Micro Waveplate

Material: Crystal Quartz
            Dimension: +0.0, -0.2mm
            Wavefront Distortion : < λ /8@632.8 
            Retardation tolerance : < λ /500 
            Parallelism : <1 arc second 
            Surface Quality: 20/10 scratch and dig 
            AR coating : R<0.2% at central wavelength 
            Standard Wave: quarter-wave (λ /4), half-wave (λ /2)