AIR ION SENSOR AND AIR ION GENERATING APPARATUS USING IT

PROBLEM TO BE SOLVED: To provide a compact and inexpensive air ion sensor capable of detecting air ions highly sensitively and stably, and an air ion generating apparatus using the sensor. SOLUTION: Negative ions are collected to a current collection electrode 1, and a charging capacitor C1 is charged with negative charge. When the voltage between the both ends of a discharge lamp 2 reaches a discharge inception voltage, the discharge lamp 2 discharges, and the charge and discharge are repeated thereafter. When a discharge pulse is applied to a voltage V2 through a coupling capacitor C2 by discharge from the discharge lamp 2 and by a subsequent voltage V1 change, a discharge waveform sensing shaping circuit 3 detects the discharge pulse and outputs a signal V3 having an elongated pulse width. A display annunciator circuit 4 lights a light emitting diode LED1 at the discharge detection time by the signal V3 outputted from the discharge waveform sensing and shaping circuit 3 and reports the existence of negative ions and the negative ion concentration by a lighting period. COPYRIGHT: (C)2004,JPO