| abstract |
Since amounts of illuminated light of each color are well-balanced by using a light source generating a small amount of heat and emitting light of a high color temperature during light emission, images can be read at high speed and with high accuracy. LED chips are applied for a light source, and are arranged by color so as to form substantially straight lines on an aluminum substrate, at a high density. Emitted light is made to be incident on a photographic film via an acrylic block. Since light emitted from the LED chips 64 has a high color temperature and includes a large amount of light of short wavelengths, an SN ratio of a read image is excellent and the image can be read at high speed. A heat pipe is piped at the rear surface side of the aluminum substrate and a coolant is circulated inside the pipe. Since heat generated by the LED chips is transmitted to the heat pipe through a heat exchange action between the light source and the coolant, the amount of light emitted from the LED chips 64 does not fluctuate. |