Lens
US5013143A · kind A · utility
23Cited by
1References
3Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Dec 21, 1989 |
| Grant date | May 7, 1991 |
| Priority date | — |
| Expiry date | Dec 21, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B3/04
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A lens or lens system for use in reading optical data has as one component a pickup lens having finite or infinite conjugates. The pickup lens is biaspheric where the surfaces may have spherical, paraboloidal or general conic base curves and higher order correction terms up to 40th order when required. Various methods of making such a lens of plastics material are also disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.