Color projection system incorporation electro-optic light modulator and rotating light-reflective element

• US 6,266,105 B1
• Filed: 07/31/1998
• Issued: 07/24/2001
• Est. Priority Date: 07/31/1998
• Status: Expired due to Fees

• Current Assignee: Philips Electronics North America Corporation (Koninklijke Philips N.V.)
• Original Assignee: Philips Electronics North America Corporation (Koninklijke Philips N.V.)
• Inventors: Gleckman, Philip
• Primary Examiner(s): Lee, Michael
• Application Number:
  US09/127,003
• Time in Patent Office: 1,089 Days
• Field of Search: H04/N.912, 348/743, 348/742, 348/744, 348/759, 353/84
• US Class Current: 348/743
• CPC Class Codes: H04N 9/3117 by using a sequential colour filter producing two or more colours simultaneously, e.g. by creating scrolling colour bands

Abstract

A color projection system, comprising a rotatable color drum with reflective segments on the surface of the drum, the segments composed of dichroic filters having different color reflection bands, and means for focussing images of the segments onto a reflective electro-optical light modulator panel, whereby in operation the segment images are scrolled across the surface of the light modulator, synchronously with the application of color components of a display signal corresponding to the colors of the scrolling segment images, to produce a full color display image.

Claims

1. A color projection system, comprising:

a light source;

a rotationally-symmetric element having an axis of rotation and reflective surface portions substantially perpendicular to the axis of rotation, the reflective surface portions comprising a plurality of mutually different color reflection bands capable of reflecting light from the light source as a respective plurality of mutually different color bands;

the first optical circuit disposed to direct light from the source onto the reflective surface portions;

a rotator disposed for rotating the rotationally-symmetric element about the axis of rotation;

a display-image producing electro-optical light modulator panel; and

a second optical circuit disposed to direct light reflected from the reflective surface portions onto the light modulator panel.

the color projection system being operable to scroll the color bands reflected from the rotating element across the panel.

2. The color projection system of claim 1 in which the reflective surface portions are curved surface portions.

3. The color projection system of claim 2 in which the curvature of the reflective portions matches that of the element surface.

4. The color projection system of claim 1 in which the reflective surface portions are cylindrically curved surface portions.

5. The color projection system of claim 1 in which the reflective portions of the surface comprise diachronic filters.

6. The color projection system of claim 5 in which the diachronic filters are formed on a support, and the support is bonded to the surface of the element.

7. The color projection system of claim 5 in which the diachronic filters have color reflection bands.

8. The color projection system of claim 5 in which the diachronic filters have color transmission bands.

9. The color projection system of claim 1 in which the first optical circuit includes a cylindrical lens.

10. The color projection system of claim 1 comprising a light integrator to integrate light from the source into a telecentric beam.

11. The color projection system of claim 1 comprising a polarization element to convert light from the source into P type polarized light.

12. The color projection system of claim 1 comprising a polarization element to convert light from the source into S type polarized light.

13. The color projection system of claim 1 in which the first optical circuit includes a telephoto lens set.

14. A color projection system, comprising:

a light source;

a rotationally-symmetric element having an axis of rotation and curved reflective surface portions, the reflective surface portions comprising a plurality of mutually different color reflection bands capable of reflecting light from the light source as a respective plurality of mutually different color bands;

the first optical circuit disposed to direct light from the source onto the reflective surface portions;

a rotator disposed for rotating the rotationally-symmetric element about the axis of rotation;

a display-image producing electro-optical light modulator panel; and

a second optical circuit disposed to direct light reflected from the reflective surface portions onto the light modulator panel,

the color projection system being operable to scroll the color bands reflected from the rotating element across the panel.

15. The color projection system of claim 14 in which the curvature of the reflective portions matches that of the element surface.

16. The color projection system of claim 14 in which the reflective surface portions are cylindrically curved surface portions.

17. The color projection system of claim 14 in which the reflective portions of the surface comprise diachronic filters.

18. The color projection system of claim 14 in which the first optical circuit includes a cylindrical lens.

19. The color projection system of claim 14 comprising a light integrator to integrate light from the source into a telecentric beam.

20. The color projection system of claim 14 comprising a polarization element to convert light from the source into polarized light.