Patent ID: 7639303

Claim:
A method of lens auto-focusing in camera module test, comprising the following steps: providing testing equipment, wherein the testing equipment comprises a range finder, a signal processor and a driving member all connected electrically; providing an imaged object; providing an camera module comprising a lens and an image sensor, wherein a view angle and the biggest value of modulation transfer function of the lens module are both certain values; an image of the imaged object is formed in the image sensor; the imaged object and the image formed thereby in the other side of the lens module are fixed; inputting an initial image distance tested by the range finder into the signal processor, wherein the signal processor calculates the initial image height based on the initial image distance, and further calculates a displacement for the driving member using a linear equation: x=n(y−S 1 ), wherein x is the displacement of the driving member, y is the image height when the lens at focusing point, S 1 is the initial image height, n is equal to 1/tan θ, and θ is the view angle of the lens; and generating a controlling signal via the signal processor and sending the signal to the driving member to control it, driving the lens module to a focusing point via the driving member.