Patent ID: 8593702

Claim:
An image reader comprising: a first image reading unit comprising a first sensor configured to read an image on a first side of a first document sheet being conveyed on a feeding path, and output a first analog signal corresponding to the read image of the first side; a second image reading unit comprising: a second sensor configured to read an image on a second side opposite to the first side of the first document sheet being conveyed on the feeding path, and output a second analog signal corresponding to the read image of the second side; an analog-digital converter configured to convert the second analog signal output from the second sensor into a first-order digital signal, and output the first-order digital signal; and a differential transmitter configured to convert the first-order digital signal output from the analog-digital converter into a second-order digital signal for differential transmission so as to reduce crosstalk interference with the first analog signal output from the first sensor of the first image reading unit, and output the second-order digital signal in a differential transmission method; and a processor configured to process the first analog signal output from the first sensor of the first reading unit and the second-order digital signal output from the differential transmitter of the second image reading unit.