To make more effective use of the circumference of arm rotation while assisting the arm rotation in terms of the rotatability of an arm that holds a camera head, resulting in a more compact device.The imaging device 100 holds a camera head 120 against a table 110 by means of a camera holding arm 140, and the camera holding arm 140 is axially supported rotatably so that the degree of incline relative to the table 110 is variable. A coil spring 260 is incorporated in a through hole 203b, as well as a recess 143k continuous therewith, about the axis of a first subaxial pin 220 aligned with the axis of the arm axial support. The coil spring 260 assists rotation by building up coil spring stress while the camera holding arm 140 (base 143) rotates toward the table 110, and by allowing the coil spring stress to be exerted in the form of assisting force on the arm when the base 143 rotates in such a way that the angle of incline with the table 110 expands.