Method for matching colors by using human observer color matching functions

1. A method for matching colors comprising:

providing a first source of a first color and a second source of a second color;

measuring a first set of spectral values for first color stimuli associated with the first color with a spectral measurement device controlled by a digital processing system;

calculating a first set of tristimulus values from the first set of spectral values;

defining a first set of human observer color matching functions, the first set of human observer color matching functions being functions of the first set of tristimulus values of the first color;

calculating a first set of corrected tristimulus values from the first set of spectral values using the first set of human observer color matching functions;

measuring a second set of spectral values for second color stimuli associated with the second color with the spectral measurement device controlled by the digital processing system;

calculating a second set of tristimulus values from the second set of spectral values;

defining a second set of human observer color matching functions, the second set of human observer color matching functions being functions of the second set of tristimulus values of the second color;

calculating a second set of corrected tristimulus values from the second set of spectral values using the second set of human observer color matching functions;

determining a difference between the first set of corrected tristimulus values and the second set of corrected tristimulus values;

adjusting one of the first and the second source to reduce the difference; and

wherein the first and second set of human observer color matching functions are defined according to the equation

xyz C (λ)=α( {right arrow over (XYZ)} S ) xyz S (λ)+(1.0−α( {right arrow over (XYZ)} S )) xyz M (λ) wherein xyz M (λ)

denotes human observer functions defined by visually matching white colors, xyz s (λ) denotes human observer functions defined by visually matching saturated colors, xyz c (λ) refers to the corrected human observer function, and α({right arrow over (XYZ)} s ) is a function of saturated tristimulus values {right arrow over (XYZ)} s calculated from xyz s (λ).

2. The method of claim 1 , wherein the determining a difference is performed after converting the first and second set of the tristimulus values to a perceptually uniform color space.

3. The method of claim 2 , wherein at least one of the first source and the second source is an illumination system.

4. The method of claim 2 , wherein at least one of the first source and the second source is a reflective material viewed in an illumination system.

5. The method of claim 2 , wherein at least one of the first source and the second source is an emissive display system.

6. The method of claim 2 , wherein at least one of the first source and the second source is a digital projection system.

7. The method of claim 1 , wherein at least one of the first source and the second source is an illumination system.

8. The method of claim 1 , wherein at least one of the first source and the second source is a reflective material viewed in an illumination system.

9. The method of claim 1 , wherein at least one of the first source and the second source is an emissive display system.

10. The method of claim 1 , wherein at least one of the first source and the second source is a digital projection system.

11. The method of claim 1 , wherein the tristimulus values are the cone values LMS and the color matching functions are the cone responses l (λ) m (λ) s (λ).