Display medium using emitting particles dispersed in a transparent host

• US 6,327,074 B1
• Filed: 11/24/1999
• Issued: 12/04/2001
• Est. Priority Date: 11/25/1998
• Status: Expired due to Term

• Current Assignee: University of Central Florida Research Foundation Inc. (State University System of Florida)
• Original Assignee: University of Central Florida (State University System of Florida)
• Inventors: Bass, Michael, Jennsen, Hans
• Primary Examiner(s): Lee, John D.
• Application Number:
  US09/448,657
• Time in Patent Office: 741 Days
• Field of Search: 359/326-332, 365/151, 501/40, 501/50, 501/64, 501/78, 501/101, 501/123, 501/126, 501/152, 501/900, 501/904-906, 372/6, 372/39-42
• US Class Current: 359/326
• CPC Class Codes: C09K 11/02 Use of particular materials as binders, particle coatings or suspension media therefor
• CPC Class Codes: C09K 11/7773 with alkali or alkaline earth metal
• CPC Class Codes: G02F 2/02 Frequency-changing of light, e.g. by quantum counters
• CPC Class Codes: G09F 13/20 with luminescent surfaces or parts luminescent compositions C09K11/00; light sources using luminescence F21K2/00
• CPC Class Codes: H04N 13/324 Colour aspects
• CPC Class Codes: H04N 13/39 the picture elements emitting light at places where a pair of light beams intersect in a transparent material

Abstract

Two and three dimensional color image displays. The displays include a display medium having a substantially uniform dispersion of red, green and blue visible light emitting particles sized between approximately 0.5 to approximately 50 microns therethrough. The particles can be dye doped polymethylmethacrylate(pmma) plastic, and the display medium can be pmma, acrylic plastic or glass. Other particles can be used such as rare earth doped crystals. The two dimensional display uses three laser sources each having different wavelengths that direct light beams to each of three different types of particle in the display medium. Light is absorbed by the particles which then become excited and emit visible fluorescence. Modulators, scanners and lens can be used to move and focus the laser beams to different pixels in order to form the two dimensional images having different visible colors.

Claims

1. A method of displaying two dimensional color images, comprising the steps of:

generating a first light beam having a first wavelength to excite first particles located in a transparent display medium, the first particles include sodium yttrium fluoride(NaYF4) doped with rare earth family emitting ions;

generating a second light beam having a second wavelength to excite second particles in the transparent display medium, the first wavelength being different than the second wavelength, the first particles being different from the second particles;

absorbing the first light beam in the first particles located in the transparent display medium;

absorbing the second light beam in the second particles in the transparent display medium;

forming a first visible light color from the first particles being excited by the first light beam;

forming a second visible light color from the second particles being excited by the second light beam, the first visible color being different from the second visible color; and

moving the first light beam and the second light beam to excite different particles in different places in the display medium to form the two dimensional image in two colors.

2. The method of displaying two dimensional color images of claim 1, wherein the first light beam and the second light beam are generated from:

a laser diode source.

3. The method of displaying two dimensional color images of claim 1, wherein the first particles and the second particles include:

dye doped plastic.

4. The method of displaying two dimensional color images of claim 3, wherein the plastic includes:

polymethylmethacrylate(pmma).

5. The method of claim 3, wherein the dye doped plastics includes:

a dye having a large Stokes shift, narrow absorption band, high coefficient of nonlinear aborption and high quantum efficiency.

6. The method of displaying two dimensional color images of claim 1, wherein the first particles and the second particles include:

sizes of approximately 0.5 microns to approximately 50 microns each.

7. The method of displaying two dimensional color images of claim 1, wherein the rare earth family emitting ions are chosen from at least one of:

Br(erbium), Tm(thulium), Ho(holmium) and Pr(praesodymium).

8. The method of displaying two dimensional color images of claim 1, wherein the display medium includes at least one of:

polymethylmethacrylate(pmma), acrylic plastic and glass.

9. The method of displaying two dimensional color images of claim 1, wherein the first particles and the second particles are substantially uniformly dispersed in the display medium.

10. A method of displaying three dimensional color images, comprising the steps of:

generating a first light beam having a first wavelength to first particles located in a transparent display medium, the first particles including sodium yttrium fluoride(NaYF4) doped with rare earth family emitting ions;

generating a second light beam having a second wavelength to the first particles, the first wavelength being different from the second wavelength;

intersecting the first beam with the second beam to excite a first visible color;

generating a third light beam having a third wavelength to second particles located in the transparent display medium, the second particles being different from the first particles;

generating a fourth light beam having a fourth wavelength to the second particles, the third wavelength being different from the fourth wavelength;

intersecting the third beam with the fourth beam to excite a second visible color which is different from the first visible color; and

moving the intersecting beams to form a three dimensional image having two colors.

11. The method of displaying three dimensional images of claim 10, wherein the first particles and the second particles include:

dye doped plastic.

12. The method of displaying three dimensional color images of claim 11, wherein the plastic includes:

polymethylmethacrylate(pmma).

13. The method of displaying three dimensional color images of claim 10, wherein the first particles and the second particles each include:

sizes of approximately 0.5 microns to approximately 50 microns each.

14. The method of displaying three dimensional color images of claim 10, wherein the rare earth family emitting ions are chosen from at least one of:

Er(erbium), Tm(thulium), Ho(holmium) and Pr(praesodymium).

15. A method of displaying two dimensional color images, comprising the steps of:

generating a first light beam having a first wavelength to excite first particles located in a transparent display medium, the first particles include dye doped plastics;

generating a second light beam having a second wavelength to excite second particles in the transparent display medium, the first wavelength being different than the second wavelength, the first particles being different from the second particles;

absorbing the first light beam in the first particles located in the transparent display medium;

absorbing the second light beam in the second particles in the transparent display medium;

forming a first visible light color from the first particles being excited by the first light beam;

forming a second visible light color from the second particles being excited by the second light beam, the first visible color being different from the second visible color; and

moving the first light beam and the second light beam to excite different particles in different places in the display medium to form the two dimensional image in two colors.

16. The method of claim 15, wherein the dye doped plastics includes:

polymethylmethacrylate(pmma).

17. The method of claim 15, wherein the dye doped plastics includes:

a dye having a large Stokes shift, narrow absorption band, high coefficient of nonlinear absorption and high quantum efficiency.

18. A method of displaying three dimensional color images, comprising the steps of:

generating a first light beam having a first wavelength to first particles located in a transparent display medium, the first particles including dye doped plastics;

generating a second light beam having a second wavelength to the first particles, the first wavelength being different from the second wavelength;

intersecting the first beam with the second beam to excite a first visible color;

generating a third light beam having a third wavelength to second particles located in the transparent display medium, the second particles being different from the first particles;

generating a fourth light beam having a fourth wavelength to the second particles, the third wavelength being different from the fourth wavelength;

intersecting the third beam with the fourth beam to excite a second visible color which is different from the first visible color; and

moving the intersecting beams to form a three dimensional image having two colors.

19. The method of claim 18, wherein the dye doped plastics includes:

polymethylmethacrylate(pmma).

20. The method of claim 18, wherein the dye doped plastics includes:

a dye having a large Stokes shift, narrow absorption band, high coefficient of nonlinear absorption and high quantum efficiency.