FLUORESCENT LAMP

摘要

PURPOSE:To assure high color rendering characteristic without lowering lamp efficiency by adding at least one light emission property of those near 520nm and 620nm to the three wavelength light emission type fluorescent lamp. CONSTITUTION:A kind of phosphor material which shows the maximum light emitting wavelength at 490-530nm and phosphor material which shows the maximum light emitting wavelength at 620-660nm is added to a mixture consisting of a rare earth oxide phosphor material which is activated by tervalent europium and has the maximum light emitting wavelength in the range of wavelength of 600-620nm, a phosphor material which has the maximum light emitting wavelength in the range of 530-580nm and shows light emission of tervalent terbium and a phosphor material which has the maximum light emission wavelength in the range of 460-490nm and shows light emission of bivalent europium or tervalent antimony. The internal wall of bulb is coated with such mixture and the fluorescent lamp is thus formed. Therefore, a practical fluorescent lamp having satisfactory solor rendering characteristic and high lamp efficiency can be obtained.