Method for screening color separations of a lenticular image, computer program product and method for producing a lenticular image on a printing material

A Non-Transitory internal memory of a digital computer loaded with a computer program and stored on a computer-suitable medium and including software code sections executable by a computer processor to perform all of the method steps of screening color separations of a lenticular image having a lenticular frequency of lenticular lenses required for viewing the lenticular image and having a lens width l,

• the method comprising the following steps:
• calculating an amplitude-modulated halftone image for each color separation at least at one screen angle having a tangent being a rational number and with at least one screen frequency;
• providing a screen with non-orthogonal screen cells spanned by vectors u and v
• for at least one specific color separation of the color separations;
• defining a distance k;
• defining directions of the vectors u and v relating to a perpendicular direction with respect to image strips of the lenticular image for the specific color separation;
• defining a first pair of rational numbers (n, m);
• defining a second pair of rational numbers (i, j);
• and
• satisfying a system of equations:
• n*Ux +m*Vx =O, n*Uy +m*Vy =1, i*ux-j*Vx =k and i*uy-j*Vy =0
• for vectors u =(Ux, Uy) and v =(Vx, Vy) spanning the screen cells.

A method for producing a lenticular image on a printing material, the method comprising the following steps:

• exposing each of the color separations calculated according to the method steps of screening color separations of a lenticular image having a lenticular frequency of lenticular lenses required for viewing the lenticular image and having a lens width I,
• the method comprising the following steps:
• calculating an amplitude-modulated halftone image for each color separation at least at one screen angle having a tangent being a rational number and with at least one screen frequency;
• providing a screen with non-orthogonal screen cells spanned by vectors u and v for at least one specific color separation of the color separations;
• defining a distance k;
• defining directions of the vectors u and v relating to a perpendicular direction with respect to image strips of the lenticular image for the specific color separation;
• defining a first pair of rational numbers (n, m);
• defining a second pair of rational numbers (i, j);
• and
• satisfying a system of equations:
• n*Ux +m*Vx =0, n*Uy +m*Vy =1, i*ux-j*Vx =k and i*uy-j*Vy =0
• for vectors u =(Ux, Uy) and v =(Vx, Vy) spanning the screen cells.
• wherein the image strips of the lenticular image is printed onto a printing form;
• and printing the exposed printing forms onto a printing material in combination printing in a printing machine, to create a multicolored lenticular image on the printing material.