B44F1/00—Designs or pictures characterised by special or unusual light effects
B44F1/02—Designs or pictures characterised by special or unusual light effects produced by reflected light, e.g. matt surfaces, lustrous surfaces
B44F1/04—Designs or pictures characterised by special or unusual light effects produced by reflected light, e.g. matt surfaces, lustrous surfaces after passage through surface layers, e.g. pictures with mirrors on the back