| 摘要 |
PURPOSE:To receive the reflected light from an illuminated character or the like on an image sensor with a uniform illuminance by increasing the illuminance of a light source according as going from the center toward ends of the visual field illuminated with the light source. CONSTITUTION:Plural LEDs 9 having the same luminance are arranged on a substrate 8 as a surface light source 2 arranged in a hand-scanner 1. The number of LEDs 9 arranged at ends of the illuminated visual field is larger so that LEDs are arranged more closely toward ends of the illuminated visual feld. Since characters or the like placed at ends of the illuminated visual field are more illuminated than the center of the visual field, the reflected light from these characters or the like is stronger than that from characters or the like in the center. However, the reflected light from ends of the visual field is more attenuated than that from the center and both of them are received on an image sensor with the same illuminance. As the result, read character or the like are accurately discriminated because the reflected light from characters or the like is received on the image sensor with a uniform illuminance.
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