Abstract: The manufacturing of at least one photothermal converter element according to the invention consists essentially of implanting a multiplicity of substantially uniformly distributed parallely projecting transparent fibers onto a baseplate element provided with an absorbing coating of a normally solid material capable of being temporarily converted to a plastic state, thanks to the use of an array of guiding means arranged above the baseplate element. The implantation proper of the desired fiber structure is then performed by advancing a series of bundles of fibers through the array of guiding means, to the desired level above the baseplate element, and by clipping the advanced bundles to the desired length above the guiding means, so as to cause the falling with limited transverse spreading of the clipped fibers onto the coating of the baseplate element.