1.High Damage Threshold 2.Low Cost 3.Thickness:0.2-0.5mm Wave plate using birefringent crystal materials, resulting in phase with the incident and the incident light to produce a phase difference of λ / 4 (π / 2,90 °), or λ / 2 (π, 180 °) of the beam.Wave plate can be divided into a multi-polar plate, zero-wave plate and true zero-wave plate and so on, and true zero-zero-wave plate is divided ...