Abstract: The present invention is concerned with a support (1), in particular an optical disc, with a surface structure for the detection of at least one optically-active substance within the evanescent-field (5) at one surface of the support (1), whereby the surface structure allows the generation of an evanescent-field (5) in a medium (2) adjacent to the surface structure. The surface structure comprises one or more sections of the surface of the support (1), which are inclined (?wedge) with respect to the general orientation of the surface of the support (1). The invention also concerns a device employing such a support (1) with a surface structure, in particular an optical disc and uses of the support (1) with a surface structure and the device.

Abstract: Method and device for positioning a component (3) with respect to a frame (2), whereby at least on positioning element (12) is introduced through at least one opening (8) of the frame. One end of the positioning element is inserted into a groove (13) of the component lying on the frame, whereby the end of the positioning element is pressed against at least one wall forming a boundary of the groove for positioning the component into the desired position.