Protective Light Filters Having Customized Spectral Profiles

• US 20110019269A1
• Filed: 07/21/2010
• Published: 01/27/2011
• Est. Priority Date: 07/21/2009
• Status: Abandoned Application

• Current Assignee: Board of Regents of the University of Texas System (University of Texas System)
• Original Assignee: Board of Regents of the University of Texas System (University of Texas System)
• Inventors: Dirk, Carl W.
• Application Number:
  US12/840,891
• Publication Number:
  US 20110019269A1
• Time in Patent Office: Days
• US Class Current: 359/359
• CPC Class Codes: G02B 27/0012 Optical design, e.g. procedures, algorithms, optimisation routines
• CPC Class Codes: G02B 5/205 Neutral density filters

Abstract

Optical filters (e.g., sunglass lenses and/or window-tint films) having customized spectral profiles.

Claims

1. An optical filter comprising:

a substrate;

one or more filter layers coupled to the substrate, at least one of the one or more filter layers in direct contact with the substrate;

where the optical filter is configured to reduce luminance by between about 80% and about 90% and to have a color rendering index (CRI) of more than about 80 relative to an unfiltered reference illuminant.

2. The optical filter of claim 1, where the unfiltered reference illuminant is sunlight.

3. The optical filter of claim 1, where the unfiltered reference illuminant is a Standard D65 illuminant.

4. The optical filter of claim 1, where the optical filter is configured to have a CRI of between about 85 and about 95.

5. The optical filter of claim 4, where the optical filter is configured to have a CRI of more than about 90.

6. The optical filter of claim 1, where the optical filter is configured to reduce luminance by about 85%.

7. The optical filter of claim 1, where the optical filter is configured to transmit at least some portion of light having a wavelength above about 400 nanometers (nm) and to substantially block light having a wavelength below about 400 nm.

8. The optical filter of claim 1, where the optical filter is configured to transmit at least some portion of light having a wavelength below about 750 nanometers (nm) and to substantially block light having a wavelength above about 750 nm.

9. The optical filter of claim 1, where the optical filter is configured to:

(a) block at least 95% of light having a wavelength below about 410 nanometers;

(b) block at least 95% of light having a wavelength above about 710 nm;

(c) block between about 70% and about 90% light having a wavelength between about 510 nm and about 550 nm and between about 590 nm and about 630 nm; and

(d) block less than about 20% of at least one wavelength of light having a wavelength between about 450 nm and about 470 nm.

10. The optical filter of claim 9, where the optical filter is configured to block at least 95% of at least one wavelength of light having a wavelength between about 460 nm and about 490 nm.

11. The optical filter of claim 10, where the optical filter is configured to transmit between about 20% and about 30% of at least one wavelength of light having a wavelength between about 520 nm and about 540 nm.

12. The optical filter of claim 11, where the optical filter is configured to block between about 85% and about 95% of at least one wavelength of light having a wavelength between about 560 nm and about 580 nm.

13. The optical filter of claim 12, where the optical filter is configured to transmit between about 15% and about 25% of at least one wavelength of light having a wavelength between about 600 nm and about 620 nm.

14. The optical filter of claim 1, where the optical filter is configured to be coupled to a sunglass frame.

15. The optical filter of claim 1, where the optical filter comprises a substantially rigid sheet suitable for a window.

16. A pair of sunglasses comprising:

one or more optical filters of claim 1.

17. A method of generating a customized spectral profile, comprising:

obtaining a reference spectrum for an unfiltered reference illuminant;

generating a trial spectrum;

calculating one or more optical indices of the trial spectrum;

generating a customized spectral profile by varying with a computer the trial spectrum to optimize the one or more optical indices of the trial spectrum relative to the reference spectrum.

18. The method of claim 17, where the reference spectrum comprises a Standard D65 spectral profile.

19. The method of claim 18, where the reference spectrum is the spectral profile of a an illuminant having a spectral profile substantially similar to the Standard D65 spectral profile.

20. The method of claim 17, where calculating one or more optical indices comprises calculating the reduction in luminance and the color rendering index (CRI) of the trial spectrum relative to the reference spectrum.

21. The method of claim 20, where generating a customized spectral profile comprises:

varying the trial spectrum to maximize the reduction in luminance of the trial spectrum while simultaneously maximizing the CRI of the trial spectrum.

22. The method of claim 20, where generating a customized spectral profile comprises:

selecting a target reduction in luminance of the trial spectrum; and

varying the trial spectrum to maximize the CRI of the customized trial spectrum at the target reduction in luminance.

23. The method of claim 20, where generating a customized spectral profile comprises:

selecting a target CRI of the trial spectrum; and

varying the trial spectrum to maximize the reduction in luminance of the trial spectrum at the target CRI.