Light polarization converter
AssigneeSharp Laboratories of America, Inc.
InventorAustin Lancelot Huang
Life of this patent
Estimating the term…
Abstract
A polarizer is made from pairs of polarizing beam splitting cubes. In every pair, a first cube transmits P-polarized light and reflects S-polarized light. A retarder rotates the transmitted light to become S-polarized. A second cube receives only the reflected light, and redirects it in the direction of the transmitted light. A polarizing filter filters the reflected light, but not the rotated light. Exposing the retarder improves the transmission throughput of the overall polarizer. A stop at the side of the second cube blocks light from entering the first cube of an adjacent pair.
Claims7
A light polarizer comprising:
- a first polarizing beam splitting (PBS) cube having a front surface, a rear surface, a side surface, and a hypotenuse surface between the front surface and the rear surface for receiving incident light through the front surface, the hypotenuse surface for transmitting at least a portion of the received light through the rear surface, the hypotenuse surface further for reflecting at least a portion of the received light to travel along a reflection direction through the side surface;
- a retarder for changing a polarization of the light exiting through the rear surface of the PBS cube;
- a reflector for reflecting the light exiting through the side surface along the reflection direction of the PBS cube;
- and
- a polarizing filter for filtering at least a portion of the light reflected by the reflector, while not filtering at least a portion of the light having a changed polarization due to the retarder.
A light polarizer comprising:
- a plurality of pairs of polarizing beam splitting (PBS) cubes, each pair comprising a main PBS cube and an auxiliary PBS cube, the main PBS cube for receiving incident light along an incident direction and for transmitting a portion of the incident light along the incident direction, the main PBS cube further reflecting a portion of the incident light along a reflection direction, the auxiliary PBS cube receiving the light traveling along the reflection direction and reflecting it;
- at least one stop for preventing the incident light from reaching at least a portion of at least one of the auxiliary cubes along the incident direction;
- at least one retarder for changing a polarization of the light exiting along the incident direction from at least one of the main PBS cubes;
- and
- a polarizing filter for filtering at least a portion of the light reflected by at least one of the auxiliary PBS cubes, while not filtering at least a portion of the light exiting through the retarder.
Dependencies are inferred from the claim text.