US Patent 7826737 Image pickup apparatus and focusing method thereof

An imaging pickup apparatus includes a lens module and a motor. The body includes a camera module configured for sensing an image. The motor is configured for driving the lens module to move in increments that are multiple steps of the motor. The multiplier used are “x” and “y” during an auto focus process. The image pickup apparatus includes a preset step number. Initially, the motor drives the lens module to move by increments of “x” steps. When the number of steps moved by the motor is greater than or equal to the preset step number, the motor drives the lens module to move by increment of “y” steps.