BRUSHLESS DC MOTOR AND IMAGE PICKUP APPARATUS

摘要

A BLDC(Brushless DC) motor and an image pickup device are provided to reduce the speed variation of a driven member by changing a lead angle according to the position and the moving direction of the driven member. A rotor(21) has a magnet. A stator(22) has a coil. The coil provides the rotation force to the magnet. A first position detector(15) and a second position detector(16) output a first signal periodically according to the rotation position of a rotor. A signal generator(8) generates a second signal by adding the lead angle to the phase of the first signal outputted from the first and second position detectors. An excitation switch(7) selects the excitation of the coil according to the second signal. The phase shift part changes the lead angel according to at least one of the position and the moving direction of the driven member.