公开(公告)号：US4620148A

公开(公告)日：1986-10-28

申请号：US644242

申请日：1984-08-27

申请人： Arthur L. Davison ,  Martin D. Blackburn ,  Donald A. Sellek

发明人： Arthur L. Davison ,  Martin D. Blackburn ,  Donald A. Sellek

IPC分类号： G01J3/28 ,  G01J3/36 ,  G01R19/00 ,  G01R19/255 ,  G01R17/06 ,  G01R19/26 ,  H03K13/02

CPC分类号： G01R19/0092 ,  G01J3/36 ,  G01R19/0023 ,  G01R19/255 ,  G01J2003/2836

摘要： A precision current meter of wide dynamic range and sensitivity to low currents is disclosed. The precision current meter is particularly useful as a component for spectrochemical computations in spectrometers for the simultaneous multielement analysis of unknown samples in solution. The precision current meter comprises a source of input current, preferably a photomultiplier tube, an integrator having an integrating capacity for detecting the input current from the source, a source of reference currents including an offset current, a switch with a drain current coupled to the integrator. A clock is provided for generating clock signals for the current meter, including a series of pulses to actuate the switch and thereby to admit drain current segments to the integrator. A first counter is coupled to the output of the integrator to count the number of the series of actuating pulses during a predetermined time interval, and a second counter coupled to both the integrator output and the clock fixes the predetermined time interval. Preferably, both the integrator output and the switch are coupled via optical couplers to the counters.

摘要翻译： 公开了一种具有宽动态范围和对低电流灵敏度的精密电流表。 精密电流表特别适用于光谱仪中用于分析溶液中未知样品的同时多元素分析的光谱化学计算的组件。 精密电流表包括输入电流源，优选光电倍增管，具有用于检测来自源极的输入电流的积分能力的积分器，包括偏移电流的参考电流源，与漏极电流耦合的开关 集成商 提供用于产生电流表的时钟信号的时钟，包括用于致动开关的一系列脉冲，从而允许漏极电流段接收到积分器。 第一计数器耦合到积分器的输出以在预定时间间隔内对一系列致动脉冲的数量进行计数，并且耦合到积分器输出和时钟两者的第二计数器固定预定时间间隔。 优选地，积分器输出和开关都经由光耦合器耦合到计数器。