Thomson-csf

C&eacute;cile Joubert

Jean-Pierre Huignard

Brigitte Loiseaux

Jean-Claude Lehureau

Anne Delboulbe

Color display system, which includes an electrooptic modulation screen (LCD) and in which a chromatic modulator (RC) is provided between the multiple-wavelength light source (S, C) and the screen (LCD). This chromatic modulator modulates a wavelength or a restricted range of wavelengths of the source in order to adjust the saturation of the various primaries transmitted to the screen as well as to effect colorimetric balance. Applications include liquid-crystal color displays.

Illumination system for an electrooptic color display screen

A polarization splitter which includes a splitting medium lying between two transparent elements of defined indices. The splitting medium includes a periodic structure of layers of materials of different indices and having a period which is small compared with the wavelength of an incident beam so as to form a uniaxial birefringent medium of optical axis perpendicular to the plane of the periodic structure. The two transparent elements are made of a material of index approximately equal to the ordinary index (n ) of the periodic structure.

Polarization beam splitter

A holographic projection screen for large screen projection and back projection with a liquid crystal projector. The screen includes at least one layer made of a photosensitive material in which at least one index grating may be recorded by an interference of an optical recording wave with an optical object wave. The thickness of the layer is equal to or greater than n,&Lgr;,/2&pgr;, where n,is the average index of the photosensitive material, &Lgr; is the average spacing of the index grating and &lgr; is the recording wavelength.

Holographic projection screen and method of production

A compact illumination device intended especially for illuminating an active matrix in a monochromatic or trichromatic display device. This device includes a source and collimating device in order to deliver a lighting direction from the source along a direction (Dy) and two optical components (M,) and (M,) which anamorphose the lighting in a direction parallel to the direction (Dy) and in a direction (Dz) perpendicular to the direction (Dy), respectively. These components may typically be of the holographic grating type operating in transmission or in reflection.

Growing community of inventors

Paris, France

Cécile Joubert

Growing community of inventors

Paris, France

C&eacute;cile Joubert

Cécile Joubert