Originally Posted by Zr-1Mike00
It may have something to do with the projector lens causing the color change... But that is my best guess.
This is exactly correct. Light from a projector bends slightly as it goes around the edges of the cutoff shield resulting in a prism like effect that typically only shows a section of the visual spectrum.
A well-tuned projector will show a crisp cutoff with often a blue line at the top. The "step" should be clearly visible. This photo is from one of our Bi-xenon Modified ACA Projector headlights.
A poorer quality projector may barely show a defined cutoff and (due to the flat cutoff shield) will typically show a reddish-orange color near the center of the beam. This is the pattern from the ACA headlights' factory projector using the same 5000K 55w HID light source as the projector shown above:
Since the light is being bent both around the shield and refracted through the lens, it tends to change color compared to purely reflected light. What we typically see as headlight color when looking at the car comes from this variable.