Provided is a multi-channel near-infrared brain function measuring device that can easily level detector noise. In advance, the transmittance of all the optical attenuators is set to 1, and the maximum light amount that can safely irradiate all the light sources is set, and the effective incident light amount of each light source probe i, the minimum effective incident light amount and the maximum effective light amount among them. The incident light quantity is obtained, and the transmittance a i of the light attenuator i on the light source probe side is changed to [minimum effective incident light quantity / effective incident light quantity of the light source probe i] to equalize the effective incident light quantity. The intensity is changed to W = [maximum effective incident light quantity / minimum effective incident efficiency] times, the effective detection efficiency of the detector probe j and the minimum effective detection efficiency thereof are obtained, and the optical attenuator j on the detector probe side is obtained. Is changed to [minimum effective detection efficiency / effective detection efficiency of detector probe j] to control the effective detection efficiency to be equalized, and the detector noise between all the channels k is leveled. Near-infrared brain function measuring device was turned into.検出器雑音平準化が簡単な多チャンネル近赤外脳機能計測装置を提供する。 予め、すべての光減衰器の透過率を１に設定しすべての光源強度を安全に照射し得る最大光量に設定して各光源プローブｉの実効入射光量とそのうち最小の実効入射光量および最大の実効入射光量を求め、光源プローブ側の光減衰器ｉの透過率ａiを、［最小の実効入射光量／光源プローブｉの実効入射光量］に変更することにより実効入射光量を平準化し、さらにすべての光源強度をＷ＝［最大の実効入射光量／最小の実効入射効率］倍に変更し、検出器プローブｊの実効検出効率とそのうちの最小の実効検出効率を求め、検出器プローブ側の光減衰器ｊの透過率ａjを、［最小の実効検出効率／検出器プローブｊの実効検出効率］に変更することにより実効検出効率を平準化しておくよう制御してすべてのチャンネルｋ間の検出器雑音を平準化した近赤外脳機能計測装置。
