Title :
Displacement sensor based on pyroelectric thick films and contactless light-spot cursor
Author :
Ferrari, Vittorio ; Marioli, Daniele ; Taroni, Andrea
Author_Institution :
Dipt. di Elettronica, Brescia Univ., Italy
Abstract :
A sensor is presented to measure translational displacement exploiting the position-dependent signals generated by pyroelectric films when excited by a movable LED that works as a contactless light-spot cursor. The pyroelectric films are made of PZT screen-printed on alumina substrate by the thick-film technology. The sensor employs a differential configuration which minimizes the sensitivity towards mechanical vibrations and microphonics caused by the piezoelectric response of PZT. An electronic circuit based on excitation modulation and synchronous rectification rejects the interference from thermal and light background. The sensor principle, design, and manufacturing are described and experimental results from the device characterization are reported
Keywords :
demodulation; dielectric polarisation; displacement measurement; electric sensing devices; lead compounds; pyroelectric detectors; rectification; thick film devices; thick films; PZT; PbZrO3TiO3; alumina substrate; contactless light-spot cursor; differential configuration; displacement sensor; excitation modulation; interference rejection; movable LED excited; poling; position-dependent signals; pyroelectric thick films; screen-printed PZT; synchronous demodulation; synchronous rectification; translational displacement measurement; Displacement measurement; Light emitting diodes; Mechanical sensors; Piezoelectric films; Position measurement; Pyroelectricity; Signal generators; Thick film sensors; Thick films; Vibrations;
Conference_Titel :
Instrumentation and Measurement Technology Conference, 2001. IMTC 2001. Proceedings of the 18th IEEE
Conference_Location :
Budapest
Print_ISBN :
0-7803-6646-8
DOI :
10.1109/IMTC.2001.928826
