Patent ID: 11860526
Assignee: BEIJING ASU TECH CO. LTD.
Field: Audio-visual technology (Electrical engineering)
Classification: CPC G  H | IPC G  H

Claim 0:
1. A projection system, comprising a beam modulation apparatus, a polarization modulation apparatus, a polarization apparatus, and a light source apparatus, wherein:
the beam modulation apparatus is configured for modulating an input light field entering thereinto along a first axis so as to obtain an output light field exiting therefrom along a second axis orthogonal to the first axis, wherein the input light field comprises a first light field and a second light field, wherein one of the first light field and the second light field has an S-polarization state, and another of the first light field and the second light field has a P-polarization state, wherein the beam modulation apparatus comprises:
a polarizing beam splitter (PBS) prism, comprising two right-angle prisms attached with each other on respective base surfaces thereof, arranged such that both the first axis and the second axis have substantially 45° relative to an interface between the two right-angle prisms, wherein the PBS prism is provided with an optical incident surface allowing the input light field to enter therethrough and an optical exit surface allowing the output light field to exit therefrom, and the interface of the PBS prism is configured to selectively allow a P-polarized incoming light to transmit therethrough and an S-polarized incoming light to reflect thereby; and
a liquid crystal on silicon (LCOS) assembly, comprising a first LCOS panel and a second LCOS panel, wherein the first LOOS panel is over a first side surface of the PBS prism opposing to the optical incident surface, aligned such that a light incident thereon is reflected back towards the PBS prism along the first axis; the second LCOS panel is over a second side surface of the PBS prism opposing to the optical exit surface, aligned such that a light incident thereon is reflected back towards the PBS prism along the second axis; and each of the first LCOS panel and the second LCOS panel comprises a plurality of pixels over a reflective surface thereof, wherein each of the plurality of pixels is configured to be controllably switched on or off such that a polarity state of a light beam reflected by a portion of the reflective surface corresponding thereto is changed or remains unchanged;

the polarization modulation apparatus is configured, upon receiving a third light field and a fourth light field having a substantially same polarization state, to modulate a polarization state of one, but not another, of the third light field and the fourth light field to correspondingly output the first light field and the second light field respectively;
the polarization apparatus is configured to polarize a non-polarized fifth light field and a non-polarized sixth light field incident thereinto to correspondingly output the third light field and the fourth light field respectively; and
the light source apparatus is configured to provide the fifth light field and the sixth light field, wherein the fifth light field and the sixth light field are configured to together form a white light field, wherein the fifth light field is a time-sharing coupling light field comprising a first primary colour light and a second primary colour light; and the sixth light field comprises a third primary colour light.