6D20.15 Diffraction Grating
A laser pointer shining on a diffraction grating or CD creates a series of diffraction spots depending on the spacing of the lines or pits in the grating or CD and the wavelength emitted by the laser.
-  Red laser pointer
-  Green laser pointer
-  Diffraction grating
-  CD
- Make sure you have a clear space to shine a laser without striking anyone in the eye, either with direct, diffracted, or reflected beams.
- Lasers can cause blindness. Use with caution.
- Shine the green laser through the diffraction grating so that the diffracted beams are visible on a screen or wall.
- Remark on how the spacing of grating lines affects the diffracted dot spacing.
- Do the same with the red laser for comparison.
- While holding the CD, make a remark about the scourge of AOL CDs in the 90s.
- Reflect the green and red lasers off the CD's surface to get similar diffraction patterns for the CD.
- Remark on how the CD has a pattern of pits and grooves that also diffracts light like a grating.
- PIRA 6D20.15, 6D20.32
- Don't attempt this at home!
If you have any questions about the demos or notes you would like to add to this page, contact Ricky Chu at ricky_chu AT sfu DOT ca.