{"id":61231,"date":"2023-04-21T14:25:00","date_gmt":"2023-04-21T19:25:00","guid":{"rendered":"https:\/\/www.bjultrasonic.com\/how-does-a-piezoelectric-sensor-work\/"},"modified":"2025-01-27T06:05:46","modified_gmt":"2025-01-27T11:05:46","slug":"how-does-a-piezoelectric-sensor-work","status":"publish","type":"post","link":"https:\/\/www.bjultrasonic.com\/cs\/how-does-a-piezoelectric-sensor-work\/","title":{"rendered":"Piezoelektrick\u00e9 senzory: princip a funkce"},"content":{"rendered":"<p>Piezoelektrick\u00e9 senzory jsou fascinuj\u00edc\u00ed za\u0159\u00edzen\u00ed, kter\u00e1 dok\u00e1\u017e\u00ed p\u0159ev\u00e1d\u011bt mechanickou energii na energii elektrickou a naopak.  Tento princip, objeven\u00fd v roce 1880 Pierrem a Jacquesem Curie, nach\u00e1z\u00ed \u0161irok\u00e9 uplatn\u011bn\u00ed v mnoha oblastech modern\u00ed technologie.  Tento \u010dl\u00e1nek se podrobn\u011bji zam\u011b\u0159\u00ed na princip fungov\u00e1n\u00ed t\u011bchto senzor\u016f a jejich specifick\u00e9 vlastnosti.<\/p>\n<p>Piezoelektrick\u00fd efekt: Z\u00e1kladn\u00ed princip<\/p>\n<p>Piezoelektrick\u00fd efekt je fyzik\u00e1ln\u00ed jev, kter\u00fd se projevuje u n\u011bkter\u00fdch krystalick\u00fdch materi\u00e1l\u016f, jako je k\u0159emen, turmal\u00edn, nebo syntetick\u00e9 materi\u00e1ly, nap\u0159\u00edklad titan\u00e1t barnat\u00fd (BaTiO\u2083) a zirkon\u00e1t olovnat\u00fd titan\u00e1t (PZT).  Tyto materi\u00e1ly, ozna\u010dovan\u00e9 jako piezoelektrick\u00e9, vykazuj\u00ed polarizaci krystalov\u00e9 m\u0159\u00ed\u017eky.  Kdy\u017e je na takov\u00fd materi\u00e1l aplikov\u00e1na mechanick\u00e1 s\u00edla (tlak, tah, vibrace), doch\u00e1z\u00ed k deformaci krystalov\u00e9 struktury a n\u00e1sledn\u00e9 zm\u011bn\u011b polarity. Tato zm\u011bna polarity indukuje elektrick\u00e9 nap\u011bt\u00ed na povrchu materi\u00e1lu.  Naopak, p\u0159i aplikaci elektrick\u00e9ho pole na piezoelektrick\u00fd materi\u00e1l doch\u00e1z\u00ed k jeho deformaci \u2013 tzv. inverzn\u00ed piezoelektrick\u00fd efekt.<\/p>\n<p>Materi\u00e1ly pou\u017e\u00edvan\u00e9 v piezoelektrick\u00fdch senzorech<\/p>\n<p>R\u016fzn\u00e9 materi\u00e1ly vykazuj\u00ed odli\u0161n\u00e9 piezoelektrick\u00e9 vlastnosti, kter\u00e9 ovliv\u0148uj\u00ed jejich vhodnost pro specifick\u00e9 aplikace.  N\u00e1sleduj\u00edc\u00ed tabulka shrnuje n\u011bkter\u00e9 b\u011b\u017en\u011b pou\u017e\u00edvan\u00e9 materi\u00e1ly:<\/p>\n<table class=\"table table-striped table-bordered\">\n<thead>\n<tr>\n<th>Materi\u00e1l<\/th>\n<th>Symbol<\/th>\n<th>Dielektrick\u00e1 konstanta<\/th>\n<th>Piezoelektrick\u00e1 konstanta<\/th>\n<th>Teplotn\u00ed stabilita<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>K\u0159emen<\/td>\n<td>SiO\u2082<\/td>\n<td>4.5<\/td>\n<td>2.3 pC\/N<\/td>\n<td>Vysok\u00e1<\/td>\n<\/tr>\n<tr>\n<td>Titan\u00e1t barnat\u00fd<\/td>\n<td>BaTiO\u2083<\/td>\n<td>1700<\/td>\n<td>190 pC\/N<\/td>\n<td>St\u0159edn\u00ed<\/td>\n<\/tr>\n<tr>\n<td>Zirkon\u00e1t olovnat\u00fd titan\u00e1t<\/td>\n<td>PZT<\/td>\n<td>1000-10000<\/td>\n<td>150-700 pC\/N<\/td>\n<td>St\u0159edn\u00ed a\u017e n\u00edzk\u00e1<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>Volba materi\u00e1lu z\u00e1vis\u00ed na po\u017eadovan\u00e9 citlivosti, frekven\u010dn\u00ed odezv\u011b, teplotn\u00ed stabilit\u011b a dal\u0161\u00edch faktorech.<\/p>\n<p>Konstrukce a typy piezoelektrick\u00fdch senzor\u016f<\/p>\n<p>Piezoelektrick\u00e9 senzory se vyr\u00e1b\u011bj\u00ed v r\u016fzn\u00fdch konfigurac\u00edch a velikostech v z\u00e1vislosti na zam\u00fd\u0161len\u00e9 aplikaci.  Nejb\u011b\u017en\u011bj\u0161\u00ed typy zahrnuj\u00ed:<\/p>\n<ul>\n<li><strong>Sn\u00edma\u010de tlaku:<\/strong>  Pou\u017e\u00edvaj\u00ed se k m\u011b\u0159en\u00ed tlaku plynu nebo kapaliny.<\/li>\n<li><strong>Akcelerometry:<\/strong> M\u011b\u0159\u00ed zrychlen\u00ed nebo vibrace.<\/li>\n<li><strong>Sn\u00edma\u010de s\u00edly:<\/strong> M\u011b\u0159\u00ed s\u00edlu aplikovanou na senzor.<\/li>\n<li><strong>Ultrazvukov\u00e9 senzory:<\/strong>  Generuj\u00ed a detekuj\u00ed ultrazvukov\u00e9 vlny.  V tomto p\u0159\u00edpad\u011b se vyu\u017e\u00edv\u00e1 inverzn\u00ed piezoelektrick\u00fd efekt k generov\u00e1n\u00ed vln a p\u0159\u00edm\u00fd efekt k jejich detekci.  P\u0159esn\u00e1 frekvence a charakteristiky z\u00e1vis\u00ed na aplikaci a pou\u017eit\u00e9m materi\u00e1lu.  Nap\u0159\u00edklad, pro m\u011b\u0159en\u00ed vzd\u00e1lenost\u00ed se b\u011b\u017en\u011b pou\u017e\u00edvaj\u00ed senzory s frekvenc\u00ed v rozsahu des\u00edtek kHz.<\/li>\n<\/ul>\n<p>Aplikace piezoelektrick\u00fdch senzor\u016f<\/p>\n<p>Piezoelektrick\u00e9 senzory nach\u00e1zej\u00ed \u0161irok\u00e9 uplatn\u011bn\u00ed v mnoha oblastech, v\u010detn\u011b:<\/p>\n<ul>\n<li><strong>Automatizace:<\/strong>  \u0158\u00edzen\u00ed pr\u016fmyslov\u00fdch proces\u016f, detekce vad.<\/li>\n<li><strong>Biomedic\u00edna:<\/strong>  M\u011b\u0159en\u00ed tlaku krve, ultrazvukov\u00e1 diagnostika.<\/li>\n<li><strong>Letectv\u00ed:<\/strong>  M\u011b\u0159en\u00ed vibrac\u00ed, detekce poruch.<\/li>\n<li><strong>Spot\u0159ebn\u00ed elektronika:<\/strong>  Zapalova\u010de, tla\u010d\u00edtka, sn\u00edma\u010de v dotykov\u00fdch displej\u00edch.<\/li>\n<\/ul>\n<p>Omezen\u00ed piezoelektrick\u00fdch senzor\u016f<\/p>\n<p>P\u0159es \u0161irokou \u0161k\u00e1lu aplikac\u00ed maj\u00ed piezoelektrick\u00e9 senzory i sv\u00e1 omezen\u00ed.  Mohou b\u00fdt citliv\u00e9 na teplotu a vlhkost, jejich odezva m\u016f\u017ee b\u00fdt neline\u00e1rn\u00ed a jejich \u017eivotnost m\u016f\u017ee b\u00fdt omezena st\u00e1rnut\u00edm materi\u00e1lu.  D\u00e1le, jejich citlivost m\u016f\u017ee b\u00fdt ovlivn\u011bna p\u0159\u00edtomnost\u00ed parazitn\u00edch kapacit.<\/p>\n<p>Piezoelektrick\u00e9 senzory p\u0159edstavuj\u00ed d\u016fle\u017eitou sou\u010d\u00e1st mnoha technologi\u00ed.  D\u00edky sv\u00e9 schopnosti p\u0159ev\u00e1d\u011bt mechanickou energii na energii elektrickou a naopak, nach\u00e1zej\u00ed \u0161irok\u00e9 uplatn\u011bn\u00ed v r\u016fzn\u00fdch oborech a neust\u00e1le se rozv\u00edj\u00ed jejich mo\u017enosti a aplikace.  Pochopen\u00ed jejich fungov\u00e1n\u00ed je kl\u00ed\u010dov\u00e9 pro efektivn\u00ed vyu\u017eit\u00ed jejich potenci\u00e1lu.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Piezoelektrick\u00e9 senzory jsou fascinuj\u00edc\u00ed za\u0159\u00edzen\u00ed, kter\u00e1 dok\u00e1\u017e\u00ed p\u0159ev\u00e1d\u011bt mechanickou energii na energii elektrickou a naopak. Tento princip, objeven\u00fd v roce 1880 Pierrem a Jacquesem Curie, nach\u00e1z\u00ed \u0161irok\u00e9 uplatn\u011bn\u00ed v mnoha oblastech modern\u00ed technologie. Tento \u010dl\u00e1nek se podrobn\u011bji zam\u011b\u0159\u00ed na princip fungov\u00e1n\u00ed t\u011bchto senzor\u016f a jejich specifick\u00e9 vlastnosti. Piezoelektrick\u00fd efekt: Z\u00e1kladn\u00ed princip Piezoelektrick\u00fd efekt je fyzik\u00e1ln\u00ed<\/p>\n","protected":false},"author":1,"featured_media":26464,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6415],"tags":[],"class_list":["post-61231","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-blog","prodpage-classic"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/www.bjultrasonic.com\/cs\/wp-json\/wp\/v2\/posts\/61231","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.bjultrasonic.com\/cs\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.bjultrasonic.com\/cs\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.bjultrasonic.com\/cs\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.bjultrasonic.com\/cs\/wp-json\/wp\/v2\/comments?post=61231"}],"version-history":[{"count":0,"href":"https:\/\/www.bjultrasonic.com\/cs\/wp-json\/wp\/v2\/posts\/61231\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.bjultrasonic.com\/cs\/wp-json\/wp\/v2\/media\/26464"}],"wp:attachment":[{"href":"https:\/\/www.bjultrasonic.com\/cs\/wp-json\/wp\/v2\/media?parent=61231"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.bjultrasonic.com\/cs\/wp-json\/wp\/v2\/categories?post=61231"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.bjultrasonic.com\/cs\/wp-json\/wp\/v2\/tags?post=61231"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}