Two-dimensional optical low-pass filter
US5504621A · kind A · utility
7Cited by
3References
7Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Aug 27, 1993 |
| Grant date | Apr 2, 1996 |
| Priority date | — |
| Expiry date | Aug 27, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B27/46
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A two-dimensional optical low-pass filter includes an optical phase grating having a plurality of unitary grating periods on only one side of a grating plane. Each of the unitary grating periods includes at least two phase retardation structures spaced from each other, thereby providing phase retardation across the grating plane. The two phase retardation structures invariably have at least one non-continuous phase retardation configuration substantially in all directions on the grating plane.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.