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:
Sep. 15, 1992
Filed:
Feb. 28, 1991
Minoru Takahashi, Saitama, JP;
Mitsuo Yokota, Saitama, JP;
Fuji Photo Film Co., Ltd., Kanagawa, JP;
Abstract
A lens driving apparatus is provided with an encoder for detecting the position of a taking lens system. The encoder has a contact array including a main contact corresponding to a predetermined focal length position of a taking lens system and a sub-contact which is spaced slightly from the main contact. When a focal length changeover switch is operated to set the taking lens system in the desired focal length position, a motor is driven at a high speed until the sub-contact is detected and thereafter is driven at a low speed until the main contact is detected. So as to stop the taking lens system at the focal length position always after moving in one direction, when the taking lens system is to move in the other direction for changing over from a first to a second focal length position, the motor is driven at a high speed to move the taking lens system in the other direction until the encoder switches off the sub-contact corresponding to the second focal length position after detecting that sub-contact, and then the motor is driven at a low speed to move the taking lens system in the one direction until the associated main contact is detected. The taking lens system may be stopped when an end of a main contact is detected, and is moved into the predetermined focal length position that corresponds to the opposite end of the main contact when the shutter release button is operated.