Abstract: A substrate is coated with a multilayer structure which has layers of a first portion and layers of a second portion that are deposited on the layers of the first portion. During the deposition of at least one layer of the second portion, at least one optical measuring apparatus measures an emissivity value and a reflectance value on the broad side of the substrate, which broad side comprises the layer. Using a previously determined correction value, an actual value of a temperature of the broad side of the substrate is calculated and, using the actual value, a heating apparatus is controlled in order to control the temperature of the substrate to match a target value of the temperature of the broad side of the substrate. The correction value is determined during the deposition of the first portion, which is carried out immediately before the deposition of the second portion.

Abstract: A method for coating a substrate with at least one layer. During deposition of the layer, at least one optical measuring device repeatedly determines successive measurement value pairs on the layer, each containing an emission value corresponding to the radiation power measured at a light wavelength and a reflectance value, which is also measured at a light wavelength. Actual values of a substrate temperature are calculated based on the measurement value pairs and a previously determined correction value. The actual values are used to control a temperature-control device for controlling the substrate temperature to a desired value. To improve the determination of the correction factor, during the measurement and within a plurality of measurement intervals, at least two measurement value pairs are measured and, for each of the measurement intervals, a temperature-dependent factor is determined that is used for the calculation of the correction value.

Abstract: A substrate is coated with a multilayer structure which has layers of a first portion and layers of a second portion that are deposited on the layers of the first portion. During the deposition of at least one layer of the second portion, at least one optical measuring apparatus measures an emissivity value and a reflectance value on the broad side of the substrate, which broad side comprises the layer. Using a previously determined correction value, an actual value of a temperature of the broad side of the substrate is calculated and, using the actual value, a heating apparatus is controlled in order to control the temperature of the substrate to match a target value of the temperature of the broad side of the substrate. The correction value is determined during the deposition of the first portion, which is carried out immediately before the deposition of the second portion.