Low noise optical system
US5002393A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 30, 1989 |
| Grant date | Mar 26, 1991 |
| Priority date | — |
| Expiry date | May 30, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01J3/1838
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A double spectrograph system is disclosed. An entrance slit receives and passes light to be analyzed. A first focusing diffraction grating receives that light. A second focusing diffraction grating receives light reflected by the first focusing diffraction grating. The first and second focusing diffraction gratings both have the characteristic of forming planar substantially anastigmatic spectra. Mounting means keeps the first and second gratings at positions symmetrical about an imaginary plane and with their respective focal planes substantially coincident with each other and the imaginary plane. An exit slit receives the light after it has been reflected by the first grating to the second grating and from the second grating to the exit slit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.