Arrangement for polarization of light
The invention is directed to an arrangement for the polarization of light, preferably for use in projectors. It comprises at least one illumination source, an integrator with a structural component part which is arranged in the light entrance plane, has the entrance opening, and is constructed so as to be reflecting in the direction of the interior of the integrator, as well as components for the polarization and reflection of partial beams of the light bundle entering the integrator. According to the invention, at least two reflecting polarizers are arranged in the light exit plane of the integrator in the same angular position relative to the axis of the integrator. The polarizers have polarization directions that are rotated relative to one another. Phase plates which adapt the polarizers with non-transmitted polarization directions to the polarizers with transmitted polarization directions are provided outside of the integrator.
1. An arrangement for the polarization of light, for use in projectors, comprising:
at least one illumination source;
an integrator with a light entrance plane and a light exit plane which serves to homogenize the unpolarized light bundle coming from the illumination source and/or illumination sources;
a structural component part which has an entrance opening and which is constructed so as to be reflecting in the direction of the interior of the integrator, and the intensity maximum of the light bundle propagates along an axis extending between the light entrance plane and the light exit plane;
said structural component having surfaces formed so as to be reflecting for guiding the light bundle;
means for polarization and reflection of partial beams of the light bundle entering the integrator; and
at least two reflecting polarizers being arranged in the light exit plane of the integrator in the same angular position relative to the axis of the integrator, the polarizers having polarization directions that are rotated relative to one another, and phase plates which adapt the polarizers with non-transmitted polarization directions to the polarizers with transmitted polarization directions being provided outside of the integrator.
2. The arrangement for the polarization of light according to claim 1 , wherein two horizontally and/or vertically divided polarizers of identical size with polarization directions which are rotated by 90 degrees relative to one another are arranged in the light exit plane of the integrator, wherein the transmitted polarization direction of the first polarizer parallel to the reflecting polarization direction of the second polarizer and, outside of the integrator, the polarizer is completely covered by a phase plate which rotates the polarization direction of the second polarizer in the polarization direction of the first polarizer.
3. The arrangement for the polarization of light according to claim 1 , wherein the polarizers and/or the phase plates are constructed as reflecting sheets.
4. The arrangement for the polarization of light according to claim 1 , wherein the polarizers are wire-grid polarizers.
5. The arrangement for the polarization of light according to claim 1 , wherein the light entrance opening is circular.
6. The arrangement for the polarization of light according to claim 1 , wherein a phase plate is arranged on the structural component part having the light entrance opening on the side of the structural component part that is oriented in the interior of the integrator, said phase plate having a characteristic that it rotates the polarization direction of the proportion of light that is reflected by the polarizers fastened in the light exit plane by 90 degrees when passing twice through the integrator.
7. The arrangement for the polarization of light according to claim 6 , wherein the phase plate has an opening analogous to the construction of the entrance opening.