CONTACT RESISTANCE DETECTOR

PROBLEM TO BE SOLVED: To simply detect contact resistance between a measurement subject's scalp and a brain wave measuring electrode.SOLUTION: A contact resistance detector takes in a voltage drop detection signal Va generated at each of contact resistances Ra11 to Ra16 between a plurality of brain wave measuring electrodes CH1 to CH6 and a scalp 2X by individually supplying constant currents ia11 to ia16 to which different frequencies 24[Hz] to 34[Hz] are allocated to the brain wave measuring electrodes CH1 to CH6 during the same processing section T1; and extracts a voltage drop detection signal component of each of the brain wave measuring electrodes CH1 to CH6 on the basis of the allocated frequencies 24[Hz] to 34[Hz], making it possible to detect the contact resistances Ra11 to Ra16 with respect to the plurality of brain wave measuring electrodes CH1 to CH6 in a lump during the same processing section T1. Thereby, the contact resistances Ra11 to Ra16 of the plurality of brain wave measuring electrodes CH1 to CH6 can be simply detected in a unit time.SELECTED DRAWING: Figure 8 【課題】測定対象者の頭皮と脳波測定電極との間の接触抵抗を簡便に検出する。【解決手段】同じ処理区間Ｔ１の間に、複数の脳波測定電極ＣＨ１〜ＣＨ６に対して異なる周波数２４[Ｈｚ]〜３４[Ｈｚ]が割り当てられた定電流ｉａ１１〜ｉａ１６をそれぞれ供給することにより当該脳波測定電極ＣＨ１〜ＣＨ６と頭皮２Ｘとの間の接触抵抗Ｒａ１１〜Ｒａ１６にそれぞれ生ずる電圧降下検出信号Ｖａを取り込むと共に、当該割り当てられた周波数２４[Ｈｚ]〜３４[Ｈｚ]に基づいて各脳波測定電極ＣＨ１〜ＣＨ６の電圧降下検出信号成分を抽出することにより、当該同じ処理区間Ｔ１の間に一挙に複数の脳波測定電極ＣＨ１〜ＣＨ６ごとの接触抵抗Ｒａ１１〜Ｒａ１６を検出することができ、これにより単時間の間に簡便に複数の脳波測定電極ＣＨ１〜ＣＨ６の接触抵抗Ｒａ１１〜Ｒａ１６を検出することができる。【選択図】図８