Imaging lens assembly
US11287601B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Feb 7, 2018 |
| Grant date | Mar 29, 2022 |
| Priority date | — |
| Expiry date | Sep 24, 2038 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B13/0055
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A multi-element imaging lens can be formed from five plastic elements, and an optional null-power or relatively low power sixth plastic element. The lens can use selected plastic materials to reduce a thermal focal shift. In the lens, negative refractive power elements can be formed from plastic materials having a relatively large negative refractive index variation with temperature, abbreviated as dn/dT, while positive refractive power elements can be formed from plastic materials having a relatively small negative dn/dT. Reducing the thermal focal shift, as disclosed, can eliminate the need for an auto-focusing device, such as a voice coil. Reducing the thermal focal shift, as disclosed, can also eliminate the need to use one or more glass elements to further reduce thermal focal shift, which can reduce cost for the lens.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.