Chromatic Aberration
Stereoptic depth perception obtained from two dimensional red and blue or red and green images is believed to be caused primarily by optical chromatic aberrations. Chromatic aberrations are defined as types of optical distortions that occur as a consequence of refracting properties of the eye. However, other factors, image characteristics, and perceptual factors also play a role in color depth effects under natural viewing conditions. Additionally, texture properties of the stimulus can also play a role.
Newton first demonstrated the presence of chromatic aberration in the human eye in 1670. He observed that isolated incident light rays directed at an opaque card held close to the eye strike the refracting surfaces of the eye obliquely and are therefore strongly refracted. Because the indices of refraction (see: Refractive Index) vary inversely with wavelength, blue rays (short wavelength) will be refracted more than red rays (long wavelength). This phenomenon is called chromatic dispersion and has important implications for the optical performance of the eye, including the stereoptic effect. For instance, Newton noted that such chromatic dispersion causes the edges of a white object to be tinged with color.
Modern accounts of chromatic aberrations divide ocular chromatic aberrations into two main categories; longitudinal chromatic aberration (LCA), and transverse chromatic aberration (TCA).
Read more about this topic: Chromostereopsis
Famous quotes containing the word aberration:
“The era of the political was one of anomie: crisis, violence, madness and revolution. The era of the transpolitical is that of anomaly: an aberration of no consequence, contemporaneous with the event of no consequence.”
—Jean Baudrillard (b. 1929)