Protective Light Filters and Illuminants Having Customized Spectral Profiles

• US 20100290230A1
• Filed: 05/15/2009
• Published: 11/18/2010
• Est. Priority Date: 05/15/2009
• 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:
  US12/466,589
• Publication Number:
  US 20100290230A1
• Time in Patent Office: Days
• US Class Current: 362/293
• 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

Abstract

Customized spectral profiles, and filters and illuminants having customized spectral profiles.

Claims

1. A filter comprising:

a substrate;

a plurality of first filter layers comprising a first material, one of the first filter layers in direct contact with the substrate; and

a plurality of second filter layers comprising a second material;

where at least a portion of the first filter layers and at least a portion of the second filter layers are coupled in an alternating configuration; and

where the filter is configured to have a lumens/watt efficiency of more than about 170% and a color rendering index (CRI) of more than about 90, for a source illuminant relative to an unfiltered reference illuminant.

2. The filter of claim 1, where the unfiltered reference illuminant is an incandescent lamp having a color temperature of about 3000K.

3. The filter of claim 2, where the filter is further configured to have a relative power transmission of about between about 50% and about 60%.

4. The filter of claim 3, where the filter is further configured to have a relative power transmission of between about 54% and about 56%.

5. The filter of claim 1, where at least one of the source illuminant and the unfiltered reference illuminant comprises one or more light-emitting diodes (LEDs).

6. The filter of claim 1, where:

the substrate is configured to transmit light having a wavelength above about 400 nanometers (nm) and to substantially block light having a wavelength below about 400 nm;

the first filter layers each comprise Niobium (Nb);

the second filter layers each comprises Silicone (Si); and

the filter is substantially stable at temperatures above 190 degrees Celsius.

7. The filter of claim 6, where the first filter layers each comprise Nb₂O₅.

8. The filter of claim 6, where the second filter layers each comprise SiO₂.

9. The filter of claim 8, where the first filter layers each comprise Nb₂O₅.

10. The filter of claim 9, where the substrate comprises Coming 8511 glass.

11. The filter of claim 9, where:

each of the first filter layers has a thickness between about 5 nanometers (nm) and about 500 nm; and

each of the second filter layers has a thickness of between about 5 nm and about 500 nm.

12. The filter of claim 11, where:

the plurality of first filter layers comprise ten or more first filter layers; and

the plurality of second filter layers comprise ten or more second filter layers.

13. The filter of claim 12, where:

the plurality of first filter layers comprise fifteen or more first filter layers; and

the plurality of second filter layers comprise fifteen or more second filter layers.

14. The filter of claim 1, where the filter is configured such that if light is incident on the filter from a source illuminant, the filter will:

(a) block at least 95% of light having a wavelength below about 400 nanometers;

(b) block at least 95% of light having a wavelength above about 700 nm;

(c) block less than 20% of light having a wavelength between 450 nm and 630 nm and between 530 nm and 570 nm; and

(d) block between about 25% and about 35% of at least one wavelength of light having a wavelength between about 530 nm and about 570 nm.

15. The filter of claim 14, where the filter is configured such that if light is incident on the filter from a source illuminant, the filter will block between about 25% and about 35% of at least one wavelength of light having a wavelength between about 545 nm and about 555 nm.

16. The filter of claim 15, where the unfiltered reference illuminant is an incandescent lamp having a color temperature of about 3000K, and where the filter is configured such that if light is incident on the filter from a source illuminant, the filter will block between about 25% and about 35% of light having a wavelength between about 545 nm and about 555 nm.

17. The filter of claim 1, where the filter is further configured to have a CRI of more than 95.

18. The filter of claim 1, where the filter is configured such that the filtering and mechanical properties of the filter are substantially stable through at least 200 on/off cycles in which the filter is disposed within 12 inches of an incandescent lamp, where each on/off cycle includes one hour during which the lamp is on and one hour during which the lamp is off, and where during the on portion of an on/off cycle the lamp reaches a maximum temperature of at least 180 degrees Celsius.

19. A photopic filter configured such that if light is incident on the filter from a source illuminant, the filter will block substantially all non-visible light, and will have a lumens/watt efficiency of more than about 170% and a color rendering index of more than about 90, relative to an unfiltered incandescent lamp having a color temperature of about 3000K.

20. An illuminant having a customized spectral profile, the illuminant comprising:

one or more light sources;

a plurality of first filter layers comprising a first material; and

a plurality of second filter layers comprising a second material;

where at least a portion of the first filter layers and at least a portion of the second filter layers are coupled in an alternating configuration; and

where the illuminant is configured to have a lumens/watt efficiency of more than about 170% and a color rendering index (CRI) of more than about 90, relative to an unfiltered reference illuminant that comprises an incandescent lamp having a color temperature of about 3000K.

21. The illuminant of claim 20, where the one or more light sources comprise three or more light-emitting diodes (LEDs).

22. The illuminant of claim 21, where the one or more light sources comprise more than three LEDs.

23. The illuminant of claim 20, where the one or more light sources comprise an incandescent lamp.

24. The illuminant of claim 20, where the one or more light sources comprise a substrate, and where one of the first filter layers is in direct contact with the substrate.

25. The illuminant of claim 20, where the first filter layers and second filter layers are spaced apart from the one or more light sources.