According to an embodiment of the present invention, an optical signal measuring module comprises: a cover substrate including one surface and the other surface, and including a through hole penetrating the one surface and the other surface； a first light reflection unit arranged on the inner side surface of the through hole； a second light reflection unit extended from the first light reflection unit and partially arranged on the other surface of the cover substrate； a third light reflection unit extended from the first light reflection unit and partially arranged on one surface of the cover substrate； a light receiving unit partially arranged on the other surface of the cover substrate while being separated from the second light reflection unit； and a light emitting unit arranged in a region corresponding to the through hole. According to an embodiment of the present invention, an optical signal sensing apparatus comprises: a cover substrate including one surface and the other surface, and including a through hole penetrating the one surface and the other surface； a first light reflection unit arranged on the inner side surface of the through hole； a second light reflection unit extended from the first light reflection unit and arranged on the other surface of the cover substrate； a third light reflection unit extended from the first light reflection unit and arranged on one surface of the cover substrate； a light receiving unit arranged on the other surface of the cover substrate directly； a substrate arranged to face the cover substrate； and a light emitting unit arranged between the other surface of the cover substrate and the substrate and having a width smaller than the width of the through hole. An accurate optical signal can be detected even at low power.COPYRIGHT KIPO 2018실시예에 따른 광 신호 측정 모듈은 일면 및 타면을 포함하고, 상기 일면 및 상기 타면을 관통하는 관통홀을 포함하는 커버 기판； 상기 관통홀의 내측면에 배치되는 제 1 광반사부； 상기 제 1 광반사부로부터 연장되어 상기 커버 기판의 타면 상에 부분적으로 배치되는 제 2 광반사부； 상기 제 1 광반사부로부터 연장되어 상기 커버 기판의
