Accession Number : AD0787116

Title :   Effect of Filament Length on Performance of Drum Lenses,

Corporate Author : COAST GUARD BALTIMORE MD FIELD TESTING AND DEVELOPMENT CENTER

Personal Author(s) : Scharfenstein,C. F. , Jr

Report Date : 02 OCT 1957

Pagination or Media Count : 18

Abstract : The peak beam candlepower of a lens-lamp combination depends upon the size and shape of the lamp filament. This relationship can be stated in terms of the variation of lens-to-lamp candlepower ratio with lamp filament length. Previous tests showed that the lens-to-lamp ratio increases with decreasing filament length. These previous tests were made with filaments having lengths from about 6 millimeters to 3.6 millimeters. In this report, measurements of lens to lamp ratios are presented for filaments having lengths of from 6 millimeters to 2.5 millimeters. These measurements are given for a 200 millimeter pressed glass drum lens, 300 millimeter pressed glass closed top drum lens, and a 375 millimeter cut-glass drum lens. (Modified author abstract)

Descriptors :   *Navigational lights, *Lenses, Filaments, Sizes(Dimensions), Glass

Subject Categories : Marine Engineering

Distribution Statement : APPROVED FOR PUBLIC RELEASE