けい光放電管の相互反射と輝き分布
1968 年 52 巻 8 号 p. 468-477
詳細
1968 年 52 巻 8 号 p. 468-477
The author tries to obtain the brightness distribution curve of a fluorescent lamp more easily by solving matrices of interreflection derived by Prof. O' Brien by means of a computer.
First of all, he divides a 20 watts fluorescent lamp into 20 parts and measures their brightness to take the ratios of them to that of the central part. And also he measures transmittances and reflectances of phosphors and a glass, radiation of ultraviolet and visible mercury rays.
Then getting shape factors between divided parts of a tube, he forms the matrices, and tries to coincide the calculated results with the measured ones changing the values of matrices, especially of the initial luminous radiances.
After many trials, he finds that inside the fluorescent lamp, ultraviolet rays interreflect with the reflectance factor about 0.7 and the consequent radiant flux density is quite high.
Next, he derives a following formula which contains the transmittance of the phosphor and the glassy and verifies it practically.
Li·out=τg [Loi·out+τpΣmj=1F (i, j) Lj·in]
