dooradarshi

nyootaneeya dooradarshi ka aarekh

dooradarshi vah prakaasheeya upakaran hai jiska prayog door sthit vastuon ko dekhnane ke liye kiya jaata hai. dooradarshi se saamaanyat: log prakaasheeya dooradarshi ka arth grahan karte hain, parantu dooradarshi vidyutachunbakeeya varnakram ke anya bhaagon mai bhi kaam karta hai jaise X-re dooradarshi jo ki X-re ke prati samvedansheel hota hai, radio dooradarshi jo ki adhik tarangadairghya ki vidyut chunbakeeya tarange grahan karta hai.

dooradarshi saadhaaranataya us prakaasheeya tantr (optical system) ko kehte hain jisse dekhne par door ki vastueain bade aakaar ki aur spasht dikhaai deti hain, athva jiski sahaayata se dooravarti vastuon ke saadhaaran aur varnakramachitr (spectrograms) praapt kiye jaate hain. dooravarti vastuon ka gyaan praapt karne ke liye aajkal radio tarangon ka bhi upayog kiya jaane laga hai. is prakaar ka yantr radio dooradarshi (radio telescope) kahalaata hai. bolachaal ki bhaasha mein dooradarshi ko doorabeen bhi kehte hain.

doorabeen ke aavishkaar ne manushya ki seemit drushti ko atyadhik vistrut bana diya hai. jyotirvid ke liye dooradarshi ki upalabdhi andhe vyakti ko mili aaainkhon ke sadrush varadaan siddh hui hai. iski sahaayata se usane vishv ke un rahasyamaya jyotishpindon tak ka saakshaatkaar kiya hai jinhein ham sarpil neehaarikaaeain (spiral nebulae) kehte hain. ye neehaarikaaeain hamse karodon prakaashavarsh ki doori par hain. aadhunik jyotirvijnyaaan (astronomy) aur taaraabhautiki (astrophysics) ke vikaas mein dooradarshi ka mahatvapoorn yog hai. dooradarshi ne ek or jahaaain manushya ki drushti ko vistrut banaaya hai, vahaaain doosari or usane maanav ko un bhautik tathyon aur niyamon ko samajhne mein sahaayata bhi di hai jo bhautik vishv ke gatyaatmak santulan (dynamic equilibirium) ke aadhaar hain.

anukram

itihaas

molinyooks (Molyneux) ne apni pustak 'dioptrika nova' (Dioptrica Nova) mein likha hai ki Roger bekan (Roger Bacon) ko, jiski mrutyu san 1295 mein hui thi, doorabeen aur khurdabeen ka saiddhaantik gyaan tha, lekin dooradarshi ka sarvapratham nirmaan san 1608 ke lagbhag haulaind nivaasi hainsaliprashe (Hanslippershey) naamak vyakti ne kiya. iske baad kramash: gaililio, kepalar, haaigeinj, braidale, gregari aur nyootan aadi ne dooradarshi ka vyavasthit yantr ke roop mein vikaas kiya. doorabeen ke vikaas mein gaililio ka mahatvapoorn yog hai. gaililio ne apne dooradarshi ki sahaayata se sansaar ko yeh bata diya hai ki koparniks ki sooryakeindreeya (heliocentric) jyotirvyavastha satya hai aur taalimi ki bhookeindreeya (geocentric) vyavastha ashuddh hai.

prakaar

chitr:Newtonian Telescopes.JPG
nyutoniyn dooradarshi (yon) ka samuh Perkins vedhashaala, Delaware, ohaayo par
  • (1) apavartan dooradarshi (refracting telescope) tatha
  • (2) paraavarti dooradarshi (reflecting telescope).
  • X-re dooradarshi

kuchh prasiddh dooradarshi

dooradarshi se yukt ek Hecate .338 rifle
shikaar karne ke liye prayukt hathiyaaron par lagne vaale dooradarshi ki kriya-vidhi

kuchh vishvavikhyaat dooradarshiyon ka vivran nimnalikhit hai :

yarakij (Yerkes) dooradarshi

yeh sansaar ka sabse bada apavartan dooradarshi tha. iske abhidrushyak leins ka vyaas 40 inch hai. amareeka ki yarakij vedhashaala mein san 1897 mein iska aarohan hua tha.

mount vilsan ka dooradarshi

is dooradarshi ka aarohan san 1919 mein amareeka ki mount vilsan vedhashaala mein kiya gaya tha. is dooradarshi ke paraavartak ka vyaas 100 inch hai. iski sahaayata se hamaari aakaashaganga (galaxy) se pruthak rahanevaale aakaasheeya pindon ka nireekshan sambhav ho saka hai. is dooradarshi ke paraavartak ka bhaar tan ke lagbhag hai tath iski gati sambandhi vyavastha ka bhaar 100 tan hai. jis gunbanj mein iska aarohan hua hai unka vyaas 100 foot aur ooainchaai 105 foot hai.

hel paraavartak dooradarshi

dau॰ elari hel (Ellery Hale) ke prayatnon ke parinaamasvaroop amareeka mein pailomaur (Palomar) vedhashaala ki sthaapana ki gayi. san 1947 mein is vedhashaala mein 200 inch vyaas ke paraavartak ka aarohan hua. dau॰ hel ke naam par is dooradarshi ka naam hel dooradarshi rakha gaya. yadyapi is dooradarshi ka sampoorn bhaar 530 tan hai, tathaapi iska santulan itni uttam vidhi se kiya gaya hai ki keval ashvashakti ki motor dvaara ise bhali bhaaainti ghumaaya ja sakta hai. is dooradarshi ka paraas (range) do arab lakh prakaashavarsh hai.

radio dooradarshi

prakaasheeya dooradarshi mein prakaash ke dvaara hamein aakaashasth pindon ke vishay mein soochana praapt hoti hai. radio dooradarshi mein prakaasheeya pindon dvaara utsarjit radio tarangon ke dvaara unki rachana ityaadi ke sambandh mein jaankaari praapt ki jaati hai. san 1931 mein jaanski dwaar yeh ghoshana ki gayi ki aakaashaganga ya uske paas ke pradeshon se radio tarangein pruthvi par aati hai aur in tarangon se un pradeshon ke sambandh mein jaankaari praapt ki ja sakti hai. radio dooradarshi ka aadhaar jaanski (Jansky) ka ukt anveshn hai.