Fluorescent patterns with submicron dimensions have been obtained by creating stable F3+ and F2 color centers in LiF films using a focused x-ray beam provided at the ELETTRA synchrotron radiation facility. The patterns were written by scanning the LiF specimen with respect to the x-ray microprobe. In these attempts, using an x-ray microspot with a diameter of 100 nm and a flux density ⩾109 photons/s, we generated ∼500-nm-wide lines efficiently emitting in the visible spectral region when excited by blue light at 458 nm. Preliminary results indicate that the spectral distribution of the emitted luminescence can be changed by varying the photon dose delivered to the sample.