TECHNOLOGY FOCUS - INSTRUMENTATION AND TESTING - Preferred Components: The device is adapted to control the lamination device considering the information about the state of crosslinking of the cross-linkable polymer material, which is determined by the evaluation unit. The heater comprises a heating plate, where the pressing device acts on one side of the heating plate and the illuminating device and the detection device are arranged on the opposite side of the heating plate. The heating plate has an opening, through which the illumination device illuminates the cross-linkable polymer material, which surrounds the objects placed in the pressing device, and the fluorescent light may pass back to the detection device. The lighting device comprises a light emitting diode and/or the detection device comprises a photodiode. The illumination device is constructed and arranged such that light emitted from the illumination device at an angle other than 90 degrees meets at a surface of the objects surrounding cross-linkable polymer material. A first filter is arranged in an optical path between the illuminating device and the lamination device to filter out light having a wavelength above a cut-off wavelength of 400 plus minus 50 nm, and a second filter is arranged in an optical path between the lamination device and the detection device, which filters out light having a wavelength below the cut-off wavelength.    TECHNOLOGY FOCUS - POLYMERS - Preferred Method: The steps (d)-(f) are carried out repeatedly during the heating of the cross-linkable polymeric material to more than 120 degrees C. The heating of the cross-linkable polymer material is terminated at 120 degrees C after an intensity of detected fluorescent light exceeds a threshold value. The steps (d)-(f) are carried out within a period of one week after terminating the heating of the cross-linkable polymer material and before exposing the cross-linkable polymer material to solar radiation or a similar strong UV source. An initial intensity is measured by fluorescent light before or during initiation of heating of the cross-linkable polymeric material to more than 120 degrees C, and an actual intensity is measured by fluorescent light during or after the heating, where the information about a state of crosslinking of the cross-linkable polymeric material is derived based on of a quotient of the actual intensity and the initial intensity. The cross-linkable polymer material is periodically illuminated in process step (d), and the fluorescent light is detected in the step (e) by a lock-in process. The cross-linkable polymer material is compressed and heated under oxygen deficiency, preferably under vacuum. EXAMPLE - No suitable example given.