An optical pickup has a laser mounting surface formed around an opening portion of a laser hole while a notch groove ranging from the laser mounting surface to an operating hole is formed in a laser hole side wall portion. In the process, a moving fibrous web is conditioned after the drier unit of a papermaking machine by applying a flow of moistened gas through one or more arrays of radial jet reattachment nozzles placed in close proximity to the web surface prior to a calendering unit or prior to a steaming unit placed between the nozzles and the calender unit to cool the web andor increase its moisture content. The data processing part of the service object applies a colorization process according to the content of colorization information, and generates a print command for two-color printing. The mass symmetry respective to the rotation axis is improved.