How does the repair / refurbishment work? 

When processing glass surfaces, a distinction is made between additives and subtractive processes.

 

In the additive process, damage to the glass surface is filled with resin, hardened and then polished. 

In the subtractive process, on the other hand, a minimal removal of the material (glass) takes place. The glass surface is removed over a minimal area until an intact glass surface is achieved.

The predetermined breaking point (scratches) in the glass caused by damage is thus removed and the homogeneous stress distribution, as in the origin of the pane, is restored. 

Finally, further grinding and polishing achieve the complete and unclouded transparency of the glass surface.