Invention Grant
- Patent Title: Projective optical system and image projection device including a shielding unit
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Application No.: US14337522Application Date: 2014-07-22
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Publication No.: US10175568B2Publication Date: 2019-01-08
- Inventor: Hibiki Tatsuno
- Applicant: Hibiki Tatsuno
- Applicant Address: JP Tokyo
- Assignee: RICOH COMPANY, LTD.
- Current Assignee: RICOH COMPANY, LTD.
- Current Assignee Address: JP Tokyo
- Agency: Oblon, McClelland, Maier & Neustadt, L.L.P.
- Priority: JP2013-156190 20130726
- Main IPC: G03B21/28
- IPC: G03B21/28 ; G02B17/08 ; G03B21/14

Abstract:
A projective optical system comprises: a lens optical system including lenses; and a transmissive optical element having an anamorphic surface and being provided in an optical path between the lens optical system and a projected surface, wherein the transmissive optical element has a curvature with respect to a direction corresponding to a long side of a display screen of the image display element, and on a cross-sectional surface being perpendicular to the long side of the display screen, and with respect to light being emitted from the lens optical system and being incident to the transmissive optical element, a light intensity of a first light flux being incident to the transmissive optical element at a first incident angle is lower than a light intensity of a second light flux being incident to the transmissive optical element at a second incident angle being larger than the first incident angle.
Public/Granted literature
- US20150029474A1 PROJECTIVE OPTICAL SYSTEM AND IMAGE PROJECTION DEVICE Public/Granted day:2015-01-29
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