Double glazing; triple reflection

 

I noticed that the halogen bulbs produced a triple reflection in the double glazing. The nearest reflection must come from the front glass and the second bright reflection will be from the outer layer of glass. But I noticed a third, dimmer reflection. This must be when some of the light coming back from the outer pane reflects back out off the outer side of the inner pane. It is then reflected back our way again. I wonder if by drawing it is possible to figure out how the path differences result in the different angles.