title: Micro-strain sensing using wrinkled stiff thin films on soft substrates as tunable optical grating.
abstract: We report a strain sensing approach that utilizes wrinkled patterns on poly (dimethylsiloxane) (PDMS) as an optical grating to measure thermally-induced strain of different materials. The mechanism for the strain sensing and the effect of PDMS grating on strain sensing are discussed. By bonding the PDMS grating onto a copper or silicon substrate, the coefficient of thermal expansion (CTE) of the substrates can be deduced by measuring the diffraction angle change due to the change in PDMS grating periodicity when thermal strain is introduced. The measured CTEs agree well with the known reference values.
authors.affiliation: School for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, AZ, USA.
authors.forename: Teng
authors.initials: T
authors.lastname: Ma
authors.forename: Hanshuang
authors.initials: H
authors.lastname: Liang
authors.forename: George
authors.initials: G
authors.lastname: Chen
authors.forename: Benny
authors.initials: B
authors.lastname: Poon
authors.forename: Hanqing
authors.initials: H
authors.lastname: Jiang
authors.forename: Hongbin
authors.initials: H
authors.lastname: Yu
mesh_terms: D004129:Dimethylpolysiloxanes / Q000737:chemistry*; D055119:Elastic Modulus; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006244:Hardness; D008567:Membranes, Artificial; D012031:Refractometry / Q000295:instrumentation*; D013314:Stress, Mechanical; D014159:Transducers
chemical_list: D004129:Dimethylpolysiloxanes; D008567:Membranes, Artificial; C013830:baysilon