The optical measuring system 1 and a portable light measuring device 40 and the main optical measuring device 10, a second housing 41 to be portable to the subject, the portable light measuring device 40, the subject a second light transmitting means 12 of the number C to be irradiated with light, the second light-receiving means 13, D, of which receives light emitted from the subject, are mounted on the head of the subject, at least (C + D) By controlling the second holder 60 through holes of the individual is provided, the second light-receiving means 13 and 12 the second light-transmitting means, a control unit 51 obtains measurement data relating to brain activity, the main light measuring device 10 and a communication unit 46 is able to communicate, satisfied (C + D)> a (A + B), the communication unit 46 of the portable light measuring device 40 is obtained by the control unit 51 of the portable light measuring device 40 and characterized in that it is transmitted to the main optical measuring device 10 and the measured data.主光計測装置10と携帯型光計測装置40とを備える光計測システム1であって、携帯型光計測装置40は、被検者に携帯可能となる第二筐体41と、被検者に光を照射するC個の第2送光手段12と、被検者から放出される光を受光するD個の第2受光手段13と、被検者の頭部に装着され、少なくとも(C+D)個の貫通孔が設けられた第二ホルダ60と、第2送光手段12及び第2受光手段13を制御することで、脳活動に関する測定データを得る制御部51と、主光計測装置10と通信することが可能である通信部46とを備え、(C+D)>(A+B)を満足し、携帯型光計測装置40の通信部46は、携帯型光計測装置40の制御部51で得られた測定データを主光計測装置10に送信することを特徴とする。
