Patent ID: 8243351
Filing Date: 2012-08-14
Classification: H04N

Abstract:
1. An image reading apparatus which irradiates an image original with light, receives reflected light, and reads the image original based on the received light, the apparatus comprising: light emitting means for emitting light components of three primary colors; light receiving means for receiving the light reflected by the image original irradiated with the light emitting means; image processing means for processing image data obtained based on the reflected light received by the light receiving means; and lighting control means for controlling the light emitting means to read the image original using one of primary color reading performed by causing the light emitting means to sequentially irradiate the image original with the light components of three primary colors and read the image original, and complementary color reading performed by causing the light emitting means to irradiate the image original with one of three different color combinations, which includes two of the light components of three primary colors, and read the image original, wherein the image processing means executes shading correction of the image data based on calibration data obtained by calibrating the light emitting means, wherein an ON period of the light emitting means at a time upon the primary color reading is longer than that upon the complementary color reading, and wherein a criterion as to whether or not the calibration is performed again upon the primary color reading differs from that upon the complementary color reading.