Diffraction patterns of various gratings using He-Ne laser.

Diffraction patterns of various gratings using He-Ne laser. Monochromatic Helium-Neon laser light passes through a transmission diffraction grating, and the resulting maximas are displayed on a projection screen. The 19,500, 14,438 and 10,000 Lines-per-Inch gratings all have the most light in the 0 order maxima, and less intense beams in the 1st, 2nd and 3rd etc. with maximas spaced symetrically about the 0 order beam. The 4,800 LPI grating has the most light in the 1st order maxima, and the 2nd, 3rd and 4th order maximas etc. are more intense on one side of the 1st order beam. The 2,100 LPI has the most light in the 2nd order maxima and the other maximas are more intense on one side of the 2nd order beam.