The living body information processing equipment detects the acoustic wave 16 which, is generated the illuminant due to the fact that light absorption body 15 inside 11 where light 12 is irradiated to the optical lighting field 13A on suffering inspection body 13 and suffering inspection body 13 absorbs light the signal processor 19 which obtains the information of the suffering inspection internal section on the basis of the signal which is amplified by the electronic control system 18 which possesses the amplifier which amplifies the detection signal which is output from the acoustic wave detector 17 which outputs the detection signal and acoustic wave detector 17 and the amplifier, and, has. Electronic control system 18 in order the gain for the detection signal of the acoustic wave where is generated 1st at position of suffering inspection internal, to become large in comparison with the gain for the detection signal of the acoustic wave which is generated at the 2nd position to which 1st exists in the vicinity of optical lighting field than position, controls the gain of the amplifier.生体情報処理装置は、被検体13上の光照射領域13Aに光12を照射する光源11と、被検体13内の光吸収体15が光を吸収することによって発生する音響波16を検出し、検出信号を出力する音響波検出器17と、音響波検出器17から出力される検出信号を増幅する増幅器を有する電子制御システム18と、増幅器により増幅された信号に基づき、被検体内部の情報を得る信号処理装置19と、を備える。電子制御システム18は、被検体内の第1の位置で発生した音響波の検出信号に対する利得が、第1の位置よりも光照射領域の近くに存在する第2の位置で発生した音響波の検出信号に対する利得に比べて大きくなるように、増幅器の利得を制御する。
