Abstract: A security device, which is suitable in particular for improving the anti-forgery security of payment means, wherein the security device comprises a flat light reflection element. Several three-dimensional diffractive surface elements are arranged on a surface of the light reflection element. The surface elements comprise a diffraction grating on a light outlet surface. The diffraction gratings of a group of light surface elements are designed and/or arranged in such a way that an asterism is produced for an observer and/or an examination device.

Abstract: The present invention relates to a method of forming a nanopattern, and, more particularly, to a method of continuously forming a nanopattern in a large area and a method of forming a nanopattern on a substrate having a roll shape, and a substrate having a pattern formed using the method. A method of relatively moving a specimen having a large area and a light source of interfering light and a method of performing exposure through the relative axial movement of the light source of interfering light and the substrate having a roll shape while the substrate having a roll shape rotates are used to avoid the problems occurring in the related art, such as a large space required for the equipment during the formation of nanopatterns, a limited output of a laser, and a limited degree of freedom in patterns.