发明名称 Distance measuring apparatus of a camera
摘要 A distance measuring apparatus of a camera is capable of performing passive and active distance measurements. A pair of light-receiving optical systems for forming images of an object in focus on respective light-detecting elements are adapted to define symmetrical light-receiving optical paths, respectively. A pair of first light beams transmitted from infinity are symmetrically incident on the light-detecting elements at one ends thereof, respectively. A pair of second light beams transmitted from a limit position which defines a measurable shortest object distance in a passive distance measurement, are incident on the light-detecting elements at the other ends thereof, respectively. A light-emitting unit for emitting an auxiliary light beam toward an object has a light-emitting optical axis which is arranged in a plane including the light-receiving optical axes of the light-receiving optical systems so that it passes through the limit position in at least either of the light-receiving optical paths. The auxiliary light beam reflected by an object which is located at the shorter distance side of the limit position, can be detected by at least either of the light-detecting elements.
申请公布号 US4947202(A) 申请公布日期 1990.08.07
申请号 US19890375986 申请日期 1989.07.06
申请人 RICOH COMPANY, LTD. 发明人 KITAJIMA, TOMOYA;SUZUKI, AKIRA
分类号 G01C3/06;G01C3/00;G02B7/28;G02B7/30;G02B7/32;G02B7/34;G03B13/36 主分类号 G01C3/06
代理机构 代理人
主权项
地址