Invention Grant
- Patent Title: Lens for projection, and image display device
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Application No.: US14509125Application Date: 2014-10-08
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Publication No.: US09864175B2Publication Date: 2018-01-09
- Inventor: Takashi Kubota
- Applicant: Takashi Kubota
- 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: JP2013-237422 20131115
- Main IPC: G02B13/16
- IPC: G02B13/16 ; G02B13/18 ; G02B13/04

Abstract:
A lens for projection which is used in an image display device which includes an image display element and projects and displays an image displayed on an image display surface of the image display element as a projection image on a projected surface in an enlarged manner, the lens for projection including in order from an enlargement side to a reduction side, a first lens group which is constituted of at least eight lenses and has a positive refractive power; an aperture; and a second lens group which is constituted of less than or equal to four lenses and has a positive refractive power, wherein the first lens group includes one or more aspherical lenses, and the one or at least one aspherical lens included in the first lens group has a largest thickness at a most peripheral portion of the lens.
Public/Granted literature
- US20150138649A1 LENS FOR PROJECTION, AND IMAGE DISPLAY DEVICE Public/Granted day:2015-05-21
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