Tunable window device based on micro-wrinkling of nanometric zinc-oxide thin film on elastomer

• Main Authors: Shrestha, Milan, Lau, Gih-Keong
• Other Authors: School of Mechanical and Aerospace Engineering
• Format: Article
• Language: English
• Published: 2016
• Subjects: elastomer; tunable window device
• Online Access: https://hdl.handle.net/10356/84024; http://hdl.handle.net/10220/41546
• Institution: Nanyang Technological University

This Letter presents a tunable window device based on microscopic wrinkling of a transparent elastomeric surface. “Crack-free” microscopic wrinkling of a 50-nm ZnO thin film is possible on a highly adhesive acrylic elastomer membrane (VHB 4910) upon partial release from a large radial pre-stretch of membrane. This ZnO-based tunable window device demonstrates reversible tunability between transparent and translucent states. At zero compression with a flat surface, the device is transparent with a 93% in-line transmittance at 550-nm wavelength. At 14% radial compression with wrinkled surface, the device appears translucent with a 3% in-line transmittance. Analysis shows that a large amplitude and a small wavelength of transparent micro-wrinkles are good for refracting light diffusely. This method and material system are promising to make a low-cost, high-performance smart window.