Kev txhais ntawm daim iav concave
Ib hom iav uas siv hauv lub neej txhua hnub yog daim iav concave. Daim iav concave yog daim iav uas zoo li nkhaus, qhov twg qhov saum npoo ntawm daim iav ci ntsa iab rov qab.
Kev siv ntawm daim iav concave
Yog tias koj xav saib koj daim tawv nqaij ntawm lub ntsej muag kom meej dua thiab ntxaws ntxaws, kaw koj lub ntsej muag rau ntawm daim iav concave uas
cuam tshuam lub teeb kom daim duab ntawm koj lub ntsej muag zoo li loj dua thiab cov qhov hws ntawm daim tawv nqaij ntawm lub ntsej muag tuaj yeem pom tseeb. Daim duab ntawm koj lub ntsej muag zoo li loj dua koj lub ntsej muag vim tias daim iav ua rau daim duab loj dua, qhov no tshwm sim thaum qhov deb ntawm koj lub ntsej muag ntawm daim iav concave me dua qhov ntev ntawm daim iav. Vim tias nws tuaj yeem ua rau cov duab loj dua, cov iav concave feem ntau yog siv los ntawm cov poj niam los hnav khaub ncaws thiab siv los ntawm cov txiv neej thaum txiav plaub hau.
Cov iav kuj siv rau hauv cov teeb ci thiab lub teeb taub hau tsheb. Kev siv daim iav ntawm lub teeb ci, lub teeb taub hau tsheb, lossis lwm yam teeb pom kev zoo yog kom sib luag lub teeb kom txhua lub teeb tuaj yeem txav mus ncaj nraim. Yog tias koj qhib lub hau iav pem hauv ntej ntawm lub teeb ci thiab tso daim iav concave, lub teeb ci uas tshwm sim yuav dav rau txhua qhov kev taw qhia thiab tsis tuaj yeem ci cov khoom lossis qhov chaw ntawm txoj kev deb.
Ntxiv rau kev siv rau hauv teeb pom kev zoo lossis lwm yam teeb pom kev zoo, daim iav kuj tseem siv rau hauv cov chaw tsim hluav taws xob hnub ci. Hauv lub chaw tsim hluav taws xob hnub ci, daim iav concave sau lub hnub ci, thiab tag nrho lub teeb raug coj mus rau qhov chaw tseem ceeb ntawm daim iav, qhov twg ntawm qhov chaw tseem ceeb daim iav concave raug muab tso rau hauv lub thawv. Lub hnub ci siv los ua kom cov dej hauv lub thawv ua pa, qhov twg cov pa siv los tsav cov turbines tsim hluav taws xob.
Qhov chaw tseem ceeb ntawm daim iav concave
Yog tias qhov chaw ntawm daim iav concave uas cuam tshuam lub teeb raug rau ib yam khoom deb heev xws li lub hnub, ces lub teeb ci uas lub hnub tso tawm yuav sib luag rau lub axis tseem ceeb ntawm daim iav concave, raws li pom hauv daim duab hauv qab no. Lub axis tseem ceeb yog ib txoj kab ncaj nraim uas xav txog perpendicular rau qhov chaw nruab nrab ntawm qhov chaw ntawm daim iav concave. Hauv daim duab hauv qab no, cov kab axis tseem ceeb sib phim nrog qhov chaw ntawm kev sib tshuam ntawm txhua lub teeb ci ntsa iab.
Thaum nws ntaus rau saum npoo ntawm daim iav concave, txhua lub teeb ntawm lub teeb ua raws li txoj cai ntawm kev cuam tshuam ntawm lub teeb. Nruab nrab ntawm cov teeb ci ntsa iab thiab cov teeb ci ntsa iab, muaj ib txoj kab ib txwm perpendicular rau saum npoo ntawm daim iav uas dhau los ntawm lub teeb ci, tab sis txoj kab ib txwm tsis pom.
Lub kaum sab xis ntawm cov teeb ci ntsa iab thiab cov kab ib txwm yog tib yam li lub kaum sab xis ntawm cov teeb ci ntsa iab thiab cov kab ib txwm. Tsis zoo li daim iav dav hlau uas muaj qhov chaw tiaj tiaj kom txhua cov kab ib txwm nyob rau tib qho kev taw qhia, cov kab ib txwm ntawm daim iav concave tsis yog ib qho kev taw qhia vim tias qhov chaw ntawm daim iav concave yog nkhaus thiab tsis tiaj tus. Tag nrho cov kab rov tav cuam tshuam ntawm ib qho chaw uas sib phim nrog lub axis tseem ceeb, hu ua qhov chaw tsom (F). Hauv lwm lo lus, qhov chaw tsom yog qhov chaw duab ntawm ib yam khoom uas nyob deb heev ntawm qhov chaw ntawm daim iav concave, xws li lub hnub thiab cov hnub qub.
Raws li txoj cai ntawm kev cuam tshuam ntawm lub teeb, qhov kev taw qhia ntawm lub teeb lossis lub teeb ci tuaj yeem thim rov qab, sib piv rau daim duab dhau los. Yog tias xav tias lub teeb ci nyob ntawm qhov chaw tseem ceeb ntawm daim iav concave, lub teeb ci uas tawm los ntawm cov khoom raug cuam tshuam los ntawm qhov chaw ntawm daim iav concave. Qhov kev taw qhia ntawm lub teeb ci cuam tshuam yog sib luag rau lub axis tseem ceeb ntawm daim iav concave. Qhov no yog lub hauv paus ntsiab lus tom qab kev siv cov iav concave ntawm lub teeb, lub teeb taub hau tsheb, lossis lwm yam teeb pom kev zoo, kev siv cov iav concave hauv cov chaw tsim hluav taws xob hnub ci.
Raws li cov lus piav qhia saum toj no, nws tuaj yeem xaus lus tias yog tias muaj lub teeb ci nyob ntawm qhov chaw tseem ceeb ntawm daim iav concave,
lub teeb ci ntsa iab uas lub khoom tso tawm los ntawm qhov chaw ntawm daim iav concave, qhov twg lub teeb ci ntsa iab yog sib luag rau lub axis tseem ceeb ntawm daim iav concave. Ntawm qhov tod tes, yog tias lub khoom nyob deb heev, daim duab ntawm lub khoom nyob ntawm qhov chaw tseem ceeb ntawm daim iav concave. Yog tias lub khoom nyob deb heev muaj daim duab ntawm qhov chaw tseem ceeb, daim duab ntawm lub khoom nyob qhov twg yog tias qhov deb ntawm lub khoom ntawm qhov chaw ntawm daim iav yog finite lossis ze? Txhawm rau nkag siab qhov no, thov kawm txog lub ntsiab lus ntawm kev tsim duab los ntawm daim iav concave.
Qhov ntev ntawm daim iav concave
Qhov ntev ntawm lub lens (f) yog qhov deb ntawm qhov chaw nruab nrab (F) thiab qhov chaw ntawm daim iav concave. Cov hauv qab no yog piav qhia txog yuav ua li cas txiav txim siab qhov ntev ntawm daim iav concave siv cov teeb ci ntsa iab thiab cov teeb ci ntsa iab.
Qhov C yog qhov chaw nruab nrab ntawm qhov nkhaus ntawm daim iav concave. Qhov ntev ntawm daim iav concave yog f (qhov ntev ntawm daim iav concave = f = FQ), thiab lub vojvoog ntawm qhov nkhaus ntawm daim iav concave yog r (curvature radius = r = CQ = CP).
Cov teeb ci ntsa iab uas ci ntsa iab rau ntawm daim iav P ces raug cuam tshuam mus rau qhov chaw tsom F. Txoj kab dashed CP yog txoj kab ib txwm. Cov teeb ci ntsa iab uas nkag los thiab cov teeb ci ntsa iab uas cuam tshuam ua tiav txoj cai ntawm kev cuam tshuam ntawm lub teeb, qhov twg lub kaum sab xis (θ) sib npaug rau lub kaum sab xis ntawm kev cuam tshuam (θ) thiab lub kaum sab xis no sib npaug rau lub kaum sab xis ntawm daim duab peb ceg PCQ (θ). Lub kaum sab xis ntawm daim duab peb ceg ntawm PCQ yog tib yam li lub kaum sab xis ntawm daim duab peb ceg CPF. Yog li ntawd, daim duab peb ceg PFC yog daim duab peb ceg sib npaug. Vim tias daim duab peb ceg PFC yog daim duab peb ceg sib npaug, qhov ntev ntawm PF sib npaug rau qhov ntev ntawm CF. Yog tias qhov dav ntawm daim iav me dua qhov radius ntawm qhov nkhaus ntawm daim iav, qhov ntev ntawm PF raug suav tias sib npaug rau qhov ntev ntawm FQ. Vim tias CF = PF thiab PF = FQ, ces CQ = 2 CF = 2 FQ. CQ = r = radius ntawm qhov nkhaus ntawm daim iav concave thiab FQ = f = focal length ntawm daim iav concave. Yog li, nws tuaj yeem xaus lus tias lub vojvoog ntawm qhov nkhaus ntawm daim iav concave (r) = 2 x qhov ntev ntawm lub lens (f) ntawm daim iav concave. Kev suav lej:
r = 2f los yog f = r / 2
Kev tsim duab los ntawm daim iav concave
Cov iav dav hlau tsuas yog tsim tau cov duab virtual xwb, thaum cov iav concave tuaj yeem tsim cov duab tiag tiag thiab cov duab virtual. Cov duab ntawm ib yam khoom yog tiag lossis virtual, nyob ntawm qhov deb ntawm cov khoom ntawm qhov chaw ntawm daim iav concave.
thiab qhov no tau piav qhia kom meej hauv cov ncauj lus ntawm kev tsim duab los ntawm daim iav concave.
Duab tiag tiag
Ib daim duab yog qhov tseeb yog tias lub teeb ci ntsa iab hla qhov chaw uas daim duab nyob. Yog tias lub vijtsam raug tso rau hauv qhov chaw uas muaj daim duab tiag tiag, nws yuav tshwm sim lub teeb ci ntsa iab ntawm lub vijtsam, thiab lub teeb ci no muaj cov duab ntawm ib yam khoom. Qhov muaj cov duab tiag tiag tsim los ntawm cov iav concave yog qhov laj thawj uas cov iav concave siv rau hauv cov tsom iav astronomical. Hais txog lub lens, koj yuav paub tias lub peev xwm ntawm lub lens los tsim ib daim duab tiag tiag yog qhov laj thawj rau kev siv lub lens ntawm lub tsom iav optical.
Duab virtual
Ib daim duab yog virtual yog tias lub teeb ci ntsa iab tsis hla dhau qhov chaw uas daim duab nyob. Yog tias lub vijtsam raug tso rau hauv qhov chaw uas muaj daim duab virtual, yuav tsis muaj lub teeb pom kev ntawm lub vijtsam. Daim duab virtual tsis muaj nyob, tab sis lub qhov muag tib neeg pom ib lub teeb ci txav mus rau hauv txoj kev ncaj kom nws zoo li lub teeb txav mus ncaj qha los ntawm qhov chaw uas daim duab nyob.
