Optical module, electronic apparatus, and spectroscopic camera

• US 9,297,997 B2
• Filed: 02/04/2014
• Issued: 03/29/2016
• Est. Priority Date: 02/05/2013
• Status: Active Grant

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Sano, Akira
• Primary Examiner(s): Lyons, Michael A
• Assistant Examiner(s): SMITH, MAURICE C
• Application Number:
  US14/171,866
• Publication Number:
  US 20140218586A1
• Time in Patent Office: 784 Days
• US Class Current: 1/1
• CPC Class Codes: G01J 3/26 using multiple reflection, e.g. Fabry-Perot interferometer, variable interference filters
• CPC Class Codes: G01J 3/51 using colour filters
• CPC Class Codes: G02B 26/001 based on interference in an adjustable optical cavity interference filters G02B5/28; devices or arrangements using multiple reflections in spectrometry or monochromators G01J3/26
• CPC Class Codes: G02B 26/0841 the reflecting element being moved or deformed by electrostatic means
• CPC Class Codes: G02B 6/29358 Multiple beam interferometer external to a light guide, e.g. Fabry-Pérot, etalon, VIPA plate, OTDL plate, continuous interferometer, parallel plate resonator G02B6/29347, G02B6/29349, G02B6/2935, G02B6/29361 take precedence; resonator evanescently coupled to light guide G02B6/29335

Abstract

An optical module includes a fixed reflection film, a movable reflection film, a first driver having a plurality of sub-drivers that can be driven independently of each other via voltage application in a plan view, a second driver that changes the dimension of a gap between the fixed reflection film and the movable reflection film, and a voltage controller that applies first drive voltages to the sub-drivers and applies a second drive voltage to the second driver, and the voltage controller applies a first drive voltage set for each of the sub-drivers in accordance with parallelism between the fixed reflection film and the movable reflection film at the time when the dimension of the gap is changed.

Claims

1. An optical module comprising:

a first reflection film that reflects part of incident light and transmits part thereof;

a second reflection film that faces the first reflection film, reflects part of incident light, and transmits part thereof;

a first driver provided in a region outside an optical interference area formed by the first reflection film and the second reflection film in a plan view, the first driver having a plurality of sub-drivers that are driven independently of each other via voltage application;

a second driver that changes a dimension of a gap between the first reflection film and the second reflection film; and

a voltage controller that applies first drive voltages to the sub-drivers and applies a second drive voltage to the second driver,

wherein the voltage controller applies a first drive voltage set for each of the sub-drivers in accordance with parallelism between the first reflection film and the second reflection film at a time when the dimension of the gap is changed.

2. The optical module according to claim 1, further comprising:

a gap detector that detects the dimension of the gap,

wherein the voltage controller applies the first drive voltages to the first driver to change the dimension of the gap by a predetermined amount and then applies a feedback voltage according to a size of gap detected with the gap detector to the second driver.

3. The optical module according to claim 2,

wherein the gap detector detects the dimension of the gap by detecting a capacitance between the first reflection film and the second reflection film.

4. The optical module according to claim 1,

wherein the first driver has three or more sub-drivers, and

the voltage controller applies the first drive voltage having either of two types of voltage waveforms to each of the sub-drivers.

5. The optical module according to claim 4,

wherein one of the first drive voltages having two types of voltage waveforms has a reference voltage waveform.

6. The optical module according to claim 1,

wherein the first driver has three or more sub-drivers,

the voltage controller applies the first drive voltage having either of three types of voltage waveforms to each of the sub-drivers, and

one of the first drive voltages having three types of voltage waveforms has a reference voltage waveform.

7. The optical module according to claim 1,

wherein each of the first driver and the second driver is an electrostatic actuator.

8. The optical module according to claim 1,

wherein the first driver controls parallelism between the first reflection film and the second reflection film, and the second driver changes the dimension of the gap.

9. The optical module according to claim 1,

wherein the first driver is disposed in a region outside the second driver.

10. The optical module according to claim 1,

wherein the plurality of sub-drivers of the first driver are disposed in an arcuate form along a circumference of an imaginary circle around a center of the first reflection film and a center of the second reflection film at equal angular intervals along the circumference of the imaginary circle in the plan view.

11. An electronic apparatus comprising:

an optical module; and

a control unit that controls the optical module,

the optical module including;

a first reflection film that reflects part of incident light and transmits part thereof,

a second reflection film that faces the first reflection film via a gap, reflects part of incident light, and transmits part thereof,

a first driver provided in a region outside an optical interference area formed by the first reflection film and the second reflection film in a plan view, the first driver having a plurality of sub-drivers that can be driven independently of each other via voltage application,

a second driver that changes a dimension of the gap between the first reflection film and the second reflection film, and

a voltage controller that applies first drive voltages to the sub-drivers and applies a second drive voltage to the second driver,

wherein the voltage controller applies a first drive voltage set for each of the sub-drivers in accordance with parallelism between the first reflection film and the second reflection film at the time when the second driver changes dimension of the gap.

12. A spectroscopic camera comprising:

an optical module; and

a control unit that controls the optical module,

the optical module including;

a first reflection film that reflects part of incident light and transmits part thereof,

a second reflection film that faces the first reflection film via a gap, reflects part of incident light, and transmits part thereof,

a first driver provided in a region outside an optical interference area formed by the first reflection film and the second reflection film in a plan view, the first driver having a plurality of sub-drivers that can be driven independently of each other via voltage application,

a second driver that changes a dimension of the gap between the first reflection film and the second reflection film,

a voltage controller that applies first drive voltages to the sub-drivers and applies a second drive voltage to the second driver, and

an imaging section that receives light of a wavelength selected based on interference of light that enters the gap between the first reflection film and the second reflection film to capture a spectroscopic image,

wherein the voltage controller applies a first drive voltage set for each of the sub-drivers in accordance with parallelism between the first reflection film and the second reflection film at the time when the second driver changes dimension of the gap.