Linear illuminator for reading separated color image using linear sensor

摘要

A linear illuminator for image reading by the use of a linear sensor comprises a linear illumination light source, a cylindrical rotational member provided about the circumference of the linear illumination light source, and plurality of color separation filters installed on the rotational member. By controlling the rotation of the rotational member, plural kinds of color separation linear illumination light are output in the time series. The cylinder may have a shielding area between filters, which enables measurement of the dark current of the linear sensor.