Display that emits circularly-polarized light

• US 8,115,892 B2
• Filed: 01/31/2011
• Issued: 02/14/2012
• Est. Priority Date: 08/08/2006
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Zhong, John Z., Chen, Wei, Chen, Cheng, Yin, Victor H. E., Gettemy, Shawn R.
• Primary Examiner(s): PAK, SUNG H
• Application Number:
  US13/018,266
• Publication Number:
  US 20110124260A1
• Time in Patent Office: 379 Days
• Field of Search: None
• US Class Current: 349/98
• CPC Class Codes: G02F 1/13363 Birefringent elements, e.g. for optical compensation
• CPC Class Codes: G02F 1/133638 Waveplates, i.e. plates with a retardation value of lambda/n
• CPC Class Codes: G02F 2413/03 Number of plates being 3
• CPC Class Codes: G02F 2413/06 Two plates on one side of the LC cell

Abstract

One embodiment of the present invention provides a display that emits circularly-polarized light. This display includes a display mechanism that emits linearly-polarized light and a layer placed in the path of the linearly-polarized light. The layer receives the linearly-polarized light on one surface, converts the linearly-polarized light to circularly-polarized light, and then emits the circularly-polarized light from another surface. By emitting circularly-polarized light, the display reduces the perceived distortion found at some angles when the display is viewed through a linearly-polarizing filter.

Claims

1. A method for manufacturing a display that emits circularly-polarized light, comprising:

forming a display mechanism that emits linearly-polarized light;

forming a layer that circularly polarizes light coupled to the display mechanism, wherein the layer that circularly polarizes light is configured to convert the linearly-polarized light emitted from the display mechanism to circularly-polarized light; and

forming one or more a-plates coupled to the layer that circularly polarizes light;

wherein the display reduces perceived distortion when the display is viewed through a linearly-polarizing filter.

2. The method of claim 1, wherein forming the layer that circularly-polarizes light comprises:

forming a retardation film;

wherein the retardation film has a higher refractive index in a first direction than in a second direction perpendicular to the first direction.

3. The method of claim 2, wherein forming the layer that circularly-polarizes light comprises aligning the first direction in the retardation film 45 degrees with respect to a plane of the linearly-polarized light emitted by the display mechanism.

4. The method of claim 3, wherein forming the retardation film further comprises configuring a thickness of the retardation film to convert linearly-polarized light to circularly-polarized light.

5. The method of claim 1, wherein forming the layer that circularly-polarizes light further comprises one of:

laminating or bonding the layer that circularly-polarizes light to the display mechanism;

placing the layer that circularly-polarizes light in front of the display; and

incorporating the layer that circularly-polarizes light into a display cover removeably coupled to the display mechanism.

6. The method of claim 1, wherein forming the display mechanism further comprises:

forming at least one transmissive mechanism coupled to the display mechanism, wherein the transmissive mechanism is configured to generate and transmit light, and to function as a source of light for the display mechanism.

7. The method of claim 6, wherein forming the at least one transmissive mechanism comprises forming at least one backlight.

8. The method of claim 1, wherein forming the display mechanism further comprises:

forming at least one reflective mechanism coupled to the display mechanism, wherein the reflective mechanism is configured to selectively reflect external light, and to function as a source of light for the display mechanism.

9. The method of claim 1, wherein forming the display mechanism further comprises:

forming at least one transmissive mechanism coupled to the display mechanism, wherein the transmissive mechanism is configured to generate and transmit light; and

forming at least one reflective mechanism coupled to the display mechanism, wherein the reflective mechanism is configured to selectively reflect external light;

wherein the transmissive mechanism and the reflective mechanism selectively function as a source of light for the display mechanism.

10. The method of claim 1, wherein forming the display mechanism comprises:

forming a liquid crystal layer; and

forming a polarizing layer coupled to the liquid crystal layer, wherein the polarizing layer is configured to linearly polarize light to the liquid crystal layer.

11. The method of claim 10, wherein the method further comprises:

forming transparency-controlling circuitry coupled to the liquid crystal layer, wherein the transparency-controlling circuitry is configured to control a transparency of the liquid crystal layer.

12. The method of claim 1, wherein the method further comprises:

coupling the display that emits circularly-polarized light to a device, wherein the display that emits circularly-polarized light is configured as a display for the device.

13. The method of claim 1, wherein forming a layer that circularly polarizes light comprises:

injection-molding a predetermined material to form the layer that circularly polarizes light, wherein the injection-molding comprises using a directional control to form the layer that circularly polarizes light using flow-induced birefringence.