IMAGE SENSOR

PROBLEM TO BE SOLVED: To provide an image sensor for reducing degradation of precision of reading an original when brightness of a light source is caused by a change in an environmental temperature, deterioration with age, or the like of a transmission light source. SOLUTION: The image sensor includes: a light transmitting body 4 including a carrying area of an original 1 and extending in a direction orthogonal to a carrying direction of the original 1; a reference criterion part 8 which is provided outside the carrying area in the orthogonal direction and presents transmissivity lower than that of the light in the carrying area; a light source means 3 for irradiating the carrying area and the reference criterion part 8 with light; a light receiving part 13 which is located opposite to the light source means 3, receives the transmission light passing through a lens array 12 converging transmission lights transmitted through the original 1 to be carried in the carrying area and the reference criterion part 8, and outputs an electric signal; an amplifier for amplifying the electric signal of the original 1 corresponding to the carrying area of the light receiving part 13 to output an image signal of the original 1; and a control means for controlling amplification rate of the amplifier on the basis of the electric signal corresponding to the reference criterion part 8. COPYRIGHT: (C)2008,JPO&INPIT