There’s not a great deal on the web that deals with optics in great
detail. There are however lots of great books.
Goodman’s Introduction to Fourier Optics
This is the bible as far as Fourier Optics goes.
A good general overview of optics. It’s very well written and easy to
understand. A classic undergraduate text that I would recommend to anyone
Born and Wolf’s Principles of Optics
In a word – rigorous. If you want a mathematically rigorous description of
light here is a good place. The only book I own that derives Zernike
polynomials. I would recommend this for people who have exhausted Hecht.
The granddaddy of optics. Some what dated, it was first published in 1704
and is still in print. I wouldn’t really try and learn about optics from this
book, some of it is wrong, still it’s an interesting read.