Device for controlling a stepper motor that drives one or more camera elements

摘要

A device for controlling a stepper motor that drives a plurality of shutter blades. The movement and position of the movement of the rotor of the stepper motor is monitored to determine when the next step of the stepper motor should be stepped so that the rotation of the rotor will be known to cause the shutter blades to form the correct aperture size. The device may also be used to drive an automatic focusing mechanism and/or zoom.