Laser gwero luso kwakuwala CHIKWANGWANIkumva Gawo Loyamba
Ukadaulo wowonera ulusi wamtundu wamtundu waukadaulo wozindikira womwe umapangidwa limodzi ndiukadaulo waukadaulo wa optical fiber ndi ukadaulo wolumikizirana ulusi, ndipo wakhala imodzi mwanthambi yogwira ntchito kwambiri paukadaulo wazithunzi.Optical fiber sensing system imapangidwa makamaka ndi laser, fiber transmission, sensing element kapena modulation area, kuzindikira kuwala ndi mbali zina.Zigawo zomwe zikufotokozera maonekedwe a kuwala kwa kuwala zikuphatikizapo mphamvu, kutalika kwa mafunde, gawo, polarization state, etc. Izi zikhoza kusinthidwa ndi zochitika zakunja mu kuwala kwa fiber transmission.Mwachitsanzo, pamene kutentha, kupsyinjika, kuthamanga, panopa, kusamuka, kugwedezeka, kuzungulira, kupindika ndi kuchuluka kwa mankhwala zimakhudza njira ya kuwala, magawowa amasintha mofanana.Optical fiber sensing imatengera ubale womwe ulipo pakati pa magawowa ndi zinthu zakunja kuti azindikire kuchuluka kwathupi komwe kumagwirizana.
Pali mitundu yambiri yagwero la laseramagwiritsidwa ntchito m'mawonekedwe a optical fiber sensing, omwe amatha kugawidwa m'magulu awiri: ogwirizanamagwero a laserndi magwero owunikira osagwirizana, osagwirizanamagwero a kuwalamakamaka amaphatikiza kuwala kwa incandescent ndi ma diode otulutsa kuwala, ndipo magwero owunikira amaphatikiza ma laser olimba, ma laser amadzimadzi, ma laser agesi,laser semiconductorndilaser fiber.Zotsatirazi ndizo makamaka zagwero la kuwala kwa laseramagwiritsidwa ntchito kwambiri m'zaka zaposachedwa: mzere wopapatiza wa laser single-frequency laser, single-wavelength kusesa pafupipafupi laser ndi laser yoyera.
1.1 Zofunikira za mzere wopapatizamagwero a kuwala kwa laser
Optical CHIKWANGWANI sensing dongosolo sangathe kupatukana ndi gwero laser, monga kuyeza chizindikiro chonyamulira kuwala yoweyula, laser kuwala gwero lokha ntchito, monga mphamvu bata, laser linewidth, gawo phokoso ndi magawo ena pa kuwala CHIKWANGWANI sensing dongosolo kuzindikira mtunda, kuzindikira. kulondola, kukhudzika ndi mawonekedwe a phokoso amathandizira kwambiri.M'zaka zaposachedwa, ndi chitukuko cha njira zazitali zotalikirapo kwambiri zowonera ulusi wowoneka bwino, akatswiri amaphunziro ndi mafakitale apereka zofunika kwambiri kuti laser miniaturization igwire bwino ntchito, makamaka mu: ukadaulo wa optical frequency domain reflection (OFDR) umagwiritsa ntchito ukadaulo wogwirizana. tekinoloje yowunikira kuti muwunikire ma backrayleigh amwazikana ma fiber owoneka mumtundu wafupipafupi, ndi kuphimba kwakukulu (mamita masauzande).Ubwino wa kusanja kwapamwamba (millimeter-level resolution) ndi kukhudzika kwakukulu (mpaka -100 dBm) zakhala imodzi mwaukadaulo womwe uli ndi chiyembekezo chogwiritsa ntchito kwambiri pakuwunika kwa fiber fiber ndi ukadaulo womvera.Pachimake paukadaulo wa OFDR ndikugwiritsa ntchito gwero loyatsa losavuta kuti mukwaniritse kuwongolera pafupipafupi, kotero magwiridwe antchito a gwero la laser amatsimikizira zinthu zazikulu monga kuzindikirika kwa OFDR, kukhudzika ndi kusamvana.Pamene mtunda wowunikira uli pafupi ndi kutalika kwa mgwirizano, mphamvu ya chizindikiro cha kugunda idzachepetsedwa kwambiri ndi coefficient τ / τc.Kwa gwero la kuwala kwa Gaussian lokhala ndi mawonekedwe owoneka bwino, pofuna kuwonetsetsa kuti kugunda kwafupipafupi kumawonekera kuposa 90%, mgwirizano pakati pa mzere wa mzere wa kuwala kwa gwero la kuwala ndi kutalika kwakutali komwe dongosolo lingathe kukwaniritsa ndi Lmax ~ 0.04vg /f, zomwe zikutanthauza kuti kwa ulusi wokhala ndi kutalika kwa 80 km, m'lifupi mwake mzere wa gwero la kuwala ndi wosakwana 100 Hz.Kuonjezera apo, kupangidwa kwa mapulogalamu ena kumaperekanso zofunikira zapamwamba za mzere wa mzere wa gwero la kuwala.Mwachitsanzo, mu optical fiber hydrophone system, kutalika kwa gwero la kuwala kumatsimikizira phokoso la dongosolo komanso kumatsimikizira chizindikiro chocheperako cha dongosolo.Mu Brillouin optical time domain reflector (BOTDR), kuyeza kwa kutentha ndi kupsinjika kumatsimikiziridwa makamaka ndi kukula kwa mzere wa gwero la kuwala.Mu resonator fiber optic gyro, kutalika kogwirizana kwa mafunde a kuwala kungathe kuwonjezereka mwa kuchepetsa kukula kwa mzere wa gwero la kuwala, potero kumapangitsa kuti kuwala ndi kuya kwa resonance kukhale bwino, kuchepetsa kukula kwa mzere wa resonator, ndikuwonetsetsa muyeso. kulondola kwa fiber optic gyro.
1.2 Zofunikira pakusesa magwero a laser
Single wavelength sweep laser imakhala ndi magwiridwe antchito osinthika a wavelength, imatha kusintha ma lasers angapo okhazikika, kuchepetsa mtengo womanga dongosolo, ndi gawo lofunika kwambiri la makina owonera fiber.Mwachitsanzo, mu trace gas fiber sensing, mitundu yosiyanasiyana ya mpweya imakhala ndi nsonga zamayamwidwe osiyanasiyana.Pofuna kuonetsetsa kuyamwa bwino kwa kuwala pamene mpweya woyezera uli wokwanira ndikukwaniritsa kukhudzika kwapamwamba, m'pofunika kugwirizanitsa kutalika kwa gwero la kuwala kwa mpweya ndi nsonga ya kuyamwa kwa molekyulu ya mpweya.Mtundu wa mpweya womwe ungadziwike umatsimikiziridwa makamaka ndi kutalika kwa gwero la kuwala kozindikira.Chifukwa chake, ma laser opapatiza okhala ndi magwiridwe antchito okhazikika a burodibandi amakhala ndi kusinthasintha kwapamwamba pamakina omvera otere.Mwachitsanzo, m'makina ena omwe amagawidwa optical fiber sensing kutengera kuwunika pafupipafupi kwa domain, laser imayenera kusesedwa mwachangu nthawi ndi nthawi kuti ikwaniritse kuzindikira kolondola kwambiri komanso kutulutsa ma siginecha owoneka bwino, kotero kusinthasintha kwa gwero la laser kumakhala ndi zofunika kwambiri. , ndipo liwiro lakusesa la laser chosinthika nthawi zambiri limafunikira kuti lifike 10pm/μs.Kuphatikiza apo, laser wavelength tunable yopapatiza yopapatiza imatha kugwiritsidwanso ntchito kwambiri mu liDAR, laser sensing yakutali ndi kusanthula kwapamwamba kowonera ndi magawo ena omvera.Kuti mukwaniritse zofunikira za magwiridwe antchito apamwamba a bandwidth, kuwongolera kulondola komanso kuthamanga kwa ma laser ang'ono-wavelength m'munda wa sensing CHIKWANGWANI, cholinga chonse chowerengera ma lasers amtundu wocheperako m'zaka zaposachedwa ndikukwaniritsa kuwongolera mwatsatanetsatane muutali wokulirapo wa wavelength pamaziko otsata makulidwe a laser wopapatiza kwambiri, phokoso lotsika kwambiri, komanso ma frequency ndi mphamvu zotulutsa kopitilira muyeso.
1.3 Kufuna gwero la kuwala kwa laser woyera
Pankhani ya optical sensing, kuwala koyera koyera kwapamwamba kwambiri ndikofunikira kwambiri pakuwongolera magwiridwe antchito.Kufalikira kwa kuwala kwa laser yoyera, kumagwiritsidwa ntchito kwambiri mu optical fiber sensing system.Mwachitsanzo, mukamagwiritsa ntchito fiber Bragg grating (FBG) kuti mupange netiweki ya sensa, kusanthula kowoneka bwino kapena njira yofananira ndi zosefera zitha kugwiritsidwa ntchito potsitsa.Oyamba adagwiritsa ntchito spectrometer kuyesa mwachindunji FBG iliyonse resonant wavelength pamaneti.Yotsirizirayi imagwiritsa ntchito fyuluta yowunikira kuti ifufuze ndikuwongolera FBG mu sensing, zonse zomwe zimafuna gwero la kuwala kwa burodibandi ngati gwero loyesera la FBG.Chifukwa aliyense FBG mwayi maukonde adzakhala ndi kuyikapo imfa, ndipo ali bandiwifi oposa 0,1 nm, ndi demodulation munthawi yomweyo angapo FBG amafuna burodibandi kuwala gwero ndi mkulu mphamvu ndi mkulu bandiwifi.Mwachitsanzo, mukamagwiritsa ntchito nthawi yayitali ya fiber grating (LPFG) kuti mumve, popeza bandwidth ya chiwongola dzanja chimodzi ndi dongosolo la 10 nm, gwero lalikulu la kuwala kokhala ndi bandiwifi yokwanira komanso sipekitiramu yosalala imafunikira kuti iwonetsere kumveka kwake. mawonekedwe apamwamba.Makamaka, ma acoustic fiber grating (AIFG) opangidwa pogwiritsa ntchito ma acousto-optical effect amatha kukwanitsa kusinthasintha kwa kutalika kwa mafunde mpaka 1000 nm pogwiritsa ntchito magetsi.Chifukwa chake, kuyesa kwamphamvu kwa ma grating okhala ndi machunidwe apamwamba kwambiri otere kumabweretsa vuto lalikulu pamtundu wa bandwidth wa gwero lamagetsi ambiri.Momwemonso, m'zaka zaposachedwa, bragg fiber grating yakhala ikugwiritsidwa ntchito kwambiri pantchito yozindikira ulusi.Chifukwa cha mawonekedwe ake amtundu wambiri wotayika, mawonekedwe a kutalika kwa mafunde amatha kufika 40 nm.Kagwiridwe kake kozindikira nthawi zambiri kumakhala kufananiza kusuntha kwachibale pakati pa nsonga zingapo zopatsirana, motero ndikofunikira kuyeza kuchuluka kwake konsekonse.Bandwidth ndi mphamvu ya gwero lalikulu la kuwala kwa sipekitiramu ndizofunikira kuti zikhale zapamwamba.
2. Mkhalidwe wofufuza kunyumba ndi kunja
2.1 Gwero la kuwala kwa laser lalifupi
2.1.1 Semiconductor yopapatiza yogawidwa m'magawo awiri
Mu 2006, Cliche et al.adachepetsa kuchuluka kwa MHz kwa semiconductorDFB laser(kugawidwa kwa laser) ku sikelo ya kHz pogwiritsa ntchito njira yamagetsi;Mu 2011, Kessler et al.ntchito kutentha otsika ndi kukhazikika mkulu umodzi galasi patsekeke pamodzi ndi yogwira mayankho kuwongolera kupeza kopitilira muyeso-yopapatiza linewidth laser linanena bungwe la 40 MHz;Mu 2013, Peng et al adapeza semiconductor laser output ndi linewidth ya 15 kHz pogwiritsa ntchito njira yosinthira maganizo a Fabry-Perot (FP).Njira yamagetsi yamagetsi imagwiritsa ntchito kwambiri pond-Drever-Hall kukhazikika kwafupipafupi kuyankha kuti mzere wa laser wa gwero la kuwala uchepe.Mu 2010, Bernhardi et al.adapanga 1 masentimita a erbium-doped alumina FBG pagawo la silicon oxide kuti apeze kutulutsa kwa laser ndi m'lifupi mwake pafupifupi 1.7 kHz.M'chaka chomwecho, Liang et al.adagwiritsa ntchito mayankho odzibaya okha a Rayleigh wammbuyo womwaza wopangidwa ndi cholumikizira khoma cha Q echo chapamwamba cha semiconductor laser line-width compression, monga momwe tawonetsera pa Chithunzi 1, ndipo pomaliza pake adapeza kutulutsa kwa laser kocheperako kwa 160 Hz.
Chithunzi 1 (a) Chithunzi cha semiconductor laser linewidth compression potengera kudzibaya jekeseni Rayleigh kubalalika kwa kunja kunong'oneza gallery mode resonator;
(b) Mafupipafupi sipekitiramu ya laser yothamanga ya semiconductor yaulere yokhala ndi kutalika kwa 8 MHz;
(c) Mafupipafupi sipekitiramu ya laser yokhala ndi mzere wopindika mpaka 160 Hz
2.1.2 Laser yopapatiza yamtundu wa fiber
Kwa ma linear cavity fiber lasers, kutulutsa kwa laser kocheperako kwamtundu umodzi wautali kumapezedwa ndikufupikitsa kutalika kwa resonator ndikuwonjezera nthawi yayitali.Mu 2004, Spiegelberg et al.adapeza njira imodzi yotalikirapo yopapatiza yotulutsa laser yokhala ndi mizere ya 2 kHz pogwiritsa ntchito njira yachidule ya DBR.Mu 2007, Shen et al.adagwiritsa ntchito 2 cm kwambiri erbium-doped silicon fiber kuti alembe FBG pa Bi-Ge co-doped photosensitive fiber, ndikuyiphatikiza ndi ulusi wogwira ntchito kuti apange chibowo cholumikizana, kupangitsa kuti mzere wake wa laser utuluke m'lifupi kukhala wosakwana 1 kHz.Mu 2010, Yang et al.ntchito 2cm kwambiri doped yochepa liniya patsekeke pamodzi ndi narrowband FBG fyuluta kupeza limodzi longitudinal mode laser linanena bungwe ndi mzere m'lifupi zosakwana 2 kHz.Mu 2014, gululo linagwiritsa ntchito kachipangizo kakang'ono kakang'ono (pafupifupi apangidwe mphete resonator) kuphatikizapo FBG-FP fyuluta kuti apeze laser linanena bungwe ndi yopapatiza mzere m'lifupi, monga momwe chithunzi 3. Mu 2012, Cai et al.adagwiritsa ntchito kabowo kakang'ono ka 1.4cm kuti apeze polarizing laser output ndi mphamvu yotulutsa yoposa 114 mW, wavelength wapakati wa 1540.3 nm, ndi mzere m'lifupi mwake 4.1 kHz.Mu 2013, Meng et al.adagwiritsa ntchito Brillouin kumwazikana kwa erbium-doped fiber yokhala ndi mphete yaying'ono yokhala ndi kachipangizo kosungirako kokwanira kuti apeze njira yotalikirapo imodzi, phokoso lotsika la laser lomwe limatulutsa mphamvu ya 10 mW.Mu 2015, gululi linagwiritsa ntchito mphete yopangidwa ndi 45 cm erbium-doped fiber monga njira yobalalitsira Brillouin kuti ipeze malo otsika komanso kutulutsa kwa laser yopapatiza.
Chithunzi cha 2 (a) Chojambula chojambula cha SLC fiber laser;
(b) Lineshape ya chizindikiro cha heterodyne yoyezedwa ndi kuchedwa kwa fiber 97.6 km
Nthawi yotumiza: Nov-20-2023