Lens system with plastic lenses compensating for temperature changes
US4557567A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 5, 1983 |
| Grant date | Dec 10, 1985 |
| Priority date | — |
| Expiry date | Jan 5, 2003 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B15/145125
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
In a zoom lens system with plastic lenses, shifting of an image forming plane of the zoom lens caused by resultant deformation and optical characteristic changes due to temperature changes of plastic single lenses and of plastic lenses included in compound lenses in the zoom lens system is corrected by a compound lens of a plastic lens and a glass lens cemented together or by a compound lens of a plastic lens and a glass lens spaced apart from each other with a slight air gap between opposing surfaces thereof of substantially the same radius of curvature, the compound lens having a temperature change dependent shifting of image forming plane to correct that of other plastic lenses.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.