Auto-stereoscopic display device

Patent metadata

Field	Value
Publication number	US-9807377-B2
Application number	US-68022808-A
Country	US
Kind code	B2
Filing date	Sep 30, 2008
Priority date	Oct 2, 2007
Publication date	Oct 31, 2017
Grant date	Oct 31, 2017

Abstract

An auto-stereoscopic display device includes a display panel having an array of display pixels for producing a display; and a view forming unit having an array of view forming elements. Each view forming elements is configurable to focus the outputs of groups of the display pixels into views projected towards a user in different directions. The display device further includes a view deflecting unit to selectably change the directions in which the plurality of views is projected towards the user. The view deflecting unit includes at least one birefringent prism having a first refractive index for light having a first polarization direction and a second refractive index for light having a second polarization direction. The view deflecting unit further includes a polarization switch in registration with the birefringent prism for providing the birefringent prism with display light having the first or second polarization direction.

First claim

The invention claimed is:

1. A multi-view auto-stereoscopic display device, comprising:
an image forming means that includes an array of display pixels for producing a display,
view forming means positioned over the image forming means and having an array of view forming elements, the view forming elements each being configurable to focus outputs of groups of the display pixels into a plurality of views projected towards a user in different directions; and
view deflecting means positioned over the view forming means, the view deflecting means being arranged to selectably change the directions in which the plurality of views including successive views are projected from an output surface of the multi-view auto-stereoscopic display device towards the user resulting in a shift X shift,view which is a difference between values of X view for the successive views where a first projected view is next to a second projected view, X view being a horizontal distance between a center of a display pixel of one of the groups of the display pixels which generates a view and an axis of an associated view forming element of the array of view forming elements,
wherein the view deflecting means comprise at least one birefringent prism having simultaneously a first refractive index for light having a first polarization direction and a second refractive index for light having a second polarization direction, the view deflecting means further comprising a polarization switch and at least one optically isotropic prism, the polarization switch being in registration with the birefringent prism for directly providing the birefringent prism with display light selectably having the first or second polarization direction, the display light passing from the at least one birefringent prism to the at least one optically isotropic prism for direct exit from the output surface towards the user, the at least one optically isotropic prism being more optically isotropic than the at least one birefringent prism,
wherein the view forming means are arranged between the image forming means and the view deflecting means,
wherein the array of view forming elements comprises an array of lenticular lenses and wherein the image forming means is arranged adjacent to a convex surface of the lenticular lenses, and the view deflecting means is arranged adjacent to a plane surface of the lenticular lenses,
wherein the view forming means is configurable to project the plurality of views in directions that are separated by constant angles, and wherein the view deflecting means is arranged to selectably change the directions in which the plurality of views are projected by the substantially constant angles, and
wherein separation angles between consecutive views of the plurality of views projected by the view forming means are substantially double deflection angles by which the plurality of views are changed by the view deflecting means,
wherein the at least one birefringent prism comprises a first surface for receiving light into the at least one birefringent prism and a second surface for transmitting light out from the at least one birefringent prism, the first surface contacting the second surface to form an acute angle,
wherein the at least one isotropic prism comprises a third surface and the output surface, the third surface receiving light into the at least one isotropic prism from the second surface, and the output surface being an outer surface of the multi-view auto-stereoscopic display device and transmitting light of the different directions out directly from the at least one isotropic prism towards the user, the third surface contacting the output surface to form the acute angle.

2. The multi-view auto-stereoscopic display device according to claim 1 , wherein the polarization switch comprises a switchable polarization rotator arranged to selectably change the polarization direction of transmitted light from the first direction to the second direction.

3. The multi-view auto-stereoscopic display device arrangement according to claim 2 , wherein the switchable polarization rotator comprises a liquid crystal material disposed between transparent electrodes.

4. The multi-view auto-stereoscopic display device according to claim 1 , wherein the at least one optically isotropic prism has the same refractive index for the light having the first and second polarization directions, the refractive index of the at least one optically isotropic prism being substantially either the first or second refractive index.

5. The multi-view auto-stereoscopic display device according to claim 1 , further comprising a driving means arranged to drive the image forming means with display data for a plurality of views and control the view deflecting means to project the plurality of views in different directions.

6. The multi-view auto-stereoscopic display device according to claim 5 , wherein the driving means are arranged to drive the image forming means with display data for first and second pluralities of views, and to control the view deflecting means to project the first and second pluralities of views in different directions.

7. The multi-view auto-stereoscopic display device according to claim 5 , wherein the driving means are arranged to:
in a first portion of a driving cycle, drive the image forming means with a first frame of display data for a first plurality of views and control the view deflecting means so that the plurality of views are projected towards the user in a first plurality of directions; and
in a second portion of the driving cycle, drive the image forming means with a second frame of display data for a second plurality of views and control the view deflecting means so that the plurality of views are projected towards the user in a second plurality of directions different to the first plurality of directions.

8. The multi-view auto-stereoscopic display device according to claim 7 , wherein the first and the second frames of display data are the same.

9. A driving device for the multi-view auto-stereoscopic display device according to claim 1 , the driving device comprising:
driving means for driving the image forming means with display data; and
a deflection controller for controlling the view deflecting means to change the directions in which the plurality of views formed by the view forming means are projected towards the user.

10. A method for driving a multi-view auto-stereoscopic display device, the method comprising acts of:
forming an imager that includes an array of display pixels for producing a display;
forming an array of view forming elements positioned over the imager, the view forming elements each being configurable to focus outputs of groups of the display pixels into a plurality of views projected from an output surface of the multi-view auto-stereoscopic display device towards a user in different directions;
forming deflector positioned over the array of view forming elements, the deflector being arranged to selectably change the directions in which the plurality of views including successive views are projected towards the user resulting in a shift X shift,view which is a difference between values of X view for the successive views where a first projected view is next to a second projected view, X view being a horizontal distance between a center of a display pixel of one of the groups of the display pixels which generates a view and an axis of an associated view forming element of the array of view forming elements;
driving the imager with display data; and
controlling the deflector to change the directions in which the plurality of views formed by the view forming elements are projected towards the user,
wherein the defle

Assignees

• Hiddink Martin Gerard Hendrik
• De Zwart Siebe Tjerk
• Willemsen Oscar Hendrikus
• Vissenberg Michel Cornelis Josephus Marie
• Kraan Thomas Caspar
• Op De Beeck Marc Joseph Rita
• Muijs Remco Theodorus Johannes
• Koninklijke Philips Nv

Inventors

• Hiddink Martin Gerard Hendrik
• De Zwart Siebe Tjerk
• Willemsen Oscar Hendrikus
• Vissenberg Michel Cornelis Josephus Marie
• Kraan Thomas Caspar
• Op De Beeck Marc Joseph Rita
• Muijs Remco Theodorus Johannes

Classifications

• G02F1/1335 Primary

  Structural association of cells with optical devices, e.g. polarisers or reflectors · CPC title

• G02B30/54

  the three-dimensional [3D] volume being generated by moving a two-dimensional [2D] surface, e.g. by vibrating or rotating the 2D surface · CPC title

• H04N13/305

  using lenticular lenses, e.g. arrangements of cylindrical lenses · CPC title

• H04N13/312 Primary

  the parallax barriers being placed behind the display panel, e.g. between backlight and spatial light modulator [SLM] · CPC title

• G02B30/36

  using refractive optical elements, e.g. prisms, in the optical path between the images and the observer · CPC title