Color and Polarization

1. Color and Polarization

2. Objectives • Recognize how additive colors affect the color of light. • Recognize how pigments affect the color of reflected light. • Explain how linearly polarized light is formed and detected.

3. Color • Color is all around us. • Color is due to light absorbing and reflecting properties. • Objects either absorb or reflect light.

4. Primary Colors • Red, Blue and Green • Rods vs. Cones

5. Experiment • Take a piece of paper. • Color red dot. • Stare at it for 30 seconds, flip it over. • What do you see?

6. Complementary Colors • Colors you add together to get white. • Blue + yellow= white light. • Yellow is red + green so blue + yellow + green.

7. Subtractive Pigments • When you mix blue and yellow colors you get green. • Yellow reflects-absorbs blue and violet. • Blue-absorbs red, orange and yellow. • Both reflect Green.

8. Review • What is the difference between light reflection and pigments? • How do you obtain different colors? • How do we create different colors?

9. Polarization • Polarized vs Unpolarized light. • Unpolarized light- electromagnetic waves are in various directions. • Polarized light- electromagnetic waves vibrate parallel to one another.

10. Polarizing Light • Certain crystals polarize light as it passes through them. • Which way it is polarized is determined by the direction of the crystals.

11. Transmission Axis • Only light waves that are linear with transmission axis pass through. • All other light will not pass through. • Makes the light dimmer.

12. Using Multiple Polarizers • The closer to being lined up the light will pass the same through up to being perpendicular where no light passes through.

13. Review • Page 478. P. 39,43,44,45 • Quiz Tomorrow.