THE 100 MOST INFLUENTIAL INVENTORS OF ALL TIME

7 The 100 Most Influential Inventors of All Time 7

used, three-dimensional motion-picture process based on
polarized light. During World War II he applied the polar-
izing principle to various types of military equipment.
Land began work on an instantaneous developing
film after the war. In 1947 he demonstrated a camera
(known as the Polaroid Land Camera) that produced a
finished print in 60 seconds. The Land photographic
process soon found numerous commercial, military, and
scientific applications. Many innovations were made in
the following years, including the development of a colour
process. Land’s Polaroid Land cameras, which were able
to produce developed photographs within one minute
after the exposure, became some of the most popular
cameras in the world.
Land’s interest in light and colour resulted in a new
theory of colour perception. In a series of experiments he
revealed certain conflicts in the classical theory of colour
perception. He found that the colour perceived is not
dependent on the relative amounts of blue, green, and
red light entering the eye; he proposed that at least three
independent image-forming mechanisms, which he called
retinexes, are sensitive to different colours and work in
conjunction to indicate the colour seen.
Land received more than 500 patents for his innova-
tions in light and plastics. In 1980 he retired as chief
executive officer of Polaroid but remained active in the field
of light and colour research by working with the Rowland
Institute of Science, a nonprofit centre supported by the
Rowland Foundation, Inc., a corporation that Land
founded in 1960. Under Land’s direction, Rowland
researchers discovered that perception of light and colour
is regulated essentially by the brain, rather than through a
spectrum system in the retina of the eye, as was previously
believed.