Device and method for detecting defects in liquid crystal substrate box

The invention, which belongs to the technical field of liquid crystal substrate quality detection, discloses a device and method for detecting defects in a liquid crystal substrate box. The detectingdevice comprises an inspection bench, a light source assembly, a first polarizing assembly, a to-be-detected substrate and a second polarizing assembly. The first polarizing assembly includes white glass and a first polaroid attached to the white glass. The second polarizing assembly includes white glass and a second polaroid attached to the white glass. The polarization direction of the first polaroid is perpendicular to that of the second polaroid; two surfaces of the to-be-detected substrate are in contact with the white glass; an ocular lens is arranged above the second polarizing assembly. The device has the following beneficial effects: the two polaroids having the polarization directions are perpendicular to each other are used for filtering light transmitted by the to-be-detected substrate; whether a defec