Composite window security device

A security document or device includes an area formed from a transparent plastics material (10), at least one partially opacifying layer (12, 14,16) applied to 5 a first side of the transparent plastics material, at least one partially opacifying layer (22,24) applied to the opposite second side of the transparent plastics material, at least one coloured layer (18, 26) on one or both of said first and second sides of the transparent plastics material (10), and at least one security layer (28) applied on one or both sides of the transparent plastics material. The 10 partially opacifying layers (12, 14, 16, 22, 24) on both sides of the substrate are omitted in at least one area to form a window area (11) in the security document or device. The security layer (28) extends at least partially over the window and into the surrounding region covered by the partially opacifying layers (12, 14, 16, 22, 24). The partially opacifying layers (12, 14, 16, 22, 24), the at least one 15 coloured layer (18, 26), the window area (11) and the at least one security layer (28) cooperate to produce a first image visible in reflection from the first side of the transparent plastics, a second image visible in reflection from the second side of the transparent plastics material, and a third image visible in transmission from both sides of the transparent plastics material. NJ -P hi m h-.) .. ...c; :1. 11...