Color filters, sequencers and displays using color selective light modulators

• US 6,667,784 B2
• Filed: 03/19/2002
• Issued: 12/23/2003
• Est. Priority Date: 05/23/1995
• Status: Expired due to Fees

• Current Assignee: RealD Incorporated
• Original Assignee: ColorLink, Incorporated (RealD Incorporated)
• Inventors: Sharp, Gary D., Johnson, Kristina M.
• Primary Examiner(s): Parker, Kenneth
• Application Number:
  US10/100,023
• Publication Number:
  US 20020101546A1
• Time in Patent Office: 644 Days
• Field of Search: 349/119, 349/78, 349/79, 349/80
• US Class Current: 349/78
• CPC Class Codes: G02B 27/288 Filters employing polarising elements, e.g. Lyot or Solc filters G02B5/3016 takes precedence
• CPC Class Codes: G02F 1/0136 for the control of polarisation, e.g. state of polarisation [SOP] control, polarisation scrambling, TE-TM mode conversion or separation G02F1/0353 takes precedence
• CPC Class Codes: G02F 1/0322 Arrangements comprising two or more independently controlled crystals
• CPC Class Codes: G02F 1/09 based on magneto-optical elements, e.g. exhibiting Faraday effect
• CPC Class Codes: G02F 1/133533 Colour selective polarisers G02F1/1347 takes precedence
• CPC Class Codes: G02F 1/133536 Reflective polarizers G02F1/13362 takes precedence
• CPC Class Codes: G02F 1/133543 Cholesteric polarisers
• 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 1/13473 for wavelength filtering or for colour display without the use of colour mosaic filters
• CPC Class Codes: G02F 1/23 for the control of the colour G02F1/03 - G02F1/21 take precedence
• CPC Class Codes: G02F 2413/04 Number of plates greater than or equal to 4
• CPC Class Codes: G02F 2413/08 with a particular optical axis orientation
• CPC Class Codes: H04N 5/66 Transforming electric information into light information scanning details H04N3/00
• CPC Class Codes: H04N 5/7441 the modulator being an array of liquid crystal cells
• CPC Class Codes: H04N 9/3111 for displaying the colours sequentially, e.g. by using sequentially activated light sources sequential projection in colour photography G03B33/08
• CPC Class Codes: H04N 9/3126 for spatial light modulators in series
• CPC Class Codes: H04N 9/3167 for polarizing the light beam polarizing optical systems per se G02B27/28

Abstract

The present invention provides a high brightness color selective light modulator (CSLM) formed by apolarization modulator positioned between two retarder stacks. The modulator changes the apparent orientation of one retarder stack relative to the other so that, in a first switching state of the modulator the two retarder stacks cooperate in filtering the spectrum of input light, and in a second switching state the two retarder stacks complement each other, yielding a neutral transmission spectrum. Two or more CSLM stages can be used in series, each stage providing independent control of a primary color. One preferred embodiment eliminates internal polarizers between CSLM stages, thereby providing an additive common-path full-color display with only two neutral polarizers. Hybrid filters can be made using the CSLMs of this invention, in combination with other active or passive filters. The CSLMs of this invention can be used in many applications, particularly in the areas of recording and displaying color images. They can be arranged in a multi pixel array by pixelating the active elements, and can be implemented as color filter arrays, using patterned passive retarders rather than active polarization modulators.

Claims

1. A direct view display comprising:

a light source that generates input light comprising a plurality of spectral components;

an output polarizer;

an input polarizer disposed between said light source and said output polarizer;

a first imaging stage, disposed between said input polarizer and said output polarizer, that receives the input light and outputs first stage light having the plurality of spectral components, said first imaging stage comprising;

a first transmissive display,

a first retarder stack, positioned at an input side of the first transmissive display, that preconditions a polarization of the input light such that the first transmissive display can selectively interact with a subset of the plurality of spectral components, and

a second retarder stack positioned at an output side of the first transmissive display;

a second imaging stage, disposed between said first imaging stage and said output polarizer, that receives the first stage light and outputs second stage light having the plurality of spectral components, said second imaging stage comprising;

a second transmissive display,

a third retarder stack, positioned at an input side of the second transmissive display, that preconditions a polarization of the first stage light such that the second transmissive display can selectively interact with a subset of the plurality of spectral components, and

a fourth retarder stack positioned at an output side of the second transmissive display; and

a third imaging stage, disposed between said second imaging stage and said output polarizer, that receives the second stage light and outputs third stage light having the plurality of spectral components, said third imaging stage comprising;

a third transmissive display,

a fifth retarder stack, positioned at an input side of the third transmissive display, that preconditions a polarization of the second stage light such that the third transmissive display can selectively interact with a subset of the plurality of spectral components, and

a sixth retarder stack positioned at an output side of the third transmissive display.

2. The display of claim 1, wherein the orientation of said output polarizer is orthogonal to the orientation of said input polarizer.

3. The display of claim 1, wherein the first transmissive display is driven with a first spectral image information, the second transmissive display is driven with a second spectral image information, and the third transmissive display is driven with a third spectral image information.

4. The display of claim 3, wherein the first retarder stack pre-conditions a polarization of a first spectral component of the input light for interaction with the first transmissive display, the third retarder stack pre-conditions a polarization of a second spectral component of the input light for interaction with the second transmissive display, and the fifth retarder stack pre-conditions a polarization of a third spectral component of the input light for interaction with the third transmissive display.

5. The display of claim 4, wherein the first, second, and third spectral components comprise first, second, and third color components, respectively.

6. The display of claim 5, wherein the first, second, and third color components comprise blue, green, and red color components, respectively.

7. The display of claim 1, wherein the first, second, and third transmissive displays comprise active matrix liquid crystal displays.

8. The image display apparatus of claim 1, wherein the first, second, and third transmissive displays comprise passive matrix liquid crystal displays.

9. The image display apparatus of claim 1, wherein the first, second, third, fourth, fifth, and sixth retarder stacks each comprise birefringent liquid crystal polymer.

10. A direct view display comprising:

a light source that generates input light comprising a first spectral component, a second spectral component, and a third spectral component;

an output polarizer;

an input polarizer disposed between said light source and said output polarizer;

first imaging means disposed between said input polarizer and said output polarizer that selectively manipulates said first spectral component, and that is substantially transparent to said second and third spectral components;

second imaging means disposed between said first imaging means and said output polarizer that selectively manipulates said second spectral component and that is substantially transparent to said first and third spectral components; and

,

third imaging means disposed between said imaging second means and said output polarizer that selectively manipulates said third spectral component and is substantially transparent to said first and second spectral components.

11. The display of claim 10, wherein the first, second, and third spectral component comprise first, second, and third color components.

12. The display of claim 11, wherein each of the first, second, and third color components comprise one of a blue, green, and red component.