Thought this might be of interest...
So I was talking to my RT specialist after my session and was asking about the various bits of the machine.
She pointed out the main energy source and mentioned the green light coming from it.
I said "laser?". She said "a bit more" and held a black card about the size of a pack of cards up under it and showed a big patch of green light.
She explained this was the template beam that shows the range of the beam.
It looked sort of like the cross section of a wine glass mixed with the output from an oscilloscope at a glance. I would have tried to understand more but the lead supervisor kicked me out for gossiping and holding the queue up :)
I can see how in 3D it would track around the bladder and urethra to cover a specific area based on the shape but I was really surprised at how large the field was. I was expecting like a 50p size but this was much larger. Looks like I am getting a good old roasting inside!
They are doing an open day soon so will see the innards and ask more then.
I am very lucky because the RT team on the room I am in are a brilliant bunch, friendly, caring and willing to put up with a grumpy old fart like me!
P