| 主权项 |
1. Apparatus for printing a laser markable medium, comprising:
a sheet of the medium in a printing plane, the sheet having a width; a collimating module held in a fixed position, the collimating module including a collimating lens; a focusing module including a turning mirror and a focusing lens, the focusing module being reciprocally translatable along an axis about parallel to the printing plane; a source of laser-radiation and an optical fiber for transporting the laser-radiation from the source thereof to the collimating module and delivering the laser-radiation from a distal end thereof in a diverging beam to the collimating lens; the collimating lens arranged to collimate the diverging beam from the optical fiber and direct the collimated beam to the focusing module, the turning minor directing the collimated beam to the focusing lens and the focusing lens focusing the collimated beam onto the sheet at a focal distance from the focusing lens for printing on the sheet; and a detector arranged to provide a signal representative of power of the focused beam on the sheet, the signal being delivered to an electronic module cooperative with the laser-radiation source for maintaining power of the focused beam on the sheet about constant wherein the detector is housed in a diagnostic module adjacent the sheet in a translation path of the focused beam, the diagnostic module covered by a diagnostic plate including a plurality of slots extending therethrough and aligned along the translation path, each of the slots for allowing at least part of the focused beam to enter the diagnostic module for optical access to the detector. |
