Large aperture imaging optical systems
US8169717B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jun 7, 2010 |
| Grant date | May 1, 2012 |
| Priority date | — |
| Expiry date | Oct 16, 2030 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B13/20
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Large aperture optical systems that are extremely well corrected over a large flat field and over a large spectral range are disclosed. Breathing and aberration variation during focusing are optionally controlled by moving at least two groups of lens elements independently. Aberration correction in general is aided by allowing the working distance to become short relative to the format diagonal. Field curvature is largely corrected by a steeply curved concave surface relatively close to the image plane. This allows the main collective elements to be made of low-index anomalous dispersion materials in order to correct secondary spectrum. In wide-angle example embodiments, distortion may be controlled with an aspheric surface near the front of the lens.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.