| 摘要 |
PURPOSE:To correct the irregularity of an original readout signal due to the influence of a light source and a lens by detecting the irregularity of the original readout signal and then generating a correcting signal which corresponds to the result of the detection. CONSTITUTION:A readout singal inputted from an input terminal 18 is applied to a maximum value detecting circuit 20 through an A/D converter 19. Assuming that the maximum value detecting circuit 20 outputs a value of irregularity regarding a picture element A, this signal is inputted to a one-line delay circuit 22 and a one-picture-element delay circuit 21 to achieve delay by one line and one picture element. The outputs of those delay circuits are multiplied by prescribed constants before being inputted to a maximum value counting circuit 20. Consequently, the maximum value among the value of a picture element C read at present, the value of the irregularity of the readout signal of a picture element B just before it, and the value of the irregularity of the readout singal of a picture element A one line before is regarded as the value of the irregularity of the picture element C, and this is utilized as a correction signal. |
