An insertion section 21 to be inserted into the subject, a variable focus objective optical system 41 and a fixed focus objective optical system 51 disposed in the distal end portion 22 of the insertion section 21, an imaging section 61 for capturing an optical image, and a variable When the focal lengths of the focus objective optical system 41 and the fixed focus objective optical system 51 are different from each other, an in-subject image acquired by the variable focus objective optical system 41 is output as an image signal, and the fixed focus objective optical system 41 and the fixed focus objective optical system 41 are fixed. When the focal lengths of the focal objective optical system 51 match, the variable focal objective optical system 41 and an image signal generation / output unit 94 that outputs the in-subject image acquired by the fixed focal objective optical system 51 as an image signal are provided. .被検体内に挿入される挿入部２１と、挿入部２１の先端部２２内に配置される可変焦点対物光学系４１と固定焦点対物光学系５１と、光学像を撮像する撮像部６１と、可変焦点対物光学系４１と固定焦点対物光学系５１の焦点距離が互いに異なる場合は、可変焦点対物光学系４１により取得される被検体内像を画像信号として出力し、可変焦点対物光学系４１と固定焦点対物光学系５１の焦点距離が一致する場合は、可変焦点対物光学系４１と固定焦点対物光学系５１により取得される被検体内像を画像信号として出力する画像信号生成出力部９４とを備える。
