Non-destructive online testing equipment used for measuring thickness of ink layer in mobile phone cover plate

The invention discloses non-destructive online testing equipment used for measuring thickness of an ink layer in a mobile phone cover plate. The non-destructive online testing equipment used for measuring the thickness of the ink layer in the mobile phone cover plate comprises a point light source, a cylindrical lens, a slit, a microscope objective, a doublet lens, a CCD camera and an image processing module, wherein the collimated light rays projected by the point light source form a diverging line light source by virtue of the cylindrical lens, and the line light source passes through the slit and the microscope objective and then is converged on the surface of a mobile phone cover plate to be measured and forms straight line light with high brightness and narrow width; and the long and fine straight line light passes through a region where the ink layer and a non-ink layer are intersected, and the microscope objective is focused on the intersected region, so that bending change degree of the straight line