Lens Aperture Function Explained

/ edmundsj
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In this video I go over the lens aperture function (also known as a phase mask). Lenses essentially apply a quadratic phase to the wavefront, which allows for cancellation of the quadratic phase due to free-space propagation. This is what enables lenses to perform Fourier Transforms.
This is part of my graduate series on optoelectronics / photonics, and is based primarily on Coldren's book on Lasers as well as graduate-level coursework I have taken in the EECS department at UC Berkeley.
Hope you found this video helpful, please post in the comments below anything I can do to improve future videos, or suggestions you have for future videos.

[@luketesla7343]

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[@chicougouilla]

I think there might be a sign mistake, as shown in the thin transparency video it should be e^(+j(n-1)kl) if your propagating wave is e^(-jkz). As the lens will delay the phase it should have the opposite sign of a propagating wave inside the exponential

[@veruthev3702]

YOU ARE GOD