The present invention relates to a security element composed of at least one light-transmitting substrate on which a substantially opaque, screened layer composed of grid elements is located. According to the present invention, within the substantially opaque, screened layer composed of grid elements, at least one thin, solid, substantially opaque line is arranged that exhibits the form of at least one alphanumeric character, a graphic or a pattern. Such lines have line widths of at least 0.1 mm to 5 mm, preferably of 0.2 mm to 0.7 mm, particularly preferably of about 0.5 mm. Instead of lines, also extensive regions without any gap may be used, such that the alphanumeric character, pattern or graphic formed is perceptible only in transmitted light, but not in reflected light. The security element thus displays, at least when viewed from the side of the substantially opaque, screened layer, in top view, a different appearance than when looked through.