| 摘要 |
PURPOSE:To surely detect the position of a head and to achieve the compensation of density with high accuracy, by detecting the position of the head and controlling exposure through the use of optical codes of optical patterns consisting of the combination of a lot of parallel lines. CONSTITUTION:A head section 1 is provided for a support 11 freely slidably, and the support 11 is fitted with a transparent acrylic code plate 12, a gray code as an optical code 12A is printed for 1 as an opaque section and for 0 as a transparent section. When the same digit of adjacent code is 1, this is linked to be taken as an optical pattern consisting of the combination of a lot of parallel lines. With this constitution, the said code is read with a detector 14 of the head section 1 and after the code is changed into the decimal system at a decoder 15, a shutter 6 is controlled via an operation circuit 16 and a shutter control circuit 17. Thus, the position of the head section can accurately be detected for density compensation with high accuracy. |
