JP2019028205A - Driving device and electronic apparatus - Google Patents

Abstract

To provide a driving device capable of accurately matching a distance between counter members with a target value, and an electronic apparatus.SOLUTION: A driving device comprises: a pair of counter members facing each other; a capacity detection part detecting electrostatic capacitance between the pair of counter members; a gap change part changing a distance between the pair of counter members on the basis of an input signal; a distance maintenance part maintaining the distance between the pair of counter members to a reference distance; and a feedback control part executing feedback control of the input signal on the basis of a first detection value being the electrostatic capacitance detected by the capacity detection part. When the distance between the pair of counter members becomes the reference distance, the feedback control part corrects the first detection value on the basis of a difference between a second detection value being the electrostatic capacitance detected by the capacity detection part and an ideal value of the electrostatic capacitance between the pair of counter members when the distance between the pair of counter members becomes the reference distance, and executes the feedback control.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a drive device and an electronic apparatus.

  2. Description of the Related Art Conventionally, a wavelength variable interference filter including a pair of substrates facing each other, reflective films disposed on each substrate and facing each other, and electrodes disposed on each substrate and facing each other is known ( For example, see Patent Document 1).

  In the variable wavelength interference filter described in Patent Document 1, electrostatic force application electrodes (electrostatic actuators) that face each other are arranged on each substrate. In such a wavelength tunable interference filter, the voltage controller applies a voltage to the electrostatic actuator to change the gap amount (interval size) between the reflective films. In addition, the gap between the reflective films is detected by a gap detector, and the voltage applied from the voltage control unit to the electrostatic actuator is finely adjusted (feedback controlled) based on the detected capacitance. The dimension of the intermembrane gap can be set to a desired target value.

Japanese Patent Laying-Open No. 2015-225148

  By the way, in the wavelength variable interference filter as described in the above-mentioned Patent Document 1, it is connected to the reflection film or the reflection film due to the adhesion of foreign matter to the reflection film or the wiring connected to the reflection film, a change with time, a power supply fluctuation or the like. When the parasitic capacitance of the connected wiring changes, the capacitance detected by the gap detector changes, which causes a problem that feedback control cannot be performed with high accuracy.

  An object of this invention is to provide the drive device and electronic device which can adjust the distance between opposing members to a target value accurately.

  A driving apparatus according to an application example of the invention includes a pair of facing members facing each other, a capacitance detection unit that detects a capacitance between the pair of facing members, and the pair of facing members based on an input signal. A gap changing unit that changes the distance between the members, a distance maintaining unit that maintains a distance between the pair of opposing members at a reference distance, and a first detection that is the capacitance detected by the capacitance detecting unit A feedback control unit that performs feedback control of the input signal based on a value, and the feedback control unit detects the capacitance detection unit when a distance between the pair of opposed members becomes the reference distance. And the ideal value of the capacitance between the pair of opposing members when the distance between the pair of opposing members is the reference distance. Based on the difference before By correcting the first detection value, which comprises carrying out the feedback control.

  According to this application example, the amount of change in the parasitic capacitance can be detected based on the difference between the second detection value and the ideal value when the distance between the opposing members is the reference distance. For this reason, the first detection value is corrected based on the amount of change in the parasitic capacitance, and feedback control is performed based on the corrected first detection value, so that even when the parasitic capacitance changes, highly accurate feedback control And the distance between the opposing members can be accurately adjusted to the target value.

  In the driving device according to this application example, the reference distance is a minimum distance between the pair of opposing members that can be changed by the gap changing unit, and the distance between the pair of opposing members is the reference distance. After changing, it is preferable to increase the distance sequentially.

According to this application example, when the distance between the opposing members is initially set as the reference distance, the amount of change in the parasitic capacitance can be detected, and thereafter, when setting the distance between the opposing members to each target value, The first detection value is corrected by the amount of change in parasitic capacitance, and feedback control can be performed based on the corrected first detection value. For this reason, the distance between opposing members can be accurately adjusted to each target value.
Further, according to this application example, when a series of driving processes for setting the distance between the opposing members to each target value is repeated, the amount of change in parasitic capacitance can be detected each time the driving process is performed. For example, the distance between the opposing members can be accurately adjusted to each target value as compared with the case where the amount of change in the parasitic capacitance is detected only when the power is turned on.

  In the driving device according to this application example, the feedback control unit includes a storage unit that stores relationship data indicating a relationship between the capacitance between the pair of opposing members and a distance between the pair of opposing members. Preferably, the relation data is corrected based on a difference between the second detection value and the ideal value, and the feedback control is performed based on the corrected relation data.

  In this application example, it is possible to accurately grasp the capacitance with respect to the target value of the distance between the opposing members by correcting the relationship data.

  In the driving device according to the application example, the first substrate on which the first mirror is provided, and the second substrate on which the second mirror facing the first mirror is provided and facing the first substrate, The opposing members are preferably the first mirror and the second mirror.

In this application example, the drive device can function as an etalon (Fabry-Perot etalon) by a pair of mirrors, and light having a target wavelength is output by setting the distance between the mirrors to a target value.
According to this application example, the distance between the mirrors that determines the wavelength of the output light can be directly detected and feedback control can be performed, so that light of the target wavelength can be output with higher accuracy.

  In the driving device according to this application example, the distance includes a first substrate on which one of the pair of opposing members is provided, and a second substrate on which the other of the pair of opposing members is provided and faces the first substrate, and the distance The maintenance unit is provided on at least one of the first substrate and the second substrate, and when the distance between the pair of opposing members becomes the reference distance, the first substrate and the second substrate It is preferable that it is a protrusion part which contact | abuts either one.

  According to this application example, the distance between the opposing members is shortened by the gap changing portion until the protruding portion contacts either one of the first substrate and the second substrate, so that the distance between the opposing members becomes the reference distance. Easy to set.

  An electronic apparatus according to an application example of the invention includes the drive device and a control unit that controls the drive device.

  According to the above drive device, the distance between the facing members can be controlled with high accuracy, and therefore the accuracy of various processes associated with the control can be increased in an electronic device including the drive device. For example, a wavelength tunable interference filter can perform highly accurate wavelength control, and a spectroscopic measurement device that detects emitted light by controlling the wavelength tunable interference filter can detect the amount of light of a target wavelength with high accuracy. .

1 is a block diagram showing a schematic configuration of a spectrometer according to a first embodiment of the present invention. The figure which shows schematic structure of the optical module of 1st embodiment. Sectional drawing of the wavelength variable interference filter of 1st embodiment. The top view of the wavelength variable interference filter of 1st embodiment. The conceptual diagram of the closed loop system in the voltage control part of 1st embodiment. The graph which shows the relationship between the electrostatic capacitance between reflecting films, and a peak wavelength. The flowchart which shows the measurement process of 1st embodiment. The transition diagram of the distance between the reflecting films in the measurement process of 1st embodiment. The figure which shows operation | movement of the wavelength tunable filter in the measurement process of 1st embodiment. The figure which shows the structural example of the external appearance of the printer of 2nd embodiment which concerns on this invention. The block diagram which shows schematic structure of the printer of 2nd embodiment.

[First embodiment]
Hereinafter, a spectrometer 1 according to a first embodiment of the present invention will be described with reference to the drawings.
[Configuration of Spectrometer]
FIG. 1 is a block diagram showing a schematic configuration of a spectrometer 1 according to the first embodiment of the present invention.
The spectroscopic measurement apparatus 1 is an electronic apparatus of the present invention, and is an apparatus that analyzes a light intensity of a predetermined wavelength in measurement target light reflected by the measurement target X and measures a spectral spectrum. In this embodiment, an example of measuring the measurement target light reflected by the measurement target X is shown. However, when a light emitter such as a liquid crystal display is used as the measurement target X, the light emitted from the light emitter is measured. The target light may be used.
As shown in FIG. 1, the spectrometer 1 includes an optical module 10, a detector 11 (detection unit), an IV converter 12, an amplifier 13, an A / D converter 14, and a control unit 20. And. The optical module 10 corresponds to the drive device of the present invention, and includes the variable wavelength interference filter 5 and the voltage control unit 15.

The detector 11 receives the light transmitted through the wavelength variable interference filter 5 of the optical module 10 and outputs a detection signal (current) corresponding to the light intensity of the received light.
The IV converter 12 converts the detection signal input from the detector 11 into a voltage value and outputs the voltage value to the amplifier 13.
The amplifier 13 amplifies a voltage (detection voltage) corresponding to the detection signal input from the IV converter 12.
The A / D converter 14 converts the detection voltage (analog signal) input from the amplifier 13 into a digital signal and outputs it to the control unit 20.
Based on the control of the control unit 20, the voltage control unit 15 drives the wavelength variable interference filter 5 and transmits light having a predetermined target wavelength from the wavelength variable interference filter 5.

[Configuration of optical module]
Next, the configuration of the optical module 10 will be described below.
FIG. 2 is a block diagram illustrating a schematic configuration of the optical module 10.
As described above, the optical module 10 includes the variable wavelength interference filter 5 and the voltage control unit 15.

[Configuration of wavelength tunable interference filter]
The wavelength variable interference filter 5 of the optical module 10 will be described below. FIG. 3 is a cross-sectional view illustrating a schematic configuration of the wavelength variable interference filter 5. FIG. 4 is a plan view showing a schematic configuration of the variable wavelength interference filter 5.
As shown in FIGS. 3 and 4, the variable wavelength interference filter 5 is a rectangular plate-shaped optical member, for example, and includes a fixed substrate 51 (first substrate) and a movable substrate 52 (second substrate). The fixed substrate 51 and the movable substrate 52 are formed of an insulating material such as various types of glass or quartz, and are bonded by a bonding film 53 (see FIG. 3) formed of, for example, a plasma polymerized film mainly containing siloxane. By doing so, it is configured integrally.

The fixed substrate 51 is provided with a fixed reflective film 54 (first mirror), and the movable substrate 52 is provided with a movable reflective film 55 (second mirror). The fixed reflection film 54 and the movable reflection film 55 are disposed to face each other via a gap G1 (see FIG. 3). That is, the fixed reflective film 54 and the movable reflective film 55 correspond to a pair of opposing members of the present invention.
The fixed substrate 51 is provided with a fixed electrode 561, and the movable substrate 52 is provided with a movable electrode 562. The fixed electrode 561 and the movable electrode 562 are arranged to face each other with a predetermined gap. These fixed electrode 561 and movable electrode 562 constitute an electrostatic actuator 56 which is a gap changing portion of the present invention.
In the following description, the wavelength tunable interference filter 5 was seen from a plan view seen from the thickness direction of the fixed substrate 51 or the movable substrate 52, that is, from the stacking direction of the fixed substrate 51, the bonding film 53, and the movable substrate 52. The plan view is referred to as a filter plan view. In the present embodiment, the center point of the fixed reflection film 54 and the center point of the movable reflection film 55 coincide with each other in the filter plan view, and the center point of these reflection films in the plan view is referred to as a filter center point O. A straight line passing through the center point of these reflective films is referred to as a central axis.

(Configuration of fixed substrate)
As shown in FIG. 3, the fixed substrate 51 includes an electrode arrangement groove 511 and a reflective film installation portion 512 formed by, for example, etching. Moreover, one end side (side C1-C2 in FIG. 4) of the fixed substrate 51 protrudes outward from the substrate edge (side C5-C6 in FIG. 4) of the movable substrate 52, and the first terminal extraction portion 514 is formed. It is composed.

The electrode arrangement groove 511 is formed in an annular shape centering on the filter center point O of the fixed substrate 51 in the filter plan view. The reflection film installation part 512 is formed so as to protrude from the center part of the electrode arrangement groove 511 toward the movable substrate 52 in the filter plan view. On the groove bottom surface 511A of the electrode arrangement groove 511, a fixed electrode 561 of the electrostatic actuator 56 and a first pillar portion 571 constituting a part of a distance maintaining portion that maintains the distance of the gap G1 at the reference distance are provided. ing. In addition, a fixed reflective film 54 is provided on the protruding front end surface of the reflective film installation portion 512.
The fixed substrate 51 is provided with an electrode lead groove (not shown) extending from the electrode placement groove 511 toward the outer peripheral edge of the fixed substrate 51.

The fixed electrode 561 is formed, for example, in an arc shape (substantially C shape), and as shown in FIG. 4, a C-shaped opening is provided in a part close to the side C1-C2. In addition, an insulating film for ensuring insulation between the movable electrode 562 and the fixed electrode 561 may be stacked.
The fixed electrode 561 includes a fixed extraction electrode 563 extending to the first terminal extraction portion 514 along the electrode extraction groove. The extended leading end portion of the fixed extraction electrode 563 is connected to the voltage control unit 15 by, for example, a lead wire or FPC (Flexible printed circuits).

The fixed reflective film 54 provided on the protruding front end surface of the reflective film installation part 512 is made of a conductive reflective film material such as a metal film such as Ag or an Ag alloy. As the fixed reflective film 54, for example, a dielectric multilayer film in which the high refractive layer is TiO ₂ and the low refractive layer is SiO ₂ may be used. In the case where a dielectric multilayer film is used as the fixed reflective film 54, conductivity is imparted by laminating a conductive film on the lowermost layer or the uppermost layer (surface layer) of the dielectric multilayer film. As this conductive film, for example, a reflective film such as an Ag alloy having a high reflectance characteristic with respect to a wide wavelength range may be used. In this case, the conductive film can widen the wavelength range to be measured of the wavelength tunable interference filter 5, it is possible to take out a desired target wavelength with respect to a wide wavelength band, and the dielectric multilayer film increases the wavelength. It becomes possible to extract light of a target wavelength with resolution. In addition, a transparent adhesive layer may be further interposed between the conductive film and the reflective film installation portion 512 or between the conductive film and the dielectric multilayer film in order to improve adhesion.

As shown in FIG. 4, the fixed substrate 51 is connected to the outer peripheral edge of the fixed reflection film 54, passes through the C-shaped opening of the fixed electrode 561, and extends toward the first terminal extraction portion 514. One mirror electrode 541 is provided. The first mirror electrode 541 is formed by being formed simultaneously with the formation of the fixed reflective film 54.
The first mirror electrode 541 is connected to the voltage control unit 15 on the first terminal extraction unit 514.

The first pillar portion 571 (the protruding portion of the present invention) is provided on the filter center point O side of the fixed electrode 561 outside the fixed reflection film 54 in the electrode arrangement groove 511 in the filter plan view, and the filter center point They are arranged at regular intervals on the circumference of a virtual circle centered on O. The first pillar portion 571 may be provided in an annular shape with the filter center point O as the center, for example.
As shown in FIG. 3, the height dimension from the groove bottom surface 511 </ b> A of the electrode arrangement groove 511 of the first pillar part 571 is formed to be larger than the combined thickness dimension of the reflective film installation part 512 and the fixed reflective film 54. ing.
The material for forming the first pillar portion 571 is not particularly limited, and may be made of, for example, the same material as that of the fixed substrate 51 or SiO ₂ . In the present embodiment, the base end portion 571A that is a part of the first pillar portion 571 is integrally formed with the fixed substrate 51, and the tip end portion 571B that is the remaining portion is made of SiO ₂ or the like. In this case, the electrode placement groove 511, the reflective film installation part 512, and the base end part 571A are formed by performing a two-stage etching process on the fixed substrate 51, and SiO ₂ or the like is formed on the base end part 571A. The first pillar portion 571 can be formed by forming the layer and providing the tip portion 571B.

  Of the fixed substrate 51, the electrode placement groove 511, the reflective film installation portion 512, and the region where the electrode lead-out groove is not formed are bonded to the movable substrate 52 by the bonding film 53.

(Configuration of movable substrate)
The movable substrate 52 includes a circular movable portion 521 centered on the filter center point O in the filter plan view as shown in FIG. 4, a holding portion 522 that is coaxial with the movable portion 521 and holds the movable portion 521, A substrate outer peripheral portion 525 provided outside the holding portion 522.
Moreover, in the movable substrate 52, as shown in FIG. 4, one end side (side C7-C8) protrudes outward from the substrate edge (side C3-C4) of the fixed substrate 51, and the second terminal extraction portion 524 is configured.

  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 have the same dimension as the thickness dimension of the movable substrate 52. The movable portion 521 is formed to have a diameter that is larger than at least the diameter of the outer peripheral edge of the reflective film installation portion 512 in the filter plan view. The movable surface 521A of the movable portion 521 facing the fixed substrate 51 is provided with a movable reflective film 55, a movable electrode 562, and a second pillar portion 572 that constitutes a part of the distance maintaining portion.

The movable electrode 562 is provided on the outer peripheral side of the movable reflective film 55 in the plan view of the filter, and is disposed to face the fixed electrode 561 with a gap. The movable electrode 562 is formed in an arc shape (substantially C shape), and as shown in FIG. 4, a C-shaped opening is provided in a part close to the sides C7 to C8. Similarly to the fixed electrode 561, an insulating film may be stacked over the movable electrode 562.
Here, as shown in FIG. 4, the electrostatic actuator 56 is configured by an arc region where the movable electrode 562 and the fixed electrode 561 overlap with each other in the filter plan view (a region indicated by a hatched portion rising to the right in FIG. 4). Yes. As shown in FIG. 4, the electrostatic actuator 56 has a shape and an arrangement that are symmetrical with respect to the filter center point O in the filter plan view. Therefore, the electrostatic attractive force generated when a voltage is applied to the electrostatic actuator 56 also acts on a position that is point-symmetric with respect to the filter center point O, and displaces the movable portion 521 toward the fixed substrate 51 in a balanced manner. Is possible.

  Further, as shown in FIG. 4, the movable electrode 562 is provided with a movable extraction electrode 564 extending toward the second terminal extraction portion 524. The movable extraction electrode 564 is disposed along a position facing the electrode extraction groove provided on the fixed substrate 51. In addition, the extended leading end portion of the movable extraction electrode 564 is connected to the voltage control unit 15 by, for example, an FPC or a lead wire.

The movable reflective film 55 is provided in the central part of the movable surface 521A of the movable part 521 so as to face the fixed reflective film 54 via the gap G1. As the movable reflective film 55, a reflective film having the same configuration as that of the fixed reflective film 54 described above is used. In the present embodiment, the gap G1 between the reflective films 54 and 55 is smaller than the gap between the electrodes 561 and 562.
Further, as shown in FIG. 4, the movable substrate 52 is connected to the outer peripheral edge of the movable reflective film 55, passes through the C-shaped opening of the movable electrode 562, and extends toward the second terminal extraction portion 524. Two mirror electrodes 551 are provided.
In the case where the movable reflective film 55 is composed of a laminate of a dielectric multilayer film and a conductive film, the second mirror electrode 551 is formed at the same time as the conductive film and is connected to the conductive film.
The second mirror electrode 551 is connected to the voltage control unit 15 on the second terminal extraction unit 524 by, for example, an FPC or a lead wire.

The second pillar portion 572 (protruding portion of the present invention) is provided on the filter center point O side of the movable electrode 562 outside the movable reflective film 55 in the filter plan view, and faces the first pillar portion 571.
Similar to the first pillar portion 571, the second pillar portions 572 are arranged at equal intervals on the circumference of a virtual circle centered on the filter center point O in the filter plan view. Note that the second pillar portion 572 may be formed in an annular shape.
The second pillar portion 572 is formed such that the height dimension from the movable surface 521A facing the fixed substrate 51 of the movable section 521 is larger than the film thickness dimension of the movable reflective film 55. That is, the size of the gap G2 between the first pillar portion 571 and the second pillar portion 572 is smaller than the size of the gap G1 between the reflective films 54 and 55.
A material for forming the second pillar portion 572 is not particularly limited, and may be made of, for example, the same material as the movable substrate 52 or SiO ₂ . In the present embodiment, the second pillar portion 572 is constituted by SiO _2.

The holding part 522 is a diaphragm that surrounds the periphery of the movable part 521, and has a thickness dimension smaller than that of the movable part 521. Such a holding part 522 is easier to bend than the movable part 521, and the movable part 521 can be displaced 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 rigidity, the shape change of the movable portion 521 is suppressed even when the holding portion 522 is pulled toward the fixed substrate 51 by electrostatic attraction. Is done. Therefore, the movable reflective film 55 provided on the movable portion 521 is hardly bent, and the fixed reflective film 54 and the movable reflective film 55 can be always maintained in a parallel state.
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 filter center point O are provided. And so on.

  As described above, the substrate outer peripheral portion 525 is provided outside the holding portion 522 in the filter plan view. The surface of the substrate outer peripheral portion 525 that faces the fixed substrate 51 is bonded to the fixed substrate 51 through the bonding film 53.

[Configuration of voltage controller]
As shown in FIG. 2, the voltage control unit 15 includes a gap detector 151 (capacitance detection unit in the present invention), a filter driving unit 152, and a microcomputer (microcontroller) 16. The voltage control unit 15 applies a driving voltage to the electrostatic actuator 56 in accordance with a control signal from the control unit 20, and sets the dimension of the gap G1 between the reflective films to a desired value.
Hereinafter, the configuration of the voltage control unit 15 will be described in detail.

FIG. 5 is a conceptual diagram of a feedback loop using the voltage control unit 15.
As shown in FIG. 5, the voltage control unit 15 includes a closed loop system 15 </ b> L (feedback loop) by the electrostatic actuator 56, the gap detector 151, and the filter driving unit 152 of the variable wavelength interference filter 5. In the present embodiment, the microcomputer 16 suitably maintains the control state during the feedback control by setting the gain of the closed loop system 15L based on the drive characteristics of the electrostatic actuator 56.

The gap detector 151 is connected to the first mirror electrode 541 and the second mirror electrode 551 of the wavelength variable interference filter 5. The gap detector 151 detects the size of the gap G1 between the reflective films 54 and 55, which varies depending on the driving of the electrostatic actuator 56, and outputs a detection signal. By detecting the size of the gap G1, the driving amount of the electrostatic actuator 56 can be easily calculated.
For example, the gap detector 151 detects the electrostatic capacitance between the reflection films 54 and 55 and outputs the detection value (first detection value) to the filter driving unit 152 and the microcomputer 16 as a voltage signal (detection signal).
The gap detector 151 may output an analog signal or a digital signal as a detection signal. In the case of outputting a digital signal, a detection signal (analog signal) is input to an ADC (Analog to Digital Converter) and converted into a digital value.

The filter driving unit 152 is connected to the fixed extraction electrode 563 and the movable extraction electrode 564 of the variable wavelength interference filter 5. The filter driving unit 152 applies a driving voltage (input signal) to the electrostatic actuator 56 based on a target signal for setting the gap G1 input from the microcomputer 16 to a predetermined target value.
At this time, the filter driving unit 152 refers to the gap correlation data (relation data) indicating the relationship between the capacitance and the size of the gap G1 with respect to the capacitance output from the gap detector 151. Convert to The gap correlation data is stored in the memory 161 of the microcomputer 16 described later. Then, the filter drive unit 152 sets the drive voltage for the electrostatic actuator 56 so that the deviation between the converted size of the gap G1 and the size of the gap G1 indicated by the target signal input from the microcomputer 16 is equal to or less than a predetermined threshold value. Increase and decrease to control. That is, the filter driving unit 152 performs feedback control based on the detection signal and the target signal. That is, the filter drive unit 152, the gap detector 151 that outputs the detection signal, and the microcomputer 16 that outputs the target signal constitute the feedback control unit of the present invention.

  Returning to FIG. 2, the microcomputer 16 includes a memory 161 as a storage unit, and the memory 161 includes a gap indicating the relationship between the capacitance detected by the gap detector 151 and the size of the gap G1, as described above. Correlation data is stored.

Here, for example, the reflection films 54 and 55 and the reflection films 54 and 55 are connected to the reflection films 54 and 55 due to adhesion of foreign matters to the reflection films 54 and 55 and wiring connected to the reflection films 54 and 55, changes with time, power fluctuations, and the like. In some cases, the parasitic capacitance of the connected wiring changes, and the relationship between the capacitance detected by the gap detector 151 and the size of the gap G1 changes. In this case, feedback control is not appropriately performed, and the peak wavelength of the light output from the wavelength variable interference filter 5 may not be set as the target wavelength.
FIG. 6 is a graph showing the relationship between the capacitance and the peak wavelength when the parasitic capacitance is a reference value and when the parasitic capacitance varies from the reference value. A curve P1 shows the relationship when the parasitic capacitance is a reference value, and a curve P2 shows the relationship when the parasitic capacitance varies from the reference value. As shown in FIG. 6, even when the capacitance is the same, when the parasitic capacitance varies from the reference value, the peak wavelength is longer than when the parasitic capacitance is the reference value.
For this reason, in this embodiment, the microcomputer 16 includes a correction unit 162 that corrects the gap correlation data. A method for correcting the gap correlation data by the correction unit 162 will be described later.

Further, the microcomputer 16 functions as a drive control unit 163 as shown in FIG.
When the wavelength setting command related to the target wavelength is input as a control signal from the control unit 20, the drive control unit 163 calculates the size (target value) of the gap G 1 corresponding to the target wavelength, and sends the target signal to the filter driving unit 152. Output.

[Configuration of control unit]
Returning to FIG. 1, the control unit 20 of the spectroscopic measurement apparatus 1 will be described.
The control unit 20 is configured by combining a CPU, a memory, and the like, for example, and controls the overall operation of the spectroscopic measurement apparatus 1. As shown in FIG. 1, the control unit 20 includes a filter control unit 21, a light amount acquisition unit 22, a spectroscopic measurement unit 23, and a storage unit 30.
The storage unit 30 stores various programs for controlling the spectroscopic measurement apparatus 1 and various data.

The filter control unit 21 outputs a control signal for correcting the gap correlation data to the voltage control unit 15.
Further, the filter control unit 21 sets a target wavelength of light extracted by the variable wavelength interference filter 5 and outputs a control signal for setting the size of the gap G1 to the size of the gap G1 corresponding to the set target wavelength. Output to the control unit 15.

The light quantity acquisition unit 22 acquires the light quantity of the target wavelength light transmitted through the wavelength variable interference filter 5 based on the light quantity acquired by the detector 11.
The spectroscopic measurement unit 23 measures the spectral characteristics of the light to be measured based on the light amount acquired by the light amount acquisition unit 22.

[Spectral measurement processing]
Next, a spectroscopic measurement process using the spectroscopic measurement apparatus 1 of the present embodiment will be described based on the drawings.
FIG. 7 is a flowchart showing the spectroscopic measurement process of the present embodiment. FIG. 8 is a transition diagram of the dimension of the gap G1 in the spectroscopic measurement process of the present embodiment.
For example, when the spectroscopic measurement process is started by an operation of the measurer, the filter control unit 21 of the control unit 20 outputs a control signal for correcting the gap correlation data to the microcomputer 16.

When the control signal is input, the correction unit 162 of the microcomputer 16 controls the filter driving unit 152 to apply a predetermined voltage to the electrostatic actuator 56, and as shown in FIG. The second pillar portion 572 is brought into contact. Thereby, the distance of the gap G1 is set to the reference distance (step S1). That is, in this embodiment, the reference distance is set to the minimum distance of the gap G1.
In the present embodiment, the reference distance is set to a distance smaller than the distance of the gap G1 corresponding to the shortest wavelength among the target wavelengths. For example, the reference distance corresponds to the shortest wavelength. It may be the same as the distance of the gap G1.
Further, when the predetermined voltage is applied to the electrostatic actuator 56, the movable substrate 52 moves in a direction approaching the fixed substrate 51, and then the second pillar portion 572 comes into contact with the first pillar portion 571, so that the movable portion 521 stops immediately without vibrating. Thereby, the gap G1 can be quickly set to the reference distance.

  Next, in a state where the distance of the gap G1 is maintained at the reference distance, the gap detector 151 detects the capacitance between the reflection films 54 and 55, and the correction unit 162 detects the detected capacitance (second detection). Value) is acquired (step S2). Then, the correction unit 162 calculates the difference between the acquired second detection value and the ideal value (step S3). The ideal value is a capacitance value (reference value) when the distance of the gap G1 is a reference distance measured at the time of shipment, for example, and is stored in the memory 161, for example.

  Next, the correction unit 162 corrects the gap correlation data stored in the memory 161 based on the difference between the second detection value and the ideal value (second detection value−ideal value) (step S4). Specifically, the correction unit 162 calculates a value obtained by adding the difference to the initial value of the capacitance, and updates each capacitance in the gap correlation data with the calculated value. As a result, the gap correlation data can be corrected to a value reflecting the change in parasitic capacitance.

Next, the filter control unit 21 outputs a command for setting the shortest wavelength (for example, 400 nm) among the target wavelengths to the microcomputer 16. As a result, the drive control unit 163 outputs a target signal with the dimension of the gap G1 corresponding to the shortest wavelength as a target value to the filter drive unit 152.
Then, the filter drive unit 152 sets the drive voltage for the electrostatic actuator 56 so that the deviation between the detection signal output from the gap detector 151 and the target signal input from the drive control unit 163 is equal to or less than a predetermined threshold. Increase and decrease to control. At this time, the filter driving unit 152 converts the capacitance (first detection value) between the reflective films 54 and 55 detected by the gap detector 151 into the size of the gap G1 with reference to the corrected gap correlation data. And compare with the target signal. That is, according to this, feedback control can be implemented by correcting the first detection value based on the amount of change in parasitic capacitance.
As a result, the gap G1 is set to a dimension corresponding to the shortest wavelength with high accuracy (step S5), and the light having the shortest wavelength is transmitted from the wavelength variable interference filter 5 and received by the detector 11.

Next, the light quantity acquisition unit 22 of the control unit 20 acquires the light quantity of the light received by the detector 11 as the measurement light quantity, and stores it in the storage unit 30 (step S6).
Thereafter, the control unit 20 determines whether or not the measurement light amounts of light of all target wavelengths have been acquired (step S7).

When it is determined NO in step S <b> 7, the filter control unit 21 outputs a command to set the next longest wavelength among the target wavelengths to the microcomputer 16. Accordingly, the gap G1 is set to a size corresponding to the next longest wavelength by the drive control unit 163 and the filter drive unit 152 (step S8), and the light having the next longest wavelength is transmitted from the wavelength variable interference filter 5, The light is received by the detector 11.
Then, the process returns to step S <b> 6, and the light amount acquisition unit 22 acquires the light amount of the light received by the detector 11 as the measurement light amount and stores it in the storage unit 30.
In this way, the processes in steps S6 to S8 are repeatedly executed until it is determined in step S7 that the measurement light quantities of the light of all target wavelengths have been acquired. That is, the size of the gap G1 is sequentially increased, and the amount of light transmitted from the wavelength variable interference filter 5 is measured and stored in the storage unit 30 each time the size of the gap G1 is increased.

  Then, when the measurement of the longest wavelength (for example, 700 nm) among the target wavelengths is completed, YES is determined in step S7, and the spectroscopic measurement unit 23 of the control unit 20 is based on the light amount acquired by the light amount acquisition unit 22. The spectral characteristic of the measurement target light is measured (step S9).

[Operational effects of the first embodiment]
In the present embodiment, the correction unit 162 corrects the gap correlation data based on the difference between the capacitance (second detection value) and the ideal value when the distance of the gap G1 is the reference distance. Can be corrected based on the amount of change in parasitic capacitance. Therefore, even when the parasitic capacitance changes, highly accurate feedback control can be performed, and the size of the gap G1 can be accurately adjusted to the target value. Thereby, the light quantity of the light of the target wavelength can be detected with high accuracy.

  In the present embodiment, when the distance of the gap G1 is first set as the reference distance in the spectroscopic measurement process, the amount of change in the parasitic capacitance is detected, and thereafter, the distance of the gap G1 is sequentially increased and set to each target value. In this case, the first detection value can be corrected with the change amount of the parasitic capacitance, and feedback control can be performed based on the corrected first detection value. For this reason, the dimension of the gap G1 can be accurately adjusted to each target value.

  In the present embodiment, since the size of the gap G1, which is the distance between the reflective films 54 and 55 that determines the wavelength of the output light, is directly detected and feedback control is performed, the light of the target wavelength is output with higher accuracy. Can be made.

  In the present embodiment, the distance of the gap G1 can be easily set to the reference distance by shortening the dimension of the gap G1 by the electrostatic actuator 56 until the second pillar 572 contacts the first pillar 571.

[Second Embodiment]
Next, an embodiment in which the spectrometer 1 of the first embodiment is mounted on a printer 6 (inkjet printer) will be described below as a second embodiment.

[Schematic configuration of printer]
FIG. 10 is a diagram illustrating a configuration example of the appearance of the printer 6 according to the present embodiment. FIG. 11 is a block diagram illustrating a schematic configuration of the printer 6 according to the present embodiment.
10 and 11, the printer 6 includes a supply unit 61, a transport unit 62, a carriage 63, a carriage moving unit 64, and a control unit 65 (see FIG. 11). The printer 6 controls each unit 61, 62, 64 and the carriage 63 based on print data input from an external device 70 such as a personal computer, for example. An image is printed on top (referred to as A1). Further, the printer 6 of the present embodiment forms a color patch for color measurement at a predetermined position on the media surface A1 based on preset calibration print data, and performs spectral measurement on the color patch. As a result, the printer 6 compares the actual measurement value for the color patch with the calibration print data to determine whether or not the printed color has color misregistration. To correct the color.
Hereinafter, each configuration of the printer 6 will be specifically described.

The supply unit 61 is a unit that supplies the medium A that is an image formation target (in this embodiment, a paper surface is exemplified) to the image formation position. The supply unit 61 includes, for example, a roll body 611 (see FIG. 10) around which the medium A is wound, a roll drive motor (not shown), a roll drive wheel train (not shown), and the like. The roll drive motor is rotationally driven based on a command from the control unit 65, and the rotational force of the roll drive motor is transmitted to the roll body 611 via the roll drive wheel train. Thereby, the roll body 611 rotates and the paper surface wound around the roll body 611 is supplied to the downstream side (+ Y direction) in the Y direction (sub-scanning direction).
In the present embodiment, an example in which the paper surface wound around the roll body 611 is supplied is shown, but the present invention is not limited to this. For example, the medium A may be supplied by any supply method such as supplying the medium A such as a sheet of paper loaded on a tray or the like one by one with a roller or the like.

The transport unit 62 transports the medium A supplied from the supply unit 61 along the Y direction. The transport unit 62 includes a transport roller 621, a driven roller (not shown) that is disposed with the transport roller 621 and the medium A interposed therebetween, and a platen 622.
The conveyance roller 621 receives a driving force from a conveyance motor (not shown), and when the conveyance motor is driven by the control of the control unit 65, the conveyance roller 621 is rotated by the rotation force, and the medium A is moved between the conveyance roller 621 and the driven roller. It is transported along the Y direction while being sandwiched. A platen 622 that faces the carriage 63 is provided on the downstream side (+ Y side) in the Y direction of the transport roller 621. The platen 622 contacts the surface of the medium A that is conveyed in the sub-scanning direction (Y direction) opposite to the medium surface A1, and holds the medium A.

The carriage 63 includes a printing unit 66 that prints an image on the medium surface A1 of the medium A, and the spectroscopic measurement device 1 that performs spectroscopic measurement at a predetermined measurement position on the medium surface A1.
The carriage 63 is provided so as to be movable along a main scanning direction (X direction) intersecting the Y direction by a carriage moving unit 64.
Further, the carriage 63 is connected to the control unit 65 by a flexible circuit 631, and based on a command from the control unit 65, printing processing by the printing unit 66 (image formation processing on the media surface A 1) and spectral measurement by the spectroscopic measurement apparatus 1. Perform the measurement.
The detailed configuration of the carriage 63 will be described later.

The carriage moving unit 64 reciprocates the carriage 63 along the X direction based on a command from the control unit 65.
The carriage moving unit 64 includes, for example, a carriage guide shaft 641, a carriage motor 642, and a timing belt 643.
The carriage guide shaft 641 is disposed along the X direction, and both ends are fixed to the housing of the printer 6, for example. The carriage motor 642 drives the timing belt 643. The timing belt 643 is supported substantially in parallel with the carriage guide shaft 641 and a part of the carriage 63 is fixed. When the carriage motor 642 is driven based on a command from the control unit 65, the timing belt 643 travels forward and backward, and the carriage 63 fixed to the timing belt 643 is guided by the carriage guide shaft 641 and reciprocates.

Next, the printing unit 66 and the spectroscopic measurement apparatus 1 provided on the carriage 63 will be described.
The printing unit 66 is an image forming unit and is provided to face the medium A, and forms an image by individually ejecting a plurality of colors of ink onto the medium surface A1.
The printing unit 66 is detachably mounted with ink cartridges 661 corresponding to a plurality of colors of ink, and ink is supplied from each ink cartridge 661 to an ink tank (not shown) via a tube (not shown). . In addition, nozzles (not shown) for ejecting ink droplets are provided for the respective colors on the lower surface of the printing unit 66 (position facing the media surface A1). For example, piezo elements are disposed in these nozzles, and by driving the piezo elements, ink droplets supplied from the ink tank are ejected and land on the media surface A1 to form dots.

The spectrometer 1 has the same configuration as that of the first embodiment.
In the present embodiment, a plurality of color patches are printed on the media surface A1, and the spectroscopic measurement apparatus 1 executes spectroscopic measurement processing for each color patch. That is, every time a color patch is measured, the spectroscopic measurement apparatus 1 sets the distance of the gap G1 of the wavelength tunable interference filter 5 as a reference distance, detects the amount of change in parasitic capacitance, and then increases the gap G1 sequentially. Measure the amount of light of each target wavelength.
The spectroscopic measurement may be performed a plurality of times for the same color patch. In this case, for example, the average value of the measured values is stored in the storage unit 30 as the measured light amount.

As illustrated in FIG. 11, the control unit 65 includes an I / F 651, a unit control circuit 652, a memory 653, and a CPU 654.
The I / F 651 inputs print data input from the external device 70 to the CPU 654.
The unit control circuit 652 includes control circuits that respectively control the supply unit 61, the transport unit 62, the printing unit 66, the spectroscopic measurement device 1, and the carriage movement unit 64, and each unit is based on a command signal from the CPU 654. To control the operation. The control circuit of each unit may be provided separately from the control unit 65 and connected to the control unit 65.
The memory 653 stores various programs and various data for controlling the operation of the printer 6.

[Operational effects of the second embodiment]
According to the present embodiment, when performing spectroscopic measurement on a color patch, the amount of light having a target wavelength can be detected with high accuracy, so that color correction can be performed with high accuracy.
Further, when the spectroscopic measurement apparatus 1 performs measurement processing continuously as in the present embodiment, the parasitic capacitance generated in the wavelength tunable interference filter 5 may change during measurement due to power supply fluctuation or the like. In the present embodiment, the amount of change in parasitic capacitance is detected every time a series of driving processes for changing the dimension of the gap G1 from the dimension corresponding to the shortest wavelength among the target wavelengths to the dimension corresponding to the longest wavelength is performed. Therefore, for example, the distance of the gap G1 can be accurately adjusted to a value (target value) corresponding to each target wavelength as compared with the case where the amount of change in the parasitic capacitance is detected only when the power is turned on.

[Other Embodiments]
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 each of the above embodiments, the optical module 10 detects the electrostatic capacitance between the reflective films 54 and 55 by the gap detector 151 and performs feedback control. However, the present invention is not limited to this.
For example, the gap detector 151 may detect the electrostatic capacitance between the fixed electrode 561 and the movable electrode 562 and perform feedback control. In this case, the fixed electrode 561 and the movable electrode 562 constitute a pair of opposing members of the present invention. In this configuration, the capacitance detected by the gap detector 151 is corrected by the difference between the capacitance and the ideal value when the distance between the fixed electrode 561 and the movable electrode 562 is the reference distance.
Alternatively, the capacitance detection electrodes facing each other may be provided on the fixed substrate 51 and the movable substrate 52, and the capacitance between the capacitance detection electrodes may be detected by the gap detector 151 to perform feedback control.

In each said embodiment, although the distance maintenance part which maintains the distance of the gap G1 at a reference distance is comprised by the 1st pillar part 571 and the 2nd pillar part 572, it is not limited to this.
For example, the distance maintaining unit may be configured by a pillar provided on one of the fixed substrate 51 and the movable substrate 52. In this case, the height of the pillar may be set to a height dimension that combines the first pillar portion 571 and the second pillar portion 572.
Further, for example, the fixed electrode 561 and the movable electrode 562 may be configured to function as a distance maintaining unit. In this case, an insulating layer is provided on at least one of the fixed electrode 561 and the movable electrode 562, and the distance of the gap G1 becomes the reference distance when the fixed electrode 561 and the movable electrode 562 come into contact with each other through the insulating layer. To do.
In addition, the distance maintaining unit pushes the movable unit 521 from the side opposite to the fixed substrate 51 side by a driving force generated by, for example, a motor or the like to pull the size of the gap G1 to the reference distance. You may be comprised by the mechanism to maintain.

In each of the embodiments described above, the wavelength variable interference filter 5 includes the electrostatic actuator 56 that varies the gap dimension between the reflective films 54 and 55 by applying a voltage, but the present invention is not limited to this.
For example, a configuration may be used in which a first dielectric coil is disposed instead of the fixed electrode 561 and a dielectric actuator in which a second dielectric coil or a permanent magnet is disposed instead of the movable electrode 562.
Further, a piezoelectric actuator may be used instead of the electrostatic actuator 56. In this case, for example, the lower electrode layer, the piezoelectric film, and the upper electrode layer are stacked on the holding unit 522, and the voltage applied between the lower electrode layer and the upper electrode layer is varied as an input value, thereby expanding and contracting the piezoelectric film. Thus, the holding portion 522 can be bent.

In each of the above embodiments, the reference distance set when correcting the gap correlation data is set to the minimum distance of the gap G1, but is not limited thereto.
For example, the reference distance may be set to the maximum distance of the gap G1. In this case, the distance maintaining unit, for example, a mechanism that maintains the size of the gap G1 at the reference distance by pulling the movable unit 521 from the side opposite to the fixed substrate 51 side by a driving force generated by a motor or the like. Consists of. Then, after changing the distance of the gap G1 to the reference distance, the distance is sequentially reduced, and the amount of light of each target wavelength is measured.

In each of the above-described embodiments, in the spectroscopic measurement process, the correction unit 162 corrects the gap correlation data based on the difference between the second detection value and the ideal value, and the filter driving unit 152 detects the static value detected by the gap detector 151. The electric capacity is converted into the size of the gap G1 with reference to the corrected gap correlation data, but is not limited to this.
For example, the gap correlation data is not changed, and the difference is stored in the memory 161 or the like, and every time the filter driving unit 152 detects the capacitance by the gap detector 151, the detected capacitance is set. The difference may be read and added, and the added value may be converted to the size of the gap G1 with reference to the gap correlation data.

In each of the above embodiments, the drive control unit 163 outputs the dimension of the gap G1 as a target signal, and the filter drive unit 152 refers to the gap correlation data with respect to the capacitance detected by the gap detector 151. Although it converts into the dimension of G1 and performs feedback control compared with a target signal, it is not limited to this.
For example, the drive control unit 163 refers to relationship data indicating the relationship between the size of the gap G1 and the capacitance, converts the size of the gap G1 into capacitance, and outputs the target signal, and the filter drive unit 152 The electrostatic capacitance detected by the gap detector 151 may be compared with a target signal to perform feedback control. In this case, the correction unit 162 corrects the relationship data based on the difference between the second detection value and the ideal value, thereby correcting the target signal with the amount of change in parasitic capacitance. That is, the first detection value is corrected by correcting the target signal. Thereby, feedback control can be performed based on the corrected first detection value.

  In each of the above embodiments, the drive device that drives the variable wavelength interference filter 5 and sets the distance between the reflective films 54 and 55 to the target value is exemplified, but the present invention may be applied to other drive devices. Applicable. That is, the present invention can be widely applied to a drive device that sets the distance between a pair of opposing members to a target value. For example, the present invention can be applied to a mirror device that changes the angle of a mirror by electrostatic capacitance.

  DESCRIPTION OF SYMBOLS 1 ... Spectrometer, 5 ... Wavelength variable interference filter, 10 ... Optical module (drive device), 15 ... Voltage control part, 16 ... Microcomputer, 51 ... Fixed substrate (first substrate), 52 ... Movable substrate (second substrate) ), 53 ... Bonding film, 54 ... Fixed reflection film (first mirror), 55 ... Movable reflection film (second mirror), 56 ... Electrostatic actuator, 151 ... Gap detector (capacitance detection unit), 152 ... Filter drive 161, memory, 162, correction unit, 163, drive control unit, 511, electrode placement groove, 511A, groove bottom surface, 512, reflective film installation unit, 521, movable unit, 521A, movable surface, 522, holding unit, 525 ... Substrate outer periphery, 561 ... Fixed electrode, 562 ... Movable electrode, 571 ... First pillar part (protrusion part that is a part of the distance maintaining part), 571A ... Base end part, 571B ... Tip part, 572 ... Second Pila Parts (that is part protruding portion of the distance maintaining portion), G1, G2 ... gap.

Claims (6)

A pair of opposing members facing each other;
A capacitance detection unit for detecting a capacitance between the pair of opposing members;
A gap changing unit that changes a distance between the pair of opposing members based on an input signal;
A distance maintaining unit that maintains a distance between the pair of opposing members at a reference distance;
A feedback control unit that performs feedback control of the input signal based on a first detection value that is the capacitance detected by the capacitance detection unit;
The feedback control unit includes a second detection value that is the capacitance detected by the capacitance detection unit when a distance between the pair of opposing members becomes the reference distance, and the pair of opposing members. Performing the feedback control by correcting the first detection value based on a difference from an ideal value of the capacitance between the pair of opposing members when the distance between the reference members is the reference distance. A drive device characterized by the above. The drive device according to claim 1,
The reference distance is a minimum distance between the pair of opposing members that can be changed by the gap changing unit,
After the distance between the pair of opposing members is changed to the reference distance, the distance is sequentially increased. The drive device according to claim 1 or 2,
A storage unit that stores relationship data indicating a relationship between the capacitance between the pair of opposing members and a distance between the pair of opposing members;
The feedback control unit corrects the relational data based on a difference between the second detection value and the ideal value, and performs the feedback control based on the corrected relational data. . In the drive device according to any one of claims 1 to 3,
A first substrate provided with a first mirror, and a second substrate provided with a second mirror facing the first mirror and facing the first substrate,
The pair of opposing members are the first mirror and the second mirror. In the drive device according to any one of claims 1 to 3,
A first substrate on which one of the pair of opposing members is provided, and a second substrate on which the other of the pair of opposing members is provided and facing the first substrate,
The distance maintaining unit is provided on at least one of the first substrate and the second substrate, and when the distance between the pair of opposing members becomes the reference distance, the first substrate and the second substrate A driving device, characterized in that the driving device is a projecting portion that comes into contact with either one of the substrates. The driving device according to any one of claims 1 to 5,
An electronic apparatus comprising: a control unit that controls the driving device.