Abstract: The invention relates to a spectrometer for material analysis and to a control method for a spectrometer. The spectrometer includes a radiant source (140) formed by multiple single radiation sources (141) having different central wavelengths, for generating a measuring signal, a measurement object (100) containing a material to be analyzed, at least one electrically tunable Fabry-Perot filter (120, 220) for the band pass filtering the measuring signal by at least two pass bands, and a detector (300, 400) for detecting said filtered measuring signals received from the measurement object (100).

Abstract: A manufacturing method for a vacuum measuring cell provides first and second Al2O3 ceramic or sapphire housing bodies on opposite sides of an Al2O3 ceramic or sapphire membrane sealed to the bodies at its opposite peripheral edges. A reference vacuum chamber and a measuring vacuum chamber are on opposite sides of the membrane. An optical transparent window is provided in the first housing body and an optically reflective material is provided on a central region of the membrane. A lens is above the optical transparent window for optically linking to the optically reflective material on the membrane and an optical fiber outside the reference vacuum chamber and at a distance from the optical transparent window feeds light through the lens and window and in and out onto the optically reflective material on the membrane so that the level of membrane deflection is detected by a Fabry-Perot Interferometer.

Abstract: A manufacturing method for a vacuum measuring cell provides first and second Al2O3 ceramic or sapphire housing bodies on opposite sides of an Al2O3 ceramic or sapphire membrane sealed to the bodies at its opposite peripheral edges. A reference vacuum chamber and a measuring vacuum chamber are on opposite sides of the membrane. An optical transparent window is provided in the first housing body and an optically reflective material is provided on a central region of the membrane. A lens is above the optical transparent window for optically linking to the optically reflective material on the membrane and an optical fibre outside the reference vacuum chamber and at a distance from the optical transparent window feeds light through the lens and window and in and out onto the optically reflective material on the membrane so that the level of membrane deflection is detected by a Fabry-Perot Interferometer.

Abstract: A vacuum measuring cell has a first housing body and a membrane, both of Al2O3 ceramic or sapphire. The membrane is planar with a peripheral edge joined by a first seal to the first housing body to form a reference vacuum chamber. A second housing body of Al2O3 ceramic or sapphire opposite the membrane, is joined to the peripheral edge of the membrane by a second seal to form a measurement vacuum chamber. A port connects the vacuum measuring cell to a medium to be measured. At least in the central area of the first housing body, an optical transparent window is formed and at least the central region of the membrane has an optically reflective surface. Outside the reference vacuum chamber, in opposition to and at a distance from the window, an optical fibre is arranged for feeding in and out light onto the surface of the membrane.

Abstract: A capacitive vacuum measuring cell has a first housing body and a membrane, both of Al2O3 ceramic or sapphire. The membrane is planar with a peripheral edge joined by a first seal to the first housing body to form a reference vacuum chamber. A second housing body of Al2O3 ceramic or sapphire opposite the membrane, is joined to the peripheral edge of the membrane by a second seal to form a measurement vacuum chamber. A port connects the vacuum measuring cell to a medium to be measured. At least in the central area of the first housing body, an optical transparent window is formed and at least the central region of the membrane has an optically reflective surface. Outside the reference vacuum chamber, in opposition to and at a distance from the window, an optical fibre is arranged for feeding in and out light onto the surface of the membrane.

Abstract: A method and an arrangement for stopping sectional drive controllably in connection with a fault situation in the supplying mains, the sectional drive comprising a plurality of inverters (4) which are supplied by a DC intermediate circuit (3) supplied by the mains (1), a plurality of electric motors (5) which are controlled by inverters with speed and/or torque control and which are used for implementing speed and tightness reference values of the strip in the sectional drive system, the tightness reference value being predetermined motor-specifically or motor-group-specifically.

Abstract: A method and an arrangement for stopping sectional drive controllably in connection with a fault situation in the supplying mains, the sectional drive comprising a plurality of inverters (4) which are supplied by a DC intermediate circuit (3) supplied by the mains (1), a plurality of electric motors (5) which are controlled by inverters with speed and/or torque control and which are used for implementing speed and tightness reference values of the strip in the sectional drive system, the tightness reference value being predetermined motor-specifically or motor-group-specifically.

Abstract: Measurement equipment based on the measurement of light transmission are plagued by changing characteristics of protective glass surfaces due to contamination or other factors. In a method, light transmission is measured by sending light from a transmitter (1) and recording the received light intensity at a receiver (2), after which the light intensity is obtained by computation means. Light from light sources (5, 6) travels into protective glasses (3, 4) of the transmitter and the receiver so that the light rays are subjected to total internal reflection within the glasses, after which the intensities of the totally reflected light rays are measured by a detector (7, 8), and the obtained intensity values are used for correcting the intensity attenuation, effected by the protective glasses and their contamination onto the path from the transmitter to the receiver.