Sigma have re-engineered their DP APSC compacts with new angular body design, and 45mm fixed lens. The main attraction is the redeveloped Foveon sensor. I won’t bore you with technical explanations, but this very technical response reply to the post about the new Sigma camera on dpreview.com mentioned the word photon a few times, which caught my Photonbox eye! Star Trek fans will understand all this perfectly…
We have to go back to Physics 101 classroom
Photon can be both wave and particle at the same time.
The three layers sensor is doped with different elements. The final result is the uppermost P-N junction requires high energy photon to kick the electron (or hole) out of the orbit, generates electrical current.
After photons travel pass through, the high energy photon will be absorbed completely by this high-exitation P-N.
This ‘absorption’ is occured at the middle GREEN and lower RED layers, too.
Because of the wave/particle property, you may think that the “YELLOW” photon is really composed of RED and GREEN photon pairs.
Green will be absorbed in green. Red will be absorbed in red, and the same vertical axis.
After that – you just calculate what is the true color of that pixel, given signal strength from GREEN and RED layer.