Invention Grant
- Patent Title: Projection lens, image projection apparatus and optical apparatus
- Patent Title (中): 投影镜头,图像投影装置和光学装置
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Application No.: US12147626Application Date: 2008-06-27
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Publication No.: US07830604B2Publication Date: 2010-11-09
- Inventor: Kazuhiro Inoko
- Applicant: Kazuhiro Inoko
- Applicant Address: JP Tokyo
- Assignee: Canon Kabushiki Kaisha
- Current Assignee: Canon Kabushiki Kaisha
- Current Assignee Address: JP Tokyo
- Agency: Canon U.S.A., Inc. IP Division
- Priority: JP2007-175065 20070703
- Main IPC: G02B15/14
- IPC: G02B15/14

Abstract:
The projection lens that projects a light flux from an object onto a projection surface. The projection lens includes a negative lens unit having a negative optical power, and a correction mechanism that tilts the negative lens unit with respect to an optical axis of the projection lens such that field tilt is generated in a direction opposite to a direction of field curvature generated at the projection surface. The projection lens reduces the generation of field curvature and its variation using a simple configuration.
Public/Granted literature
- US20090009878A1 PROJECTION LENS, IMAGE PROJECTION APPARATUS AND OPTICAL APPARATUS Public/Granted day:2009-01-08
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