| 摘要 |
PROBLEM TO BE SOLVED: To provide a flat illumination device in which unevenness of the quantity of light is eliminated and which is simple and inexpensive, and of which power consumption is suppressed. SOLUTION: Fluorescent light sources 44(1)-44(3) at the upper part of a case 42 have the maximum luminous quantity at the vicinity of a high temperatureθ2 and the fluorescent light sources 44(4)-44(6) at the central part have the maximum luminous quantity at the vicinity of the intermediate temperatureθ3, and the fluorescent light sources 44(7)-44(9) at the lower part have the maximum luminous quantity at the vicinity of the low temperatureθ1. The fluorescent light sources 44(1)-44(9) having different luminous quantity for temperature are selectively arranged so that the luminous quantity may become nearly equal according to the temperature distribution G1 in the case 42, thereby, the distribution of the quantity of light of the erasing light outputted by the case 42 is made uniform. COPYRIGHT: (C)2003,JPO |
