Patent · US Expired

Diffraction grating having high throughput efficiency

US7139128B2 · kind B2 · utility

8Cited by
12References
79Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 6, 2004
Grant dateNov 21, 2006
Priority date—
Expiry dateFeb 15, 2024

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02B5/1861
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A reflective diffraction grating having grooves and ridges and providing high throughput efficiency in the minus-first diffraction order. All but the zeroth diffraction order and the minus-first diffraction order may be prevented from existence by directing the radiation onto the grating at an appropriate angle. The radiation having a TM polarization is eliminated from the zeroth order by destructive interference by appropriate selection of a the groove width of the grating, and radiation having a TE polarization is eliminated from the zeroth order by destructive interference by depositing an overcoat of an appropriate thickness. A dielectric material may be deposited in the grooves.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.