公开(公告)号：US20190351689A1

公开(公告)日：2019-11-21

申请号：US15985065

申请日：2018-05-21

Applicant: Xerox Corporation

Inventor： EDWARD N. CHAPMAN

IPC: B41M3/14 ,  H04N1/00 ,  G03G21/04 ,  G07D7/00 ,  G06K1/12

Abstract: An original document is formed using a first print medium by printing a first and second monochrome patterns with a single colorant to form printed first and second regions including first and second shapes, respectively, which are devoid of the colorant. The second shapes have a smaller size and a higher frequency than the first shapes. The first and/or second regions encode information. The first and second patterns and a fluorescence of the first print medium are selected such that the first and second regions of the original document are indistinguishable to the naked eye, under both normal and ultraviolet illumination but are distinguishable, only under the ultraviolet illumination, in a copy formed by scanning the original document and printing the scanned document on a second print medium with a plurality of colorants, to reveal the encoded information.

公开(公告)号：US20150269703A1

公开(公告)日：2015-09-24

申请号：US14220866

申请日：2014-03-20

Applicant: XEROX CORPORATION

Inventor： EDWARD N. CHAPMAN

IPC: G06T1/00 ,  H04N1/32

CPC classification number: G06T1/0021 ,  B41M3/008 ,  B41M3/10 ,  B41M3/14 ,  B42D25/333 ,  G06T2201/0051 ,  G06T2201/0062 ,  H04N1/32144 ,  H04N1/32208 ,  H04N1/32251 ,  H04N1/32561 ,  H04N2201/3239 ,  H04N2201/3243

Abstract: Methods and systems rasterize a document to produce a bitmap having first pixels of a first color as background uniformly located across a watermark region and second pixels of a second color located in a pattern forming foreground items within the watermark region. The rasterization causes the first pixels to deposit a first marking material (forming the first color) to a first height on the print media, and the rasterization causes the second pixels to deposit a second marking material (forming the second color) to a second height (different from the first height) on the print media. In the printed document, by having the first color be different from the second color and the second height be different from the first height, this causes the relative darkness between the background and the foreground items to reverse when the printed document is viewed from different angles (relative to a light source).

Abstract translation: 方法和系统光栅化文档以产生具有第一颜色的第一像素的位图，作为横跨水印区域均匀定位的背景，以及位于形成水印区域内的前景项目的图案中的第二颜色的第二像素。 光栅化使得第一像素将第一标记材料（形成第一颜色）沉积到打印介质上的第一高度，并且光栅化使得第二像素将第二标记材料（形成第二颜色）沉积到第二高度 （与第一个高度不同）在打印介质上。 在打印文档中，通过使第一颜色与第二颜色不同，第二高度不同于第一高度，这导致当从不同角度观看打印文档时背景与前景项之间的相对暗度反转 （相对于光源）。