PROBLEM TO BE SOLVED: To reduce the scale of a light detector that detects light radiated to a measured body and a reference body.SOLUTION: A light detector comprises: a Fabry-Perot spectroscopic element a first optical system that guides light radiated to a measured body and light radiated to a reference body to the spectroscopic element a first light receiving part and a second light receiving part that generate detection signals according to the intensity of received light and a second optical system that guides the light radiated to the measured body and divided by the spectroscopic element to the first light receiving part, and guides the light radiated to the reference body and divided by the spectroscopic element to the second light receiving part.SELECTED DRAWING: Figure 2COPYRIGHT: (C)2019,JPO&INPIT【課題】被測定体および参照体に照射された光を検出する光検出装置の規模を縮小する。【解決手段】ファブリペロー型の分光素子と、被測定体に照射された光と参照体に照射された光とを前記分光素子に導く第1光学系と、受光強度に応じた検出信号を生成する第1受光部および第2受光部と、前記被測定体に照射されて前記分光素子により分光された光を前記第1受光部に導き、前記参照体に照射されて前記分光素子により分光された光を前記第2受光部に導く第2光学系とを具備する光検出装置。【選択図】図2
