| 摘要 |
PROBLEM TO BE SOLVED: To enable to preheat quickly and to emit stable light at the same time. SOLUTION: Pins for an application-specific IC (ASIC) of a scanner are used to output different frequency pulses. A power supply unit in the scanner outputs two kinds of frequencies which are a frequency (30 kHz) required at a preheating time, and a frequency (60 kHz) required at a normal operation. The lighting fixture used takes on different illumination intensities in different frequencies. A low-efficiency frequency (30 kHz) is supplied to the lighting fixture to preheat quickly. Since the illumination intensity efficiency is comparatively low at this frequency, heat is generated from the lighting fixture, but this heat is actively used for preheating. After preheating, a frequency of the highest illumination intensity efficiency (60 kHz) is supplied to the lighting fixture. COPYRIGHT: (C)2003,JPO |
