Regulating a light source using a light-to-frequency converter

1. An apparatus comprising:

a light source;

a light guide between the light source and a display, the light guide arranged to channel and reflect the light from the light source;

a light-to-frequency converter that converts light received from said light source into a signal having a corresponding frequency; and

a circuit coupled to said light-to-frequency converter, said circuit comprising a frequency scaler coupled between said light-to-frequency converter and a frequency counter, said frequency counter for determining the frequency of the signal, said frequency scaler for adjusting the frequency of the signal to within a range of the frequency counter, said circuit configured to regulate light emitted from said light source over the life of the display, wherein the light-to-frequency converter and the circuit are implemented on a single integrated circuit die.

2. The apparatus of claim 1 wherein said circuit regulates the brightness of said light.

3. The apparatus of claim 1 wherein said circuit controls a color produced by said light source.

4. The apparatus of claim 1 wherein said circuit comprises a signal processor, said signal processor using said frequency of said signal to determine whether to adjust said light source.

5. The apparatus of claim 1 further comprising a pulse width modulator generator that drives said light source.

6. The apparatus of claim 1 wherein said light source is used to back-light a display.

7. The apparatus of claim 1 wherein said circuit regulates light emitted from said light source by adjusting a second signal that drives the light source.

8. The apparatus of claim 7 wherein said second signal controls the color of light produced by said light source.

9. The apparatus of claim 7 wherein said second signal drives the intensity of light emitted from said light source.