Cause of red pupils
WHY do some people's pupils appear red-orange when they have their picture taken with a flash? The reddish-orange dot you see in people's eyes in photographs is light reflected from the flash off the surface of the retina, says Dr Carmen Puliafito, chairman of the ophthalmology department at the Tufts University School of Medicine in the United States.
The retina, a thin film-like layer of tissue lining the inside of the eye, is transparent, but just behind it is a layer of orange-brown tissue. The light reflects from this layer.