Patent ID: 7589868

Claim:
A method for creating a print file for making a printing master used for contact printing, by printing a 3-D print using a 3-D printing system, the 3-D print including a plurality of 3-D structures printed on a substrate, each 3-D print structure having a height with respect to the substrate, the method comprising the steps of: providing a two-dimensional source image including a plurality of image pixels; generating a filtered image by applying a topographic operator to the source image to generate for every image pixel a representation of a pixel height profile value, each pixel height profile value of the filtered image corresponding to a cross-section layer through the 3-D print structure which is to be formed by 3-D printing, thereby including in the filtered image definitions of a plurality of image layers to be printed using the 3-D printing system, the topographic operator having the properties to ensure that: any cross-section through a solid section of the formed 3-D print structure at a second level in the 3-D print structure which is closer to the substrate than a first level has an area which is equal to or larger than the area of the cross-section of the 3-D print structure at the first level; and the heights of all 3-D print structures in the pixel height profile values which define the printing contact surface all lie substantially within a single printing surface above the substrate before the 3-D printing of the 3-D print structures; slicing the picture height profile values of the filtered image into a plurality of image layers; and outputting the print file based on the plurality of image layers; wherein the step of applying the topographic operator includes: generating binary halftone dots from the source image; thereafter transforming the binary halftone dots into blurred halftone dots having a height profile in the form of a plurality of blurred halftone dot layers; and thereafter choosing a blurred halftone dot layer to be printed as an image layer.