Transmission Electron Microscope Kev ua haujlwm yam ntxwv
1. Kev ruaj ntseg
Kev ruaj ntseg ntawm lub raj photomultiplier yog txiav txim siab los ntawm ntau yam xws li cov yam ntxwv ntawm cov cuab yeej nws tus kheej, lub xeev kev khiav hauj lwm thiab ib puag ncig. Muaj ntau qhov xwm txheej uas qhov tso zis ntawm lub raj tsis ruaj khov thaum lub sijhawm ua haujlwm, feem ntau:
ib. Cov vuam tsis zoo ntawm cov electrodes hauv lub raj, cov qauv xoob, kev sib cuag tsis zoo ntawm cathode shrapnel, inter-pole tip discharge, hluav taws dhia thiab lwm yam kev dhia tsis ruaj khov tshwm sim los ntawm cov teeb liab loj thiab me.
b. Txuas ntxiv thiab qaug zog instability tshwm sim los ntawm qhov loj heev anode tso zis tam sim no.
c. Cov nyhuv ntawm ib puag ncig tej yam kev mob rau stability. Lub raj rhiab heev yuav txo qis thaum qhov kub thiab txias nce.
d. Qhov chaw ntub dej ua rau muaj qhov sib txawv ntawm cov pins, uas ua rau muaj zog tam sim no thiab tsis ruaj khov.
e. Environmental electromagnetic teb cuam tshuam ua rau tsis muaj kev ruaj ntseg.
2.Limit ua hauj lwm voltage
Txwv kev khiav hauj lwm voltage yog qhov txwv siab tshaj ntawm qhov voltage tso cai rau siv rau lub raj. Siab dua qhov hluav taws xob no, lub raj xa tawm lossis txawm tias tawg.
Daim ntawv thov
Vim qhov nce siab thiab lub sij hawm teb luv luv ntawm lub raj photomultiplier, thiab vim tias nws cov zis tam sim no yog proportional rau tus naj npawb ntawm photons, nws yog dav siv hauv astrophotometric thiab astro-spectrophotometry. Nws qhov zoo yog: qhov ntsuas qhov tseeb siab, muaj peev xwm ntsuas cov khoom tsis zoo, thiab muaj peev xwm ntsuas kev hloov pauv sai hauv astronomical luminosity. Hauv astronomical photometry, qhov dav siv ntau dua yog antimony cesium photocathode multiplier raj, xws li RCA1p21. Qhov zoo quantum efficiency ntawm no photomultiplier raj yog nyob ib ncig ntawm 4200Å, uas yog hais txog 20%. Kuj tseem muaj photomultiplier nrog ob npaug alkali photocathode, xws li GDB-53, uas muaj lub teeb liab-rau- suab nrov piv ib qho kev txiav txim siab loj dua li ntawm RCA1p21, nrog rau qhov tsis tshua muaj qhov tsaus ntuj tam sim no. Txhawm rau soj ntsuam thaj tsam ze-infrared, feem ntau siv ntau lub hauv paus photocathode thiab gallium arsenide cathode photomultiplier raj, qhov kawg quantum efficiency txog li 50%.
Cov raj photomultiplier tsuas tuaj yeem ntsuas ib qho ntawm cov ntaub ntawv ntawm ib lub sijhawm, piv txwv li, cov xov tooj yog 1. matrix. Vim tias tus naj npawb ntawm cov channel raug txwv los ntawm cov hlau zoo hlau nyob rau hauv qhov kawg ntawm anode, tsuas yog ntau pua ntawm cov channel tuaj yeem ua tau.
