A fast, accurate and reliable sensor applicable to chemical and biological analytes resides in an optical grating-based sensor, sensing system, and method of use. The sensor, configured for use with an illumination source and a signal detector in the system embodiment, includes first and second periodic...http://www.google.com.au/patents/US20040145752?utm_source=gb-gplus-sharePatent US20040145752 - Grating sensor
