Security element and process for producing it

The security element has a picture element (22) representing open picture information and another picture element producing hidden picture information. The second picture element includes fine line patterns, which are arranged partially overlapping each other in different depth of image planes of the security element. The line patterns produce recognizable Moire effects only during observation with directed light. The Moire effects are not recognizable during the observation with diffused light. Independent claims are also included for the following: (1) a method of manufacturing a security element (2) a security paper for producing a valuable document (3) a data carrier e.g. valuable document, comprising a security element.