There has always been a close relationship between the sciences of optics and vision. The reason is, of course, that the ultimate consumer of the products resulting from optical transformation has traditionally been the human visual system. So it is no surprise that names like Newton, Thomas Young, Brewster, Airy, Helmholtz, and Rayleigh loom as large in the history of vision as they do in the history of optics. After all, the natural history of optical phenomena would include the properties of the final detector, which until relatively recently was always the human eye.
by Gerald Westheimer