This rotary drive apparatus is arranged to rotate a flywheel arranged to support an optical component arranged to reflect incoming light coming from a light source or allow the incoming light to pass therethrough, and includes a motor including a rotating portion; and the flywheel, the flywheel being supported by the motor and arranged to rotate about a central axis extending in a vertical direction. The flywheel includes a plate-shaped accommodating portion in which the optical component is arranged; a bottom surface arranged at a bottom portion of the accommodating portion, and arranged to slant with respect to at least one of two opposed side surfaces of the optical component; and a base surface arranged to be in contact with at least a portion of another one of the two opposed side surfaces of the optical component.