A styrene copolymer of 4-vinylbenzyl thiocyanate (PST-co-VBT) was employed as recording material for optical interference patterns with periods Λ < 1 μm. Using lower intensity laser irradiation (4 mJ cm-2, λ = 266 nm), refractive index gratings were produced in PST-co-VBT by an UV-induced photoisomerization SCN → NCS. Subsequent modification of the patterns with gaseous amines yielded surface relief gratings via the formation of derivatives of thiourea. Laser irradiation with higher pulse energies (7 mJ cm-2, λ = 266 nm) directly produced surface relief gratings via laser ablation (modulation depth 30 nm). Also these gratings were reactive toward amine reagents and allowed a selective functionalization of the grooves of the relief (“reactive gratings”). Under selected conditions, a doubling of the grating frequency was achieved by postexposure modification with gaseous amines. Optically inscribed gratings in PST-co-VBT were employed as optical resonators for distributed feedback (DFB) lasing. With a laser...