Some Problems in the Design of High Output Fluorescent Lamps Part 1

Abstract

The effects of bulb diameter on the electrical characteristics and luminous efficiency of fluorescent lamps have been studied in some reports. Most of these studies, however, were made under different conditions with lamps of different diameters; for example the filled gas pressures are not the same in one case, the bulb wall temperatures are different in another case. Concerning the bulbs of much higher input, these kinds of reports are very rare and more incomplete. Here are made some discussions of this problem, from several points of view, on the results of experiments which have been made under the same conditions with lamps of several different bulb diameters.As a basis of discussions, the brightness distribution changes of fluorescent lamps depending on bulb diameters are treated in this report.1. On some assumptions and applying the experimental results, the equation of brightness distribution is obtained from the soluton of integral equatin expressing the illumination on the inner surface of bulb. The calculating results of this brightness distribution show goodconcurrence with experimental brightness distribution.2. Relations between center brightness and total luminous flux, derived from the above brightness equation, are shown with some calculating results for several lamp dimensions, revealing that even when the luminous flux per unit length at the center portion of the bulb is just the same, the total flux is not the same depending on the bulb diameter.