Invention Grant
- Patent Title: Camera with photometric function and optical element for camera
- Patent Title (中): 具有光度功能的相机和相机的光学元件
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Application No.: US11821387Application Date: 2007-06-22
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Publication No.: US07652710B2Publication Date: 2010-01-26
- Inventor: Masachika Watanabe , Yasuyuki Oyagi , Norihisa Moriya , Toru Iwane
- Applicant: Masachika Watanabe , Yasuyuki Oyagi , Norihisa Moriya , Toru Iwane
- Applicant Address: JP Tokyo JP Tokyo
- Assignee: Dai Nippon Printing Co., Ltd.,Nikon Corporation
- Current Assignee: Dai Nippon Printing Co., Ltd.,Nikon Corporation
- Current Assignee Address: JP Tokyo JP Tokyo
- Agency: Ladas & Parry LLP
- Priority: JP2006-181096 20060630
- Main IPC: H04N5/222
- IPC: H04N5/222

Abstract:
Optical system for guiding subject light incident through a photo-taking lens 20 toward a finder 100 through a prism 90 is prepared and a plate-like diffractive element 50 is provided on the optical path. Light from an LED 70 to be turned on when a focusing state is achieved is introduced into the plate-like diffractive element 50 via a light guide member 60, and “auxiliary light indicating a focusing state” to travel upward in the drawing from the plate-like diffractive element 50 is generated and synthesized with the subject light. The auxiliary light shall have a linear polarization property. The subject image and the focusing state indication can be visually recognized on the finder 100. Part of the light toward the finder 100 is branched through a mirror 110 and then guided toward photometric unit 140. Auxiliary light separating unit 130 for excluding auxiliary light based on the difference in polarization property is provided in front of the photometric unit 140.
Public/Granted literature
- US20080002047A1 Camera with photometric function and optical element for camera Public/Granted day:2008-01-03
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