Optical soft aperture and use thereof
US6008941A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 14, 1997 |
| Grant date | Dec 28, 1999 |
| Priority date | — |
| Expiry date | Apr 14, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S359/90
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A soft aperture allows gradual attenuation of a light beam dependent upon its location away from the center of a diffractive optical element. Such an optical element may be provided by decreasing a number of phase levels, increasing a number of phase levels, increasing a density of metal patches or diffractive gratings, or decreasing a blaze height and/or duty cycle, all radially from the center. Alternatively, the soft aperture may be defined by a photolithographic process. Such a soft aperture is particularly useful in aiding circularizing of an elliptical light beam. The soft aperture may be used alone or integrated with other optical elements.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.