For reducing the NOx-emission of a large sized two stroke diesel engine having at least one combustion room, a reciprocating piston and an exhaust opening controlled by an exhaust valve at each work cyclus a small volume of burnt gas is retained in the combustion room and so added to the fresh air for the next combustion. The lighting device applies a liquid crystal display panel as a luminaire, the liquid crystal display panel has a first polarizer only on a light input side. 3 times the resistance value taken from the database. When the radio wave-faulted area is a temporary radio wave-faulted area, the predetermined reconnection time is extended.