# US 11,442,328 B2 · Optical device and electronic apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,442,328 B2 - Document ID: US11442328B2 - Status: Granted - Kind: B2 - Application number: 16/583,397 - Filed: 2019-09-26 - Published: 2020-04-02 - Granted: 2022-09-13 - Earliest claimed: 2018-09-27 - Assignees: Seiko Epson Corporation - Applicants: Seiko Epson Corporation - Inventors: Yasushi Matsuno; Teruyuki Nishimura - Web page: https://patentgrep.com/patent/US11442328B2 ## CPC - 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)} - G02F 1/21: by interference - G01J 3/0262: {Constructional arrangements for removing stray light} - G01J 3/0294: {Multi-channel spectroscopy} - G01J 3/26: using multiple reflection, e.g. Fabry-Perot interferometer, variable interference filters - G01N 21/00: Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light (G01N3/00 - G01N19/00 take precedence) - G02B 5/285: {comprising deposited thin solid films (G02B5/281 - G02B5/289 take precedence; multilayered film filters for fibre optic multiplexing G02B6/29361)} - G02F 1/213: {Fabry-Perot type} - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS - G02F: OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS - G01J: MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY (light sources F21, H01J, H01K, H05B; investigating properties of materials by optical means G01N) - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) ## Abstract Provided is an optical device including a first wavelength variable interference filter in which a first reflective film and a second reflective film face each other with a first gap in between; a second wavelength variable interference filter in which a third reflective film and a fourth reflective film face each other with a second gap in between; and a first substrate having a transmissive property, which has a first surface and a second surface which is opposite in direction to the first surface, in which the second reflective film is provided on the first surface of the first substrate, and in which the third reflective film is provided on the second surface of the first substrate. ## Claims ### Claim 1 An optical device comprising: a first substrate having a transmissive property, the first substrate having a first surface and a second surface outwardly opposite to each other along a first direction; a first wavelength variable interference filter including: a first reflective film, an entirety of the first reflective film being provided on the first surface of the first substrate; and a second reflective film, an entirety of the second reflective film being overlapped and aligned with the first reflective film along the first direction, a periphery area of the second reflective film being stacked on a periphery area of the first reflective film via either a first electrode or a second electrode, a center area of the second reflective film being located above a center area of the first reflective film via a first air gap along the first direction; and a second wavelength variable interference filter including: a third reflective film, an entirety of the third reflective film being provided on the second surface of the first substrate; and a fourth reflective film, an entirety of the fourth reflective film being overlapped and aligned with the third reflective film along the first direction, a periphery area of the fourth reflective films being stacked on a periphery area of the third reflective film via either a third electrode or a fourth electrode, a center area of the fourth reflective film being located below a center area of the third reflective film via a second air gap along the first direction. ### Claim 2 (depends on 1) The optical device according to claim 1, wherein the first electrode of the first wavelength variable interference filter is provided on the first reflective film, the second electrode of the first wavelength variable interference filter is provided on the second reflective film, the first electrode and the second electrode face each other with the first air gap, the third electrode of the second wavelength variable interference filter is provided on the third reflective film, the fourth electrode of the second wavelength variable interference filter is provided on the fourth reflective film, the third electrode and the fourth electrode face each other with the second air gap, and the first substrate includes a first through-hole that passes through the first substrate from the first surface to the second surface, and one of the first electrode and the second electrode conducts electricity to one of the third electrode and the fourth electrode through the first through-hole. ### Claim 3 (depends on 1) The optical device according to claim 1, wherein the first wavelength variable interference filter is configured to change a dimension of the first air gap and thus to make a first transmission wavelength, which is a wavelength of light that is caused to pass through the first wavelength variable interference filter, to be changed in a range from a first wavelength to a second wavelength that is longer in wavelength than the first wavelength, and the second wavelength variable interference filter is configured to change a dimension of the second air gap and thus to make a second transmission wavelength, which is a wavelength of light that is caused to pass through the second wavelength variable interference filter, to be changed in a range from a third wavelength that is longer in wavelength than the first wavelength and is shorter in wavelength than the second wavelength to a fourth wavelength that is longer in wavelength than the second wavelength. ### Claim 4 (depends on 3) The optical device according to claim 3, wherein a distance between the first reflective film and the third reflective film is 300 times or more a center wavelength in a wavelength region from the first wavelength to the fourth wavelength. ### Claim 5 (depends on 3) The optical device according to claim 3, wherein a distance between the first reflective film and the third reflective film is 30000 times or less a center wavelength in a wavelength region from the first wavelength to the fourth wavelength. ### Claim 6 (depends on 1) The optical device according to claim 1, wherein a distance between the first reflective film and the third reflective film is longer than a distance between the first reflective film and the second reflective film and is longer than a distance between the third reflective film and the fourth reflective film. ### Claim 7 (depends on 1) An electronic apparatus comprising: an optical device according to claim 1; and a control unit that controls the optical device.