Abstract: The invention relates to a device and a method for the measurement of the curvature of a surface (1), which is more exact and less expensive than prior art devices. The device comprises a light source (2) for the irradiation of a light beam (3) onto the surface (1), in which a birefingent element (4) is arranged between light source (2) and surface (1), in which furthermore a detector (5) is arranged for the detection of the partial beams (6,7), that are reflected from the surface (1), and at least one main axis (17) of the birefringent element (4) is positioned with respect to the light beam (3) of the light source (2) in such a way, that the light beam (3) of the light source (2) is split up into at least two parallel beams (6,7).

Abstract: The invention relates to a device and a method for the measurement of the curvature of a surface (1). It is the object of the present invention to provide a device for the determination of the curvature of a surface (1), that is more exact and less expensive as the devices of the prior art. Therefore the device comprises a light source (2) for the irradiation of a light beam (3) onto the surface (1), in which a birefingent element (4) is arranged between light source (2) and surface (1), in which furthermore a detector (5) is arranged for the detection of the partial beams (6,7), that are reflected at the surface (1), and at least one main axis (17) of the birefringent element (4) is positioned with respect to the light beam (3) of the light source (2) in such a way, that the light beam (3) of the light source (2) is split up into at least two parallel beams (6,7), if necessary with the help of additional optical elements.