Abstract: A thermal treatment unit for a printer is mountable on a carriage that moves across a printing medium. The thermal treatment unit comprises an emitter element to emit radiation towards the printing medium to thermally treat the printing medium, wherein the thermal treatment unit varies a radiation power output of the emitter element in terms of a spatial position of the carriage along a width direction of the printing medium.

Abstract: A method of cutting or scoring a substrate comprises: providing a substrate which has a maximum of radiation absorption at a first wavelength band; depositing on the substrate, in a predetermined pattern, a heating fluid which has a maximum of radiation absorption at a second wavelength band; and exposing a surface region of the substrate to electromagnetic radiation at the second wavelength band, the surface region including the predetermined pattern, to cut or mark the substrate along the predetermined pattern. The first wavelength band differs from the second wavelength band.