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A maskless single beam process for photofabrication of surface microstructures is reported. A continuously moving azopolymer film is illuminated with structured polarized light from a 488 nm laser and spatial light modulator, driving the formation of surface relief gratings in real time. The structures were replicated using nanoimprint lithography, and exhibited a maximum diffraction efficiency of order 30% at 633 nm. Using the period tunability of the spatial light modulator, surface gratings were fabricated that diffract red, green, and blue light along a common direction, illustrating the potential of this fabrication platform in the field of structured color. 

A versatile system for the fabrication of surface microstructures is demonstrated by combining the photomechanical response of supramolecular azopolymers with structured polarized illumination from a high resolution spatial light modulator. Surface relief structures with periods 900 nm - 16.5 µm and amplitudes up to 1.0 µm can be fabricated with a single 5 sec exposure at 488 nm. Sinusoidal, circular, and chirped surface profiles can be fabricated via direct programming of the spatial light modulator, with no optomechanical realignment required. Surface microstructures can be combined into macroscopic areas by mechanical translation followed by exposure. The surface structures grow immediately in response to illumination, can be visually observed in real time, and require no post-exposure processing. 

Abstract Thin film supramolecular azopolymers support the all‐optical generation of dynamic surface microstructures. Using a spatial light modulator (SLM) illuminated at 488 nm, structured polarized light drives surface waves of sinusoidal profile with periods 700 nm–5 µm at speeds up to 1 µm s⁻¹. Multiple regions on the film surface within the SLM focal plane can be independently set into motion, each with unique period, speed, amplitude, and propagation direction. The underlying mechanism is the photomechanical response of the azopolymer, which is more commonly exploited for the fabrication of static surface microstructures. Hydrogen‐bonded systems such as the supramolecular system described here are particularly advantageous due to their facile fabrication from commercially available components. In addition to applications in dynamic diffractive optics, this programmable system for optical surface waves is well‐suited for studies in nanoparticle manipulation, as well as in bioengineering as a reconfigurable surface template for directed cell growth.