Image reading device

Abstract

Abstract PURPOSE:To realize proper compensation of continuation which improves reliability by realizing compensation of continuation in the main scanning direction of the image which is read by two image pick up means based on two indexes provided at the part which does not correspond to the effective image reading area in the standard white plate for shading compensation. CONSTITUTION:First, a standard white plate 49 is read before starting original scanning, and high-order n bits (e.g. 128 bits) of the first CCD47-system signal and low-order n bits (e.g. 128 bits) of the second CCD48-system signal are compared. In respective 128 bit data, the condition can be confirmed that black bit data B is intervened by white bit data W as shown in the diagram. Here, the distance of a fine black lines 55 and 56, that is, the number of effective reading bits of the main scanning direction is determined beforehand. Therefore, the number of overlapped reading bits of the first CCD and the second CCD can be calculated from the number of the high-order white bits (W10) of the first CCD- system signal and the number of the low-order white bits (W13) of the second CCD-system signal, and these can execute the compensation of continuation of the reading image.

Inventors

• 👤 Yoshinori Ejima
• 👤 義紀 江島

Bibliographic Details