so i have been researching PVDF piezo film sensors via a technical manual [0] and there is a lot here that may be of potential interest in terms of its applications, [1] especially its use in security systems and to prevent tampering, and energy harvesting, in addition to other areas where its unique functionality could be explored. what follows, a series of short posts about this material... 0a. Measurement Specialties PVDF technical manual (PDF) http://contactmicrophones.com/techman.pdf 0b. technical manual with Appendix of piezo film articles http://www.tufts.edu/programs/mma/emid/piezo.pdf 1. Measurement Specialties Piezo Film Product Guide http://www.meas-spec.com/downloads/Piezo_Film_Product_Guide.pdf --- so PVDF is 'piezo film' that has unique properties and capabilities. while i know little of functional electronics, it is said to be a capacitor that stores and discharges high voltage energy. like a piezo disk it picks up the vibrational energy due to structural deformation that then generates or moves charge in response to this. the application i recently first encountered it was with 'contact microphones' - where it was stated that these PVDF film tab mics record the vibrations as sound input rather than acoustic pressure of condenser and dynamic capsule microphones reliant on soundwaves moving the air. so the distinction is that this piezo film can function as a recording input or SENSOR though by registering the vibrations on the surface of a material. what is more, it also detects temperature differences and thus can be employed as a sensor this way as well, which i did not realize was possible nor expect for a 'microphone'. the PVDF film apparently is already used in security applications within computers, if not crypto systems protected from tampering, via vibration sensing that triggers lock down or equipment destruction based upon monitoring of piezo film signals at perimeter. PVDF film for Tamper-Proofing, Security (white paper) http://www.meas-spec.com/downloads/Applying_Piezoelectric_Film_in_Electronic... (interesting likewise is use of piezo coaxial cable for perimeter security, strung on fencing as a microphone and also buried underground, which then can register & record raindrops, footsteps, people climbing fence, etc.) to be continued: ideas and observations about PVDF... spatter glass, azimuth circle, rift zone