CD na gani ya zama a bainar jama'a a 1982, samfurin ya fito ko da a baya - a cikin 1979. Da farko, an ƙirƙira CDs a matsayin maye gurbin fayafai na vinyl, a matsayin mafi inganci kuma mafi amintaccen kafofin watsa labarai. An yi imanin cewa fayafai na Laser shine sakamakon aikin haɗin gwiwa tsakanin ƙungiyoyin kamfanoni na fasaha guda biyu - Sony na Japan da Philips Dutch.
A lokaci guda, fasaha na asali na "laser na sanyi", wanda ya sa bayyanar diski na laser ya yiwu, masana kimiyyar Soviet sun haɓaka. и . An ba su lambar yabo ta Nobel don ƙirƙira da suka yi. Fasahar ta kara bunkasa, kuma a cikin 70s Philips ya kirkiro hanyar yin rikodin ƙananan fayafai, wanda ke nuna farkon CD ɗin. Da farko, injiniyoyin kamfanin sun ƙirƙiri ALP (wasa mai tsawo) a matsayin madadin bayanan vinyl.
Diamita na fayafai ALP ya kai kusan santimita 30. Bayan ɗan lokaci, injiniyoyi sun rage diamita na fayafai, kuma an rage lokacin wasan zuwa awa 1. Fayafai Laser da na'urar sake kunnawa gare su sune farkon Philips a shekarar 1979. Bayan haka, kamfanin ya fara neman abokin tarayya don ƙarin aiki a kan aikin - masu haɓaka suna ganin fasahar a matsayin kasa da kasa, kuma yana da wuya a bunkasa ta zuwa matakin da ake bukata da kuma yada shi da kansu.
Farkon komai
Hukumar gudanarwar ta yanke shawarar kokarin kulla hulda da kamfanonin fasaha daga kasar Japan, a wancan lokacin wannan kasar ta kasance a sahun gaba a fasahar hi-end. Don yin wannan, wakilan Philips sun je ƙasar kuma sun sami damar ganawa da shugaban Sony, wanda ya zama mai sha'awar fasahar.
Kusan nan take akwai ƙungiyar injiniyoyin Philips-Sony, sun haɓaka ƙayyadaddun bayanai na farko na fasaha. Mataimakin shugaban kamfanin Sony ya dage kan kara girman fayafai; yana son karamin ya sami damar daukar nauyin wasan kwaikwayo na Beethoven na tara, wanda aka fadada girman diski daga sa'a 1 zuwa mintuna 74 (akwai kuma ra'ayi cewa wannan shine kawai. kyakkyawan labarin talla). Adadin bayanan da suka dace akan irin wannan faifai shine 640 MB. Injiniyoyi kuma sun ƙirƙira sigogin ingancin sauti. Misali, mitar siginar sitiriyo an daidaita shi a 44,1 kHz (na tashar 22,05 kHz ɗaya) tare da ɗan faɗin bits 16 kowanne. Wannan shine yadda ma'aunin Red Book ya bayyana.
Sunan sabuwar fasaha bai bayyana ba zato ba tsammani - an zaɓi shi daga zaɓuɓɓuka da yawa, ciki har da Minirack, Mini Disc, Compact Rack. A sakamakon haka, masu haɓakawa sun haɗu da lakabi biyu, wanda ya haifar da haɗakarwa mai haɗakarwa. Ba ko kaɗan ba, an zaɓi wannan sunan ne saboda haɓakar kaset ɗin sauti (fasaha ).
Philips da Sony kuma sun taka muhimmiyar rawa wajen haɓaka ƙayyadaddun ƙayyadaddun ƙayyadaddun fayafai na dijital na farko, wanda ake kira Littafin Yellow ko CD-ROM. Sabuwar ƙayyadaddun ƙayyadaddun bayanai ya ba da damar adana ba kawai sauti ba, har ma da rubutu da bayanan hoto akan fayafai. An ƙayyade nau'in diski ta atomatik lokacin karanta rubutun. Matsalar ita ce CD mai dacewa da littafin Yellow Book zai iya aiki da wani nau'in tuƙi kawai, wanda ba na duniya bane.
A ranar 17 ga Agusta, 1982, an fitar da CD na farko a masana'antar Philips a Langenhagen, Jamus. An yi rikodin kundin a kansa ABBA group. Ya kamata a lura da cewa murfin varnish na fayafai na farko ba su da inganci sosai, don haka masu siyar da ƙamshi sukan lalata su. Bayan lokaci, ingancin fayafai ya inganta. A cikin 'yan shekarun farko an yi amfani da su na musamman a cikin kayan aikin hi-fi, an yi amfani da su azaman maye gurbin rikodin vinyl da kaset.
Tun 2000, 700 MB fayafai sun fara bayyana akan siyarwa, wanda ya ba da damar yin rikodin sauti tare da jimlar har zuwa mintuna 80. Gaba daya suka kori motoci 650 daga kasuwa. Akwai kuma 800 MB na kafofin watsa labarai, amma ba su dace da duk faifai ba, don haka irin waɗannan faifai ba su da yawa musamman. Ya yiwu a ƙara yawan sararin samaniya don ajiyar bayanai ta hanyar rage nisa tsakanin waƙoƙi. Don haka, alal misali, faifai 650 MB nisa tsakanin waƙoƙi shine 1,7 microns, kuma ga faifai 800 MB wannan adadi ya ragu zuwa microns 1,5. Har ila yau, ga tsohon, gudun shine 1,41 m / s, kuma na ƙarshe, 1,39 m / s.
Ta yaya wannan aikin
Faifan ya ƙunshi yadudduka da yawa. Substrate shine polycarbonate, kauri shine 1,2 mm, diamita shine 120 mm. An sanya wani Layer a kan substrate - karfe (zai iya zama zinariya, azurfa ko, mafi sau da yawa, aluminum). Bayan haka, ana kiyaye shingen ƙarfe tare da varnish, wanda aka yi amfani da zane-zane. Ƙarfe mai dogaro da aminci yana ba da kariya ga Layer na ƙarfe, don haka zurfafa zurfafawa suna tsoma baki tare da karatu. Diamita na rami a cikin faifai shine 15 mm.
Tsarin adana bayanai don faifai - (an tattauna a sama). Ana gyara kurakuran karatu ta amfani da lambar Reed-Solomon, ta yadda zazzagewar haske kada ya rage iya karanta diski.
Ana rubuta bayanai zuwa faifai a cikin nau'in waƙar karkace na abin da ake kira ramuka (ramuka), waɗanda aka fitar da su cikin tushen polycarbonate. Zurfin kowane rami yana da kusan 100 nm kuma faɗinsa shine 500 nm. Tsawon rami daga 850 nm zuwa 3,5 µm. Ramin yana watsewa ko ɗaukar haske, ƙirar tana nunawa. Don haka, faifan da aka yi rikodi shine kyakkyawan misali na ƙwanƙwasa ƙwanƙwasa.
Ana karanta fayafai ta hanyar amfani da katako mai laser tare da tsayin daka na 780 nm, wanda laser semiconductor ke fitarwa. Ka'idar karatun ita ce yin rajistar canje-canje a cikin ƙarfin haske mai haske. Don haka, katako na Laser yana haɗuwa a kan bayanan bayanan, diamita na wurin haske a cikin wannan yanayin shine 1,2 microns. Ana yin rikodin sigina mafi girma tsakanin ramuka. Idan ya fada cikin rami, ana yin rikodin ƙananan ƙarfin haske. Canje-canje a cikin ƙarfin yana canzawa zuwa siginar lantarki, wanda kayan aiki ke aiki da shi.
Yadda ake ƙirƙirar diski
- Mataki na farko shine shirya bayanai don ƙaddamarwa cikin jerin;
- Photolithography shine mataki na biyu kuma shine tsarin ƙirƙirar tambarin diski. Da farko, an ƙirƙiri faifan gilashi, wanda aka yi amfani da Layer na kayan aikin hoto, kuma ana rubuta bayanai akansa. Kayan yana canza halayensa na zahiri da sinadarai a ƙarƙashin rinjayar haske;
- Ana yin rikodin bayanai ta amfani da katako na Laser. Lokacin da ƙarfin laser ya karu (lokacin da ya zama dole don ƙirƙirar rami), an lalata haɗin sinadarai na kwayoyin halitta na kayan aikin photoresist kuma yana daskarewa;
- Ana cire hoton hoto (ta hanyoyi daban-daban, daga plasma zuwa acid), an cire wuraren da laser ba ya shafa daga matrix;
- Ana sanya faifan a cikin wanka na galvanic, inda aka ajiye wani Layer na nickel a samansa;
- Ana buga fayafai ta hanyar gyare-gyaren allura, ta yin amfani da faifan gilashin asali azaman kayan tushe;
- Bayan haka, ana fesa ƙarfe a kan layin bayanai;
- Ana amfani da varnish mai karewa zuwa gefen waje, wanda aka riga an yi amfani da hoto mai hoto.
Menene CD-RW?
CD-RW wani nau'in faifan diski ne wanda aka ƙaddamar a cikin 1997. Asalin ma'aunin an kira shi (CD-E, Karamin Disc mai gogewa).
Wannan babban ci gaba ne a fagen yin rikodi da adana bayanai. Bayan haka, samun matsakaicin ajiya mara tsada kuma mai ƙarfi shine mafarkin dubban injiniyoyi da masu amfani. CD-RW yayi kama da tsari da ka'idar aiki zuwa CD na yau da kullun, amma Layer na rikodi ya bambanta - yana da allo na musamman na chalcogenides. Mafi yawan amfani shine azurfa-indium-antimony-tellurium. Lokacin da zafi sama da wurin narkewa, irin wannan gami yana canzawa daga yanayin crystalline zuwa wani amorphous.
Canjin lokaci a cikin wannan yanayin yana canzawa, wanda shine tushen tsarin sake rubutawa. A kauri daga cikin aiki Layer na faifai ne kawai 0,1 microns, don haka yana da sauki a yi tasiri da abu tare da Laser. Tsarin rikodi yana faruwa lokacin da aka fallasa shi zuwa katako na Laser; a wannan yanayin, Layer mai aiki ya juya ya zama narke (waɗannan wuraren da Laser ya shafa). Bayan haka, zafi yana yaduwa a cikin ƙasa, kuma narke ya juya zuwa yanayin amorphous. Don sassan amorphous, halaye kamar dielectric akai-akai, tunani, kuma, sabili da haka, tsananin canjin haske mai haske. Yana ɗaukar bayanai game da rikodin akan faifai. Ana yin karatu ta hanyar amfani da ƙananan laser mai ƙarfi, wanda ba zai iya rinjayar Layer mai aiki ba. A lokacin rikodi, Layer mai aiki yana zafi zuwa digiri 200 na Celsius, wanda ke ba shi damar sake jujjuya lokaci zuwa yanayin crystalline.
Yin amfani da CD-RW akai-akai yana haifar da gajiyar inji na Layer na aiki. Don haka, injiniyoyin da suka haɓaka fasahar sun yi amfani da abubuwa masu ƙarancin gajiya. CD-RW na iya jure kusan zagayowar sake rubutawa dubu.
DVD - har ma fiye da iya aiki!
DVDs sun fara bayyana a Japan a cikin 1996, a matsayin martani ga mabukaci da buƙatun kasuwanci don ƙara girman manyan kafofin watsa labarai. Da farko, kamfanoni da yawa sun ƙirƙira faifai masu ƙarfi a lokaci ɗaya. Hanyoyi guda biyu na ci gaba masu zaman kansu sun fito: Multimedia Compact Disc (Philips da Sony), - Super Disc (manyan kamfanoni 8, gami da Toshiba da Time Warner). Bayan ɗan lokaci, duka kwatance sun haɗu zuwa ɗaya ƙarƙashin rinjayar IBM. Ta shawo kan abokan haɗin gwiwar kada su sake maimaita abubuwan da suka faru na "yakin tsarin", lokacin da aka yi yaƙi don fifiko tsakanin Tsarin Gida na Bidiyo da ka'idodin kaset na bidiyo na Betamax.
An sanar da fasahar a watan Satumbar 1995, kuma masu haɓakawa sun buga ƙayyadaddun bayanai a wannan shekarar. An saki DVD burner na farko a cikin 1997.
Yana yiwuwa a ƙara ƙarfin yin rikodi yayin da ake kiyaye ma'auni iri ɗaya ta hanyar amfani da jan Laser mai tsayin 650 nm. Filin waƙa shine rabin na CD kuma shine 0,74 microns.
Blu-Ray shine mafi kyawun hanyoyin sadarwa na gani
Wani nau'in kafofin watsa labarai na gani tare da mafi girman yawan bayanai fiye da CD ko DVD. Ƙungiyar BDA ta ƙasa da ƙasa ta haɓaka mizanin. Samfurin farko ya bayyana a watan Oktoba 2000.
Fasahar ta ƙunshi amfani da Laser gajeriyar igiyar ruwa (tsawon tsayin 405 nm), saboda haka sunan. An cire "e" saboda kalmar blue ray ya zama ruwan dare a cikin Ingilishi kuma ba za a iya haƙƙin mallaka ba. Amfani da Laser blue (blue-violet) ya sa ya yiwu a rage waƙar zuwa 0,32 microns, yana ƙara yawan rikodin bayanai. An ƙara saurin karatun kafofin watsa labarai zuwa 432 Mbit/s.
UDF - Tsarin diski na Duniya
UDF ƙayyadaddun tsarin tsarin fayil ne mai zaman kansa na OS. An ƙera shi don adana fayiloli akan kafofin watsa labarai na gani - duka CD, DVD da Blu-Ray. UDF ba ta da iyaka 2GB ko 4GB don fayilolin da za a iya rubutawa, don haka ya dace don DVD masu ƙarfi da Blu-rays.
Fayafai na gani da Intanet
Kamfanonin fasaha na ci gaba da inganta fayafai na gani. Don haka, Sony da Panasonic sun sami damar haɓaka ƙarfin kafofin watsa labarai na gani zuwa 2016 TB baya a cikin 3,3. A lokaci guda, aikin diski ya kasance, a cewar wakilan Sony, har zuwa shekaru 100.
Duk da haka, kowane nau'in faifai na gani suna raguwa sannu a hankali - tare da haɓaka Intanet, buƙatar masu amfani don tara bayanai akan faifai suna ɓacewa. Ana iya adana bayanai a cikin gajimare, wanda ya fi dacewa (yadda amintacce ne wata tambaya). CD ɗin ba su yi kusan shahara kamar yadda suke a ƴan shekarun da suka gabata ba, amma da alama ba za su fuskanci cikakken mantawa ba (kamar yadda yake a cikin kaset ɗin sauti) - za a yi amfani da su don ƙirƙirar tarihin mahimman bayanan kasuwanci.
Idan terabyte optical disks ya shiga samarwa, amfani da su zai iyakance - watakila za a yi amfani da su don rarraba fina-finai na 4K da wasanni na zamani tare da kari iri-iri. Amma mafi yawansu za a yi amfani da su don ƙirƙirar madadin. Kuma idan Sony yana faɗin gaskiya game da amincin bayanan da aka yi rikodin ƙarni na ƙarni, to kasuwanci zai yi amfani da sabuwar fasahar sosai.
source: www.habr.com
