The present invention relate to UV-curing-compatible photochromic simply- and doubly-fused naphthopyrans according to general formulae (I) or (II) and to the use thereof in plastics of every kind, in particular for ophthalmic purposes. The photochromic compounds according to the invention are characterised by their outstanding UV-curing compatibility, i.e. they remain - when placed, for example, into an acrylate monomer matrix with a UV-initiator - undamaged after radical polymerisation of the matrix triggered by strong UV-light. With a suitable substituent selection, the photochromic colorants according to the invention are further characterised by two pronounced absorption bands of the open form in the visible wavelength region, i.e. with such a molecule two conventional photochromic colorants - each comprising a discrete absorption band - can be substituted.