Hauv thaj chaw ntawm kev sim ua kom tsis muaj kev puas tsuaj, ultrasonic thev naus laus zis tau nyiam ntau xim vim tias nws cov kev ntsuas siab thiab ua tau zoo. Raws li qhov tseem ceeb tseem ceeb ntawm kev kuaj ultrasonic, qhov kev xaiv ntawm tofd (lub sij hawm ntawm lub davhlau diffractact) kev soj ntsuam ncaj qha rau qhov tseeb thiab kev ntseeg tau ntawm kev sim cov txiaj ntsig. Daim ntawv no yuav txheeb xyuas cov khoom ua rau cov yam ntxwv ntawm kev sojntsuam tam sim no thiab qhia nws cov tub ntxhais kawm txoj haujlwm hauv ultrasonic kuaj.
Cov khoom siv tseem ceeb ntawm cov tshuaj tiv thaiv ntawm ToFD yog piezoelectric siv lead ua, uas yog cov ntaub ntawv tshwj xeeb nrog cov nyhuv piezoelectric. Thaum cov piezoelectric muaj ua tiav los ntawm sab nraud rog, lawv tuaj yeem tsim cov nqi hluav taws xob thiab paub txog kev sib nrig sib kho ntawm cov tshuab hluav taws xob thiab hluav taws xob. Hauv ultrasonic kuaj, Piezoelecric muaj peev xwm hloov kho cov cim hluav taws xob rau hauv cov phiaj xwm ultrasonic thiab kis lawv mus rau cov ntaub ntawv sim los ntawm kev sim ua ntej.
Cov khoom siv ua ke piezoelectric crystal cov ntaub ntawv muaj xws li quartz, txhuas zaconate titanate (pzt) thiab lwm yam. Cov ntaub ntawv no muaj cov siab siab, dav zaus band thiab zoo ruaj khov, uas tuaj yeem xyuas kom muaj tseeb kis thiab txais tos ntawm ultrasonic cim. Tsis tas li ntawd, cov corrosion tsis kam ntawm piezoelecric muaju tseem yog qhov tseem ceeb tshaj plaws los txiav txim siab thaum xaiv cov khoom, vim tias qhov chaw kuaj xyuas tuaj yeem suav nrog ntau yam ntawm cov corrosive media.
Ntxiv rau cov piezoelectric muaju, tofd probes kuj muaj lwm cov ntaub ntawv tso tawm, xws li cov xwm txheej hlau, rwb thaiv tsev thiab cov xov hlau. Kev xaiv ntawm cov ntaub ntawv no tseem cuam tshuam rau kev ua tau zoo thiab kev pabcuam lub neej ntawm kev sojntsuam. Lub plhaub hlau yuav tsum muaj cov tshuab ua kom zoo zog thiab kev tiv thaiv los tiv thaiv cov ncuav qab zib sab hauv los ntawm kev puas tsuaj sab nraud. Rwb thaiv tsev yog siv los tiv thaiv kev lom zem ntawm cov cim hluav taws xob thiab ua kom muaj kev sib kis hluav taws xob. Qhov txuas txuas hlau yog lub luag haujlwm rau kev sib txuas rau cov kev sojntsuam nrog cov khoom ntsuas kom paub cov ntaub ntawv sib kis thiab kev ua tiav.
Txhawm rau kom suav, cov khoom siv ntawm cov sojntsuam Los ntawm xaiv tsim nyog piezoelecric muaju thiab cov ntaub ntawv ruaj khov, cov ruaj khov ntawm kev sojntsuam hauv cov txheej txheem kuaj tau tuaj yeem ua kom tiav. Nrog rau kev tshwm sim txuas ntxiv ntawm cov ntaub ntawv tshiab thiab kev nce qib txuas ntxiv ntawm cov thev naus laus zis, uas yuav ua rau kev hloov pauv ntau dua thiab tawg mus rau qhov kev sim ua haujlwm tsis yog kev sim siab.