In order to suppress an increase in parallax, suppress the oblique incidence of light rays on an image pickup element, and obtain a vivid image, this image pickup device (1) is provided with an image forming optical system (2) that forms two images having parallax and an image pickup element (3) that picks up a parallax image. The image forming optical system (2) is provided with the following: a first negative lens group (4) having a negative refractive power； a first positive lens group (5) having a positive refractive power； and a second positive lens group (6) having a positive refractive power. The first negative lens group (4) is provided with two negative lens groups (7, 8) that are disposed side-by-side in the parallax direction and that each have a center axis. The first positive lens group (5) is a common lens group that has a single center axis and that allows to pass therethrough the light emitted from each negative lens group (7, 8). The second positive lens group (6) is provided with two positive lens groups (13, 14) that are disposed side-by-side in the parallax direction and that each have a center axis. The first positive lens group (5) is provided with a moveable lens group that moves along the center axis of the positive lens group (5).La présente invention concerne, afin de supprimer une augmentation de parallaxe, de supprimer l'incidence oblique de rayons lumineux sur un élément de capture d'image et d'obtenir une image vive, un dispositif de capture d'image (1) doté d'un système optique de formation d'image (2) qui forme deux images présentant une parallaxe et d'un élément de capture d'image (3) qui capture une image parallaxe. Le système optique de formation d'image (2) est doté des éléments suivants : un premier groupe de lentilles négatives (4) ayant une puissance de réfraction négative ； un premier groupe de lentilles positives (5) ayant une puissance de réfraction positive ； et un second groupe de lentilles positives (6) ayant une puissanc
