STP545: Mechanism of Vision—A Review

    Johnston, JW
    Chevy Chase, Md.

    Pages: 15    Published: Jan 1973


    Abstract

    The human retinal image is a pattern of light and dark that differs from a picture within the central nervous system. A remarkable characteristic is the “saccade,” a very fast flicking of the eyeballs such that a new focus of the image is formed on the cone cells of the central pit every few milliseconds. The saccade is especially important to reading when the day-vision cones function. The night-vision rods do not add much to day vision but are a fourth mechanism in respect to the three kinds of cones which enable the brain to distinguish contrasts between spectral hues. Despite the infinite variety of textures and settings with which colors are often perceived, there is a limited degree of color constancy of objects under varying conditions of brightness, size, and shape.

    Keywords:

    senses, perception, visual perception, memory, surfaces, images


    Paper ID: STP34755S

    Committee/Subcommittee: E12.11

    DOI: 10.1520/STP34755S


    CrossRef ASTM International is a member of CrossRef.