Detects camera shake using a vibration gyro and corrects it by moving the optical element (2nd group) in the opposite direction of the shake to cancel out image blur.
The image stabilization effect is equivalent to 2 stops of shutter speed, meaning blur from a photo taken at 1/30 sec is suppressed to the same level as one taken at 1/125 sec.
Uses a micro USM for AF drive, achieving silent AF.
