Abstract: A filter, having a first filter material and second filter material, the first and second filter materials having different light attenuation properties and being in mutual contact along an interface surface, a cross-section of which has a curved line. Additionally, a method for preparing a filter, by: combining a first surface and an element to form a moulding cavity, delimited by the surface and by a moulding surface of the element; inserting a first material in liquid state; allowing the first material to solidify; removing the element to form a second moulding cavity, delimited by a second part of the surface and by the solidified first material; and inserting a second material in the second moulding cavity.

Abstract: A curved back-projection screen having an angle of curvature greater than 180°, such as a wrap-around cylindrical or dome screen. The screen includes a first layer and a second synthetic resin diffusing layer on the first layer, the second synthetic resin diffusing layer containing a light absorbing material and light diffusing particles embedded in a resin material, with the second synthetic resin diffusing layer having a value of the product of the absorption coefficient and thickness of between 0.1 and 2. The second synthetic resin diffusing layer can be applied by spraying.

Abstract: A curved back-projection screen having an angle of curvature greater than 180° is described such as a wrap-around cylindrical or dome screen. The screen includes a first layer and a second synthetic resin diffusing layer on the first layer, the second synthetic resin diffusing layer containing a light absorbing material and light diffusing particles embedded in a resin material, with the second synthetic resin diffusing layer having a value of the product of the absorption coefficient and thickness of between 0.1 and 2. The second synthetic resin diffusing layer can be applied by spraying.

Abstract: A DLP optical structure and corresponding method of controlling it are described including an optical integrator system having an optical integrator, a relay lens system, a TIR prism assembly, a digital imager, and a projection lens, said optical structure being adapted to accept a polarized light beam, said DLP optical structure comprising: at least one retarder positioned after said optical integrator for controlling the polarization state throughout said DLP optical structure, and achieving the desired polarization state after said projection lens; wherein said desired polarization state is substantially linear or circular. A DLP optical structure is also described including an optical integrator, a relay lens system, a TIR prism assembly, a digital imager and a projection lens, wherein the integrator is a fly-eye integrator for maintaining an input polarization of a light beam, and wherein said input polarization is linear or circular.

Abstract: A patterned retarder is described that may be used with a laser source array to obtain a combined beam suitable for laser image projection (e.g., three-dimensional laser image projection using orthogonal polarization states and/or orthogonal color spaces). An effect of the retarder on a polarization state of an incident beam may be dependent on the location of the retarder upon which the beam is incident. In one example, a method of producing a laser beam from a plurality of component laser beams includes directing the plurality of component laser beams onto corresponding regions of such a patterned retarder having a plurality of pattern elements.

Abstract: A filter, having a first filter material and second filter material, the first and second filter materials having different light attenuation properties and being in mutual contact along an interface surface, a cross-section of which has a curved line. Additionally, a method for preparing a filter, by: combining a first surface and an element to form a moulding cavity, delimited by the surface and by a moulding surface of the element; inserting a first material in liquid state; allowing the first material to solidify; removing the element to form a second moulding cavity, delimited by a second part of the surface and by the solidified first material; and inserting a second material in the second moulding cavity.

Abstract: The present invention relates in part to a print method for an arbitrary grey scale image on a transparent substrate such as glass. The present invention makes use of a printer that can print in continuous grey tones. The printed material should be transparent and resistant to the light which passes through it in a projection system. The present invention also provides a continuous grey scale filter made by a printing techniques using liquid inks or toners. Such a continuous grey scale filter can be used for blending multiple images in a multichannel projector system. The present invention also provides a multichannel projector system using the continuous grey scale filter.

Abstract: The invention pertains to a projector comprising an optical engine, a projection lens, a means for light deviation, and an afocal lens system, wherein the projector has a total throw ratio between 0.7 and 0.8. Such a projector can be used to build a very compact and cost-effective back-projection system. The invention also pertains to a projection assembly comprising such a projector, followed by a means for light gradation and a front-surface mirror. The invention also pertains to a display system comprising at least one such projection and a display screen.

Abstract: The present invention relates in part to a print method for an arbitrary grey scale image on a transparent substrate such as glass. The present invention makes use of a printer that can print in continuous grey tones. The printed material should be transparent and resistant to the light which passes through it in a projection system. The present invention also provides a continuous grey scale filter made by a printing techniques using liquid inks or toners. Such a continuous grey scale filter can be used for blending multiple images in a multichannel projector system. The present invention also provides a multichannel projector system using the continuous grey scale filter.

Abstract: A DLP optical structure and corresponding method of controlling it are described including an optical integrator system having an optical integrator, a relay lens system, a TIR prism assembly, a digital imager, and a projection lens, said optical structure being adapted to accept a polarized light beam, said DLP optical structure comprising: at least one retarder positioned after said optical integrator for controlling the polarization state throughout said DLP optical structure, and achieving the desired polarization state after said projection lens; wherein said desired polarization state is substantially linear or circular. A DLP optical structure is also described including an optical integrator, a relay lens system, a TIR prism assembly, a digital imager and a projection lens, wherein the integrator is a fly-eye integrator for maintaining an input polarization of a light beam, and wherein said input polarization is linear or circular.

Abstract: A patterned retarder is described that may be used with a laser source array to obtain a combined beam suitable for three-dimensional laser image projection using orthogonal polarization states and/or orthogonal color spaces.

Abstract: A curved back-projection screen having an angle of curvature greater than 180° is described such as a wrap-around cylindrical or dome screen. The screen includes a first layer and a second synthetic resin diffusing layer on the first layer, the second synthetic resin diffusing layer containing a light absorbing material and light diffusing particles embedded in a resin material, with the second synthetic resin diffusing layer having a value of the product of the absorption coefficient and thickness of between 0.1 and 2. The second synthetic resin diffusing layer can be applied by spraying.

Abstract: In one aspect, the present invention relates to a stereoscopic projection system including a projection device with at least one filter which filters a parameter of the light in a color selective manner. The at least one filter which filters a parameter of the light in a color selective manner has a spectral characteristic for transmitting light in a first wavelength band or set of wavelength bands and for reflecting light in a second wavelength band or set of wavelength bands. The projection device includes a device, such as e.g. a rotating wheel or a sliding filter, for fast synchronized switching between light in different wavelength bands or sets of wavelength bands.

Abstract: In one aspect, the present invention relates to a stereoscopic projection system including a projection device with at least one filter which filters a parameter of the light in a color selective manner. The at least one filter which filters a parameter of the light in a color selective manner has a spectral characteristic for transmitting light in a first wavelength band or set of wavelength bands and for reflecting light in a second wavelength band or set of wavelength bands. The projection device includes a device, such as e.g. a rotating wheel or a sliding filter, for fast synchronized switching between light in different wavelength bands or sets of wavelength bands.