Pulse Dav ntawm Pulsed Lasers

Pulse dav hais txog lub sijhawm ntawm lub mem tes, thiab qhov ntau yam feem ntau ncua los ntawm nanoseconds (ns, 10^-9vib nas this) mus femtoseconds (fs, 10^-15vib nas this). Pulsed lasers nrog sib txawv mem tes dav yog tsim rau ntau yam kev siv:

- Luv mem tes dav (Picosecond/Femtosecond):

Zoo tagnrho rau precision machining ntawm cov ntaub ntawv tsis yooj yim (xws li, iav, sapphire) kom txo tau cov kab nrib pleb.

- Ntev Pulse Width (Nanosecond): Tsim nyog rau kev txiav hlau, vuam, thiab lwm yam kev siv uas yuav tsum tau ua kom sov.

- Femtosecond Laser: Siv hauv kev phais qhov muag (xws li LASIK) vim tias nws tuaj yeem ua kom raug txiav nrog kev puas tsuaj tsawg rau cov ntaub so ntswg.

- Ultrashort Pulses: Siv los kawm ultrafast dynamic txheej txheem, xws li molecular vibrations thiab tshuaj tiv thaiv.

Cov mem tes dav cuam tshuam rau kev ua haujlwm ntawm lub laser, xws li lub zog siab (P_ncov= pulse zog/pulse width. Qhov luv luv ntawm pulse dav, lub siab tshaj lub hwj chim rau tib lub zog ib leeg-mem tes.) Nws kuj cuam tshuam cov teebmeem thermal: ntev mem tes dav, zoo li nanoseconds, tuaj yeem ua rau thermal tsub zuj zuj hauv cov ntaub ntawv, ua rau melting lossis thermal puas; luv pulse widths, zoo li picoseconds los yog femtoseconds, pab kom "txias ua" nrog txo tshav kub-cuam tshuam cheeb tsam.

Fiber lasers feem ntau tswj thiab kho pulse dav siv cov txheej txheem hauv qab no:

1. Q-Switching: Tsim cov pulses nanosecond los ntawm kev hloov pauv cov resonator poob los tsim cov pulses siab zog.

2. Hom-Locking: Tsim picosecond lossis femtosecond ultrashort pulses los ntawm synchronizing cov hom longitudinal hauv lub resonator.

3. Modulators lossis Nonlinear Effects: Piv txwv li, siv Nonlinear Polarization Rotation (NPR) hauv fibers los yog saturable absorbers los compress cov mem tes dav.