Level 1 Chapter 2 Quiz: Laser Basics 

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1. Laser light is:
wavelike
partical like
both wavelike and particle like

2. Lasing is possible when:
pumping power is on
population inversion exists

3. To get smaller possible laser focal spot size, one should:
select laser with longer wavelength
use short lens focus length
decrease the beam diameter before focusing
use shorter wavelength laser and longer focus length lens

 

4. The Depth of Focus for a laser is:
inverse proportional to the wavelength
shorter when the focal spot size is smaller
usually advantageous for laser machining when it is short

5. Which of the following atatements about laser modes is not correct?
Laser modes are the standing em waves in laser cavity
Laser modes can be divided into longitudinal mode and TEM mode
The higher the mode, the easier to focus the laser beam to a small point

 6. A laser beam is of wavelength l =0.355*10^-3 mm and diameter D=3 mm, b =1.1, what is its diffraction limited divergence?