# US 2022/0035162 A1 · Virtual image display device and optical unit > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2022/0035162 A1 - Document ID: US20220035162A1 - Status: Published application - Kind: A1 - Application number: 17/388,436 - Filed: 2021-07-29 - Published: 2022-02-03 - Earliest claimed: 2020-07-30 - Assignees: Seiko Epson Corporation - Applicants: Seiko Epson Corporation - Inventors: Daiki MATSUMOTO - Web page: https://patentgrep.com/patent/US20220035162A1 ## CPC - G02B 27/0172: {characterised by optical features} - G02B 5/26: Reflecting filters (G02B5/28 takes precedence) - G02B 17/08: Catadioptric systems {(used in non-imaging applications G02B19/00)} - G02B 2027/0178: {Eyeglass type (eyeglass details G02C)} - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS ## Abstract An image light generation device generating image light, a semi-transmissive tilted mirror reflecting the image light from the image light generation device, and a concave semi-transmissive mirror reflecting, toward the semi-transmissive tilted mirror, the image light reflected by the semi-transmissive tilted mirror to form an exit pupil are provided, and the concave semi-transmissive mirror includes a partial reflective film having different reflectance according to wavelength, the semi-transmissive tilted mirror reflects the image light toward the partial reflective film. ## Claims ### Claim 1 A virtual image display device comprising: an image light generation device generating image light; a first mirror reflecting the image light from the image light generation device; and a second mirror having a concave shape and reflecting, toward the first mirror, the image light reflected by the first mirror, wherein the second mirror includes a first reflective film on which the image light reflected by the first mirror is incident, the first reflective film has different reflectance according to wavelength. ### Claim 2 (depends on 1) The virtual image display device according to claim 1, wherein in a visible range, the first reflective film having a property that reflectance with respect to a first wavelength region corresponding to the image light is higher than reflectance with respect to a second wavelength region excluding the first wavelength region. ### Claim 3 (depends on 2) The virtual image display device according to claim 2, wherein the first reflective film substantially transmits light in the second wavelength region. ### Claim 4 (depends on 2) The virtual image display device according to claim 2, wherein the first reflective film transmits a part of light in the second wavelength region. ### Claim 5 (depends on 1) The virtual image display device according to claim 1, wherein the second wavelength region includes specific wavelength related to alarms, the first wavelength region is shifted from the second wavelength. ### Claim 6 (depends on 5) The virtual image display device according to claim 5, wherein the first wavelength region is shifted from the second wavelength region by a shift amount of 30 nm or smaller. ### Claim 7 (depends on 1) The virtual image display device according to claim 1, wherein the second mirror includes a supporting member including a first surface and a second surface opposing to the first surface, the first reflective film is provided along the first surface of the support member, an anti-reflective film is provided along the second surface of the support member, the anti-reflective film reduces reflection of the image light through the first reflective film. ### Claim 8 (depends on 1) The virtual image display device according to claim 1, wherein the second mirror reflects the image light toward the first mirror to form an exit pupil. ### Claim 9 (depends on 1) The virtual image display device according to claim 1, further comprising a shade spaced apart from the second mirror, wherein the second mirror is disposed between the first mirror and the shade. ### Claim 10 (depends on 9) The virtual image display device according to claim 9, wherein the shade covers the first reflective film. ### Claim 11 (depends on 9) The virtual image display device according to claim 9, wherein the shade includes a second reflective film having different reflectance according to wavelength. ### Claim 12 (depends on 1) The virtual image display device according to claim 1, wherein the second mirror has a thickness of 2 mm or smaller. ### Claim 13 (depends on 1) The virtual image display device according to claim 1, wherein an emission light axis extending from the first mirror toward the second mirror is inclined to downward direction with respect to a horizontal axis. ### Claim 14 (depends on 1) The virtual image display device according to claim 1, further comprising a third mirror reflecting, to an intersection direction, the image light from the image light generation device. ### Claim 15 (depends on 1) The virtual image display device according to claim 1, further comprising a projection optical system being disposed between the image light generation device and the first mirror, the projection optical system forming an intermediate image. ### Claim 16 (depends on 1) The virtual image display device according to claim 1, wherein the image light is entered to the second mirror without forming an intermediate image. ### Claim 17 An optical unit comprising: a first mirror reflecting an image light; and a second mirror having a concave shape and reflecting, toward the first mirror, the image light reflected by the first mirror, wherein the second mirror includes a reflective film on which the image light reflected by the first mirror is incident, the first reflective film has different reflectance according to wavelength.