Optical system for diffusing light
US6259561A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 26, 1999 |
| Grant date | Jul 10, 2001 |
| Priority date | — |
| Expiry date | Mar 26, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B27/425
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An improved optical system is provided for diffusing light uniformly over a wide angle, including, a diffractive element for diffracting light received by the system in multiple diffraction orders, and a diffusing element which diffuses the diffracted light. The diffractive element provides diffracted light having an angular distribution of intensities over the diffraction orders which is correlated to the power spectrum of the diffusing element such that the system produces a predetermined intensity distribution of diffused light. The diffraction period of the diffractive element is selected such that the angular separation between the zeroeth and first diffraction orders is approximately one-half the angular extent of the full-width-at-half-maximum of the power spectrum of the diffusing element. The strengths of the diffraction orders are selected such that the combination of diffused light from each diffractive order provides uniformity in the intensity of the diffused light from the system.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.