I don't have the equipment to carry out this experiment (and maybe it's in the literature somewhere..) however, here goes. Elsewhere on this website I read of an experiment involving setting up the Young's two slit experiment, then replacing the screen with a large thin lens to focus the incident interference pattern onto the same screen pushed further back. But, surprise, the fringes disappear to be replaced on the screen by the image of the two slits. I propose the following. Conduct the same experiment, but this time the thin lens is half silvered, permitting some light to pass through, the rest reflected. Would the reflected light be the interference pattern? I would suggest that it must be. If it were anything else I think the plot would thicken considerably. Would some kind person like to try this out and tell me what was visible?