| 摘要 |
PURPOSE:To realize fast reading with a few amount of power consumption, by using jointly a halogen lamp and a fluorescent lamp in the luminaire of an image reader with a color separation function. CONSTITUTION:In the spectral distribution of the halogen lamp 3, a large amount of R component, a medium amount of G component, and a small amount of B component exist. Therefore, as the halogen lamp 3, the halogen lamp whose light quantity can secure the upper limit value of the reference voltage of the G component up to around the saturation voltage of a CCD sensor chip 8 is used. And the halogen lamp 3 and a blue fluorescent lamp 6 are lit simultaneously, and the power consumption and an illumination position are decided so that the upper limit value of the reference voltage of the B component can be set almost equal to that of the reference voltages of the G and the R components. In such a way, the upper limit values of the reference voltages of the R, the G, and the B components can be set almost equal to each other, and it is possible to suppress the correction of color balance at a minimum level, and also, to suppress the cut of light flux due to a filter at minimum, and to reduce the power consumption.
|
