light viewer
Date: circa 1959
Inventory Number: 2004-1-0284
Classification: Optics Apparatus
Subject:
Maker: Edwin H. Land (1909 - 1991)
Maker: General Electric Company (1892-present)
Cultural Region:
Place of Origin:
Dimensions:
23.5 × 19 × 24 cm (9 1/4 × 7 1/2 × 9 7/16 in.)
Description:
A trapezoid shaped box in which is found three light sources and two mirrors positioned at 45° each. Each light has its own electric cord. On one of the box's sides there is a window to examine the superposition of images produced by this apparatus.
In Collection(s)
Signedon light bulbs: GE
FunctionUsed to illuminate with different types of light (sodium, tungsten, etc.) glass plates in order to study color vision. Land used this instrument for his Retinex theory.
Curatorial RemarksThis apparatus is similar to a drawing from one of Land's 1959 articles on color vision. Though similar, it cannot be this one since, as the description goes: "In order to make the demonstration more effective we built a pair of viewers (Fig. 4), each employing a large sodium-vapor street light as one of the illuminants. In each viewer the long and short records are placed ar right angles to one another and the images are superposed, as they are in the dual monochromator, by means of a semi-mirror at 45°" (p. 641 and 644). The apparatus here was probably built for similar studies on color vision. Perhaps later, since in this apparatus we find three lights shining on two semi-mirrors.
Reproduced, slightly modified, in Land, "Experiments in Color Vision," Scientific American 200 (1959): 84-99.
Reproduced, slightly modified, in Land, "Experiments in Color Vision," Scientific American 200 (1959): 84-99.
Primary SourcesEdwin Land, "Color Vision and the Natural Image, part II," Proceedings of the National Academy of Sciences of the United States of America, 45 (April 15, 1959): 636-644.
ProvenanceThis object belonged to Edwin H. Land and came from the Rowland Institute, Harvard University. Gift of the Edwin H. Land Family.