Image display system and method

• US 7,773,160 B2
• Filed: 02/01/2007
• Issued: 08/10/2010
• Est. Priority Date: 10/14/1995
• Status: Expired due to Fees

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Hirakata, Yoshiharu, Teramoto, Satoshi, Koyama, Jun, Yamazaki, Shunpei
• Primary Examiner(s): LEE, MICHAEL
• Application Number:
  US11/669,977
• Publication Number:
  US 20070126986A1
• Time in Patent Office: 1,286 Days
• Field of Search: 348 51- 60, 348832-835, 348744-762, 359/465, 359/464, 353/20, 349/96
• US Class Current: 348/752
• CPC Class Codes: G03B 21/006 using LCD's
• CPC Class Codes: G09G 3/001 using specific devices not provided for in groups G09G3/02 - G09G3/36, e.g. using an intermediate record carrier such as a film slide; Projection systems; Display of non-alphanumerical information, solely or in combination with alphanumerical information, e.g. digital display on projected diapositive as background slide projectors per se G03B23/00 = 42 HP
• CPC Class Codes: G09G 3/002 to project the image of a two-dimensional display, such as an array of light emitting or modulating elements or a CRT
• CPC Class Codes: G09G 3/003 to produce spatial visual effects
• CPC Class Codes: G09G 3/3648 using an active matrix G09G3/367 - G09G3/3696 take precedence
• CPC Class Codes: G09G 3/3666 with the matrix divided into sections
• CPC Class Codes: H04N 13/341 using temporal multiplexing
• CPC Class Codes: H04N 13/398 Synchronisation thereof; Control thereof
• CPC Class Codes: H04N 9/3102 using two-dimensional electronic spatial light modulators micromechanical modulators as such G02B26/0833; liquid crystal modulators as such G02F1/13
• CPC Class Codes: H04N 9/3141 Constructional details thereof details not peculiar to the presence of an electronic spatial light modulator G03B21/14
• CPC Class Codes: H04N 9/3147 Multi-projection systems displays in general H04N9/12; video walls G06F3/1446, G09G2300/026

Abstract

An image display system comprises a first liquid crystal projector which projects a counterclockwise-rotating, circularly polarized light beam to form an image containing specific visual information on a screen and a second liquid crystal projector which projects a clockwise-rotating, circularly polarized light beam to form a white image on the same screen. When viewed with the naked eye, a combination of the two images projected on the screen appears totally white. A viewer wearing a dedicated viewing device equipped with an optical filter which allows counterclockwise-rotating, circularly polarized light to pass through can selectively see the image projected by the first liquid crystal projector.

Claims

1. A display device comprising:

a light source;

a panel comprising a first region and a second region, wherein the light source and the first region are configured to project a first image, and wherein the light source and the second region are configured to project a second image;

a first quarter-wave plate arranged to give a clockwise-rotating circular polarization to the first image;

a second quarter-wave plate arranged to give a counterclockwise-rotating circular polarization to the second image; and

a screen on which the first image and the second image are projected,

wherein one of the first image and the second image is monochrome or in color,

wherein the other of the first image and the second image is white, and

wherein the first image overlaps the second image on the screen.

5. The display device according to claim 1, further comprising a π

-cell between the panel and the screen.

2. A display device comprising:

a light source;

a panel comprising a first region, a second region, and a control circuit arranged to control operations of the first region and the second region, wherein the light source and the first region are configured to project a first image, and wherein the light source and the second region are configured to project a second image;

a first quarter-wave plate arranged to give a clockwise-rotating circular polarization to the first image;

a second quarter-wave plate arranged to give a counterclockwise-rotating circular polarization to the second image; and

a screen on which the first image and the second image are projected,

wherein one of the first image and the second image is monochrome or in color,

wherein the other of the first image and the second image is white, and

wherein the first image overlaps the second image on the screen.

6. The display device according to claim 2, further comprising a π

-cell between the panel and the screen.

3. A display device comprising:

a light source;

a panel comprising a first region and a second region each of which comprises a thin film transistor, wherein the light source and the first region are configured to project a first image, and wherein the light source and the second region are configured to project a second image;

a first quarter-wave plate arranged to give a clockwise-rotating circular polarization to the first image;

a second quarter-wave plate arranged to give a counterclockwise-rotating circular polarization to the second image; and

a screen on which the first image and the second image are projected,

wherein one of the first image and the second image is monochrome or in color,

wherein the other of the first image and the second image is white, and

wherein the first image overlaps the second image on the screen.

7. The display device according to claim 3, further comprising a π

-cell between the panel and the screen.

4. A display device comprising:

a light source;

a panel comprising a first region, a second region, and a control circuit arranged to control operations of the first region and the second region, wherein the light source and the first region are configured to project a first image, and wherein the light source and the second region are configured to project a second image;

a first quarter-wave plate arranged to give a clockwise-rotating circular polarization to the first image;

a second quarter-wave plate arranged to give a counterclockwise-rotating circular polarization to the second image; and

a screen on which the first image and the second image are projected,

wherein each of the first image portion and the second image portion comprises a first thin film transistor,

wherein the control circuit comprises a second thin film transistor,

wherein one of the first image and the second image is monochrome or in color,

wherein the other of the first image and the second image is white, and

wherein the first image overlaps the second image on the screen.

8. The display device according to claim 4, further comprising a π

-cell between the panel and the screen.