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:
Feb. 13, 2001
Filed:
Jun. 25, 1999
Denso Corporation, Kariya, JP;
Abstract
A variable focus lens device having a temperature compensation function whose construction is simple and which can be inexpensively manufactured. The device has a lens member including a lens container having a transparent elastic film, a transparent sealing member forming an internal volume, and a transparent liquid filling the internal volume, a stack-type piezoelectric actuator for varying the focus of the lens member by deforming the transparent elastic film by fluctuating the pressure inside the internal volume, and a tank connected to the internal volume by narrow passages. The tank and the narrow passages absorb temperature fluctuation components of the transparent liquid, which varies due to thermal expansion and contraction. The tank and the passages thereby form a temperature compensator, that, because the passages are narrow, does not react to sudden oscillating pressure components caused by the stack-type piezoelectric actuator.