Page 337 - High Power Laser Handbook
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306 So l i d - S t at e La s e r s Ultrafast Solid-State Lasers 307
Figure 12.3 Diagram of 1:1 telescope-style pulse stretcher. Shown is a
double-pass system (4f), with lenses for clarity. Mirrors may be used to
avoid chromatic aberrations in the stretcher.
Figure 12.4 Diagram of Treacy-style grating compressor. 19
/
4 ω 2 πL c 2 12
ϕω = c () 1 − − sin γ (12.4)
c ωd
With such a matched stretcher and compressor, the phase delay for all
frequencies is zero.
Because refractive material has a different index of refraction for
different frequencies, however, any transmissive optic or laser gain
material between the stretcher and the compressor imposes phase
distortion, given by
ωω
Ln() 1
ϕω = () m θ = sin −1 sin θ (12.5)
ω
m c cos θ n() i
