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:
Aug. 30, 1988
Filed:
Apr. 07, 1987
Saburo Sasaki, Tokyo, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
A lens driving device for driving a lens for use in adjusting a focus according to a distance therefrom to an object by a pulse motor, comprising; a lens driving section for driving the lens by the pulse motor, a distance measuring section for measuring the distance to the object and generating a distance information for focusing, and a generator for generating a pulse signal for driving the pulse motor, setting a pulse width of the pulse signal to a broad width at starting the pulse motor, changing the pulse width to a narrow width after starting, temporarily interrupting the generation of the pulse signal just before the lens reaches a predetermined stop position determined on the basis of the distance information for focusing generated by the distance measuring section and changing the pulse width to a broad width till the lens reaches the predetermined stop position.