T\u1eeb kh\u00f3a t\u00ecm ki\u1ebfm: H\u00e3y Tr\u1ea3 L\u1eddi Em T\u1ea1i Sao? \u2013 T\u1eadp 5 – Arkady Leokum<\/p>\n\n\n\n
Tivi l\u00e0 ch\u1eef vi\u1ebft t\u1eaft c\u1ee7a Television c\u00f3 ngh\u0129a l\u00e0 \u201cnh\u00ecn c\u00e1ch kh\u00f4ng\u201d. Truy\u1ec1n h\u00ecnh tr\u1ef1c ti\u1ebfp l\u00e0 truy\u1ec1n \u0111i h\u00ecnh \u1ea3nh nh\u1eefng g\u00ec \u0111ang di\u1ec5n ra v\u00e0 ng\u01b0\u1eddi \u1edf xa c\u0169ng nh\u00ecn th\u1ea5y ngay c\u00f9ng m\u1ed9t l\u00fac, ho\u1eb7c truy\u1ec1n \u0111i nh\u1eefng h\u00ecnh tr\u00ean cu\u1ed1n phim \u0111\u00e3 thu tr\u01b0\u1edbc. C\u00f9ng v\u1edbi h\u00ecnh \u1ea3nh, \u00e2m thanh c\u0169ng \u0111\u01b0\u1ee3c truy\u1ec1n theo c\u00f9ng m\u1ed9t l\u00fac.<\/p>\n\n\n\n
Ta n\u00ean hi\u1ec3u truy\u1ec1n h\u00ecnh kh\u00f4ng ph\u1ea3i l\u00e0 truy\u1ec1n \u201ct\u1ea5m\u201d h\u00ecnh xuy\u00ean qua kh\u00f4ng kh\u00ed m\u00e0 ch\u1ec9 l\u00e0 truy\u1ec1n c\u00e1c xung \u0111\u1ed9ng \u0111i\u1ec7n, c\u00e1c \u201cviba\u201d. \u0111\u01a1n gi\u1ea3n l\u00e0 th\u1ebf n\u00e0y: nh\u1eefng h\u00ecnh \u1ea3nh \u0111\u01b0\u1ee3c bi\u1ebfn \u0111\u1ed5i th\u00e0nh nh\u1eefng xung \u0111\u1ed9ng \u0111i\u1ec7n (electrical impulses) \u0111\u01b0\u1ee3c m\u00e1y ph\u00e1t truy\u1ec1n \u0111i. M\u00e1y thu h\u00ecnh thu l\u1ea1i nh\u1eefng xung \u0111\u1ed9ng \u0111i\u1ec7n \u0111\u00f3 v\u00e0 bi\u1ebfn \u0111\u1ed5i l\u1ea1i th\u00e0nh h\u00ecnh. \u0111\u1ea1i kh\u00e1i v\u1eadn h\u00e0nh \u1ea5y nh\u01b0 th\u1ebf n\u00e0y:<\/p>\n\n\n\n
Giai \u0111o\u1ea1n 1: \u1ed1ng k\u00ednh thu h\u00ecnh thu l\u1ea1i \u00e1nh s\u00e1ng tr\u00ean h\u00ecnh (hay quang c\u1ea3nh) \u0111\u01b0a v\u00e0o t\u1ea5m ki\u1ebfng b\u1eaft h\u00ecnh (light sensitive plate of glass). T\u1ea5m ki\u1ebfng n\u00e0y ph\u00f3ng ra c\u00e1c \u0111i\u1ec7n t\u1eed. \u1ede nh\u1eefng \u0111i\u1ec3m \u201ctr\u1eafng\u201d tr\u00ean h\u00ecnh, n\u00f3 ph\u00f3ng ra \u0111\u01b0\u1ee3c nhi\u1ec1u electron h\u01a1n \u1edf nh\u1eefng \u0111i\u1ec3m \u201c\u0111en\u201d. Nh\u1eefng electron n\u00e0y \u0111\u01b0\u1ee3c thu l\u1ea1i tr\u00ean t\u1ea5m \u201cm\u1ee5c ti\u00eau\u201d.<\/p>\n\n\n\n
Giai \u0111o\u1ea1n 2: trong \u1ed1ng c\u1ee7a m\u00e1y thu, \u1edf \u0111\u1ea7u kia so v\u1edbi t\u1ea5m m\u1ee5c ti\u00eau c\u00f3 m\u1ed9t \u201ckh\u1ea9u s\u00fang \u0111i\u1ec7n t\u1eed\u201d b\u1eafn ra nh\u1eefng tia v\u1ec1 ph\u00eda t\u1ea5m m\u1ee5c ti\u00eau. Tia n\u00e0y l\u00e0 \u201ctia ph\u00e2n gi\u1ea3i\u201d, n\u00f3 qu\u00e9t t\u1edbi qu\u00e9t lui 525 \u0111\u01b0\u1eddng ngang d\u1ecdc tr\u00ean t\u1ea5m m\u1ee5c ti\u00eau v\u1edbi t\u1ed1c \u0111\u1ed9 30 l\u1ea7n\/gi\u00e2y. Nh\u1eefng tia d\u1ed9i l\u1ea1i b\u1ecb thay \u0111\u1ed5i m\u00e0 h\u00f3a ra m\u1ea1nh hay y\u1ebfu t\u00f9y theo n\u00f3 \u0111\u1ee5ng v\u00e0o \u0111i\u1ec3m t\u1ed1i hay \u0111i\u1ec3m s\u00e1ng c\u1ee7a h\u00ecnh \u1ea3nh tr\u00ean t\u1ea5m m\u1ee5c ti\u00eau.<\/p>\n\n\n\n
Giai \u0111o\u1ea1n 3: nh\u1eefng tia b\u1ecb d\u1ed9i l\u1ea1i t\u1ea1o n\u00ean nh\u1eefng xung \u0111\u1ed9ng \u0111i\u1ec7n \u0111\u01b0\u1ee3c \u0111\u01b0a v\u00e0o b\u1ed9 ph\u1eadn khu\u1ebfch \u0111\u1ea1i, sau \u0111\u00f3 \u0111\u01b0\u1ee3c chuy\u1ec3n qua tr\u1ee5 ph\u00e1t h\u00ecnh v\u00e0 t\u1eeb \u0111\u00f3 truy\u1ec1n \u0111i.<\/p>\n\n\n\n
Giai \u0111o\u1ea1n 4: qua c\u00e1c \u0103ng-ten, m\u00e1y thu h\u00ecnh thu nh\u1eefng xung \u0111\u1ed9ng \u0111i\u1ec7n do m\u00e1y ph\u00e1t s\u00f3ng \u0111\u00e3 truy\u1ec1n \u0111i, nh\u1eefng xung \u0111\u1ed9ng \u0111i\u1ec7n thu \u0111\u01b0\u1ee3c s\u1ebd \u0111\u01b0\u1ee3c \u0111\u01b0a v\u00e0o b\u1ed9 ph\u1eadn khu\u1ebfch \u0111\u1ea1i trong m\u00e1y thu r\u1ed3i \u0111\u01b0\u1ee3c chuy\u1ec3n qua \u201cs\u00fang \u0111i\u1ec7n t\u1eed\u201d trong \u1ed1ng c\u1ee7a m\u00e1y thu.<\/p>\n\n\n\n
Giai \u0111o\u1ea1n 5: kh\u1ea9u s\u00fang n\u00e0y c\u0169ng ph\u00f3ng ra nh\u1eefng tia t\u1edbi lui tr\u00ean m\u00e0n h\u00ecnh, c\u0169ng c\u00f3 525 \u0111\u01b0\u1eddng ngang v\u00e0 c\u00e1c tia n\u00e0y c\u0169ng ph\u00e2n gi\u1ea3i \u201ct\u1eebng \u0111\u01b0\u1eddng trong 525 \u0111\u01b0\u1eddng\u201d c\u0169ng v\u1edbi t\u1ed1c \u0111\u1ed9 30 l\u1ea7n\/gi\u00e2y\u201d. M\u00e0n h\u00ecnh \u0111\u01b0\u1ee3c ph\u1ee7 m\u1ed9t l\u1edbp ph\u1ed1t pho c\u00f3 kh\u1ea3 n\u0103ng s\u00e1ng l\u00ean khi n\u00f3 b\u1ecb tia l\u1eeda \u0111i\u1ec7n ch\u1ea1m v\u00e0o. V\u1eady l\u00e0 ch\u1ed7 n\u00e0o tia l\u1eeda \u0111i\u1ec7n kh\u00f4ng c\u00f3 th\u00ec m\u00e0n h\u00ecnh b\u1ecb \u0111en, ch\u1ed7 n\u00e0o tia l\u1eeda \u0111i\u1ec7n y\u1ebfu th\u00ec m\u00e0n h\u00ecnh \u201cm\u1edd\u201d, ch\u1ed7 n\u00e0o tia l\u1eeda \u0111i\u1ec7n m\u1ea1nh th\u00ec s\u00e1ng l\u00ean m\u1ea1nh. V\u00e0 nh\u01b0 v\u1eady h\u00ecnh t\u1eeb m\u00e1y ph\u00e1t truy\u1ec1n \u0111i b\u1eb1ng xung \u0111\u1ed9ng \u0111i\u1ec7n \u0111\u00e3 hi\u1ec7n nguy\u00ean si \u1edf m\u00e1y thu.<\/p>\n\n\n\n
V\u1ec1 c\u01a1 b\u1ea3n v\u1eadn h\u00e0nh c\u1ee7a m\u00e1y truy\u1ec1n h\u00ecnh v\u00e0 thu h\u00ecnh l\u00e0 nh\u01b0 th\u1ebf. M\u00e1y ph\u00e1t v\u00e0 thu h\u00ecnh m\u00e0u t\u1ea5t nhi\u00ean l\u00e0 ph\u1ee9c t\u1ea1p h\u01a1n nh\u01b0ng c\u0169ng kh\u00f4ng ngo\u00e0i nguy\u00ean t\u1eafc ph\u00e1t v\u00e0 thu c\u00e1c xung \u0111\u1ed9ng \u0111i\u1ec7n.<\/p>\n","protected":false},"excerpt":{"rendered":"
T\u1eeb kh\u00f3a t\u00ecm ki\u1ebfm: H\u00e3y Tr\u1ea3 L\u1eddi Em T\u1ea1i Sao? \u2013 T\u1eadp 5 – Arkady Leokum Tivi l\u00e0 ch\u1eef vi\u1ebft t\u1eaft c\u1ee7a Television c\u00f3 ngh\u0129a l\u00e0 \u201cnh\u00ecn c\u00e1ch kh\u00f4ng\u201d. Truy\u1ec1n h\u00ecnh tr\u1ef1c ti\u1ebfp l\u00e0 truy\u1ec1n \u0111i h\u00ecnh \u1ea3nh nh\u1eefng g\u00ec \u0111ang di\u1ec5n ra v\u00e0 ng\u01b0\u1eddi \u1edf xa c\u0169ng nh\u00ecn th\u1ea5y ngay c\u00f9ng m\u1ed9t l\u00fac, ho\u1eb7c […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":"","_disable_autopaging":false},"categories":[15],"tags":[],"class_list":["post-14602","post","type-post","status-publish","format-standard","hentry","category-hoi-dap-khoa-hoc"],"_links":{"self":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts\/14602","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/comments?post=14602"}],"version-history":[{"count":1,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts\/14602\/revisions"}],"predecessor-version":[{"id":14603,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts\/14602\/revisions\/14603"}],"wp:attachment":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/media?parent=14602"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/categories?post=14602"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/tags?post=14602"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}