Home / Ilm / AYNAK

AYNAK

aynakAYNAK, asbobi optikist baroi islohi nuqsi bosira yo muhofizati chashm. On az shisha (linza) va chanbarak iborat ast. Tavassuti chanbarak shishahoi A. nisbat ba sathi chashm durust joygir meshavand va kamonaku vositahoi dig. A.-ro dar holati muayyan nigoh medorand. CHand kheli A. mavjud ast: agar yake nuqsi optikii chashmro isloh kunad, digare chashmro az osebu rushnoii tez emin medorad. Aynaki musleh (islohkunanda). Dar muhiti yakkhelai musaffo nuri rushnoi mustaqim pahn megardad. Hangomi az yak muhit ba muhiti digar guzashtan, nur samti khudro tagiyr medihad, yane on meshikanad. Kori shishahoi optiki yo linzaho dar zaminai hamin khususiyati dar muhiti harkhela pahn shudani rushnoi asos yoftaast. Nurhoi muvozii rushnoi az linzai du tarafash barjasta meguzarand va minbad dar yak nuqtai pasi linza, yane dar fokus, jam meshavand. Onro shishai jamkunanda yo musbat menomand va bo alomati plyus (+) ifoda menamoyand. Nurhoi muvozii rushnoi hangomi az linzai du tarafash furukhamida guzashtan, dar peshi linza fokusi durugin paydo khohand kard. SHishai du tarafash furukhamidaro linzai pahnkunanda (manfi) menomand va bo alo- mati minus (-) ifoda mekunand. Gayr az shishahoi mudavvari nomburda linzahoi ustuvonashakle hastand, ki shuoro jam yo pahn mesozand. Masofai bayni fokus va markazi shishai optikiro masofai fokusi menomand. Masofai fokusi har qadar kam boshad, quvvai inkisorii on hamon qadar ziyod meshavad. Vohidi quvvai shishahoi optiki dioptriya ast. SHishahoi masofai fokusiashon ba 1m barobar 1 dioptriya quvva dorand. Baroi muayyan kardani quvvai optikii har yak shisha 1 metrro ba masofai fokusii hamon shisha taqsim mekunand. Mas., agar masofai fokusi 2 m boshad, kuvvai optikii linza barobari 0,5 dioptriya (1 : 2 m) va agar masofai fokusi 0,5 m boshad, quvvai optikii linza barobari 2 dioptriya (1 : 0,5 m), 0,25 m – 4 dioptriya, 0,1 m – 10 dioptriya meshavad va g. A.-hoe, ki az shishahoi jamkunanda tahiya shudaand, hangomi durbini va baroi piron (nig. Durbinii pirona) zarur meboshand, chunki onho norasoii tatobuqro jubron mekunand (nig.CHashm). Quvvai optikii shishai chunin A.-ho bo dioptriya chen karda meshavad va onho alomati «+» dorand. A.-hoi shishahoyashon pahnkunanda baroi nazdikbini lozimand; quvvai optikii onho bo dioptriya chen karda shuda, bo alo- mati «-» ifoda meyobad. Dar holati astig- matizm bosirai zaif bo yorii A.-hoe, ki az shishahoi silindri yo chanbarshakl tayyor shudaand, behtar karda meshavad. Bazan baroi ham dur va ham nazdikro didan, A.-i bifokali (dufokusa), yane A.-i shishaash duhisaro istifoda mebarand. Tavvasuti qismi boloii in guna linzaho ma- sofai dur va bo qismi poyoniash masofai nazdikro didan mumkin ast. Baroi kori harruza A.-e, ki durust intikhob shudaast, khele muvofiq meboshad. Bazeho ba A. zud odat namekunand. Beshtar, in holat dar asnoi avvalin bor istifoda burdani A. ruy medihad. To ba A. khu giriftan, achab nest, ki har guna firebi nazar (khurd yo kalon ba nazar rasidani ashyo, harakati onho barobari gardishi chashmu sar, nazdik yo dur vonamud shudani sathi zamin va g.) padid oyad. Dar naticha sar charkh zada, dil behuzur megardad. Alomathoi mazkur bad az 2 – 3 hafta khud az khud nest meshavand. Agar dar in muddat odam ba A. odat nakunad, on goh hatman mashvarati dukhtur lozim ast. Dar mavridi illati budani qarniyai chashm, yo khud dar yake az chashmho nabudani zuchochiya va yo farqi kalon doshtani quvvai optikii chashmho A. manfiat namerasonad. Dar in surat az linzahoi tamosi (kontakti), ki bevosita ba qismi peshi guzai chashm guzoshta shuda, hamrohi chashm sistemai optikii umumiro tashkil medihand, istifoda menamoyand. Linzahoi tamosi qobiliyati kori yakchoyai har du chashmro nisbat ba A.- hoi oddi behtar barqaror mekunand. In makhsusan baroi odamone, ki dar faoliyati mehnatiashon chashmi khub doshtan va durust muayyan kardani masofa talab karda meshavad, khele zarur ast. Linzahoi tamosi nisbat ba linzahoi muqarrari az chihati kosmetiki niz bartari dorand (ba atrofiyon nonamoyonand). Linzahoi tamosiro az navhoi makhsusi plastmassa (qutrashon 8 – 9 mm) tayyor mekunand; onhoro 4 – 6 soat istifoda burdan mumkin ast. A.-hoi teleskopi az qabili aynakhoi makhsusand. Onho ba durbin monand buda, az du linza (chamkunanda va pahnkunanda) iboratand, ki dar yak chanbaraki umumi nasb shudaand. In guna A.-ho quvvai bosiraro taqriban du marotiba ziyod karda, dar mavridi az osebi shabakai chashm yo asabi bosira yakbora zaf yoftani tezii binish metavonand kumak rasonand. Dar asnoi khosta giriftani A. chanbaraki onro bo diqqati tamom intikhob kardan lozim ast. CHanbarakro behtarash mutakhassisi hamin soha intikhob namoyad. CHanbarak naboyad bini va gushro ozor dihad. On boyad dar peshi chashm mavqei durusti linzaro tamin namoyad (yane ba masofai gavharaki chashm muvofiq boshad). Imruzho A.-ro ba bachagon nisbat ba soliyoni pesh beshtar tavsiya mekunand. In az yak taraf ba on vobasta ast, ki bosirai kudakon khele barmahal tadqiq va nuqsoni chashm sari vaqt oshkor karda meshavad. Az tarafi digar, chashmro az had ziyod khasta kunondan (khususan khondan va tamoshoi televizor, bozi bo kompyuter) beshtar boisi inkishofi nazdikbini dar maktabbachagon va hatto kudakoni khurdsol megardad. Ba kudakon tain namudani A. masuliyati khele chiddist. A.-e, ki nodurust intikhob shudaast, nafaqat bosiraro behtar namesozad, balki ba on ziyon niz merasonad. Kudakone, ki dar chashm A. megirand boyad sole yak marotiba az muoinai dukhturi okulist guzarand. A.-i muhofizro bo maslihati dukhturi chashm khosta giriftan zarur ast. Boyad on surokh nadoshta boshad to in ki chismhoi begona ba chashm naaf- tand. Pas az anchomi kor A.-ro bo lattai toza pok karda, ba daruni qutticha yo gilofi makhsus mondan lozim ast.

Загрузка...

Dar boramon

Инчунин кобед

litosfera

SOHTORI LITOSFERA

Dar paragrafi peshina mo qayd kardem, ki litosfera (az kalimai yunonii lithos – sang va …