應用光電
Homework 1
97 年度第二學期
碩研光電一甲
1. (P9.10*) White light falling on two long narrow slits emerges and is
observed on a distant screen. If red light (0 = 780 nm) in the first-order
fringe overlaps violet in the second-order fringe, what is the latter’s
wavelength?.
2. (P9.26) A soap film surrounded by air has an index of refraction of
1.34. If a region of the film appears bright red (0 = 633 nm) in normally
reflected light, what is its minimum thickness there?
Sol:
.
d
air
Soap film
3. 對於雙狹縫干涉實驗，請說明為何入射光波長不同，屏障上亮線
的位置也不同？
4. Assume mean wavelength and linewidth of an LED (red) are 650 nm
and 30 nm, respectively. Calculate its coherence length.
5. 為什麼時間相干性最好的光源為單頻的光源？
6. 說明 Fraunhofer diffraction 與 Fourier Transform 的關係。.
7. 為何平面波入射至一光學元件時，出射光可視為許多前進方向不
同的平面波的組合?