Patent ID: 8418612
Filing Date: 2013-04-16
Classification: B23K,B41C

Abstract:
1. A printing plate making apparatus configured to scan a recording medium by a light beam at a predetermined pixel pitch, thereby engraving a surface of the recording medium to make a printing plate, wherein: the light beam includes a first light beam and a second light beam, a light power of the first light beam is P the printing plate making apparatus is configured such that, after scanning the recording medium with one of the first and second light beams at a predetermined pixel pitch to engrave the recording medium to a first depth d an upstream end of a convex portion forming an upper portion of a region where the recording medium is to be left in a convex shape is defined as an upstream reference position; the printing plate making apparatus is configured to control light power of the first light beam such that, when the recording medium is scanned at a predetermined pixel pitch with the first light beam, from a first point which is separated from the upstream reference position by m pixels in the scanning direction, or the vicinity thereof, to a second point on the surface of the recording medium separated from the upstream reference position by n pixels downstream in the scanning direction, a light power of the first light beam is reduced linearly or substantially linearly from P when the recording medium is scanned by the second light beam at a predetermined pixel pitch, from a third point or the vicinity thereof, the third point being separated from the upstream reference position by (2m+n)×(P