Image recording apparatus

摘要

An image recording apparatus includes a recording drum rotatable with a printing plate mounted peripherally thereof, a recording head for recording an image on the printing plate, a rotary encoder for detecting a rotation angle of the recording drum, sensors for detecting the printing plate mounted on the recording drum, a detection range setting circuit for setting a range of detection of the sensors with respect to the rotation angle of the recording drum according to information on the material of the printing plate, information on reflectance of the printing plate and the presence or absence and the type of positioning holes formed in the printing plate, and a determining circuit for determining a position of an edge of the printing plate mounted on the recording drum, by fetching signals from the sensors based on the rotation angle of the recording drum and the range of detection set by the detection range setting circuit.