Teknụzụ maka isi iyi lasereriri anyaịchọpụta Nkebi nke Mbụ
Teknụzụ sensọ eriri anya bụ ụdị teknụzụ mmetụta nke emepụtara yana teknụzụ eriri anya na teknụzụ nkwukọrịta eriri anya, ọ ghọwokwa otu n'ime ngalaba kachasị arụ ọrụ nke teknụzụ fotoelectric. Sistemụ mmetụta eriri anya bụ nke mejupụtara laser, eriri nnyefe, ihe mmetụta ma ọ bụ mpaghara mgbanwe, nchọpụta ìhè na akụkụ ndị ọzọ. Paramita ndị na-akọwa njirimara nke ebili mmiri ọkụ gụnyere ike, ogologo ebili, usoro, ọnọdụ polarization, wdg. Enwere ike ịgbanwe paramita ndị a site na mmetụta mpụga na nnyefe eriri anya. Dịka ọmụmaatụ, mgbe okpomọkụ, nrụgide, nrụgide, ugbu a, mbugharị, mkpọtụ, ntụgharị, mgbagọ na ọnụọgụ kemịkalụ metụtara ụzọ anya, paramita ndị a na-agbanwe n'otu aka ahụ. Nchọpụta eriri anya dabere na mmekọrịta dị n'etiti paramita ndị a na ihe ndị dị n'èzí iji chọpụta ọnụọgụ anụ ahụ kwekọrọ.
E nwere ọtụtụ ụdịisi iyi lasereji ya na sistemụ sensọ eriri anya, nke enwere ike kewaa n'ime ụdị abụọ: coherentisi mmalite laserna isi iyi ọkụ na-adịghị agbanwe agbanwe, enweghị njikọisi mmalite ọkụọkachasị gụnyere ọkụ incandescent na diode ndị na-ewepụta ìhè, ebe isi mmalite ìhè ndị a gụnyere laser siri ike, laser mmiri mmiri, laser gas,laser semiconductornaeriri laserIhe ndị a bụ makaisi iyi ọkụ laserA na-ejikarị ya eme ihe n'ọtụtụ ebe n'ihe gbasara nchọpụta eriri n'afọ ndị na-adịbeghị anya: obosara ahịrị dị warara nke laser otu ugboro, laser otu ugboro ebili mmiri na laser ọcha.
1.1 Ihe achọrọ maka obosara ahịrị dị wararaisi mmalite ọkụ laser
Enweghị ike ikewapụ sistemụ sensọ eriri anya site na isi iyi laser, ebe ọ bụ na a tụrụ aro ebili mmiri ọkụ nke na-ebu ihe mgbaàmà, arụmọrụ isi iyi ọkụ laser n'onwe ya, dị ka nkwụsi ike ike, obosara ahịrị laser, mkpọtụ nkebi na paramita ndị ọzọ na anya nchọpụta sistemụ sensọ eriri anya, izi ezi nchọpụta, mmetụta na njirimara mkpọtụ na-arụ ọrụ dị mkpa. N'afọ ndị na-adịbeghị anya, site na mmepe nke sistemụ sensọ eriri anya dị elu nke dị ogologo, agụmakwụkwọ na ụlọ ọrụ etinyela ihe ndị siri ike karị maka arụmọrụ linewidth nke obere laser, ọkachasị na: teknụzụ ntụgharị mpaghara ugboro ugboro optical frequency (OFDR) na-eji teknụzụ nchọpụta coherent iji nyochaa akara azụrayleigh gbasaara nke eriri anya na mpaghara ugboro, yana mkpuchi sara mbara (puku kwuru puku mita). Uru nke mkpebi dị elu (mkpebi ọkwa milimita) na nnukwu mmetụta (ruo -100 dBm) aghọwo otu n'ime teknụzụ nwere atụmanya ngwa sara mbara na teknụzụ nha eriri anya kesara na mmetụta. Isi ihe dị na teknụzụ OFDR bụ iji isi iyi ọkụ a na-agbanwe agbanwe iji nweta nhazi ugboro anya, yabụ arụmọrụ nke isi iyi laser na-ekpebi ihe ndị bụ isi dị ka oke nchọpụta OFDR, mmetụta na mkpebi. Mgbe anya ebe ntụgharị uche dị nso na ogologo njikọ, a ga-ebelata ike nke akara mkpọtụ site na ihe nhazi τ/τc. Maka isi iyi ọkụ Gaussian nwere ọdịdị spectral, iji hụ na ugboro mkpọtụ ahụ nwere ihe karịrị 90% visibiliti, mmekọrịta dị n'etiti obosara ahịrị nke isi iyi ọkụ na ogologo mmetụta kachasị nke sistemụ ahụ nwere ike iru bụ Lmax~0.04vg/f, nke pụtara na maka eriri nwere ogologo kilomita 80, obosara ahịrị nke isi iyi ọkụ ahụ erughị 100 Hz. Na mgbakwunye, mmepe nke ngwa ndị ọzọ na-etinyekwa ihe achọrọ dị elu maka obosara ahịrị nke isi iyi ọkụ. Dịka ọmụmaatụ, na sistemụ hydrophone eriri optical, obosara ahịrị nke isi iyi ọkụ na-ekpebi mkpọtụ sistemụ ma na-ekpebikwa obere akara a na-atụ anya nke sistemụ ahụ. Na Brillouin optical time domain reflector (BOTDR), mkpebi nha nke okpomọkụ na nrụgide na-adabere na obosara ahịrị nke isi iyi ọkụ. N'ime gyro eriri optic resonator, enwere ike ịbawanye ogologo njikọ nke ebili mmiri ọkụ site na ibelata obosara ahịrị nke isi iyi ọkụ, si otú a na-eme ka ịdị mma na omimi resonator nke resonator ka mma, na-ebelata obosara ahịrị nke resonator, ma na-ahụ na nha nha nke gyro optic fiber ziri ezi.
1.2 Ihe achọrọ maka isi mmalite laser sweep
Laser sweep nke otu ebili mmiri nwere arụmọrụ mgbanwe ebili mmiri, nwere ike dochie ọtụtụ lasers ebili mmiri a kapịrị ọnụ, belata ọnụ ahịa owuwu sistemụ, bụ akụkụ dị mkpa nke sistemụ sensọ eriri anya. Dịka ọmụmaatụ, na nchọpụta eriri gas trace, ụdị gas dị iche iche nwere oke mmịpụta gas dị iche iche. Iji hụ na arụmọrụ mmịpụta ìhè mgbe gas nha zuru oke ma nweta mmetụta nha dị elu, ọ dị mkpa ịhazi ebili mmiri nke isi iyi ọkụ nnyefe na oke mmịpụta gas. Ụdị gas enwere ike ịchọpụta bụ nke a na-ekpebi site na ebili mmiri nke isi iyi ọkụ mmetụta. Ya mere, lasers obosara ahịrị dị warara nwere arụmọrụ nhazi broadband kwụsiri ike nwere mgbanwe nha dị elu na sistemụ mmetụta dị otú ahụ. Dịka ọmụmaatụ, na ụfọdụ sistemụ mmetụta eriri anya nke kesara dabere na ntụgharị mpaghara ugboro anya, ọ dị mkpa ka a na-ehichapụ laser ahụ ngwa ngwa mgbe niile iji nweta nchọpụta doro anya na mwepụ nke akara anya, yabụ ọnụego mgbanwe nke isi iyi laser nwere ihe achọrọ dị elu, a na-achọkarịkwa ọsọ mmịpụta nke laser a na-agbanwe agbanwe iji ruo 10 pm/μs. Tinyere nke ahụ, enwere ike iji laser dị warara nke nwere ike ịgbanwe ogologo ebili na liDAR, nchọpụta anya laser na nyocha spectral dị elu na mpaghara nchọpụta ndị ọzọ. Iji mezuo ihe achọrọ maka paramita arụmọrụ dị elu nke ịgbanwe bandwit, izi ezi nhazi na ọsọ nhazi nke laser otu-wavelength na ngalaba nchọpụta eriri, ebumnuche zuru oke nke ịmụ laser eriri dị warara nke a na-agbanwe agbanwe n'afọ ndị na-adịbeghị anya bụ iji nweta nhazi ziri ezi na oke ebili mmiri buru ibu dabere na ịchụso obosara laser dị warara, mkpọtụ phase dị ala, na ugboro mmepụta siri ike na ike.
1.3 Ọchịchọ maka isi iyi ọkụ laser ọcha
N'ihe gbasara mmetụta anya, laser ọkụ ọcha dị elu dị oke mkpa iji melite arụmọrụ nke sistemụ ahụ. Ka mkpuchi spectrum nke laser ọkụ ọcha buru ibu, otú ahụ ka ojiji ya na sistemụ sensọ eriri optical dịkwuo ukwuu. Dịka ọmụmaatụ, mgbe ị na-eji eriri Bragg grating (FBG) iji wuo netwọk sensọ, enwere ike iji nyocha spectral ma ọ bụ usoro nhazi nzacha a na-agbanwe agbanwe maka demodulation. Nke mbụ jiri spectrometer nwalee ogologo ebili mmiri FBG ọ bụla na netwọk ahụ. Nke ikpeazụ na-eji nzacha ntụaka iji soro ma hazie FBG na mmetụta ahụ, ha abụọ chọrọ isi iyi ọkụ broadband dị ka isi iyi ọkụ nnwale maka FBG. N'ihi na netwọk nnweta FBG ọ bụla ga-enwe mfu ntinye ụfọdụ, ma nwee bandwit nke karịrị 0.1 nm, demodulation n'otu oge nke ọtụtụ FBG chọrọ isi iyi ọkụ broadband nwere ike dị elu na bandwit dị elu. Dịka ọmụmaatụ, mgbe ị na-eji grating eriri ogologo oge (LPFG) maka nchọpụta, ebe ọ bụ na bandwit nke elu mfu otu dị n'usoro nke 10 nm, ọ dị mkpa ka e nwee isi iyi ọkụ spectrum sara mbara nke nwere bandwit zuru oke na spectrum dị larịị iji kọwaa njirimara elu mfu ya nke ọma. Karịsịa, grating eriri acousto-optical nke e wuru site na iji mmetụta acousto-optical nwere ike iru oke nhazi nke ogologo mfu resonant ruo 1000 nm site na nhazi eletriki. Ya mere, nnwale grating siri ike nke nwere oke nhazi dị otú ahụ na-eweta nnukwu ihe ịma aka na oke bandwit nke isi iyi ọkụ spectrum sara mbara. N'otu aka ahụ, n'afọ ndị na-adịbeghị anya, ejiriwo grating eriri Bragg nke a gbagọrọ agbagọ mee ihe n'ọhịa nke nchọpụta eriri. N'ihi njirimara ya dị iche iche maka mfu, oke nkesa ebili mmiri nwere ike iru 40 nm. Usoro mmetụta ya na-abụkarị iji tụnyere mmegharị dị n'etiti ọtụtụ elu nnyefe, yabụ ọ dị mkpa ịtụle spectrum nnyefe ya kpamkpam. A chọrọ ka bandwit na ike nke isi iyi ọkụ spectrum sara mbara dị elu.
2. Ọnọdụ nyocha n'ụlọ na mba ofesi
2.1 Isi iyi ọkụ laser dị warara nke nwere obosara ahịrị
2.1.1 Laser nke kesara nzaghachi semiconductor dị warara n'obosara ahịrị
Na 2006, Cliche na ndị otu ya belatara nha MHz nke semiconductor.Laser DFB(laser nzaghachi kesara) na nha kHz site na iji usoro nzaghachi eletriki; Na 2011, Kessler na ndị otu ya jiri obere okpomọkụ na nnukwu nkwụsi ike jikọtara ya na njikwa nzaghachi na-arụ ọrụ iji nweta mmepụta laser obosara 40 MHz nke ukwuu; Na 2013, Peng na ndị otu ya nwetara mmepụta laser semiconductor nwere obosara 15 kHz site na iji usoro mgbanwe nzaghachi Fabry-Perot (FP) mpụga. Usoro nzaghachi eletriki jiri nzaghachi Pond-Drever-Hall nke ọma iji mee ka obosara line laser nke isi iyi ọkụ belata. Na 2010, Bernhardi na ndị otu ya mepụtara 1 cm nke alumina FBG nke erbium-doped na silicon oxide substrate iji nweta mmepụta laser nwere obosara ahịrị nke ihe dị ka 1.7 kHz. N'otu afọ ahụ, Liang na ndị otu ya. jiri nzaghachi onwe onye nke Rayleigh scattering azụ nke ihe na-eme ka mgbidi olu olu dị elu nke Q mepụtara maka mkpakọ laser semiconductor obosara, dịka egosiri na Foto 1, wee mechaa nweta mmepụta laser dị warara nke 160 Hz.
Foto nke 1 (a) Eserese nke mkpakọ laser semiconductor linewidth dabere na mgbasa Rayleigh nke mpụta na-agba n'ime ahụ nke resonator gallery mode na-eme mkpọtụ;
(b) Ugboro ugboro nke laser semiconductor na-agba ọsọ n'efu nke nwere obosara ahịrị nke 8 MHz;
(c) Ugboro ugboro nke laser ahụ nke nwere obosara ahịrị agbakọrọ ruo 160 Hz
2.1.2 Eriri laser dị warara nke nwere obosara ahịrị
Maka laser eriri oghere dị larịị, a na-enweta mmepụta laser dị warara nke ụdị ogologo otu site na ibelata ogologo nke resonator na ịbawanye oge ụdị ogologo. Na 2004, Spiegelberg et al. nwetara mmepụta laser dị warara nke otu ụdị ogologo nwere obosara 2 kHz site na iji usoro oghere dị mkpụmkpụ DBR. Na 2007, Shen et al. jiri eriri silicon erbium nke dị sentimita 2 nke ukwuu dee FBG na eriri fotosensitive Bi-Ge, ma jikọta ya na eriri na-arụ ọrụ iji mepụta oghere dị warara, na-eme ka obosara ahịrị mmepụta laser ya dị obere karịa 1 kHz. Na 2010, Yang et al. jiri oghere dị mkpụmkpụ dị sentimita 2 nke nwere doped nke ukwuu yana nzacha FBG dị warara iji nweta mmepụta laser otu ụdị ogologo nwere obosara ahịrị nke na-erughị 2 kHz. Na 2014, ndị otu ahụ jiri obere oghere dị larịị (resonator mgbanaka apịachiri apịachi) jikọtara ya na nzacha FBG-FP iji nweta mmepụta laser nwere obosara ahịrị dị warara, dịka egosiri na Foto nke 3. Na 2012, Cai et al. jiri usoro oghere dị mkpụmkpụ 1.4cm nweta mmepụta laser polarizing nwere ike mmepụta karịrị 114 mW, ogologo ebili mmiri etiti nke 1540.3 nm, na obosara ahịrị nke 4.1 kHz. Na 2013, Meng et al. jiri mgbasa Brillouin nke eriri erbium-doped nwere oghere mgbanaka dị mkpụmkpụ nke ngwaọrụ nchekwa zuru oke iji nweta mmepụta laser mkpọtụ otu-ogologo, obere-phase phase nwere ike mmepụta nke 10 mW. Na 2015, ndị otu ahụ jiri oghere mgbanaka nke eriri erbium-doped 45 cm dị ka ihe na-eme ka Brillouin gbasaa gain iji nweta obere oke na mmepụta laser dị warara.
Foto nke 2 (a) Ihe osise eserese nke laser eriri SLC;
(b) Ọdịdị ahịrị nke akara heterodyne nke ejiri igbu oge eriri 97.6 km tụọ
Oge ozi: Nọvemba-20-2023