Sannu kowa da kowa.
Rigima ce ta sa na rubuta wannan gajeriyar labarin a game da zaɓin TV.
Yanzu a cikin wannan yanki - da kuma "megapixels don kyamarori" - akwai bacchanalia na tallace-tallace a cikin neman shawarwari: HD Ready an dade da maye gurbinsa da Full HD, kuma 4K har ma 8K sun riga sun zama sananne.
Bari mu gane abin da gaske muke bukata?
Kwas ɗin ilimin lissafi na makaranta da wasu ilimin asali daga Wikipedia zasu taimake mu da wannan.
Don haka a cewar , ido tsirara na matsakaicin mutum wata na'ura ce ta musamman wacce ke da ikon kallon sarari lokaci guda a kusurwar 130 ° -160 °, da kuma rarrabe abubuwa a kusurwar 1-2′ (kimanin 0,02°-0,03°). . Inda Saurin mayar da hankali yana faruwa a nesa na 10 cm (matasa) - 50 cm (mafi yawan mutane 50 shekaru da haihuwa) zuwa rashin iyaka..
Yayi kyau. A gaskiya, ba haka ba ne mai sauki.
Da ke ƙasa akwai filin kallon idon dama na mutum (katin perimetric, lambobi akan sikelin sune digiri na kusurwa).
Wurin ruwan lemu shine wurin tsinkayar wurin makafi na fundus. Filin hangen nesa na ido ba shi da siffar da'irar yau da kullun, saboda iyakancewar ido ta hanci a gefen tsakiya da fatar ido sama da ƙasa.
Idan muka fifita hoton idanun dama da hagu, muna samun wani abu kamar haka:
Abin baƙin ciki shine, idon ɗan adam ba ya samar da ingancin gani iri ɗaya a duk faɗin jirgin a kusurwa mai faɗi. Ee, tare da idanu biyu za mu iya gane abubuwa a cikin ɗaukar hoto na 180 ° a gabanmu, amma za mu iya gane su a matsayin nau'i uku kawai a cikin 110 ° (zuwa yankin kore), kuma a matsayin masu cikakken launi - a cikin ko da ma. ƙaramin kewayon kusan 60°-70° (zuwa yankin shuɗi). Haka ne, wasu tsuntsaye suna da filin kallon kusan 360 °, amma muna da abin da muke da shi.
Ta haka muke samun hakan mutum yana karɓar hoto mafi inganci a kusurwar kallo na kusan 60°-70°. Idan ana buƙatar ƙarin ɗaukar hoto, ana tilasta mana mu “gudu” idanunmu a kan hoton.
Yanzu - game da TVs. Ta hanyar tsohuwa, yi la'akari da TVs tare da mafi mashahuri nisa-zuwa-tsayi rabo kamar 16:9, kazalika da allo mai lebur.
Wato, yana fitowa cewa W: L = 16:9, kuma D shine diagonal na allo.
Don haka, tunawa da Dokar Pythagorean:
Don haka, a ɗauka cewa ƙuduri shine:
- HD Shirye 1280x720 pixels
- Cikakken HD yana da 1920 x 1080 pixels
- Ultra HD 4K yana da 3840x2160 pixels,
mun gano cewa gefen pixel shine:
- HD Shirye: D/720,88
- Cikakken HD: D/2202,91
- Ultra HD 4K: D/4405,81
Ana iya samun lissafin waɗannan ƙimar anan
Yanzu bari mu lissafta mafi kyawun nisa zuwa allon don ido ya rufe dukkan hoton.
Daga adadi ya bayyana a sarari cewa
Tunda mafi girman ma'aunin tsayi da faɗin hoton shine faɗin - kuma ido yana buƙatar rufe dukkan faɗin allon - bari mu ƙididdige mafi kyawun nisa zuwa allon, la'akari da cewa, kamar yadda aka nuna a sama, kusurwar kallo. kada ya wuce digiri 70:
Wato: Domin ido ya rufe dukkan faɗin allon, dole ne mu kasance a nesa ba kusa da kusan rabin diagonal na allon ba.. Haka kuma, wannan nisa dole ne ya zama aƙalla 50 cm don tabbatar da mai da hankali ga mutane na kowane zamani. Mu tuna da wannan.
Yanzu bari mu lissafta tazarar da mutum zai bambanta pixels akan allon. Wannan triangle iri ɗaya ne tare da tangent na kwana, R kawai a wannan yanayin shine girman pixel:
Wato: a nesa fiye da 2873,6 pixel masu girma dabam, ido ba zai ga hatsi ba. Wannan yana nufin, la'akari da lissafin gefen pixel da ke sama, kuna buƙatar kasancewa a mafi ƙarancin nisa daga allon don hoton ya zama al'ada:
- HD Shirye: D/720,88 x 2873,6 = 4D, wato, diagonal na allo guda huɗu
- Cikakken HD: D/2202,91 x 2873,6 = 1,3D, wato, kusan ƙasa da ɗaya da rabi diagonal na allo.
- Ultra HD 4K: D/4405,81 x 2873,6 = 0,65D, wato, dan kadan fiye da rabin diagonal na allo.
Kuma yanzu abin da duk ya kai ga -
Ƙarshe:
- Kada ku zauna kusa da 50 cm zuwa allon - ido ba zai iya mayar da hankali kan hoton kullum ba.
- Kada ku zauna kusa da diagonal na allo sama da 0,63 - idanunku za su gaji saboda dole ne su zagaye hoton.
- Idan kuna shirin kallon talabijin a nesa fiye da diagonal na allo guda huɗu, bai kamata ku sayi wani abu mai sanyaya fiye da HD Ready ba - ba za ku lura da bambanci ba.
- Idan kuna shirin kallon talabijin a nesa sama da diagonal na allo ɗaya da rabi, bai kamata ku sayi wani abu mai sanyaya fiye da Cikakken HD ba - ba za ku lura da bambanci ba.
- Yin amfani da 4K yana da kyau kawai idan kun kalli allon a nesa da diagonal kasa da ɗaya da rabi, amma fiye da rabin diagonal. Wataƙila waɗannan wasu nau'ikan nau'ikan na'urori ne na wasan kwamfuta ko manyan bangarori, ko kujera da ke kusa da TV.
- Yin amfani da ƙuduri mafi girma ba ya da ma'ana - ko dai ba za ku ga bambanci da 4K ba, ko kuma za ku kasance kusa da allon kuma kusurwar kallo ba za ta rufe dukkan jirgin ba (duba aya 2 a sama). Ana iya magance matsalar a wani bangare tare da allon mai lanƙwasa - amma ƙididdiga (mafi rikitarwa) ya nuna cewa wannan riba tana da shakku sosai.
Yanzu ina ba da shawarar auna ɗakin ku, wurin da gadon gado da kuka fi so, diagonal na TV da tunani: shin yana da ma'ana don ƙarin biya?
source: www.habr.com