Testing chart, camera module testing system and camera module testing method

A camera module testing method includes the following steps:

• providing a testing chart, the testing chart comprising a scaleboard, a testing pattern printed on the scaleboard and at least four marks formed on the scaleboard, each quadrant of a rectangular coordinate system with an origin thereof meeting a geometric center of the testing chart being distributed with at least one of the marks;
• providing a camera module, the camera module comprising a focusing lens and a voice coil motor configured to drive the focusing lens to move along an optical axis of the camera module;
• positioning the testing chart at an object side of the camera module, and make the geometric center of the testing chart located in the optical axis of the camera module;
• driving the focusing lens to capture images of the testing chart;
• and
• providing a processor, during a focusing process of the camera module, according to a position of a polygon formed by the at least four marks relative to the image sensing center of the camera module, the processor calculating a horizontal offset of the voice coil motor.