全自动临床检验仪器中液面探测技术的进展

The Development of Techniques for Liquid Level Detection in Auto Clinical Laboratory Analyzers

液面探测(LLD)是全自动临床检验仪器必不可少的功能,其主要作用是控制移液针探入被移液体的深度,最大限度减少移液针外表面的液体携带量。本文归纳了不同情况下对LLD技术的不同要求;总结接触式中电阻法、电容法、气压法、机械振动法和非接触式中超声波法、光反射法、CCD成像法等LLD技术的工作原理和特点;归纳了LLD技术的发展趋势并对下一代LLD技术做了展望。

Liquid level detection（LLD） is necessary for eliminating carry-over of needle＇s outside by limiting the depth the needle probes into liquid in auto clinical laboratory analyzers.This paper listed various demands of liquidhandling system under different situations;reviewed various LLD techniques,such as capacitive,air pressure,mechanical vibration,ultrasound,light reflection,CCD imaging etc.;briefly introduced the working principles,features,and limitation of the LLDs;and recapitulated the characteristics of contact and noncontact LLDs.Lastly,the next generation technique of LLD is prospected.