Abstract: In a method for the online determination of at least one rolling parameter when rolling a rolling material rolled along a rolling line in a rolling mill including at least two rolls on a roll stand, the rolling material is guided past or through at least one measuring device during the rolling, which interacts with a rolling material variable of the rolling material, the rolling material variable being changeable along the length of the rolling material, and outputs a measurement signal, wherein: (i) the measurement signal is transferred into the frequency space, and the rolling parameter is determined from the measurement signal transferred into the frequency space, and/or (ii) a frequency inherent in the change of the rolling material variable is determined from the measurement signal, and the rolling parameter is determined on the basis of the determined frequency.

Abstract: An optical position-measuring device includes a measuring standard having a first grating in a form of a periodic incremental graduation and an absolute mark. A scanning unit is displaceable relative to the measuring standard in a measuring direction. The scanning unit has at least one second grating disposed at a scanning distance from the first grating. A first detector array is configured to obtain a first scanning signal for purposes of position determination in which the gratings are illuminated with light of a first wavelength. A second detector array is configured to obtain a second scanning signal for purposes of position determination in which the absolute mark is illuminated with light of a second wavelength. The first wavelength is shorter than the second wavelength.

Abstract: An optical position-measuring device includes a measuring standard having a first grating in a form of a periodic incremental graduation and an absolute mark. A scanning unit is displaceable relative to the measuring standard in a measuring direction. The scanning unit has at least one second grating disposed at a scanning distance from the first grating. A first detector array is configured to obtain a first scanning signal for purposes of position determination in which the gratings are illuminated with light of a first wavelength. A second detector array is configured to obtain a second scanning signal for purposes of position determination in which the absolute mark is illuminated with light of a second wavelength. The first wavelength is shorter than the second wavelength.