There is described a printing press (100***; 100****) adapted to carry out printing on a sheet-like or web-like substrate (S), in particular for the production of security documents such as banknotes, comprising a printing unit (2*; 2**; 2***; 2****) designed to print a first side (I) and/or a second side (II) of the substrate (S). The printing press (100***; 100****) further comprises an in-line casting device (80; 80*; 80**; 80***) adapted to apply a layer of material acting as an optical medium on a portion of a first side (I, II) of the substrate (S) and to replicate and form a micro-optical structure (L) in the layer of material acting as optical medium. The printing unit (2*; 2**; 2***; 2****) is furthermore adapted to print at least one printed pattern on the first or second side (I, II) of the substrate (S) in register with the micro-optical structure (L), wherein the printing unit (2*; 2**; 2***; 2****) comprises at least a first printing group (93) being adapted to print at least one printed pattern on the second side (II) of the substrate (S) in register with the micro-optical structure (L) and wherein the in-line casting device (80; 80*; 80**; 80***) comprises at least one embossing cylinder (85), which embossing cylinder (85) also is acting as counter-pressure cylinder and cooperates with a printing cylinder (8) of the at least first printing group (93) and/or whereas the in-line casting device (80; 80*; 80**; 80***) and the at least a first printing group (93) being arranged at the Substrate transport path such way, that in-line casting of the micro-optical structure, on one side of the sheets S, and printing of the associated pattern, on the other side of the sheets S, are performed in a same step, without this involving any sheet transfer operation.