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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.
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Optical microstructure fabrication using structured polarized illumination
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.
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- PAR ID:
- 10369123
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Optics Express
- Volume:
- 30
- Issue:
- 5
- ISSN:
- 1094-4087; OPEXFF
- Format(s):
- Medium: X Size: Article No. 7308
- Size(s):
- Article No. 7308
- Sponsoring Org:
- National Science Foundation
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