Patent ID: 8820969

Claim:
An explosion protection housing comprising: a housing body ( 1 ) with a wall having a through opening therein, a clear, transparent packing ( 10 ) seated in the through opening having opposite ends defined by inner and outer planar faces, said inner planar face ( 13 ) being located in the housing body ( 1 ) and said outer planar face being visible from outside the housing, a converging lens ( 15 ) in front of the inner planar face ( 13 ), a diverging lens ( 16 ) in front of the outer planar face ( 12 ), and a light source ( 18 ) in front of the inner converging lens ( 15 ) for transmitting light to said inner converging lens ( 15 ) and in turn through said packing ( 10 ) and the diverging lens ( 16 ).