A donor element useful in an assemblage for imaging by exposure to light comprises a support layer formed by a stretching process, a light-to-heat conversion layer disposed adjacent the support layer containing a light absorber, and a transfer layer disposed adjacent the light-to-heat conversion layer opposite the support layer. This task is solved by a device for fluid feed for explosive forming that has a valve and an activating mechanism to activate the valve, in which the activating mechanism is arranged separate from the valve in an inactivated valve state. Respective guides support the rods for movement parallel to their axes, and a bar extends transversely between the outer ends. The laser beam is separated into a 0-th order laser beam and \xb1 primary laser beams, which are made incident on the objective lens, pass therethrough, and are made incident on the recording surface of a disk. They are useful in therapy, in particular in the management of pain.