Patent · US Expired

Side lobe suppression in holograms using pre-exposure

US4687720A · kind A · utility

25Cited by
7References
13Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 21, 1984
Grant dateAug 18, 1987
Priority date—
Expiry dateDec 21, 2004

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03H1/18
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A holographic recording medium is treated to eliminate side lobes. The method involves exposing opposed surfaces of the medium with filtered incoherent light either before or after a holographic exposure with coherent light. The incoherent exposure produces controlled desensitization of the medium, resulting in a sensitivity profile which increases continuously to a maximum near the center of the layer. A hologram recorded in the layer has a refractive index modulation which is high in the center of the layer and which decreases toward the surfaces of the layer.

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