초록 |
A mechanical sensor that is capable of distinguishing types of deformation with their strain has been massively paid attention in material engineering and various industries. So far, highly accurate and quantitative mechanical sensors have been developed based on electrical signaling system and widely used in industries for diagnosis of device lifetime and safety issues. However, it is still extremely challenge to differentiate types of deformation using mechanical sensors with electric signaling system because of signal interference and complex fabrication process. Here, we fabricate photonic crystal elastomer film that is consisting of cholesteric liquid crystals(CLCs) showing helical layering structure normal to the film. Because of unusually high Poisson ratio of the CLC elastomer ( >0.5), the CLC film shows a susceptive responsibility to external stress with various curvatures by locally varying the photonic band gap over the film from IR(infrared radiation) to the UV(ultra violet) region within 30% strain. Based on the CLC film, we demonstrated the mechanical stimuli-responsive photonic sensor that is capable of presenting not only quantitative but also qualitative deformation including not only simple stretching but also bending with direction out of plane, in plane, and even complex deformation with Gaussian curvature. Our result can provide new type of platform for mechanochromic sensors. |