Apparatus and method for measuring color

1. A method in a spectral measurement apparatus comprising the steps of:

receiving light with a plurality of sensors, wherein each sensor generates an output signal having a frequency proportional to an intensity of light received by the sensor;

generating at least a first signal having a frequency proportional to an intensity of light received by a first sensor of a first wavelength or spectral band;

generating at least a second signal having a frequency proportional to an intensity of light received by a second sensor of a second wavelength or spectral band; and

generating at least a third signal having a frequency proportional to an intensity of light received by a third sensor of a third wavelength or spectral band;

wherein a spectral characteristic of the received light is determined based on at least the first, second and third signals;

wherein the at least first, second and third signals are coupled to a processing element and input to the processing element in parallel, wherein the spectral characteristic is determined based on measuring a frequency or period of the at least first, second and third signals;

wherein spectral data based on the determined spectral characteristic is generated by the processing element and displayed on a display device for perception by a viewer or transmitted to a data interface for transmission to an electronic device external to the spectral measurement apparatus.

2. The method of claim 1 , wherein the sensors each output one or more digital signals.

3. The method of claim 2 , wherein the one or more digital signals comprise TTL or CMOS compatible signals.

4. The method of claim 3 , wherein the one or more digital signals are coupled to a microprocessor or logic circuitry without analog-to-digital conversion.

5. The method of claim 1 , wherein the spectral characteristic is determined based on measuring a frequency of the at least first, second and third signals.

6. The method of claim 1 , wherein the spectral characteristic is determined based on measuring a period of the at least first, second and third signals.

7. The method of claim 1 , wherein the spectral measurement apparatus comprises a spectrometer.

8. The method of claim 1 , wherein the spectral measurement apparatus comprises a colorimeter.

9. The method of claim 1 , wherein light is received from an object or material via one or more fiber optics.

10. The method of claim 1 , wherein the spectral characteristic is determined based on a calibration measurement.

11. The method of claim 1 , wherein the spectral characteristic is used to determine a closest color among a set of stored colors.

12. The method of claim 1 , wherein the light is generated via a broadband light source.

13. The method of claim 1 , wherein the light is generated via a plurality of light sources of different colors.

14. The method of claim 1 , wherein the processing element determines a plurality of data values from the first, second and third signals at a predetermined timing, wherein, based on the plurality of data values determined from the first, second and third signals, a frequency or period determination is made for each of the first, second and third signals.

15. The method of claim 1 , wherein the sensors each comprise an array of photodiodes.

16. The method of claim 1 , wherein the spectral characteristic is used to determine one or more closest matches to a plurality of stored colors or shades, wherein the stored colors or shades comprise shades of one or more dental shade guide systems.

17. The method of claim 1 , wherein the processing element is coupled to a light source, wherein the light source is controlled based on a signal from the processing element.

18. A method in a spectral measurement apparatus for determining a spectral characteristic of received light comprising the steps of:

generating and supplying light of a plurality of wavelengths or spectral bands;

receiving light with a plurality of sensors, wherein each sensor generates an output signal having a frequency proportional to an intensity of light received by the sensor;

generating at least a first signal having a frequency proportional to an intensity of light received by a first sensor of a first wavelength or spectral band;

generating at least a second signal having a frequency proportional to an intensity of light received by a second sensor of a second wavelength or spectral band; and

generating at least a third signal having a frequency proportional to an intensity of light received by a third sensor of a third wavelength or spectral band;

wherein a spectral characteristic of the received light is determined based on at least the first, second and third signals;

wherein the at least first, second and third signals are coupled to a processing element and input to the processing element in parallel, wherein the spectral characteristic is determined based on measuring a frequency or period of the at least first, second and third signals;

wherein spectral data based on the determined spectral characteristic is generated by the processing element and displayed on a display device for perception by a viewer or transmitted to a data interface for transmission to an electronic device external to the spectral measurement apparatus.

19. The method of claim 18 , wherein the spectral measurement apparatus comprises a spectrometer.

20. The method of claim 18 , wherein the processing element is coupled to a light source, wherein the light source is controlled based on a signal from the processing element.