Quiz 3 (Optical Spectroscopy)

Question 1

Continuous sources

Answer 1

wide range of wavelengths in a continuum output

Question 2

Line sources

Answer 2

emit light @ a specific wavelength

Question 3

Lasers require?

Answer 3

1) laser cavity
2) lasing medium
3) pumping mechanism
4) optics

Question 4

Laser cavity

Answer 4

contains lasing medium

Question 5

Lasing medium

Answer 5

material that contains somewhat stable excited state

Question 6

Pumping mechanism

Answer 6

electrical discharge to sustain population inversion

Question 7

Optics

Answer 7

mirrors on either end of laser cavity
1) fully reflective
2) partially reflective

Question 8

Lasing mechanism

Answer 8

1) flash lamp builds up population inversion
2) fluorescence occurs
3) some photons pass back through laser cavity via reflection to interact w/ lasing medium

Question 9

For constructive interference to continue….

Answer 9

1) maintain population inversion
2) ensure cavity length

Question 10

Optical filters

Answer 10

block certain wave length ranges & allow others to pass

Question 11

Monochromators

Answer 11

allow only a single wavelength to pass through

Question 12

Monochromator components

Answer 12

1) entrance & exit slits
2) dispersive device (prism)
3) optics (lenses, mirrors)

Question 13

Prism concepts

Answer 13

refraction
dispersion

Question 14

Prism wavelength

Answer 14

shorter wavelengths are dispersed to a greater degree than larger wavelengths

Question 15

Diffraction grating concepts

Answer 15

diffraction
reflection

Question 16

Fastie-Elbert

Answer 16

• entrance & exit slits placed symmetrically placed on opposite sides of grating
• spherical mirror

Question 17

Littrow

Answer 17

• entrance & exit slits next to each other
• collimating mirror
• rays of light travel parallel

Question 18

Czerny-Turner

Answer 18

• 2 focusing mirrors
• entrance & exit slits next to each other pointing to regular mirrors