Abstract
We developed a method for improving the luminous flux of fluorescent lamps. The phosphor layer in fluorescent lamps is generally not uniformly thick because the phosphor suspension is poured into a vertical glass tube. We examined the relationship between the luminous flux and uniformity of the phosphor layer thickness to determine the optical thickness. By changing the thickness ratio between the ends of the lamp from 10:6 to 10:8 we improved the luminous flux by 0.9%. Changing the ratio from 10:8 to 10: 10 improved it only 0.2%. An improved luminous flux will improve the efficiency of fluorescent lamps.