Patent ID: 7796875

Claim:
A focusing system for enhancing resolution of an optical system, the focusing system comprising: a lens assembly comprising an auto focusing (AF) lens configured for focusing on an object to obtain an image of the object; a digital signal processor comprising a calculating module configured for using a designated point within a motion range of the AF lens to calculate and determine a first coordinate of the AF lens at which point the AF lens obtains a desired sagittal modulation transfer function (MTF) and a second coordinate of the AF lens at which point the AF lens obtains a desired meridional MTF according to resolution of the image, and for ascertaining a direction and distance of motion for positioning the AF lens according to the two coordinates; and a motor driver connected with a motor, and configured for driving the motor to control the AF lens to move along the direction of motion and for limiting the range of motion of the AF lens to obtain an optimum focusing location to focus on the object according to the distance of motion.