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:
Mar. 13, 1990
Filed:
Dec. 23, 1988
Kosaku Sawabe, Ichikawa, JP;
Takashi Hongoh, Kawasaki, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
A distance measuring device for an automatic focusing camera which is automatically focused on an object in accordance with information data of distance to the object from the camera. The information data is obtained by irradiating a light emitted from a light emitting element to the object and receiving the light reflected from the object by an optical sensor. The optical sensor detects an incident point of the reflection light. The device comprises: a first light emitting element; an optical sensor; a second light emitting element; a light emission control circuit for controlling sequence of light emission from the first and second light emitting elements; a distance calculation circuit for calculating the information data of distance on the basis of an output from the optical sensor; a discrimination circuit for discriminating the information data; and a finder having an area mark for defining a field range. A first area in the finder defines a range of measurable distance by using only the first light emitting element. A second area defines a range of measurable distance by using only the second light emitting element. The longest distance side of the first area and the shortest distance side of the second area are overlapped each other in the finder.