Re: [題目] 光學題目
※ 引述《melvyn (Aeneas)》之銘言：
: [領域] 光學
: [來源] 課本習題(Pedrotti, Introduction to optics 3rd Ed.
: Pearson Education, 2007)
: [題目]Q1. The separatopm pf a certain doublet 0.0055 nm at a wavelength of
: 490 nm. A variable-spaced Fabry-Perot interferometer is used to
: examine the doublet. At what spacing does the (m)th order of one
: component coincide with the (m+1)th order of the other.
: The ans of Q1 is 2.18 cm
: Q2. White light is passed through a Fabry-Perot interferometer in the
: arrangement shown in Figure,where the detector is a spectroscope.
: A series of bright bands appear.When mercury light is simultaneously
: admitted intto the spectroscope slit,150 of the bright bands are
: seen to fall between the violet and green lines of mercury at
: 435.8 nm and 546.1 nm,respectively.What is the thickness of the
: etalon?
: Figure:http://0rz.tw/b04d4
: The ans of Q2 is 0.161 mm
: [瓶頸]
: 這兩題我都利用 d = mλ/2 ,可是都與課本給的答案不符
: 想請問錯再哪？
L = mλ/2
=> λ = 2L/m
=> dλ/dm = -2L/(m^2)
=> Δλ≒ (2L/(m^2))*Δm or 將 m = 2L/λ代入可得
=> Δλ= ((λ^2)/2L)*Δm
=> 2L = ((λ^2)/Δλ)*Δm
For Q1:
Δλ= 0.0055nm ， λ= 490nm 且 Δm = 1
=> Ans: 2.18 cm
For Q2:
Δλ= 546.1nm-435.8nm = 110.3nm ， Δm = 150
且 λ≒ (546.1nm+435.8nm)/2 = 490.95nm
=> Ans: 0.164 mm (誤差有點大)
我想大概是這樣吧
有錯請指教
--
※ 發信站: 批踢踢實業坊(ptt.cc)
◆ From: 140.113.94.97
※ 編輯: jack6353 來自: 140.113.94.97 (05/29 23:33)
討論串 (同標題文章)
本文引述了以下文章的的內容：
完整討論串 (本文為第 2 之 2 篇)：