A collimated plane wave U(r) = A exp(jkz) is incident on a thin negative (diverging) lens as shown below. f f f (a) (5 points) What is the expression for the complex transmittance of the thin lens? (b) (5 points) What is the expression for the output wave just after the lens? (c) (5 points) To an observer after the lens, where does it appear the wave is emanating from? (d) (5 points) Sketch the wavefronts after the lens - try to draw them to scale given the apparent source of the wave