| 摘要 |
PURPOSE: To reduce instability of light quantity and also to shorten the warm-up time immediately after the turn-on of power by providing two kinds of thermal insulation sequences for raising and maintaining the temperature of two fluorescent lamps and changing the thermal insulation sequence when either of the lamps is warm. CONSTITUTION: The device is composed from a fluorescent lamp 101 in use for reflection-type documents, a fluorescence tube 102 in use for transparent-type documents, a light quantity sensor 103 which detects the light quantity of the fluorescent lamp 101, and a control section 104 which controls lighting of the fluorescent lamps 101, 102. The control section 104 has at least two kinds of thermal insulation sequences for raising and maintaining the temperatures of the fluorescent lamps, 101, 102. When either tube is raised in temperature, the thermal insulation sequence for raising temperature is changed to that for temperature retention. |
