Lub hauv paus ntawm Leica biological microscope
Txhawm rau txhim kho cov cuab yeej siv nrog lub zog daws teeb meem siab dua, pab pawg tshawb fawb tshawb fawb ntawm Leica Microscope yuav tsum nrhiav cov khoom siv hluav taws xob luv luv 6t thiab "lens" uas tuaj yeem tsom thiab tswj nws. Lub tshuab ntsuas hluav taws xob raws li lub hauv paus ntsiab lus ntawm electron optics yog ib qho cuab yeej. Lub npe hu ua electron optics yog hais txog kev qhuab qhia uas kawm thiab siv cov deflection, tsom thiab duab cov cai ntawm electron flow. Nws yog nyob ntawm peb qhov kev tshawb pom hauv qab no;
(ib). J. J. Thomson (1872) ua pov thawj qhov muaj nyob ntawm electrons;
(ob tug). L. deBroglie's (1923) corollary rau particle-wave duality ntawm teeb meem'
(3). H.Busch (1926) nrhiav pom cov nyhuv lensing ntawm axisymmetrically faib hluav taws xob thiab sib nqus teb ntawm cov khoom them.
Ua ntej, cia peb tham txog cov teeb pom kev zoo hauv Leica biological microscope-electron flow. Raws li cov khoom saum toj no (1) thiab (2), peb tuaj yeem xav txog qhov txav hluav taws xob ntws raws li cov hluav taws xob nthwv dej, uas nce mus rau cov kev taw qhia ntawm electron txav ntawm qhov ceev tsis tu ncua thiab sinusoidally hloov nrog lub sijhawm. Xyoo 1927, D9v tau lees paub qhov tsis muaj zog ntawm cov hluav taws xob ntau dua li qhov tshwm sim ntawm electron diffraction tshwm sim los ntawm On thiab Germer, thiab tom qab ntawd ntsuas thiab txheeb xyuas cov qauv sib txheeb. Txhawm rau xam cov electron wavelength, peb xav tias qhov loj yog M thiab tus nqi yog (ib') Cov electrons muaj xoom tshaj tawm. Thaum nws hla ib cheeb tsam uas muaj peev xwm hloov ntawm o mus rau Yo, qhov nrawm dhau los ?. Yog li ntawd, lub zog thiab lub zog kinetic x ntawm electrons yog feem ntau: Thaum kawg, qhov kev qhia ntawm electron wavelength tuaj yeem tau txais: Nws yuav tsum tau taw qhia tias rau cov hluav taws xob txav ntawm kev kub ceev, lawv cov huab hwm coj yuav nce nrog kev nce ceev. Piv txwv li, thaum lub zog ceev yo=lookV, cov yam ntxwv ntawm hluav taws xob hloov pauv los ntawm 5 feem pua. Vim li no, qhov kev sib raug zoo ntawm cov khoom siv hluav taws xob yuav tsum raug txiav txim siab. Cov mis hloov kho yog: nyob rau hauv cov mis, chav tsev ntawm lub electron wavelength A yog M, thiab chav tsev ntawm relativistic kho voltage vL yog tuav). Cov piv txwv hauv qab no qhia txog kev sib raug zoo ntawm electron wavelength thiab accelerating voltage
Lwm qhov tsim nyog ntawm Leica biological microscope yog lub lens uas tuaj yeem tsom lub teeb hluav taws xob - lub lens electron. Txhawm rau kom ua tau zoo piav qhia nws txoj hauv kev ua haujlwm, ib qho piv txwv yooj yim siv tau, uas yog, lub tog raj kheej ntev hollow ua los ntawm helical kauj, tseem hu ua ntev solenoid. Thaum ib tug tam sim no dhau los ntawm xws li ib tug coil, ib tug kwv yees li niaj hnub magnetic teb yog generated nyob ze nws central axis. Raws li txhais tes txoj cai, qhov no magnetic teb yog raws li lub twj tso kua mis (Z) kev taw qhia. Thaum lub high-speed tsiv electrons (-') nkag mus rau thaj chaw no, lawv yuav raug cuam tshuam los ntawm krentan quab yuam (kev phem) ntawm cov hlau nplaum. Nws yog proportional rau tus ntoo khaub lig khoom tus nqi ntawm lub electron tshaj tawm thiab lub magnetic teb zog, uas yog, kaum txhiab=ib Mx kaum txhiab. Qhov pib tshaj tawm ntawm electrons nkag mus rau thaj tsam sib nqus; Nws tuaj yeem muab faib ua ob ntu los tham txog xeev =seat l. Lub nrawm sib npaug mus rau cov kev taw qhia ntawm lub magnetic teb yog 5z, thiab nws lub zog nrog lub magnetic teb yog xoom, yog li qhov ceev ntawm electrons raws li axial kev taw qhia yuav tsis hloov. Lub zog sib nqus ntawm lub nrawm tivthaiv 5L perpendicular mus rau cov kev taw qhia ntawm lub magnetic teb tsis yog tsuas yog perpendicular mus rau cov kev taw qhia ntawm lub ceev tivthaiv, tab sis kuj perpendicular mus rau cov kev taw qhia ntawm lub magnetic teb, yog li nws yog ib tug uniform centripetal quab yuam. Qhov kawg tshwm sim yog tias cov hluav taws xob txav mus rau hauv ib qho kev sib tw ncig ib ncig ntawm lub hauv paus axis thaum nce mus raws qhov nyuaj, thiab lawv qhov kev sib tw spatial yog ib txoj kab helical.
Leica microscope tuaj yeem ua pov thawj tias cov khoom siv hluav taws xob nrog qhov sib txawv pib tshaj tawm tawm los ntawm tib yam khoom taw tes (khoom) yuav sib sau ua ke ntawm tib qho duab taw tes (Pf) tom qab qee qhov kev ncua deb. Qhov no yog qhov qauv ntawm lub lens magnetic. Nws yuav tsum tau muab sau tseg tias qhov kev sib cuag lo ntsiab muag muaj lub luag haujlwm ntawm kev sib hloov thiab sib hloov (kev ntsuas) cov electrons txav ntawm kev kub ceev. Electron trajectories nyob rau hauv ib tug uniform magnetic teb.
Electron lo ntsiab muag hauv Leica biological microscopes tuaj yeem yog electrostatic lossis (electro) magnetic. Nws yog lub lens electrostatic tsim los ntawm ntau lub electrodes, uas muaj cov kev xav tau siab rau kev tiv thaiv thiab lub tshuab nqus tsev. Tam sim no, (electro) magnetic lo ntsiab muag feem ntau yog siv. Tsuas yog tus qauv tsim thiab cov qauv ntawm lub lens tuaj yeem sib txawv raws li qhov xav tau sib txawv ntawm ntau txoj haujlwm.
