公开(公告)号：US20210402821A1

公开(公告)日：2021-12-30

申请号：US16917044

申请日：2020-06-30

Applicant: Xerox Corporation

Inventor： David C. CRAIG ,  Mark J. HIRSCH ,  Mark C. PETROPOULOS ,  Eliud ROBLES FLORES

IPC: B41N3/08 ,  B41F33/00 ,  B41F7/24

Abstract: According to aspects of the embodiments, there is provided a method of determining the amount of fountain solution employed in a digital offset lithography printing system. Fountain solution thickness is determined by examining optical density of some halftone or solid patch versus laser current level. The apparatus and method uses a variable current signal to dither or perturb the laser imaging system to irradiate a fountain solution layer to create patches at different laser current levels. An aptly programmed controller then process optical density measurements to indirectly estimate fountain solution level.

公开(公告)号：US20210402756A1

公开(公告)日：2021-12-30

申请号：US16916907

申请日：2020-06-30

Applicant: Xerox Corporation

Inventor： Mark J. HIRSCH ,  David C. CRAIG ,  Mark C. PETROPOULOS ,  Eliud ROBLES FLORES

IPC: B41F33/00 ,  B41M1/06 ,  B41F7/02

Abstract: According to aspects of the embodiments, there is provided a method of determining the amount of fountain solution employed in a digital offset lithography printing system. Fountain solution thickness is determined from diagnostic images that are printed and analyzed using the existing Image Based Controls (IBC). An analysis of the density of solids, halftones, and background as a function of the fountain solution control parameter is performed to decide on the appropriate level of fountain solution. A latitude window of control parameters is then derived for which the digital offset lithography printing system in operation minimizes the undesirable effects of too much or too little fountain solution.