An optical transmission unit 25 that converts the image signal generated by the imaging unit 24 into an optical signal, and an optical transmission unit 25 that converts the optical signal converted by the optical transmission unit 25 into a first optical signal and a second optical signal at a predetermined light amount ratio The splitting unit 28 for splitting, the light amount information of the first light signal received by the light receiving unit 34 via the optical cables 27 b, 39 a and the optical connecting units 30 a, 31 a and the electric signal obtained by converting the second light signal An abnormality detection unit 35 for detecting whether there is an abnormality in the optical connection units 30a, 31a, based on the light intensity information of the first optical signal included in the electric signals transmitted from the electric cables 27c, 39b,撮像部24が生成した画像信号を光信号に変換する光送信部25と、光送信部25が変換した光信号を、所定の光量比で、第1の光信号と第2の光信号とに分割する分割部28と、光ケーブル27b,39aおよび光接続部30a,31aを介して光受信部34が受信した第1の光信号の光量情報と、第2の光信号が変換された電気信号であって電気ケーブル27c,39bが伝送した電気信号に含まれる第2の光信号の光量情報とに基づいて、光接続部30a,31aに異常があるか否かを検出する異常検出部35と、を備える。
