Polarization preserving 3D screen

Patent metadata

Field	Value
Publication number	US-9417514-B2
Application number	US-201214349013-A
Country	US
Kind code	B2
Filing date	Oct 25, 2012
Priority date	Oct 27, 2011
Publication date	Aug 16, 2016
Grant date	Aug 16, 2016

Abstract

Projection 3D systems and polarization preserving 3D screens are described that substantially increase polarization contrast ratio and viewing angle. The screen comprises a structured surface having a certain slope distribution, formed by a plurality of beads 120 with a layer 115 disposed thereon, which is coated by a reflective layer 110.

First claim

What is claimed is:

1. A projection system comprising:
a projector projecting light having a first polarization state;
a front projection screen receiving the projected light from a viewing side of the front projection screen and reflecting the received light to a viewer, a ratio of the reflected light having the first polarization state to the reflected light having a second polarization state perpendicular to the first polarization state being at least 250, the front projection screen comprising:
a support layer;
a plurality of beads partially embedded in the support layer, unembedded portions of the beads being on the viewing side of the screen and defining a first structured surface having a first slope distribution;
a first layer disposed on the first structured layer and defining a second structured surface having a second slope distribution different than the first slope distribution, no more than about 5% of the second structured surface having a slope magnitude that is greater than about 30 degrees, at least 50% of the second structured surface having a slope magnitude that is greater than about 2 degrees; and
a reflective layer disposed on the second structured layer and reflecting the projected light received by the front projection screen.

2. The projection system of claim 1 , wherein the front projection screen further comprises a second layer disposed on the reflective layer.

3. The projection system of claim 2 , wherein the second layer defines a third structured surface having a third slope distribution different than the first and second slope distributions.

4. The projection system of claim 1 , wherein at least 50% of the first structured surface has a slope magnitude that is greater than about 20 degrees.

5. A front projection screen comprising:
a light absorbing layer absorbing at least 90% of visible light;
a support layer disposed on the light absorbing layer;
a plurality of beads partially embedded in the support layer, unembedded portions of the beads defining a first structured surface having a first slope distribution;
a first layer disposed on the first structured layer and defining a second structured surface having a second slope distribution different than the first slope distribution, no more than about 5% of the second structured surface having a slope magnitude that is greater than about 30 degrees, at least 50% of the second structured surface having a slope magnitude that is greater than about 2 degrees; and
a reflective layer disposed on the second structured layer.

6. The front projection screen of claim 5 being adapted to receive light having a first polarization state and reflect the received light such that a ratio of the reflected light having the first polarization state to the reflected light having a second polarization state perpendicular to the first polarization state is at least 250.

7. The front projection screen of claim 5 wherein the light absorbing layer absorbing at least 99% of visible light.

8. The front projection screen of claim 5 wherein at least 50% of the first structured surface having a slope magnitude that is greater than about 20 degrees.

9. A front projection screen comprising:
a support layer;
a plurality of beads partially embedded in the support layer and defining a first structured surface having a first slope distribution, at least 50% of the first structured surface having a slope magnitude that is greater than about 20 degrees;
a first layer disposed on the first structured layer and defining a second structured surface having a second slope distribution different than the first slope distribution, no more than about 5% of the second structured surface having a slope magnitude that is greater than about 30 degrees, at least 50% of the second structured surface having a slope magnitude that is greater than about 2 degrees;
a reflective layer disposed on the second structured layer; and
a second layer disposed on the reflective layer and defining a third structured surface having a third slope distribution different than the first and second slope distributions.

10. The front projection screen of claim 9 being adapted to receive light having a first polarization state and reflect the received light such that a ratio of the reflected light having the first polarization state to the reflected light having a second polarization state perpendicular to the first polarization state is at least 250.

Assignees

• 3M Innovative Properties Co

Inventors

• Liu Richard Y
• Miller Alan P

Classifications

• G02B30/25

  using polarisation techniques · CPC title

• G03B21/604 Primary

  Polarised screens · CPC title

• G02B27/26

  Physics · mapped topic