This invention addresses the scalability problem of periodic "nanostructured" surface treatments such as those formed by interference lithography. A novel but simple method is described that achieves seamless stitching of nanostructure surface textures at the pattern exposure level. The described tiling approach will enable scaling up of coherent nanostructured surfaces to arbitrary area sizes. Such a large form factor nanotechnology will be essential for fabricating large aperture, coherent diffractive elements. Other applications include high performance, antiglare/antireflection and smudge resistant Motheye treatments for display products such as PDA's, laptop computers, large screen TV's, cockpit canopies, instrument panels, missile and targeting domes, and, more recently, "negative-index" surfaces. Although ideal for seamless stitching of nanometer scale patterns, the technology is broadly applicable to any situation where an arbitrarily large area needs to be seamlessly tiled with a smaller base pattern that has periodic overlap able boundaries.