These original Kirt's Cogitations™ may be reproduced
(no more than 5, please) provided proper credit is given to me, Kirt Blattenberger.
here to return to the Table of Contents.
Cog·i·ta·tion [koj-i-tey'-shun] – noun: Concerted
reflection; meditation; contemplation.
Kirt [kert] – proper noun: RF Cafe webmaster.
Piezoelectric foam? Researchers have discovered that
polypropylene foam (used widely in packaging) acquires piezoelectric properties after it is zapped with several
thousand volts. Air in the pores break down into electrons and positively charged ions that cling to opposite
walls of the cavities. It is already being used in keypads and musical instrument pickups. Future applications
include conformable ultrasound arrays for medical instrumentation and even embedded ultrasonic "bar code" type
configurations built into products for security and identification. The only drawback that needs to be overcome is
the material loses its piezoelectric properties above 55° C.