公开(公告)号：US5264798A

公开(公告)日：1993-11-23

申请号：US783904

申请日：1991-10-29

申请人： Paul P. Bey, Jr. ,  Thomas L. Fare

发明人： Paul P. Bey, Jr. ,  Thomas L. Fare

IPC分类号： G01N27/02 ,  G01R17/06

CPC分类号： G01R17/06 ,  G01N27/028

摘要： A self-contained autonulling bridge circuit based on phase-sensitive deteon of an impedance to be measured is described. The system utilizes a feedback structure to control a variable impedance in order to establish the null of the bridge. The system utilizes a voltage-variable impedance having both resistance and capacitance and provides the phase sensitive relationship in the control means in order to provide highly accurate measurement of an unknown test impedance. The ability to measure small changes in impedance provides particularly useful application to the area of biological sensor impedance measurement or electrochemical impedance measurement using silicon-based devices.

摘要翻译： 描述了一种基于待测量阻抗的相敏检测的独立自适应桥接电路。 该系统利用反馈结构来控制可变阻抗，以建立桥的零点。 该系统利用具有电阻和电容两者的电压可变阻抗，并在控制装置中提供相位敏感关系，以便提供未知测试阻抗的高精度测量。 测量阻抗变化小的能力为使用硅基器件的生物传感器阻抗测量或电化学阻抗测量领域提供了特别有用的应用。

公开(公告)号：US4194838A

公开(公告)日：1980-03-25

申请号：US764894

申请日：1977-02-22

申请人： Michael P. Bey ,  Paul P. Bey

发明人： Michael P. Bey ,  Paul P. Bey

IPC分类号： G03B27/73 ,  G01J3/50

CPC分类号： G03B27/735

摘要： A photometric device for measuring and displaying by digital means primary color densities of a color negative to be printed to determine densities of color compensating filters. Exposure time, including reciprocity effect compensation for the photographic paper, is displayed digitally and determined by density measurements of the projected image.A reference area of a color negative illuminated by light through color compensating filters is projected on the aperture of a probe which directs light through a light guide to a photodetector. The resulting photocurrents generate voltages amplified by a first and second variable gain linear amplifier. The second amplifier provides primary color and exposure density reference by means of gains stored by measurement of a standard negative. Digital display means is provided to display memory gains for accurately modifying or resetting reference gains. The output of the second amplifier is coupled to a signal integrator alternately gated by a pulse generator and an exposure-time controlled integrator. A voltage comparator and digital circuitry coupled to the signal integrator serve to display the density of color compensation negative optical density representative of a particular print reflectivity.The exposure-time integrator is coupled to a voltage comparator which gates digital counters to display exposure time including compensation for reciprocity effects. An alternative exposure-time circuit utilizes analog means to display exposure time.

摘要翻译： 用于通过数字测量和显示的测光装置意味着要打印的彩色负片的原色浓度以确定颜色补偿滤光片的密度。 曝光时间，包括相纸的互惠效果补偿，以数字方式显示，并由投影图像的浓度测量确定。 通过颜色补偿滤光器照明的由彩色负片照射的彩色负参考区域投射在探针的孔上，该探针将光引导通过光电检测器。 所产生的光电流产生由第一和第二可变增益线性放大器放大的电压。 第二个放大器通过测量标准负极存储的增益提供原色和曝光浓度参考。 提供数字显示装置以显示存储器增益，以准确地修改或重置参考增益。 第二放大器的输出耦合到由脉冲发生器和曝光时间控制的积分器交替门控的信号积分器。 耦合到信号积分器的电压比较器和数字电路用于显示代表特定打印反射率的色彩补偿负光密度的密度。 曝光时间积分器耦合到电压比较器，门控数字计数器以显示曝光时间，包括对互惠效应的补偿。 另一种曝光时间电路利用模拟装置来显示曝光时间。