LIGHT DETECTION MODULE AND LIGHT DETECTION DEVICE

A light detection module having a light source emitting excitation lights to a sample a beam splitter reflecting the excitation lights toward an input and output port, and transmitting inspection lights the sample via the input and output port a light receiving element receiving the inspection lights and a housing containing the beam splitter and having a first opening installing the light source, and propagating the excitation lights a second opening corresponding to the input and output port a third opening installing the light receiving element and a fourth opening guiding a stray light transmitted the beam splitter reflecting, wherein the first, second, third and fourth opening communicate with each other at the position of the beam splitter, and the fourth opening extends in a direction perpendicular to the reflecting surface of the beam splitter.