
The automotive industry has developed several high sensitivity CFAs, such as RCCB, RCCG and RYYCy, by substituting the primary color filters in the standard Bayer color filter pattern with lighter colors. This has had the side effect of lowering color accuracy, and more importantly, color separation of important traffic features such as traffic lights and lane markers. All high sensitivity automotive CFAs retain the red filter given the importance of red lights and signs. Counter-intuitively, this is a sub-optimal strategy, since the ideal red spectral response, being a difference of two Gaussians, has a large negative lobe that cannot be accurately approximated by a color filter. A more accurate method of capturing red is as a difference of yellow and green, which is analogous to the difference of L and M retinal cones that the human visual system uses. Remarkably, this results in both an improvement of sensitivity and color accuracy instead of trading off one for the other.