Illumination Sources and Customizable Spectral Profiles

• US 20100085563A1
• Filed: 10/23/2009
• Published: 04/08/2010
• Est. Priority Date: 09/22/2004
• Status: Active Grant

• 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.
• Granted Patent: US 7,929,130 B2
• Time in Patent Office: Days
• US Class Current: 356/300
• CPC Class Codes: G01J 2001/0276 Protection
• CPC Class Codes: G01J 2003/1282 Spectrum tailoring
• CPC Class Codes: G01J 3/10 Arrangements of light sources specially adapted for spectrometry or colorimetry
• CPC Class Codes: G01J 3/46 Measurement of colour; Colour measuring devices, e.g. colorimeters measuring colour temperature G01J5/60
• CPC Class Codes: G01J 3/462 Computing operations in or between colour spaces; Colour management systems
• CPC Class Codes: G01J 3/465 taking into account the colour perception of the eye; using tristimulus detection
• CPC Class Codes: G02B 27/0012 Optical design, e.g. procedures, algorithms, optimisation routines

Abstract

Methods for generating a customized spectral profile, which can be used to generate a corresponding filter, lamp or other type of illuminant. A trial spectrum can be generated. A reference spectrum can be determined or otherwise obtained. A SOURCE spectrum can be determined or otherwise obtained. One or more optical indices can be calculated using the trial spectrum and one or more of the optical indices are optimized by varying the trial spectrum to generate the customized spectral profile. A radiation force parameter can be used to minimize unsafe build-up of light in spectral regions. Adaptations of color rendering parameters can be used in the optimization process. Smoothing parameters can be used to enable easier design of filter structures. A reflectance camera can be used to measure reflectance data at one or more pixels of a digital representation of an object to be illuminated.

Claims

1. A method for generating a customized spectral profile, comprising:

generating a trial spectrum;

obtaining a reference spectrum;

calculating one or more optical indices of the trial spectrum from measured spectral data of an object;

calculating one or more corresponding optical indices of the reference spectrum; and

varying the trial spectrum with a computer to optimize the one or more optical indices of the trial spectrum with respect to the one or more corresponding optical indices of the reference spectrum to generate the customized spectral profile.

2. The method of claim 1, the measured spectral data comprising data from an image of the object.

3. The method of claim 1, the measured spectral data comprising reflectance spectra of an object.

4. The method of claim 3, the measured spectral data comprising reflectance spectra from a plurality of pixels of a digital representation of the object.

5. The method of claim 1, the optical indices comprising one or more of chromaticity, filter efficiency, lumens per watt efficiency, overall filter efficiency, watt reduction criteria, radiation force, profile smoothing, color rendering index, and modified color rendering index.

6. The method of claim 5, one or more of the optical indices corresponding to a specific object to be illuminated.

7. The method of claim 6, the specific object comprising a work of art.

8. The method of claim 1, the varying comprising varying the trial spectrum by changing one or more parameters of contributing functions of the trial spectrum or changing individual values of the trial spectrum at different wavelengths.

9. The method of claim 1, the spectral profile rendering only photometric light, or tailored regions of photometric light.

10. The method of claim 1, the spectral profile comprising a spectral profile for aesthetically rendering an object.

11. The method of claim 10, the spectral profile being selected from the group consisting of a candlelight profile, a torchlight profile, a fluorescent profile, an incandescent profile, a halogen profile, an oil lamp profile, a daylight profile, a roomlight profile, a gas light, a lime light profile, and a mantle-light profile.

12. The method of claim 10, the spectral profile comprising an emphasis profile for emphasizing one or more colors of the object or to affect a perceived color contrast of the object.

13. The method of claim 1, the customized spectral profile comprising a spectral profile for correcting the rendering of an object.

14. The method of claim 13, the spectral profile comprising a profile for correcting the rendering of the object for an eye experiencing loss of vision with respect to one or more colors.

15. A method for generating an optical filter, lamp, or other illuminant comprising generating an optical filter, lamp, or other illuminant from a customized spectral profile, the customized spectral profile being generated by optimizing one or more optical indices of a trial spectrum calculated from measured spectral data of an object, the optimization comprising varying the trial spectrum with respect to one or more corresponding optical indices of a reference spectrum.

16. Computer-readable media comprising instructions for:

generating a trial spectrum;

obtaining a reference spectrum;

calculating one or more optical indices of the trial spectrum;

calculating one or more corresponding optical indices of a reference spectrum; and

varying the trial spectrum to optimize the one or more optical indices of the trial spectrum with respect to the one or more corresponding optical indices of the reference spectrum to generate the customized spectral profile.

17. The computer-readable media of claim 16, further comprising instructions for:

calculating one or more optical indices of a SOURCE spectrum; and

varying the trial spectrum to optimize the one or more optical indices of the trial spectrum with respect to the one or more corresponding optical indices of the SOURCE spectrum to generate the customized spectral profile.