M1-22
Demonstrate diffraction (well, actually interference) by a grating.
Several different gratings can be readily mounted into the laser beam to study the effect of grating spacing: (1) 570 slits per mm, (2) 13,400 slits per inch, and (3) a triple grating with 2400 slits per inch, 7500 slits per inch, and 15,000 slits per inch. The patterns from the three slits of the triple grating are shown above.
FS1

m1-22am1-22bm1-22c