Holographic apparatus using incoherent light

US5081540A · kind A · utility

Assignee

• Etat Francais, Represente par le Ministre des Pos Tes, Destelecommunicati ons et de l'Space-Centre National d'Etudes des Telecommunications (C.N.E.T.) · FR

Inventors

• Eric Dufresne · Arlington, US
• Pierre Chavel · Los Angeles, US
• Gabriel Y. Sirat · Paris, FR

Key dates

• Filing date: Apr 20, 1990
• Grant date: Jan 14, 1992
• Expiry date: Apr 20, 2010

Classification

• Technology area (CPC G): Physics
• CPC primary: G03H1/0493
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

A holographic apparatus of the type comprising a conoscopic system including a birefringent crystal inserted between two polarizers, wherein the apparatus also includes an aperture angle limiter inserted on the path of the light rays and wherein one of the birefringent crystal and the aperture angle limiter is disposed off the optical axis of the apparatus.