of the first reflective film are brought into contact with each other for electrical conduction. However, in this case, since the contact area is small and the conduction reliability is low, there is a possibility that the charge of the first reflective film cannot be surely released to the first electrode. In contrast, as described above, by laminating the first electrode and the first reflective film and providing the laminated portion, the first electrode and the first reflective film are surely brought into surface contact and electrically conducted. be able to.
Furthermore, in this related technology , the laminated portion is provided on one surface having a large distance from the second substrate among the first reflecting film fixing surface and the first electrode surface. For this reason, the amount of change in the gap between the reflective films and the gap between the electrodes is not suppressed by the stacked portion. Therefore, it is possible to prevent the disadvantage that the wavelength range that can be extracted by the wavelength tunable interference filter is narrowed.

In the wavelength tunable interference filter according to the related art of the present invention, the second substrate is provided on a surface of the second substrate facing the first substrate, and the first electrode and the first electrode through a gap between the electrodes that is larger than the gap between the reflective films. The second electrode is opposed to each other, and the laminated portion is formed by laminating the first reflective film extending from the first reflective film fixing surface to the first electrode surface and an outer peripheral edge of the first electrode. It is preferable to be configured.
In the wavelength tunable interference filter, the wavelength extracted by transmitting or reflecting is determined by the gap between the reflecting films between the first reflecting film and the second reflecting film. Therefore, in order to acquire the transmission or reflection wavelength corresponding to a wider wavelength range in the wavelength tunable interference filter, it is necessary to increase the fluctuation range of the gap between the reflection films. Here, when a voltage is applied between the first electrode and the second electrode and the gap between the reflective films is changed by electrostatic attraction, if the gap between the electrodes is smaller than the gap between the reflective films, the gap between the electrodes is The gap between the reflective films can be changed only between the two. In such a configuration, the fluctuation range of the gap between the reflection films is reduced, and the wavelength range that can be extracted by the wavelength variable interference filter is reduced.
On the other hand, in this related technique , the gap between the electrodes is formed larger than the gap between the reflection films, so that the gap between the reflection films can be changed in a larger fluctuation range, and it is extracted by the wavelength variable interference filter. Can be widened.
In general, the electrostatic attractive force acting between the electrodes is inversely proportional to the square of the distance. Therefore, if the gap between the electrodes becomes small, it becomes difficult to control the electrostatic attractive force, and it is difficult to adjust the gap between the reflective films. On the other hand, in this related technology , the gap between the electrodes is formed larger than the gap between the reflective films, so that the electrostatic attraction can be easily controlled, and the gap between the reflective films is set to a desired value with high accuracy. Can do.

In the wavelength tunable interference filter according to the related art of the present invention, it is preferable that the stacked portion is configured by stacking the first reflective film on the first electrode.
In this related technology , the laminated portion has a configuration in which the first reflective film is laminated on the first electrode. That is, after the first electrode is formed on the first substrate, the first reflective film is formed. Here, if the first reflective film is formed on the first substrate before forming the first electrode, the first reflective film is likely to be deteriorated when the first electrode is formed, and the resolution of the wavelength variable interference filter is lowered. Problems occur. On the other hand, after forming a 1st electrode in a 1st board | substrate previously, degradation of the 1st reflective film in a manufacturing process can be suppressed by forming a 1st reflective film. Therefore, it is possible to form the first reflective film having good reflection characteristics, and it is possible to suppress a decrease in resolution in the wavelength variable interference filter.

In the variable wavelength interference filter according to the related art of the present invention, it is preferable to include a reflective film connection electrode connected to the second reflective film.
In this related technology , since the reflection film connection electrode is connected to the second reflection film, the charge accumulated in the second reflection film can be released from the reflection film connection electrode, and the first reflection film and the second reflection film It is possible to more reliably prevent the generation of electrostatic force between the two. Therefore, the gap between the reflective films can be controlled with high accuracy by controlling the voltage applied to the first electrode and the second electrode.
Further, the reflective film connection electrode and the first electrode can be set to the same potential, and even in this case, an electrostatic attractive force is not generated between the first reflective film and the second reflective film. The gap can be controlled easily and with high accuracy.

The optical module of the present invention includes the above-described wavelength tunable interference filter of the present invention.
An optical module according to the related art of the present invention includes the above-described variable wavelength interference filter and a detection unit that detects light extracted by the variable wavelength interference filter.
As described above, the wavelength tunable interference filter according to the related technology can release the charge from the first electrode even when the first reflective film is charged, so that no electrostatic force is generated in the gap between the reflective films. The dimension of the gap between the reflective films can be accurately controlled. As a result, the variable wavelength interference filter can extract light having a desired wavelength that is transmitted or reflected with high accuracy. In an optical module equipped with such a tunable interference filter, the amount of light of the desired wavelength extracted by the tunable interference filter is detected by the detection unit, so that the amount of light of the desired wavelength is accurately detected. can do.

In the optical module according to the related technology of the present invention, the wavelength variable interference filter includes a reflective film connection electrode connected to the second reflective film, and the optical module includes the reflective film connection electrode and the first electrode. It is preferable to provide a voltage control unit that makes the same potential.
In this related technology , the voltage control unit sets the reflection film connection electrode connected to the second reflection film and the first electrode to the same potential. As a result, the potential difference between the first reflective film and the second reflective film becomes zero, so that no electrostatic attractive force is generated between the first reflective film and the second reflective film, and the size of the gap between the reflective films is accurately determined. Can be controlled.

Claims (7)

A first substrate;
A second substrate facing the first substrate;
A first reflective film provided on a surface of the first substrate facing the second substrate;
A second reflective film provided on a surface of the second substrate facing the first substrate and facing the first reflective film via a gap between the reflective films;
A first electrode provided on a surface of the first substrate facing the second substrate;
With
The first substrate is
A first reflecting film fixing surface on which the first reflecting film is provided;
The first electrode is provided, and a distance from the second substrate has a first electrode surface different from the first reflecting film fixing surface, and
Of the first reflective film fixing surface and the first electrode surface, a laminated portion in which the first reflective film and the first electrode are laminated is provided on a surface having a large distance from the second substrate. Tunable interference filter. The tunable interference filter according to claim 1,
Provided on a surface of the second substrate facing the first substrate, and having a second electrode facing the first electrode via an inter-electrode gap larger than the gap between the reflective films,
The laminated portion is configured by laminating the first reflective film extending from the first reflective film fixing surface to the first electrode surface and an outer peripheral edge of the first electrode. Tunable interference filter. In the wavelength tunable interference filter according to claim 1 or 2,
The laminated portion is configured by laminating the first reflective film on the first electrode. The variable wavelength interference filter according to claim 1, wherein: In the wavelength variable interference filter according to any one of claims 1 to 3,
A wavelength tunable interference filter, comprising: a reflection film connection electrode connected to the second reflection film. The wavelength variable interference filter according to any one of claims 1 to 4,
A detection unit for detecting light extracted by the variable wavelength interference filter;
An optical module comprising: The optical module according to claim 5,
The wavelength variable interference filter includes a reflective film connection electrode connected to the second reflective film,
The optical module includes a voltage control unit configured to make the reflective film connection electrode and the first electrode have the same potential. An electronic device comprising the optical module according to claim 5.

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