CAJ | 학술논문

中国计量科学研究院建立了标准不确定度为2×10-8的可动屏蔽型计算电容装置。该装置复现电容单位量值只与屏蔽电极所移动的轴向长度有关。采用激光干涉仪测量这个长度时，一般无法提供干涉条纹数。经典方法采用替换方法，逐步从已知的小整数扩大到大整数。过程复杂，所需条件多。提出了一种新的复现电容单位的方法。对应复现电容量值的干涉条纹整数由一个准确度等级相对较低的仪器直接确定。其干涉条纹小数则通过电容电桥的两次平衡确定。所需结构及过程简单，操作方便。给出了该方法的详细内容及其优点，报告了检查装置线性的实验及其结果。
중국계량과학연구원건립료표준불학정도위2×10-8적가동병폐형계산전용장치。해장치복현전용단위량치지여병폐전겁소이동적축향장도유관。채용격광간섭의측량저개장도시，일반무법제공간섭조문수。경전방법채용체환방법，축보종이지적소정수확대도대정수。과정복잡，소수조건다。제출료일충신적복현전용단위적방법。대응복현전용량치적간섭조문정수유일개준학도등급상대교저적의기직접학정。기간섭조문소수칙통과전용전교적량차평형학정。소수결구급과정간단，조작방편。급출료해방법적상세내용급기우점，보고료검사장치선성적실험급기결과。
A new type caIcuIabIe capacitOr with a mOvabIe guard rOd has been buiIt in NatiOnaI Institute Of MetrOIOgy Of China at the standard uncertainty Of 2 × 10-8 . The SI unit Of capacitance reprOduced by the caIcuIabIe capacitOr depends On the axiaI Iength which is measured by a Iaser interferOmeter. HOwever the huge integraI number Of the fringe is in generaI nOt given by the Iaser interferOmeter. In a cIassicaI apprOach the substitutiOn measurements were adOpted tO extend the integraI number frOm a knOwn smaIIer vaIue tO the bigger One. It needs sOme additive devices and cOmpIex OperatiOns. A nOveI apprOach is prOpOsed. The required integraI number is determined by the Other capacitance standard with a IOwer accuracy, and the decimaI number is determined by the capacitance bridge with a transfer capacitOr. The detaiIs Of this apprOach and its advantages are presented. An experiment tO check the Iinear is repOrted.