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. 06, 2002
Filed:
May. 20, 1999
Masanori Iida, Katano, JP;
Hiroyuki Asakura, Osaka, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A wavelength tunable filter device has at least two optical fibers through which an optical signal is input or output; a wavelength selective element which the optical signal is input to and output from through a lens and which selects a wavelength; a mounting jig to which the wavelength selective element is fixedly secured; a rotating mechanism, having an ultrasonic motor and an encoder, for rotating the wavelength selective element; and a motor controller for controlling the ultrasonic motor for driving, wherein the mounting jig is rigidly mounted directly to a rotating shaft of the ultrasonic motor, and the amount of power that does not exceed the driving power necessary to cause the ultrasonic motor to start rotating from a stopped condition is intermittently applied to the motor controller.