Optical printer with color filter and optical printing method

Abstract

An optical printer records a color image by exposing color instant photo film extending two-dimensionally in a main scan direction and a sub scan direction. The optical printer includes a printing head, which includes a white color light-emitting element and a color separation filter unit. The color separation filter unit is disposed in a light path of white-color light from the light-emitting element, for color separation of the white-color light. The color separation filter unit has a tubular shape, has a central axis extending substantially parallel with the main scan direction, and is rotatable about the central axis. The white-color light travels through an entrance position along the light path into the color separation filter unit, out of which the light travels through an exit position along the light path. The color separation filter unit includes three color filters, arranged about the central axis, having selectivity of a wavelength, for converting the white-color light into printing light of respectively single colors. The three color filters are so disposed that a single one thereof is in the entrance position or the exit position in a manner irrespective of a rotation position with reference to the central axis. Three transparent plates are arranged alternately with the three color filters.