Tekinoroji yeLaser source yefaibha yemazisokunzwa Chikamu Chekutanga
Tekinoroji yekuona fiber ye optical imhando yetekinoroji yekuona yakagadzirwa pamwe chete netekinoroji ye optical fiber uye tekinoroji yekutaurirana ye optical fiber, uye yave imwe yematavi anoshanda zvakanyanya etekinoroji ye photoelectric. Sisitimu yekuona fiber ye optical inonyanya kuumbwa ne laser, transmission fiber, sensing element kana modulation area, light detection nezvimwe zvikamu. Ma parameter anotsanangura hunhu hwe light wave anosanganisira intensity, wavelength, phase, polarization state, nezvimwewo. Ma parameter aya anogona kuchinjwa ne external influences mu optical fiber transmission. Semuenzaniso, kana tembiricha, strain, pressure, current, displacement, vibration, rotation, bend uye chemical quantity zvichikanganisa nzira ye optical, ma parameter aya anochinja zvinoenderana. Optical fiber sensing yakavakirwa pahukama huripo pakati pema parameter aya nezvinhu zvekunze kuti ione huwandu hwe physical hunoenderana.
Kune mhando dzakawanda dzesosi yelaserinoshandiswa mumasisitimu ekuona fiber e optical, ayo anogona kukamurwa kuita mapoka maviri: akabatanamasosi elaseruye manyuko echiedza asina kurongeka, asina kurongekamanyuko echiedzaZvinonyanya kusanganisira chiedza cheincandescent uye madiode anoburitsa chiedza, uye masosi echiedza akabatana anosanganisira ma laser akasimba, ma laser emvura, ma laser egasi,laser ye semiconductoruyelaser yefaibhaZvinotevera ndezvechiedza chelaseryakashandiswa zvakanyanya mumunda wekuona fiber mumakore achangopfuura: single-frequency laser yakamanikana, single-wavelength sweep frequency laser uye white laser.
1.1 Zvinodiwa pakupamhama kwemutsara wakamanikanamanyuko echiedza chelaser
Sisitimu yekuona fiber ye optical haigone kuparadzaniswa ne laser source, sezvo mafungu emwenje anoyerwa, laser light source pachayo, akadai sekugadzikana kwesimba, laser linewidth, phase noise nezvimwe zvinongedzo pa optical fiber sensing system detection distance, detection accuracy, sensitivity uye ruzha zvine basa guru. Mumakore achangopfuura, nekuvandudzwa kwemasisitimu ekuona fiber ye optical fiber e distance-high resolution, academia nemaindasitiri vakaisa zvinodiwa zvakanyanya zve linewidth performance ye laser miniaturization, kunyanya mu: tekinoroji ye optical frequency domain reflection (OFDR) inoshandisa coherent detection technology kuongorora backrayleigh scattered signals ye optical fibers munzvimbo ye frequency, ine wide coverage (zviuru zvemamita). Zvakanakira high resolution (millimeter-level resolution) uye high sensitivity (kusvika -100 dBm) zvave imwe yetekinoroji ine mikana yakawanda yekushandisa mu distributed optical fiber measurement uye sensitivity technology. Chinhu chikuru che OFDR technology ndechekushandisa tunoble light source kuti uwane optical frequency tuning, saka performance ye laser source ndiyo inosarudza zvinhu zvakakosha zvakaita se OFDR detection range, sensitivity uye resolution. Kana daro re reflection point riri pedyo nehurefu hwekubatana, simba re beat signal richadzikiswa zvakanyanya ne coefficient τ/τc. Kune Gaussian light source ine chimiro che spectral, kuitira kuti frequency ye beat ive ne visibility inopfuura 90%, hukama huripo pakati pe line width ye light source nehurefu hwe sensing iyo system inogona kuwana i Lmax~0.04vg/f, zvinoreva kuti kune fiber ine hurefu hwe 80 km, line width ye light source iri pasi pe 100 Hz. Pamusoro pezvo, kuvandudzwa kwemamwe maapplication kunoisawo zvinodiwa zvepamusoro zve linewidth ye light source. Semuenzaniso, mu optical fiber hydrophone system, linewidth ye light source inosarudza ruzha rwe system uye inosarudzawo minimum meacual signal ye system. MuBrillouin optical time domain reflector (BOTDR), measurement ye measurement ye tembiricha uye stress inonyanya kutsanangurwa ne linewidth ye light source. Mu resonator fiber optic gyro, kureba kwekubatana kwemafungu echiedza kunogona kuwedzerwa nekuderedza upamhi hwemutsara wechiedza, nokudaro zvichivandudza kusimba uye kudzika kwe resonator, kuderedza upamhi hwemutsara we resonator, uye kuve nechokwadi chekuti fiber optic gyro inoyerwa zvakanaka.
1.2 Zvinodiwa pakushandisa laser yekutsvaira
Laser imwe chete inotsvaira wavelength ine mashandiro ekuchinjika kwewavelength, inogona kutsiva ma laser akawanda akagadziriswa ewavelength, inoderedza mutengo wekuvaka sisitimu, chikamu chakakosha chesystem yekunzwa fiber ye optical. Semuenzaniso, mukunzwa fiber ye trace gas, mhando dzakasiyana dzemagasi dzine peaks dzakasiyana dzekunyudzwa kwegasi. Kuti uve nechokwadi chekuti chiedza chinonyudzwa zvakanaka kana gasi rekuyera rakakwana uye kuwana kunzwisisika kwepamusoro kwekuyera, zvakakosha kuenderana wavelength yesimba rekutumira chiedza nechikamu chekunyudzwa chemorekuru yegasi. Rudzi rwegasi runogona kuonekwa runonyanya kutsanangurwa nehurefu hwewavelength yesimba rekuona chiedza. Naizvozvo, ma laser akamanikana ane mashandiro ekuchinjika kwebroadband ane kuchinjika kwakanyanya kwekuyera mumasisitimu akadaro ekunzwa. Semuenzaniso, mune mamwe masisitimu ekunzwa fiber akagoverwa zvichibva pakutarisa kwe optical frequency domain, laser inoda kukurumidza kutsvairwa nguva nenguva kuti iwane kuona kwakanyatsojeka uye kuderedzwa kwezviratidzo zve optical, saka mwero we modulation wesimba re laser une zvinodiwa zvakakwirira, uye kumhanya kwekutsvaira kwe laser inogadziriswa kunowanzo dikanwa kusvika 10 pm/μs. Pamusoro pezvo, laser ine width yakamanikana inogona kushandiswawo zvakanyanya mu liDAR, laser remote sensing uye high-resolution spectral analysis nedzimwe nzvimbo dzekunzwa. Kuti zvizadzise zvinodiwa zve high performance parameters ye tuning bandwidth, tuning accuracy uye tuning speed ye single-wavelength lasers mumunda we fiber sensing, chinangwa chikuru chekudzidza tunable narrow-width fiber lasers mumakore achangopfuura ndechekuwana high-precision tuning munzvimbo yakakura ye wavelength zvichibva pakutevera ultra-narrow laser linewidth, ultra-low phase noise, uye ultra-stable output frequency nesimba.
1.3 Kudiwa kwechiedza cheraser chena
Munyaya yekuona optical, laser yechiedza chemhando yepamusoro yakakosha zvikuru pakuvandudza mashandiro esystem. Kana spectrum yelaser yechiedza chechena yakafara, ndipo painonyanya kushandiswa mu optical fiber sensing system. Semuenzaniso, pakushandisa fiber Bragg grating (FBG) kugadzira sensor network, spectral analysis kana tunable filter matching method inogona kushandiswa pa demodulation. Yekutanga yakashandisa spectrometer kuyedza zvakananga FBG resonant wavelength yega yega mu network. Yekupedzisira inoshandisa reference filter kuteedzera nekutarisa FBG mu sensing, zvese zvinoda broadband light source se test light source yeFBG. Nekuti yega yega FBG access network ichave nekurasikirwa kwakati, uye ine bandwidth inopfuura 0.1 nm, demodulation ye multiple FBG panguva imwe chete inoda broadband light source ine simba rakawanda uye bandwidth yakakwira. Semuenzaniso, kana uchishandisa fiber grating yenguva refu (LPFG) pakuona, sezvo bandwidth ye peak imwe chete yekurasikirwa iri muhurongwa hwe 10 nm, broad spectrum light source ine bandwidth yakakwana uye relative flat spectrum inodiwa kuti inyatso ratidza hunhu hwayo hwe resonant peak. Kunyanya, acoustic fiber grating (AIFG) yakagadzirwa nekushandisa acousto-optical effect inogona kuwana tuning range ye resonant wavelength inosvika 1000 nm kuburikidza ne electrical tuning. Saka, dynamic grating testing ine ultra-wide tuning range yakadaro inokonzera dambudziko guru kune bandwidth range ye wide-spectrum light source. Saizvozvowo, mumakore achangopfuura, tilted Bragg fiber grating yakashandiswawo zvakanyanya mumunda we fiber sensing. Nekuda kwehunhu hwayo hwe multi-peak loss spectrum, wavelength distribution range inogona kusvika 40 nm. Maitiro ayo ekuona anowanzo enzanisa kufamba pakati pema peaks akawanda ekutumira, saka zvakakosha kuyera transmission spectrum yayo zvizere. Bandwidth nesimba re wide spectrum light source zvinofanirwa kunge zvakakwirira.
2. Chinzvimbo chekutsvagisa kumba nekune dzimwe nyika
2.1 Chitubu chechiedza chelaser chakamanikana
2.1.1 Laser yemhinduro yakakamanikana ine upamhi hwe semiconductor yakagoverwa
Muna 2006, Cliche nevamwe vake vakaderedza chiyero cheMHz chesemiconductorLaser yeDFB(distributed feedback laser) kusvika ku kHz scale vachishandisa nzira ye electrical feedback; Muna 2011, Kessler nevamwe vake vakashandisa low temperature uye high stability single crystal cavity pamwe chete ne active feedback control kuti vawane ultra-narrow linewidth laser output ye 40 MHz; Muna 2013, Peng nevamwe vake vakawana semiconductor laser output ine linewidth ye 15 kHz vachishandisa nzira ye external Fabry-Perot (FP) feedback adjustment. Nzira ye electrical feedback yakashandisa zvakanyanya Pond-Drever-Hall frequency stabilization feedback kuti laser linewidth ye light source ideredzwe. Muna 2010, Bernhardi nevamwe vake vakagadzira 1 cm ye erbium-doped alumina FBG pane silicon oxide substrate kuti vawane laser output ine line width ye 1.7 kHz. Mugore rimwe chete, Liang nevamwe vake. yakashandisa mhinduro yekuzvibaya yega yeRayleigh scattering yekumashure yakagadzirwa nehigh-Q echo wall resonator yekumanikidza semiconductor laser line-width compression, sezvakaratidzwa muMufananidzo 1, uye pakupedzisira yakawana kuburitswa kwelaser yakamanikana ye160 Hz.
Mufananidzo 1 (a) Dhizaini yekumanikidzwa kwe semiconductor laser linewidth zvichibva pakuzvibaya Rayleigh scattering ye external whispering gallery mode resonator;
(b) Frequency spectrum ye free running semiconductor laser ine linewidth ye8 MHz;
(c) Frequency spectrum yelaser ine linewidth yakamanikidzwa kusvika 160 Hz
2.1.2 Laser yefiber yakamanikana ine upamhi hwakatetepa
Kune linear cavity fiber lasers, narrow linewidth laser output ye single longitudinal mode inowanikwa nekupfupisa urefu hwe resonator uye kuwedzera longitudinal mode interval. Muna 2004, Spiegelberg nevamwe vakawana single longitudinal mode narrow linewidth laser output ine linewidth ye2 kHz vachishandisa DBR short cavity method. Muna 2007, Shen nevamwe vakashandisa 2 cm heavyweight erbium-doped silicon fiber kunyora FBG paBi-Ge co-doped photosensitive fiber, uye vakaisanganisa ne active fiber kugadzira compact linear cavity, zvichiita kuti laser output line width yayo ive pasi pe1 kHz. Muna 2010, Yang nevamwe vakashandisa 2 cm highly doped short linear cavity yakabatana ne narrowband FBG filter kuti vawane single longitudinal mode laser output ine line width ye less than 2 kHz. Muna 2014, timu yakashandisa kaburi kapfupi kemutsetse (virtual folded ring resonator) pamwe chete neFBG-FP filter kuti iwane laser output ine mutsetse wakamanikana, sezvakaratidzwa muMufananidzo 3. Muna 2012, Cai nevamwe vakashandisa chimiro chekaburi kapfupi che 1.4cm kuti vawane polarizing laser output ine simba rekubuda rinodarika 114 mW, central wavelength ye 1540.3 nm, uye mutsetse wakafara we 4.1 kHz. Muna 2013, Meng nevamwe vakashandisa Brillouin scattering ye erbium-doped fiber ine short ring cavity ye full-bias preserving device kuti vawane single-longitudinal mode, low-phase noise laser output ine output power ye 10 mW. Muna 2015, timu yakashandisa ring cavity ine 45 cm erbium-doped fiber seBrillouin scattering gain medium kuti iwane low threshold uye narrow linewidth laser output.
Mufananidzo 2 (a) Mufananidzo weSLC fiber laser;
(b) Chimiro chemutsetse wechiratidzo cheheterodyne chakayerwa nekunonoka kwefiber kwe97.6 km
Nguva yekutumira: Mbudzi-20-2023