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. 29, 2009
Filed:
Mar. 26, 2007
Makoto Akiba, Saitama, JP;
Hideo Yoshida, Saitama, JP;
Makoto Akiba, Saitama, JP;
Hideo Yoshida, Saitama, JP;
Fujinon Corporation, Saitama-Shi, JP;
Abstract
A drive controller is provided and controls the supply of driving pulses in such a way as to make an extension speed and a contraction speed along a direction of a piezoelectric element differ to cause the piezoelectric element to extend and contract, so as to move a lens, the drive controller including an AF evaluation value-measuring device for measuring an AF evaluation value in a driving direction of the lens, a return pulse number-calculating device for calculating a maximum value-presuming position so as to calculate a return pulse number, a reverse movement-control device for returning the lens in a reverse direction, a threshold calculating device for calculating an evaluation value threshold, a measurement and determination means for remeasuring the AF evaluation value and determining whether or not an AF re-evaluation value is equal to or larger than the evaluation value threshold, and an AF evaluation value remeasuring device for remeasuring an AF evaluation value in the reverse direction of the lens.