The panes (1) of a naval vessel or military vehicle are often coated with a radar-reflecting layer (20) for reduction of the radar signature of the vessel/vehicle. At the same time this layer increases an enemy's possibility of recognizing the vessel in passive IR reconnaissance since the layer increases the reflectance also for IR radiation to a considerable extent. As a result, the intensity of IR radiation that an enemy receives from the panes is much lower than that from the rest of the vessel, which with signal processing can be used to increase the possibility of recognizing the vessel. According to the invention, it is suggested that the panes (1) on the outer face (8) also have a second layer (21, 22) to increase emittance especially within the IR range 2-20 .mu.m which is normally used for reconnaissance and the like. This second layer (21, 22) comprises especially two coatings, one of which is active in the IR range 3-5 .mu.m and the second in the IR range 7-14 .mu.m. The first coating (21) is suggested to comprise tin dioxide and the second coating (22) oxidized silicon nitride.