Abstract: An image projection system includes an illumination system and an image display system with at least one reflective image display panel for modulating. An illumination beam is supplied by the illumination system with image information and a projection lens system. The illumination system has an extra optical system that at least partly re-illuminates the image display system with light reflected by the reflective image display panel to the illumination system. The extra optical system redistributes light coming from a pixel of the image display system across a plurality of pixels of the image display system.

Abstract: Projection display device which comprises a light source for generating a light beam, integrator means for converting the light beam into a uniform rectangular beam, modulator means for modulating the rectangular light beam with the information to be displayed, and projection means for projecting the modulated rectangular light beam on a display plane. The integrator means comprises a triangular prism and an integrator device positioned between the light source and the triangular prism. The triangular prism is arranged for total internal reflection on at least one or more of its non-folding planes or, for best optical performance, on all of its non-folding planes.

Abstract: Projection system comprising at least two light sources, a projection lens and a spatial light modulator located between the light sources and the projection lens, which light modulator comprises a plurality of light-deflection devices each provided with an element which is tiltable about a tilt axis. The light sources are arranged with respect to the spatial light modulator in such a way that, in operation, the centers of the light beams coming from the light sources and projected on each element are located on a projection line which extends substantially parallel to the tilt axis of the element.

Abstract: A projection device comprising at least one light source, at least one light-modulation panel preceding the light source, and polarization-separating means arranged between said light source and said light-modulation panel for separating light from the light source into first and second light beams having a first and a second direction of polarization, respectively. The projection device also comprises first and second integrator plates comprising lens elements which are arranged between said polarization-separating means and said light-modulation panel, and polarization-converting means arranged opposite the second integrator plate. Each lens element of the second integrator plate includes a first portion on which a first light beam is projected by the first integrator plate, and a juxtaposed, second portion, on which a second light beam is projected. The polarization-converting means are arranged at least opposite said first portions.

Abstract: A projection system is provided with a square-wave current light source and a color wheel with differently colored segments. The lifetime of the light source is long since the square-wave current constantly changes polarity a constant power is supplied to the light source and, before changing polarity, a current pulse is each time provided, driving the square-wave current to a predetermined strength which is larger than the current strength in between the current pulses. In the course of time, the amount of power in the current pulses increases relative to the amount of power in the current in between the current pulses. By controlling the timing of occurrence of the current pulses to constantly coincide in time and, on average, an equal number of times with all colors of the color wheel, the position of the white color point is independent of the period of time of use of the light source.

Abstract: A projection device comprising at least one light source, at least one light-modulation panel preceding the light source, and polarization-separating means arranged between said light source and said light-modulation panel for separating light from the light source into first and second light beams having a first and a second direction of polarization, respectively. The projection device also comprises first and second integrator plates comprising lens elements which are arranged between said polarization-separating means and said light-modulation panel, and polarization-converting means arranged opposite the second integrator plate. Each lens element of the second integrator plate includes a first portion on which a first light beam is projected by the first integrator plate, and a juxtaposed, second portion, on which a second light beam is projected. The polarization-converting means are arranged at least opposite said first portions.

Abstract: A projection system is provided with a square-wave current light source and a color wheel with differently colored segments. The lifetime of the light source is long since the square-wave current constantly changes polarity a constant power is supplied to the light source and, before changing polarity, a current pulse is each time provided, driving the square-wave current to a predetermined strength which is larger than the current strength in between the current pulses. In the course of time, the amount of power in the current pulses increases relative to the amount of power in the current in between the current pulses. By controlling the timing of occurrence of the current pulses to constantly coincide in time and, on average, an equal number of times with all colors of the color wheel, the position of the white color point is independent of the period of time of use of the light source.