Doesn't a pinhole demonstrated the duality of light, i.e. that light acts as if it is both a particle and a wave. A lens bends light same as water or any other medium light can travel thru, at the interface. Or is that just diffraction at the pinhole itself helps cause an upside down image with no bending at all. As you can tell I may be a little confused. Been that way since high school when I asked the Physics teacher "What is Light?" and got no satisfactory answer. Then there is that famous 2-slit experiment and Mr Einstein.