Abstract: The present invention relates to a rotating-compensator ellipsometer, comprising the following elements in the light path in this order according to the propagation direction of light: a light source (1); a polarizer (2); a compensator (3a), arranged in a supporting and rotating assembly (4) and comprising an optical axis (O); an analyzer (5); a detector (6), wherein the rotating-compensator ellipsometer further comprises a control unit (7) that is operably connected to at least one of the above elements, wherein the compensator (3a) is a concave prism, having at least five planar surfaces that are perpendicular to a median plane of the prism, said median plane including the optical axis (O), wherein a first planar surface (301) of the prism is perpendicular to the optical axis (O); a second planar surface (302) of the prism forms an angle of 90°-? with the optical axis (O); a third planar surface (303) of the prism is parallel with the optical axis (O), is perpendicular to the first planar surface (301) and

Abstract: An electric incandescent lamp comprising at least one incandescent filament is provided. The incandescent filament is arranged inside a translucent envelope. The lamp also comprises support wires that protrude out of a stem. The filament has end portions, and each end portion is fixed to a corresponding support wire at a junction point. At least one of the support wires comprises at least one narrowed portion for reducing vibration. The narrowed portions are disposed between the junction point and the stem. In an exemplary embodiment of another aspect of this invention, at least one of the support wires has a second section overhanging beyond the junction point of the end portion of the filament. The at least one narrowed portion for reducing vibration is comprised by the second section. A method for reducing vibration is also disclosed. This method comprises a step of forming at least one narrowed portion in at least one of the support wires.