====== Anti-reflection with Quarter Wave Plate ======

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A laser beam is directed at a polarizing filter followed by a quarter wave plate and a mirror. The mirror reflects the beam back though the wave plate and polarizer and onto a projection screen. If the quarter wave plate is properly oriented the beam viewed at the projection screen will be severely attenuated.

====Setup====

On an optical rail, install the laser, the polarizer, the wave plate and a mirror in this order. All surfaces must be normal to the beam. Align the mirror so that the beam passes again through the wave plate and polarizer and then hits a screen. Note that if the laser is too powerful, attenuation may be hard to see since the optics may not be rated for the specific wavelength.

L0, L1

PIRA DCS 6H35.40