United States Patent [19] [li] Patent Number: 4,483,602
Aoki et al. [45] Date of Patent: Nov. 20, 1984
[54] APPARATUS FOR DETECTING A
FOCUSING CONDITION OF AN OBJECTIVE
LENS
[75] Inventors: Masahiro Aoki, Fussa; Kenichi
Oinoue, Tokyo; Masatoshi Ida; Asao
Hayashi, both of Hachioji, all of
Japan
[73] Assignee: Olympus Optical Co., Ltd., Japan
[21] Appl. No.: 362,993
[22] Filed: Mar. 29, 1982
[30] Foreign Application Priority Data
Mar. 28, 1981 [JP] Japan 56-46086
[51] Int. C1.3 G03B 7/08; G03B 17/20
[52] U.S. CI 354/402; 354/289.1
[58] Field of Search 354/25 R, 25 A, 25 P,
354/25 N, 31, 31 F, 53-55, 60 L, 198-201, 288, 289, 402-404, 289.1, 219
[56] References Cited
U.S. PATENT DOCUMENTS
3,354,803 11/1967 Winkler et al 354/289 X
4,047,187 9/1977 Mashimo - 354/25
4,075,640 2/1978 Ueda et al 354/31
4,219,267 8/1980 Suzuki et al 354/289
4,246,476 1/1981 Stauffer 354/25 X
4,279,484 7/1981 Kimura 354/25 P
4,297,014 10/1981 Nakamura et al. 354/25
4,305,657 12/1981 Masunaga et al 354/25 X
Primary Examiner—William B. Perkey
Attorney, Agent, or Firm—Parkhurst & Oliff
[57] ABSTRACT
In a single-lens reflex camera having an objective lens, a focusing screen and a view finder, a photodetector array is arranged to receive a central part of an object image formed by the objective lens and a focusing condition of the objective lens is detected by calculating an evaluation function from image signals supplied from the photodetectors. A presetting dial for selecting given photodetectors whose image signals are used for detecting the focusing condition is provided at such a position that a part of the dial is exposed to the outside through an opening formed in a rear wall of a camera body at a position underneath a film winding lever. A light emitting diode array is provided on the focusing screen so as to be seen by a user through the view finder. Only desired light emitting diodes are lighted on under the control of a signal supplied by the dial to indicate the region of the photodetector array which is used for detecting the focusing condition.
19 Claims, 10 Drawing Figures
