PROJECTION DEVICE FOR PROJECTING AN IMAGE

摘要

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.