第二章测试1.What type of laser does the carbon dioxide laser belong to?（ ）
A:Solid-state laser B:Semiconductor laser C:Gas laser D:Fiber laser
答案:C
2.When the pulse energy is certain, the narrower the pulse width, it means the time energy density with time as the denominator （ ）.
A:the smaller B:The greater C:Constant D:Uncertain
答案:B
3.For a uniformly broadened medium, the small-signal gain coefficient at the center center frequency is G0(v0), and when I=Is, saturation is significant, and the non-small-signal center-frequency gain coefficient is: （ ）.
A:
B: 
C: 
D: 
答案:B
4.The following statement about the electric field induction formula is correct （ ）。
A:ε (z,x,y,t ) is dielectric permittivity B:P (z,x,y,t ) is polarization of a medium C:all D:E (z,x,y,t ) is electric field strength
答案:C
5.What is the Duffing’s equation used to calculate electron displacement? （ ）
A:
B:
C:
D:
答案:D
6.The threshold condition is the formation of laser（ ）。
A:necessary condition. B:sufficient necessary condition. C:Indeterminate. D:sufficient condition.
答案:B
7.When a laser propagates from one medium to another with a different refractive index, a (C) will appear at the interface between the media（ ）。
A:Refraction B:Neither C:Reflections D:Reflection and refraction
答案:D
8.The collisional broadening spectral line is（ ）。
A:Gaussian line type B:Parabolic type C:Hyperbolic type D:Lorentzian linear
答案:D
9.Particle number reversal distribution state microscopic particles satisfy （ ）
A:Bormanz distribution B:Gaussian distribution C:Negative temperature distribution D:Fermi distribution
答案:C
10.At a certain temperature, the odds of spontaneous radiation are （ ） times greater than the odds of excited radiation
A:
B:
C:
D:
答案:B
