| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an inner drum exposure device capable of preventing uneven exposure on a recording material due to flare light which generates on the reflecting surface of a reflecting mirror for aligning the optical axis of a light beam to a center axis and is directly incident to the photosensitive surface of the recording material, and capable of carrying out scanning exposure, without generating degradation in picture quality due to the flare light. <P>SOLUTION: The inner drum exposure device holds a recording medium in a recording region on the inner circumference face of a cylinder of a support and deflects a light beam, incident to the inside of the support along the center axis by a deflecting means to scan and expose the recording medium, is such that the device is equipped with a light-shielding plate disposed on the downstream side of a reflecting mirror which aligns the optical axis of the light beam to the center axis so as to eliminate flare light that exposes the recording material. If the radius of the light beam incident on the reflecting mirror, the distance from the center axis to the inner surface, the distance from the reflecting mirror on the center axis to an end of the recording region in the farthest side, the distance from the reflecting mirror to the light-shielding plate, and the distance from the optical axis to an edge of the aperture farthest from the optical axis are set as r, R, L, d and X, respectively, expression r<X≤(R+r)d/(L+r)-r is satisfied. <P>COPYRIGHT: (C)2008,JPO&INPIT |
