检测LCM对数字万用表准确度的要求

A Requirement of Digital Multimeters' Accuracy for Inspecting Liquid Crystal Modules

测量是质量检验工作的重要组成部分。通过测量可以确定被测量的大小,为质量检验、合格判定提供数据支持。用于测量的测量仪器在其中扮演着重要角色。没有它测量无法进行。但有了它,测量也不见得就可以进行。因为测量仪器有分辨率、准确度之分,不恰当的分辨率、准确度,同样无法准确测量被测量的大小,如果用于测量,反而会因为误测误导使用者作出错误的判定。在液晶显示行业,用于检测液晶显示模组(LCM)的数字万用表,如果选用不当,同样有此隐患。因此选用合适的数字万用表用于LCM检测显得尤其重要。本文侧重分析不同准确度万用表对测量结果的影响,并根据目前LCM行业内对产品设计公差的要求,推算在驱动电压、功耗电流、内阻的检测上对数字万用表准确度的要求,为LCM行业内数字万用表的选用提供参考。

Measuring is an important constitutional part of quality inspection. It can confirm size and provide data supports for inspection and judgement about eligibility. In measuring, the instrument used is very important. Without it, the measuring cann＇t be carried into execution. But it is also possible even though the instrument is at hand. Because instruments are distinguished by resolutions and accuracy grades. The size cann＇t be measured exactly by the instruments with inadequate precisions and accuracies. Otherwise the measurer will make a wrong judgement by measuring. Therefore it is particularly important to choose a proper instrument for measuring, such as the digital multimeter used for inspecting liquid crystal modules.This article lays emphasis on the analysis about the difference of influence by multimeters with different precisions and accuracies ,and calculates the necessary accuracy of the digital multimeter for inspecting liquid crystal modules, according to present designed tolerances of driving voltages, current consumptions and resistances. It will offer a reference for the choice of digital multimeters.