Lasers & Optoelectronics Lecture 9: Gaussian Beam, Cavity Design (Cornell ECE4300 Fall 2016)

Here some numerical examples are first considered to show use of the Gaussian beam equation. Then the cavity design problem is discussed with some examples as well.
Cornell ECE4300 taught in Fall 2016 by Profs. Debdeep Jena and Clif Pollock. (Website: djena.engineering.cornell.edu...)

[@manbeast1586]

Excellent work, thank you

[@yifanwang2645]

Well explained!

[@annankldun4040]

Great lecture. Thank you.

[@brendawilliams8062]

Thankyou

[@AL6kar]

At about 25:00 he draws completely wrong envelope. Yes, minimum happen closer to the lens compared to geometric ray-tracing, but envelope won't get inside that cone/triangle formed by "outer rays" of the beam. In his picture waist would be much bigger.

[@zhiyifeng4455]

Why?

[@brendawilliams8062]

Does this imply that 388 and 3890073002 are involved?

[@brendawilliams8062]

Never mind. If it’s a 3888 thing then 3.16 works.

[@maxd8132]

@0:46 when he writes the electric field, he has a w0/w0 term.. Is it a mistake or am I totally not following ?

[@chevestong]

The full equation is: E(x, y, z) = [w₀/w(z)] * exp[ - (r/w)² ] * exp[ -j (kz - atan(z/z₀)) ] * exp[ -j (k r² / 2R(z)) ]. But, w(z) = w₀ * sqrt[ 1 + (z/z₀)² ], so you get what Dr. Pollock writes out at 0:46.