Abstract: The invention relates to a radiation source including: an illuminant; a first optical element; and a sensor. The sensor is designed appropriately and is connected to the first optical element appropriately such that the sensor can be used to determine a change of a parameter of the first optical element over time, whereby the parameter affects an optical property of the radiation source. Moreover, the invention relates to a method for the producing a product involving the provision of a radiation source according to the invention as well as to a use of the radiation source to increase the efficiency of conversions or changes of state of educts to products.

Abstract: A device for hardening a coating on an inner wall of a conduit having an oval cross section has at least a first UV lamp, a second UV lamp, and a guide unit having a mount for each of the UV lamps. The guide unit defines the position of the UV lamps in relation to the oval cross section of the conduit, which has a first curved section, a second curved section opposite the first, and two lateral sections. To allow for universal use and the most uniform possible UV irradiation of the inner wall, a first reflector is allocated for guiding light emitted by the first UV lamp onto the first curved section, and a second reflector is allocated for guiding light emitted by the second UV lamp onto the second curved section. The first and second reflectors differ in their reflector angle and/or their coefficient of reflection.