Diffraction apparatus with correcting grating and method of making
US4842353A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 11, 1985 |
| Grant date | Jun 27, 1989 |
| Priority date | — |
| Expiry date | Oct 11, 2005 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S359/90
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method of making a corrected plane holographic grating within one band of wavelengths, intended for use in a diffraction apparatus in which light emitted by an entry source (1) is collimated by a spherical mirror (2) to the grating (4), which reflects parallel pencils to another spherical mirror (7), a focusing mirror, is disclosed. An auxiliary holographic grating (25) is created by the interference on a spherical surface (15) of a parallel pencil of light produced by the spherical mirror (7) subsequent to reflection onto a plane mirror (12) and of a divergent pencil deriving from the center of the surface (15). The auxiliary grating, corrected by the interference on a plane surface (22) of a parallel pencil produced by the spherical mirror (2) and of another parallel pencil produced by the auxiliary grating (25) illuminated from the center of the spherical surface, is then recorded.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.