Hello. I'm interested in the experimental details of the above and have found what I believe to be the original published write up of the experiment. The document is in German and I have managed to get a reasonable understanding of the details mainly from the diagrams and graphs. Translation is proving to be a bit of a task and I hope someone can help me with the following two words related to a Heissenberg lens: Brennebene: The google translation of this word is "burning plane" and I assume this means the focal plane of the lens. If so it seems to make sense. Linsenbrennebene: The google translation of this word is "lens burning plane" and according to my understanding so far this would seem to make sense if the plane was at a distance of 2f in other words twice the focal length from the lens. The problem is that some of the results plotted refer to a distance of f and not 2f, for example the title of the first graph of a particular set is as follows Heisenberg Detector D1 in der Linsenbrennebene, f I would be grateful if anyone can clarify this . Thank you.