Patent ID: 11906892
Assignee: APPOTRONICS CORPORATION LIMITED
Field: Optics (Instruments)
Classification: CPC G | IPC G

Claim 19:
20. A projection system comprising a projector and a total reflection screen for reflecting projection light from the projector into a field of view of a viewer,
wherein the total reflection screen comprises a light diffusing layer, a total reflection layer, and a light absorbing layer that are arranged sequentially from an incident side for the projection light,
wherein the light absorbing layer is configured to absorb incident light, and the light diffusing layer is configured to increase a divergence angle of emergent light,
wherein the total reflection layer comprises at least a microstructure layer located on a side of the total reflection layer close to the light diffusing layer and an inner layer located on a side of the total reflection layer close to the light absorbing layer, wherein a refractive index of the microstructure layer is greater than that of the inner layer, and the microstructure layer is provided with a plurality of microstructure units thereon which extend continuously in a plane of the total reflection screen and are rotationally symmetrical, wherein each of the microstructure units comprises two intersecting planes which are configured in such a manner that the projection light is totally reflected at both of the two intersecting planes successively, wherein the microstructure layer of the plurality of microstructure units is provided as total reflection prisms which are rotationally symmetrical, wherein angles between each of the two intersecting planes and the plane of the total reflection screen are θ1 and θ2 respectively, and
wherein the θ1 for each of the plurality of the microstructure units is different from each other.