| 摘要 |
PURPOSE:To reduce the decrease in the luminous flux of a fluorescent lamp while making the tube diameter of the lamp small, and thereby increase the life of the lamp by restricting both the permeability by straight light and density of a phosphor coating formed over the glass tube of the lamp. CONSTITUTION:The inner wall of a glass bulb with an inner diameter of 24-29mm. is coated with a phosphor with a permeability by straight light of 31-38%, so that the density of the phoshor is 5.0-11.0mg/cm<2>. For the purpose of obtaining a fluorescent lamp of a higher efficiency, spherical or cubic phosphors having an optimum permeability should be applied to the inner wall of the glass bulb. |
