A visual observation system for monitoring a welding operation being performed in a welding region by a welding torch, the torch having a longitudinal axis and including a housing. The system is composed of a closed light conducting channel supported by the torch and having a first end directed toward the welding region and a second end remote from the first end, and image generating device disposed at the second end of the channel for receiving light entering the channel via the first end in order to generate an image of the scene in front of the first end, a transpatent plate disposed in, and blocking, the light conducting channel for protecting the image generating device against soiling by particles produced by the welding operation, and elements for producing a flow of inert gas past the side of the transparent plate directed toward the first end for opposing the deposition of such particles on the plate. The a light conducting channel is dimensioned such that in at least one direction transverse to the longitudinal axis of the torch, the channel does not project beyond the torch housing.