Dye-based filter

• US 7,081,991 B2
• Filed: 03/14/2003
• Issued: 07/25/2006
• Est. Priority Date: 03/14/2003
• Status: Active Grant

• Current Assignee: Rockwell Collins, Inc. (Rtx Corporation)
• Original Assignee: Rockwell Collins, Inc. (Rtx Corporation)
• Inventors: Johnson, Ricky J., Sampica, James D., Jones, Michael R., Ryang, Hong-Son, Warren, Leslie F. Jr., Stuppi, Albert N.
• Primary Examiner(s): Lavarias, Arnel C.
• Application Number:
  US10/390,543
• Publication Number:
  US 20040179283A1
• Time in Patent Office: 1,229 Days
• Field of Search: 359/361, 359/350, 359/352, 359/353, 359/359, 359/885, 359/887, 359/888, 359/889, 359/890, 359/891, 359/892, 362/19, 362/242, 362/248, 362/311, 362/351, 362/800, 252/587
• US Class Current: 359/359
• CPC Class Codes: G02B 5/208 for use with infrared or ultraviolet radiation, e.g. for separating visible light from infrared and/or ultraviolet radiation
• CPC Class Codes: G02B 5/223 containing organic substances, e.g. dyes, inks or pigments
• CPC Class Codes: G02F 1/133509 Filters, e.g. light shielding masks
• CPC Class Codes: Y10S 362/80 Light emitting diode

Abstract

A display includes a light source. The display also includes a filter positioned to receive light from the light source. The filter is a dye-based filter and attenuates light in the infrared range. The filter can be configured to have a very sharp spectral cutoff. The filter can be an NVIS filter. The display can be utilized in an avionic display system with night vision equipment. The filter can include a host polymer doped with a dye including cobalt or nickel.

Claims

1. A display including a light source, the display comprising a dye-based filter material positioned to receive light from the light source, wherein the dye-based filter material absorbs light in the infrared range with respect to light in the visible range, the dye-based filter material having a sharp cutoff between 600 and 640 nm, wherein the dye-based filter material includes at least one salt of MX₄²⁻

types where M is Co or Ni.

2. The display of claim 1, wherein the dye-based filter material provides night vision imagine system (NVIS) filtering.

3. The display of claim 2, wherein X is a halide.

4. The display of claim 3, wherein the dye-based filter material is mixed with a polymer.

5. The display of claim 1, further comprising:

a plurality of light-emitting diodes serving as the light source.

6. The display of claim 5, wherein at least one of the plurality of light-emitting diodes is coated with the dye-based filter material.

7. The display of claim 6, wherein the plurality of light emitting diodes are arranged in an array and a pattern within the may of light emitting diodes is coated with the dye-based filter material.

8. The display of claim 5, wherein at least one of the light emitting diodes has a lens formed with dye-based material mixed with polymer.

10. The avionic display system of claim 8, wherein the light source includes light emitting diodes and the dye-based filter material is coated on the light emitting diodes.

9. An avionic display system, comprising:

a display configured to provide visual images in the visual frequency range; and

a dye-based filter material positioned to receive light associated with the visual images, the dye-based filter material attenuating light in the near-infrared and infrared range, wherein the dye base filter material includes at least one salt of MX₄² where X is a halide and M is a metal.

11. The system of claim 9, wherein the dye-based filter material is a copper or cobalt dye material.

12. The display system of claim 9, further comprising a filter for attenuating light at wavelengths above 750 nm.

13. A method of manufacturing a display, the method comprising:

providing a light source; and

coating the light source with a film that receives light from the light source with a dye-based filter material, wherein the dye-based filter material attenuates light in the infrared range, wherein the dye-based filter material includes a dye including a polymer host doped with combinations of at least one of CoCl₄²⁻

and CoBr₄²⁻

.

14. The method of claim 13, further comprising:

providing an overcoat to the dye material to seal from the environment.

15. The method of claim 14, wherein the dye-based filter material includes at least one methyltrioclylammonium.

16. The method of claim 14, wherein the light source is an array of light emitting diodes and at least one of the light emitting diodes is coated.

17. A display system, comprising:

means for providing a visual image; and

means for filtering light to absorb the light associated with the visual image above a selected wavelength range, wherein the selected wavelength range is above 610 nm, wherein the means for filtering includes a member of the family of tetrahedrally-coordinated metal ions of d⁷ cobalt (2+) and d⁸ nickel (2+), where d signifies the electron configurations of divalent (2+) metal ions.

18. A night vision imaging system NVIS filter, comprising:

a monomer or polymer host; and

a dye, the host being doped with the dye, the filter absorbing light in the near-infrared and infrared range and allowing light in the visible range to pass, wherein the filter includes a member of the family of tetrahedrally-coordinated metal ions of d⁷ cobalt (2+) and d⁸ nickel (2+), where d signifies the three electron configurations of divalent (2+) metal ions.

19. The filter of claim 18, wherein the filter attenuates light between a wavelength of 640 nm and 740 nm to a level below 10%.

20. The filter of claim 18 further comprising:

a pair of translucent films, wherein at least one of the translucent films are polarized.

21. The filter of claim 18 further comprising:

a blocking filter providing attenuation in the range of 745 nm to 1000 nm.