Patent attributes
The invention relates to a projection device for projecting an image, comprising an illumination means (1) having an entrance (13) for entering light from a light source, a polarization-selective mirror (3) for transmitting a first polarization component (42) of the light to a display panel (4) and reflecting a second component (43) back to the illumination means (1), and a display panel (4) for selecting colour components of the first polarization component for projection at a projection means (7). The display panel comprises a dichroic filter means (5) for filtering colour components of the first polarization component (42) and a controllable reflective means (6) for changing the state of polarization of the filtered colour components depending on a control signal and for reflecting the filtered colour components back to the polarization-selective mirror (3). All light that is reflected from the dichroic filter means (5) and the controllable reflective means (6) back to the polarization-selective mirror (3), having an unchanged state of polarization, is transmitted back to the illumination means (1). The reflected light having a changed state of polarization is reflected to the projection means (7) for projection.
