Focus adjusting apparatus provided with a focus lens member formed of polymer gel substance having electro-reactive deformability
US4989958A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 2, 1988 |
| Grant date | Feb 5, 1991 |
| Priority date | — |
| Expiry date | Nov 2, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F1/29
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A focus adjusting apparatus comprises a focus lens device provided in an optical system. The focus lens device comprises a transparent container of a rectangular prism form, a lens member supported in the container and formed of poly(acrylic amide) gel as a polymer gel substance having electro-reactive deformability, and a pair of transparent electrodes, the container being filled with water-aceton mixture solution. The lens member is formed by two lens materials having different proportions of acrylic acid group. A voltage is applied to the transparent electrodes under control of an automatic focusing circuit to cause electric field in the container, whereby the lens member is deformed in a concentric spherical form to form a lens. When the application of the voltage is stopped, the lens member returns to the initial form. A focal distance of the lens member is changed according to degrees of such deformation of the lens member.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.