SPIE Proceedings [SPIE Eighth International Symposium on Advanced Optical Manufacturing and Testing Technology (AOMATT2016) - Suzhou, China (Tuesday 26 April 2016)] 8th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Design, Manufacturing, and Testing of Micro- and Nano-Optical Devices and Systems; and Smart Structures and Materials - High-sensitivity refractive index sensor based on microfiber long period gratings with CO 2 laser line-by-line inscription