A method for eliminating a ring effect is provided. The method includes: capturing, by a camera, a standard ring image generated by light illuminating a standard Fresnel lens; establishing a compensation lookup table according to the standard ring image and obtaining a standard ring center point; capturing, by the camera, a ring image generated by the light illuminating a Fresnel lens to be tested; obtaining a ring center point according to the ring image; obtaining a conversion relationship between the ring center point and the standard ring center point; and performing a compensation procedure on the ring image according to the compensation lookup table and the conversion relationship to eliminate the ring effect in the ring image.