Reflex telescopes: piav qhia, khoom siv, keeb kwm ntawm kev tsim

Cov txheej txheem:

Reflex telescopes: piav qhia, khoom siv, keeb kwm ntawm kev tsim
Reflex telescopes: piav qhia, khoom siv, keeb kwm ntawm kev tsim
Anonim

Txawm hais tias lub tsom iav tsom iav ua rau lwm hom kev hloov kho qhov muag, qhov no yog tus qauv tsim uas tuaj yeem ua tiav lub hom phiaj loj. Yuav luag txhua lub telescopes loj siv hauv kev tshawb fawb astronomical yog xws li. Reflecting telescopes tuaj nyob rau hauv ntau yam designs thiab tej zaum yuav siv cov khoom kho qhov muag ntxiv los txhim kho cov duab zoo los yog muab cov duab nyob rau hauv ib tug mechanically zoo txoj hauj lwm.

reflex telescopes
reflex telescopes

Tus yam ntxwv ntawm kev cuam tshuam lub koob yees duab

Lub tswv yim uas cov iav nkhaus coj zoo li lo ntsiab muag rov qab mus rau qhov tsawg kawg yog Alphazen's 11th-century treatise on optics, ib txoj hauj lwm uas nthuav dav hauv Latin txhais lus nyob rau hauv cov teb chaws Europe niaj hnub no. Tsis ntev tom qab lub invention ntawm lub refracting telescope los ntawm Galileo, Giovanni Francesco Sagredo thiab lwm tus neeg, tshwm sim los ntawm lawv cov kev paub txog lub hauv paus ntsiab lus ntawm nkhaus iav, sib tham txog lub tswv yim ntawm tsim ib lub tsom iav raj siv daim iav nyob rau hauv.raws li ib qho cuab yeej imaging. Bolognese Cesare Caravaggi tau tshaj tawm tias tau tsim thawj lub tsom iav qhov muag nyob ib ncig ntawm 1626. Tus kws tshaj lij Italian Niccolo Zucci, hauv kev ua haujlwm tom qab, tau sau tias nws tau sim nrog daim iav bronze hauv xyoo 1616, tab sis hais tias nws tsis muab cov duab txaus siab.

History of Creation

Qhov txiaj ntsig zoo ntawm kev siv cov iav parabolic, feem ntau txo qis ntawm qhov sib txawv ntawm qhov tsis muaj chromatic aberration, tau coj mus rau ntau qhov kev tsim qauv rau lub koob yees duab yav tom ntej. Qhov tseem ceeb tshaj plaws yog James Gregory, uas tau luam tawm cov qauv tsim tshiab rau lub tsom iav raj "reflecting" hauv xyoo 1663. Nws siv kaum xyoo (1673) ua ntej tus kws tshawb fawb sim Robert Hooke tuaj yeem tsim lub koob yees duab hom no, uas tau los ua lub npe hu ua Gregorian telescope.

Isaac Newton feem ntau tau txais txiaj ntsig los ntawm kev tsim thawj lub tsom iav qhov muag-refracting hauv xyoo 1668. Nws siv lub iav hlau kheej kheej kheej kheej thiab ib kab pheeb suab me me hauv kev teeb tsa kho qhov muag, hu ua Newtonian telescope.

reflecting telescopes
reflecting telescopes

Kev txhim kho ntxiv

Txawm hais tias qhov kev xav zoo ntawm kev siv lub teeb pom kev zoo, kev tsim qauv tsis yooj yim thiab kev ua haujlwm tsis zoo ntawm cov iav hlau siv lub sijhawm txhais tau tias nws siv sijhawm ntau dua 100 xyoo rau lawv los ua neeg nyiam. Ntau qhov kev nce qib hauv kev xav txog kev tsom iav tsom iav suav nrog kev txhim kho hauv kev tsim cov iav parabolic hauv xyoo pua 18th.xyoo pua, nyiaj-coated iav iav nyob rau hauv lub xyoo pua puv 19, ruaj aluminium coatings nyob rau hauv lub xyoo pua 20th, segmented tsom iav kom muab cov diameters loj dua, thiab active optics los them rau gravitational deformation. Ib nrab xyoo pua 20th innovation yog catadioptic telescopes xws li Schmidt lub koob yees duab, uas siv ob lub iav kheej kheej thiab lub lens (hu ua lub phaj corrector) ua cov ntsiab lus kho qhov muag, feem ntau yog siv rau cov duab loj loj yam tsis muaj qhov sib txawv.

Thaum kawg ntawm lub xyoo pua 20th, kev txhim kho ntawm kev hloov kho qhov muag thiab kev ua tiav cov duab kom kov yeej cov teeb meem cuam tshuam nrog kev soj ntsuam thiab kev xav ntawm lub tsom iav raj yog muaj nyob rau hauv qhov chaw telescopes thiab ntau hom khoom siv dav hlau kos duab.

Cov yam ntxwv ntawm kev cuam tshuam telescopes
Cov yam ntxwv ntawm kev cuam tshuam telescopes

Daim iav curvilinear yog lub ntsiab kho qhov muag ntawm lub tsom iav, thiab nws tsim cov duab hauv lub dav hlau focal. Qhov kev ncua deb ntawm daim iav mus rau lub dav hlau focal yog hu ua focal length. Lub ntsuas hluav taws xob digital tuaj yeem muab tso rau ntawm no los sau cov duab, lossis ib daim iav ntxiv tuaj yeem ntxiv los hloov cov yam ntxwv kho qhov muag thiab / lossis hloov lub teeb rau zaj duab xis, digital sensor, lossis eyepiece rau kev pom kev pom.

Kev piav qhia ntxaws

Daim iav tseem ceeb hauv lub tshuab tsom iav niaj hnub no feem ntau muaj cov iav lub tog raj kheej uas nws sab pem hauv ntej yog hauv av mus rau ib tus kheej kheej lossis parabolic. Ib txheej nyias ntawm aluminium yog evacuated mus rau lub lens, tsimReflective thawj nto daim iav.

Qee lub koob yees duab siv cov iav thawj uas tsim txawv. Lub molten iav rotates kom nws nto paraboloidal, nws txias thiab solidifies. Cov duab iav uas tau tshwm sim kwv yees li qhov xav tau paraboloid zoo, uas yuav tsum tau sib tsoo tsawg thiab polishing kom ua tiav daim duab raug.

Newtonian reflecting telescope
Newtonian reflecting telescope

Image quality

Reflector telescopes, zoo li lwm yam kev kho qhov muag, tsis tsim cov duab "zoo tagnrho". Qhov yuav tsum tau yees duab ntawm qhov deb mus rau infinity, saib lawv ntawm qhov sib txawv wavelengths ntawm lub teeb, thiab xav tau qee txoj hauv kev los saib cov duab uas lub iav thawj tsim tau txhais tau hais tias ib txwm muaj qee qhov kev cuam tshuam hauv kev tsim kho qhov muag ntawm lub tsom iav tsom iav.

Vim tias daim iav thawj tsom lub teeb rau ib qho chaw nyob rau hauv pem hauv ntej ntawm nws tus kheej lub ntsej muag, yuav luag tag nrho cov tsom iav tsom iav tsom iav muaj lub iav thib ob, tus tuav zaj duab xis, lossis lub ntsuas ntsuas ze ntawm qhov chaw focal no, ib feem tiv thaiv lub teeb kom ncav cuag qhov tseem ceeb. iav. Qhov no tsis yog tsuas yog ua rau qee qhov txo qis ntawm lub teeb uas lub kaw lus khaws cia, tab sis kuj ua rau poob qhov sib txawv ntawm cov duab vim muaj qhov cuam tshuam cuam tshuam, nrog rau qhov sib txawv ntawm qhov sib txawv tshwm sim los ntawm cov qauv kev txhawb nqa thib ob.

reflecting telescope ntaus ntawv
reflecting telescope ntaus ntawv

Kev siv cov iav tsis txhob chromatic aberration,tab sis lawv tsim lwm hom aberrations. Daim iav yooj yim kheej kheej tsis tuaj yeem xa lub teeb los ntawm qhov khoom nyob deb mus rau qhov pom tseeb, vim hais tias qhov kev xav ntawm lub teeb ci tawm tsam daim iav ntawm nws ntug tsis sib haum nrog cov uas cuam tshuam los ntawm qhov nruab nrab ntawm daim iav, qhov tsis xws luag hu ua spherical aberration. Txhawm rau zam qhov teeb meem no, qhov zoo tshaj plaws xav txog lub tsom iav raj tsim siv cov iav tsom iav uas tuaj yeem nqa tag nrho lub teeb mus rau qhov pom tseeb.

Reflector thiab nws cov ntsiab lus
Reflector thiab nws cov ntsiab lus

YGregorian Telescope

Lub Gregorian telescope yog piav qhia los ntawm Scottish astronomer thiab lej James Gregory hauv nws phau ntawv 1663 Optica Promota raws li siv daim iav thib ob uas qhia txog cov duab los ntawm lub qhov hauv daim iav thawj. Qhov no tsim cov duab ntsug muaj txiaj ntsig zoo rau kev soj ntsuam hauv av. Muaj ntau lub koob yees duab niaj hnub loj uas siv Gregorian teeb tsa.

Newton's Reflector Telescope

Newton lub cuab yeej yog thawj qhov ua tau zoo ntawm lub tsom iav, ua los ntawm Isaac xyoo 1668. Nws feem ntau muaj paraboloid thawj, tab sis ntawm focal ratios ntawm f / 8 los yog ntau tshaj, ib tug spherical thawj, uas tej zaum yuav txaus rau siab pom kev daws teeb meem. Ib lub tiaj tiaj tiaj ua rau pom lub teeb ntawm lub dav hlau focal ntawm sab saum toj ntawm lub telescope raj. Qhov no yog ib qho ntawm cov qauv yooj yim tshaj plaws thiab kim tshaj plaws rau cov khoom siv raw, thiab yog ib qho ntawm cov neeg nyiam nyiam. Txoj kab hluav taws xob ntawm kev cuam tshuam lub tsom iav raj yog thawj zaugtau ua tiav qhov tseeb ntawm tus qauv Newtonian.

loj tshaj plaws reflecting telescope
loj tshaj plaws reflecting telescope

Cassegrain Apparatus

Lub Cassegrain telescope (qee zaus hu ua "classical Cassegrain") tau tsim ua ntej xyoo 1672, ntaus nqi rau Laurent Cassegrain. Nws muaj lub hauv paus parabolic thiab ib qho hyperbolic theem nrab uas qhia txog lub teeb rov qab thiab nqis los ntawm lub qhov hauv thawj.

Tus tsim ntawm Dall-Kirkham Cassegrain telescope yog tsim los ntawm Horace Dall nyob rau hauv 1928, thiab tau muaj npe nyob rau hauv ib tsab xov xwm luam tawm nyob rau hauv Scientific American nyob rau hauv 1930 tom qab kev sib tham ntawm amateur astronomer Allan Kirkham thiab Albert G. Ingalls, (the magazine tus editor ntawm lub sijhawm). Nws siv lub concave elliptical thawj thiab convex theem nrab. Thaum cov txheej txheem no yooj yim dua los zom dua li cov Cassegrain classic lossis Ritchey-Chrétien system, nws tsis haum rau kev tsis nco qab. Lub curvature ntawm daim teb yog tiag tiag tsawg tshaj li ntawm classical Cassegrain. Niaj hnub no, qhov kev tsim no yog siv nyob rau hauv ntau daim ntawv thov ntawm cov khoom zoo. Tab sis nws tau raug hloov los ntawm cov khoom siv hluav taws xob. Txawm li cas los xij, nws yog cov cuab yeej no uas suav tias yog lub tsom iav loj tshaj plaws.

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