Announcements 3/30/11 Prayer Exam 3 review session: Thursday, 5-6:30

pm. Location: room C258 ESC Exam 3 starts Saturday, goes through next

Saturday. Exam not written yet… on Friday I’ll be able

to give you some details. If you used the Tutorial Lab, please rate

the TAs: http://gardner.byu.edu/tas/tutorrating.html (rating form has photos)

Reading quiz

Which of the following is NOT true of the 3D “wave vector”?

a. Its magnitude is equal to 2/.b. In a plane wave it points in the same

direction everywhere in space.c. In a spherical wave it points in the

same direction everywhere in space.d. It tells us which way the wave is

going.e. In 1D it reduces to the wave number

k.

Waves in 3-dimensions

Plane wavesa. polarization

Wave vectora. direction of wave

Spherical waves

Student-designed problem: Transverse Wave

What direction do you want the wave to be traveling in?

What direction do you want the wave to be oscillating in?

What wavelength do you want the wave to have?

What do you want the wave’s amplitude to be?

What frequency (or velocity) do you want the wave to have?

What do you want the overall phase of the wave to be?

Lasers

What makes a laser special? (answers from class)

Some of my answers:a. Single wavelengthb. Intensec. Collimatedd. Coherence (spatial,

temporal) - 99.9999999999%

Actual laser spectrum is over 100

narrower than the width of the red line

Blackbody spectrum

Laser spectrum

Lasers

Principal components:1. Gain medium2. Laser pumping energy3. High reflector4. Output coupler5. Laser beam

Energy (light,

electrical, etc.)

AbsorptionEmission

light

Stimulated Emission

Image & list from Wikipedia

Energy (light)

More Wikipedia

Green laser pointer

1. gain medium(Nd:YVO4 crystal)

2. laser pumping energy (808 nm LED beam)

3. high reflector

4. output coupler

5. laser beam

More Wikipedia

Circular Polarization

Pictures from Wikipedia

Remember these pictures?

Optical Retarders, aka “Wave plates”

Quartz, SiO2: no = 1.544, ne = 1.553

Calcite, CaCO3: no = 1.658, ne = 1.486

Pictures from Wikipedia

Calcite crystal:

Optical Modulators

Electro-optic modulator Acousto-optic modulator

AOM

EOM

www.newport.com wikipedia

Field changes vertical index of

refraction