Dziwitsanima laser opangidwa ndi ulusi
Ma laser opangidwa ndi ulusi ndizipangizo za laseromwe amagwiritsa ntchito ulusi wophatikizidwa ndi ma ayoni a rare earth (monga ytterbium, erbium, thulium, ndi zina zotero) ngati gain medium. Amakhala ndi gain medium, optical resonant cavity, ndi pump source. Ukadaulo wake wopanga ma pulse umaphatikizapo ukadaulo wa Q-switching (nanosecond level), active mode-locking (picosecond level), passive mode-locking (femtosecond level), ndi ukadaulo waukulu wa oscillation power amplification (MOPA).
Ntchito zamafakitale zimaphatikizapo kudula zitsulo, kuwotcherera, kuyeretsa ndi laser ndi kudula TAB ya lithiamu batire m'munda watsopano wamagetsi, ndi mphamvu yotulutsa yamitundu yambiri yofika pamlingo wa watts zikwi khumi. Mumunda wa lidar, ma laser opangidwa ndi pulsed a 1550nm, omwe ali ndi mphamvu zambiri zogunda komanso mawonekedwe oteteza maso, amagwiritsidwa ntchito m'makina a radar ozungulira komanso oyikidwa m'galimoto.
Mitundu yayikulu yazinthu ndi monga mtundu wa Q-switched, mtundu wa MOPA ndi ulusi wamphamvu kwambiri.ma laser ozunguliraGulu:
1. Laser ya Q-switched fiber: Mfundo ya Q-switching ndi kuwonjezera chipangizo chosinthika mkati mwa laser. Nthawi zambiri, laser imakhala ndi kutayika kwakukulu ndipo pafupifupi palibe kuwala komwe kumatulutsa. Mkati mwa nthawi yochepa kwambiri, kuchepetsa kutayika kwa chipangizocho kumathandiza laser kutulutsa kugunda kwamphamvu kwambiri. Ma laser a Q-switched fiber amatha kuchitika mwachangu kapena mosachitapo kanthu. Ukadaulo wogwira ntchito nthawi zambiri umaphatikizapo kuwonjezera modulator yamphamvu mkati mwa cavity kuti ilamulire kutayika kwa laser. Njira zopanda mphamvu zimagwiritsa ntchito ma saturated absorbers kapena zotsatira zina zosalunjika monga stimulated Raman scattering ndi stimulated Brillouin scattering kuti apange njira za Q-modulation. Ma pulses omwe nthawi zambiri amapangidwa ndi njira za Q-switching ali pamlingo wa nanosecond. Ngati ma pulses afupiafupi apangidwa, amatha kuchitika kudzera mu njira yotseka mode.
2. Laser ya fiber yotsekedwa ndi mode: Imatha kupanga ma pulse afupiafupi kudzera mu njira zogwirira ntchito zotseka mode kapena zotseka mode. Chifukwa cha nthawi yoyankha ya modulator, m'lifupi mwa ma pulse opangidwa ndi active mode-locking nthawi zambiri amakhala pamlingo wa picosecond. Passive mode-locking imagwiritsa ntchito zipangizo zotseka mode zotsekedwa, zomwe zimakhala ndi nthawi yochepa kwambiri yoyankha ndipo zimatha kupanga ma pulse pa sikelo ya femtosecond.
Apa pali chiyambi chachidule cha mfundo yotsekera nkhungu.
Pali mitundu yambirimbiri ya ma longitudinal mu laser resonant cavity. Pa cavity yooneka ngati mphete, nthawi yolumikizira ma longitudinal modes ndi yofanana ndi /CCL, pomwe C ndi liwiro la kuwala ndipo CL ndi kutalika kwa njira yowunikira ya kuwala kwa chizindikiro komwe kumayenda ulendo umodzi wozungulira mkati mwa cavity. Nthawi zambiri, kuchuluka kwa ma gain bandwidth a fiber lasers ndi kwakukulu, ndipo mitundu yambiri ya ma longitudinal modes imagwira ntchito nthawi imodzi. Chiwerengero chonse cha ma longitudinal mode chomwe laser ingathe kulandira chimadalira nthawi ya longitudinal mode ∆ν ndi kuchuluka kwa gain bandwidth ya gain medium. Kaya nthawi ya longitudinal mode ndi yaying'ono, kuchuluka kwa gain bandwidth ya medium ndi kwakukulu, ndipo njira zambiri za longitudinal zimatha kuthandizidwa. Mosiyana ndi zimenezi, kuchepa.
3. Quasi-continuous laser (QCW laser): Ndi njira yapadera yogwirira ntchito pakati pa continuous wave lasers (CW) ndi pulsed lasers. Imapanga mphamvu yotulutsa mwachangu kudzera mu periodic long pulses (duty cycle nthawi zambiri ≤1%) pamene ikusunga mphamvu yochepa ya avareji. Imagwirizanitsa kukhazikika kwa continuous lasers ndi mphamvu yapamwamba kwambiri ya pulsed lasers.
Mfundo yaukadaulo: Ma module a QCW lasers load modulation mu continuouslaserChigawo chodulira ma laser opitilira muyeso kukhala ma pulse sequences amphamvu kwambiri, zomwe zimapangitsa kuti kusinthana pakati pa ma continuous modes ndi pulse mode kukhale kosinthasintha. Mbali yake yaikulu ndi njira ya "short-term burst, long-term cooling". Kuziziritsa mu pulse gap kumachepetsa kusonkhanitsa kutentha ndikuchepetsa chiopsezo cha kusintha kwa kutentha kwa zinthu.
Ubwino ndi mawonekedwe: Kuphatikiza kwa Dual-mode: Kumaphatikiza mphamvu yayikulu ya pulse mode (mpaka nthawi 10 kuposa mphamvu yapakati ya continuous mode) ndi magwiridwe antchito apamwamba komanso kukhazikika kwa continuous mode.
Kugwiritsa ntchito mphamvu zochepa: Kugwiritsa ntchito mphamvu zambiri zamagetsi komanso kugwiritsa ntchito mphamvu zochepa kwa nthawi yayitali.
Ubwino wa mtanda: Ubwino wa mtanda wa lasers wa fiber umathandizira makina olondola ang'onoang'ono.
Nthawi yotumizira: Novembala-10-2025