| 摘要 |
Apparatus for measurement of lung resistance includes a low voltage and high frequency power supply connected to a driver electrode contacting one side of a chest with a detector electrode contacting the opposite side of the chest and a pickup electrode engaging the chest therebetween. A variable resistor is connected with other resistors between the detector and pickup electrodes to form a bridge circuit with a portion of the lung resistance and a meter connected to the detector electrode indicates bridge balance whereat the resistance of the variable resistor is equal to the resistance of a portion of the lung. A guard ring about the detector electrode has segments thereof driven by operational amplifiers from the detector electrode to substantially eliminate skin potential gradients laterally of the detector.
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