Patent ID: 7522323

Claim:
A method for printing a pattern from a total internal reflection hologram of a hologram mask into a photosensitive layer on a substrate, which method includes: a) arranging the hologram mask on a first face of a coupling element; b) arranging the substrate so that it is substantially parallel with the hologram mask and such that the photosensitive layer is separated from the hologram by an amount substantially corresponding to the focal distance of the hologram mask; c) reconstructing the pattern recorded in the hologram by scanning an exposure beam of substantially collimated light across the hologram mask through a second face of the coupling element while simultaneously measuring the local separation between the hologram and photosensitive layer in at least two locations where the pattern is being instantaneously reconstructed by the exposure beam by scanning at least two focus beams across the hologram mask through the second or a third face of said coupling element and, in response to said measurements by the focus beams, continuously adjusting both the separation of the hologram mask and substrate and the angle of tilt between them in at least the plane orthogonal to the direction of motion of the scanning beams, in order that the pattern reconstructed from the hologram is accurately printed in focus into the photosensitive layer.