04306769 is referenced by 40 patents and cites 11 patents.

An apparatus for collecting sunlight and directing the collected sunlight into the interior of the building to provide illumination, so that the energy used for artificial illumination can be conserved, includes a collector, a light pipe, and a diffuser. The collector includes an immovable flared trumpet-like hollow tube having a highly reflective interior surface and having its larger aperture oriented to maximize the sunlight received at a particular time of day. The larger aperture is closed by a transparent cap which supports a secondary reflector that extends forward of the larger aperture. The secondary reflector serves to reflect into the hollow tube light travelling at a low angle of incidence with respect to the larger aperture to compensate for the reduced efficiency of the larger aperture to low-angle light. The apparatus also includes a sprinkler for washing dust and other deposits from the transparent cap, and further includes a servo-controlled light valve for maintaining, to the extent possible, a constant level of illumination at a work station within the building.

Title
Interior illumination apparatus using sunlight
Application Number
6/138539
Publication Number
4306769
Application Date
April 9, 1980
Publication Date
December 22, 1981
Inventor
Michael E Martinet
10315 Hester Ave., Whittier, 90603
CA, US
Agent
Smyth Pavitt Siegemund & Martella
IPC
B02B 17/00
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