Method and system for distinguishing fault of substrate

The invention relates to a system and a method for distinguishing a fault of a substrate. The system comprises at least one lighting unit, at least one first imaging unit, at least one second imaging unit, at least one image construction module and at least one image processing module, wherein the lighting units are arranged at the outer side of one surface of a transparent or semi-transparent substrate and used for irradiating light to the substrate; the first imaging units and the second imaging units are arranged at the outer sides of the other opposite surface of the substrate and respectively used for sensing the irradiation of the lighting units and transmitting the light passing through the substrate to shoot images, and the inclined angles between the optical axes of the first imaging units and the second imaging units are larger than zero; the image construction modules are used for respectively constructing two images of the substrate according to images shot by the first imaging units and the images shot by the second imaging units; and the image processing modules are used for detecting whether fault is on the surface of the substrate or in the substrate according to the correlation of the fault in the two constructed images when the substrate has fault. By utilizing the method and the system, the fault of the transparent or semi-transparent substrate can be distinguished to be on the surface of the substrate or in the substrate.