A living body information imaging apparatus includes a member that is adapted to be introduced into the interior of a living body and has a light irradiation portion for irradiating light the interior of the body with light with an angle of irradiation equal to or more than 2π steradians, and a signal detector that is arranged outside the living body and detects a signal output based on light irradiation in the interior of the living body by the member having the light irradiation portion.
