High intensity lighting projectors

• US 5,282,121 A
• Filed: 04/30/1991
• Issued: 01/25/1994
• Est. Priority Date: 04/30/1991
• Status: Expired due to Term

• Current Assignee: Vari-Lite, Inc. (Koninklijke Philips N.V.)
• Original Assignee: Vari-Lite, Inc. (Koninklijke Philips N.V.)
• Inventors: Bornhorst, James M., Hutton, Richard W., Stacy, Timothy D.
• Primary Examiner(s): Husar, Stephen F.
• Application Number:
  US07/693,366
• Time in Patent Office: 1,001 Days
• Field of Search: 353/30, 353/31, 353/54, 353/55, 359/51, 359/52, 359/66, 362/293, 362/294, 362/268, 362/318, 340/784
• US Class Current: 362/294
• CPC Class Codes: F21S 10/007 using rotating transparent or colored disks, e.g. gobo wheels
• CPC Class Codes: F21V 14/003 by interposition of elements with electrically controlled variable light transmissivity, e.g. liquid crystal elements or electrochromic devices
• CPC Class Codes: F21V 29/56 using liquid coolants F21V29/51 takes precedence
• CPC Class Codes: F21V 29/70 characterised by passive heat-dissipating elements, e.g. heat-sinks
• CPC Class Codes: F21V 9/04 for filtering out infrared radiation dichroic reflectors F21V7/22; using liquid-filled chambers F21V9/12
• CPC Class Codes: F21V 9/40 with provision for controlling spectral properties, e.g. colour, or intensity
• CPC Class Codes: F21W 2131/406 for theatres, stages or film studios
• CPC Class Codes: G02F 1/133385 with cooling means, e.g. fans
• CPC Class Codes: G02F 1/1334 based on polymer dispersed liquid crystals, e.g. microencapsulated liquid crystals
• CPC Class Codes: G02F 1/133509 Filters, e.g. light shielding masks
• CPC Class Codes: G03B 21/16 Cooling; Preventing overheating
• CPC Class Codes: H04N 5/7441 the modulator being an array of liquid crystal cells
• CPC Class Codes: H04N 9/3114 by using a sequential colour filter producing one colour at a time
• CPC Class Codes: H04N 9/3144 Cooling systems cooling of liquid crystal cells in general G02F1/133382; cooling of projectors not peculiar to the presence of an electronic spatial light modulator G03B21/16
• CPC Class Codes: H04N 9/3155 for controlling the light source light source control per se H05B35/00 – H05B47/00; control of an illumination source for displays in general G09G3/3406
• CPC Class Codes: H04N 9/3197 using light modulating optical valves

Abstract

A high intensity light projector for stage, architectural and similar applications includes a controllable image quality projection gate providing advanced visual effects. The projection gate, capable of selectively scattering or transmitting incident light, may be constructed of an array of scattering liquid crystal material in combination with infrared and ultraviolet reduction means which provide in the high intensity beam, a stable thermal environment by minimizing the absorption of light by the projection gate. Additional thermal efficiency is provided by supplemental cooling means. Color control is also provided in the form of dichroic filter wheels forming cooperating adjustable low, high and band width filters including saturation control. A color measuring feedback sensor is also provided. An intensity measuring feedback sensor controls a spatially-modulated, variable-density, reflectively-coated dimming wheel. A programmable gobo system has provisions for gobo selection, orientation, and rotation.

Claims

1. A light projection system for lighting applications having one or more light projectors which include image forming means, said one or more projectors comprising:

(1) a light beam source for generating an unpolarized light beam having an intensity suitable for lighting applications;

(2) a projection gate located to modulate said unpolarized light beam and having an addressable array of light scattering liquid crystal pixels in an essentially non-absorptive optical environment, said pixels being capable of assuming transparent and opaque states;

(3) an active heat control system for protecting said array of liquid crystals from the heat generated by said beam; and

(4) a source of image control signals connected to said array to control the states of said pixels to vary the image projected by said beam.

2. A system according to claim 1 including an essentially sealed housing enclosing said light projectors.

3. A light projection system according to claim 1 in which said active heat control system is thermostatically-controlled.

4. A light projection system according to claim 1 in which said light beam source has a power rating of about 1000 Watts.

5. A light projection system according to claim 1 in which said light beam source has a power rating greater than about 300 Watts.

7. A system according to claims 1 or 6 including beam color control means for controlling the color of the beam modulated by said liquid crystal array.

8. A system according to claims 1 or 6 in which said heat control system includes a liquid cell.

9. A system according to claims 1 or 6 in which said system includes means for diverting radiant energy in the infrared range or the ultraviolet range from said array.

10. A system according to claims 1 or 6 in which said system includes a dielectric interference filter having dichroic properties for protecting said array for potentially damaging radiant energy.

11. A system according to claims 1 or 6 including a hot mirror positioned between said beam source and said array.

12. A system according to claims 1 or 6 in which at least certain of said liquid crystal pixels comprise nematic liquid crystal materials dispersed in a polymer matrix.

13. A system according to claims 1 or 6 including a folded optical system to reverse the direction of said beam.

14. A system according to claims 1 or 6 in which said heat control means includes a liquid circulations system.

15. A system according to claims 1 or 6 in which said liquid crystal pixels comprise liquid crystal material selected from the group comprising polymer dispersed liquid crystals, nematic curvilinear aligned phase liquid crystals, liquid crystal polymer composites, and polymer network liquid crystals.

16. A system according to claims 1 or 6 in which said heat control system does not depend on forced air circulation whereby silent operation is achieved.

17. A system according to claims 1 or 6 including a programmable gobo control system for imposing additional modulation of said beam.

18. A system according to claims 1 or 6 in which the transparency of said liquid crystal pixels can be adjusted over a range of values to provide gray scale effects.

19. A system according to claims 1 or 6 including:

(1) a carrier for supporting a plurality of gobos;

(2) means for controlling said carrier to position one of said gobos in said beam; and

(3) means for varying the angular orientation, velocity, and direction of a selected gobo, whereby the generated beam pattern can be adjusted by both gobo pattern selection and orientation of the selected gobo.

20. A system according to claims 1 or 6 which said array includes an active matrix coupled to said source of image control signals.

6. An image projection system comprising:

(1) a high intensity light beam source for generating an unpolarized light beam;

(2) a beam modulation system including an addressable array of light scattering liquid crystal pixels in an essentially non-absorptive optical environment, said pixels being capable of assuming transparent and opaque states and positioned to modulate said unpolarized light beam;

(3) an active heat control system for protecting said array of liquid crystals from the heat generated by said beam, said heat control system including heat transfer means in a thermally conductive relationship with said array; and

(4) a source of image control signals connected to said array to control the transmission states of said pixels to thereby vary the image projected by said beam.

21. An image projection system according to claim 6 in which said active heat control system is thermostatically-controlled.

22. An image projection system according to claim 6 in which said light beam source has a power rating of about 1000 Watts.

23. An image projection system according to claim 6 in which said light beam source has a power rating greater than about 300 Watts.

24. A light projection system for lighting applications having one or more light projectors which include image forming means, said one or more projectors comprising:

(1) a light beam source for generating a beam having an intensity suitable for lighting applications;

(2) a projection gate located to modulate said beam and having an addressable array of light scattering liquid crystal pixels in an essentially non-absorptive optical environment, said pixels being capable of assuming transparent and opaque states;

(3) a heat control system for protecting said array of liquid crystals from heat generated by said beam;

(4) a source of image control signals connected to said array to control the states of said pixels to vary the image projected by said beam;

(5) a primary color generator for filtering said beam to repetitively produce three primary colors in succession for illuminating said array; and

(6) means for controlling said liquid crystal pixels to produce video images corresponding to each of said primary colors in synchronism with the illumination of said array with said primary colors, whereby said beam is modulated with said colored video images.

25. An image projection system comprising:

(1) a high intensity light beam source for generating a beam;

(2) a beam modulation system including an addressable array of light scattering liquid crystal pixels capable of assuming transparent and opaque states and positioned to modulate unpolarized light transmitted in said beam;

(3) a heat control system for protecting said array including a heat sink in thermally conductive relationship with said array;

(4) a source of image control signals connected to said array to control the states of said pixels to thereby vary the image projected by said beam;

(5) a primary color generator for filtering said beam to repetitively produce three primary colors in succession for illuminating said array; and

(6) means for controlling said liquid crystal pixels to produce video images corresponding to each of said primary colors in synchronism with the illumination of said array with said primary colors, whereby said beam is modulated with said colored video images.

26. A light projection system for lighting applications having one or more light projectors which include image forming means, said one or more projectors comprising:

(1) a light beam source for generating a beam having an intensity suitable for lighting applications;

(2) a projection gate located to modulate said beam and having an addressable array of light scattering liquid crystal pixels in an essentially non-absorptive optical environment, said pixels being capable of assuming transparent and opaque states;

(3) a heat control system for protecting said array of liquid crystals from heat generated by said beam;

(4) a source of image control signals connected to said array to control the states of said pixels to vary the image projected by said beam; and

(5) a color control system for adjusting the color of said beam, said color control system including a plurality of cooperating dichroic filter elements, each of said elements having adjustable filter characteristics capable of selective positioning in said beam.

27. An image projection system comprising:

(1) a high intensity light beam source for generating a beam;

(2) a beam modulation system including an addressable array of light scattering liquid crystal pixels capable of assuming transparent and opaque states and positioned to modulate unpolarized light transmitted in said beam;

(3) a heat control system for protecting said array including a heat sink in thermally conductive relationship with said array;

(4) a source of image control signals connected to said array to control the states of said pixels to thereby vary the image projected by said beam; and

(5) a color control system for adjusting the color of said beam, said color control system including a plurality of cooperating dichroic filter elements, each of said elements having adjustable filter characteristics capable of selective positioning in said beam.

28. A light projection system for lighting applications having one or more light projectors which include image forming means, said one or more projectors comprising:

(1) a light beam source for generating a beam having an intensity suitable for lighting applications;

(2) a projection gate located to modulate said beam and having an addressable array of light scattering liquid crystal pixels in an essentially non-absorptive optical environment, said pixels being capable of assuming transparent and opaque states;

(3) a heat control system for protecting said array of liquid crystals from heat generated by said beam, said heat control system including a liquid cell having a flexible membrane separating a sealed inner chamber from an outer chamber through which fluid coolant is circulated; and

(4) a source of image control signals connected to said array to control the states of said pixels to vary the image projected by said beam.

29. An image projection system comprising:

(1) a high intensity light beam source for generating a beam;

(2) a beam modulation system including an addressable array of light scattering liquid crystal pixels capable of assuming transparent and opaque states and positioned to modulate unpolarized light transmitted in said beam;

(3) a heat control system for protecting said array including a liquid cell having a flexible membrane separating a sealed inner chamber from an outer chamber through which fluid coolant is circulated; and

(4) a source of image control signals connected to said array to control the states of said pixels to thereby vary the image projected by said beam.

30. A light projection system for lighting applications having one or more light projectors which include image forming means, said one or more projectors comprising:

(1) a light beam source for generating an unpolarized light beam having an intensity suitable for lighting applications;

(2) a projection gate located to modulate said unpolarized light beam and having an addressable array of light scattering liquid crystal pixels in an essentially non-absorptive optical environment, said pixels being capable of assuming transparent and opaque states;

(3) a lamp enclosure for containing said light beam source and projection gate;

(4) a heat control system for protecting said array of liquid crystals from heat generated by said beam, said heat control system including a liquid cell in thermal contact with said array of liquid crystals, said liquid cell containing fluid coolant;

(5) a source of image control signals connected to said array to control the states of said pixels to vary the image projected by said beam; and

(6) a liquid circulation system for circulating said fluid coolant between said liquid cell and a radiator having a portion extending outside of said lamp enclosure for transferring said heat outside of said lamp enclosure.

31. A light projection system for lighting applications having one or more light projectors which include image forming means, said one or more projectors comprising:

(1) a light beam source for generating an unpolarized light beam having an intensity suitable for lighting applications;

(2) a housing for enclosing said light beam source, said housing having a light opening for allowing the projection of said light beam;

(3) a color control system for adjusting the color of said beam;

(4) a projection gate interposed between said color control system and said light opening, said projection gate modulating said unpolarized colored light beam and having an addressable array of monochromic light scattering liquid crystal pixels in an essentially non-absorptive optical environment, said pixels being capable of assuming transparent and opaque states;

(5) a heat control system for protecting said array of liquid crystals from heat generated by said beam; and

(6) a source of image control signals connected to said array to control the states of said pixels to vary the image projected by said beam.

32. The light projection system according to claim 31 in which said color control system includes a plurality of cooperating dichroic filter elements, each of said elements having adjustable filter characteristics capable of selective positioning in said beam.