The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 27, 1978
Filed:
Dec. 07, 1976
Naoyuki Uno, Urawa, JA;
Katsuhiko Miyata, Tsurugashima, JA;
Asahi Kogaku Kogyo Kabushiki Kaisha, Tokyo, JA;
Abstract
A light meter for a SLR camera implements both initial exposure time display and automatic exposure time control using a single light sensing element 8. The reflex mirror 3is formed as a beam splitter or half-mirror. When lowered, some of the viewfinder light passes through the mirror and is reflected onto the sensing face of the element 8 by the shutter curtains 9 or 10 to enable the time display function. When the mirror is raised and the lens diaphragm 2 reduced, the light is again reflected from the curtains and/or film surface 11 onto the sensing element face to enable the time control function. A hinged shield 13 may be provided to block light from entering the camera box 12 via the rangefinder lens 7 when the mirror 3 is raised, and dual sensing elements 8, 8' may be employed together with an additional reflecting mirror 15 and an angled or concave shield 13 ' to effect a uniform vertical light distribution sensitivity in both the display and control modes.