| 摘要 |
PURPOSE:To correct and suppress temp. fluctuation during measurement and to measure exact absolute humidity by dividing and calculating the differentially amplified voltage by the voltage at the juncture of the balancing resistances of a bridge circuit and the voltage at the juncture of thermistors by the voltage at the juncture of the balancing resistances. CONSTITUTION:The voltage VC at the juncture of the balancing voltages forming a bridge circuit and the voltage VS at the juncture of a thermistor 1 for detecting humidity and a thermistor 2 for comparison are processed by a differential amplifier 8 and the voltage VO corresponding to the absolute humidity is generated. The voltages VC and VO are supplied to a control means 14' by which the voltages are subjected to A/D conversion then VC/VO is calculated. The temp. fluctuation is thus corrected and suppressed even if the voltage VB at the end of the bridge circuit to be connected to an electric power source changes. The absolute humidity is exactly measured even if the temp. fluctuates during measurement. |
