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

[@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.

[@Porizcone]

look into the last presentation, where he concludes with this überequation

[@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.

[@yifanwang2645]

Well explained!

[@annankldun4040]

Great lecture. Thank you.

[@brendawilliams8062]

Thankyou

[@manbeast1586]

Excellent work, thank you