◆Waveplate：       Waveplates (retardation plates or phase shifters) are made from materials which exhibit birefringence. The velocities of the extraordinary and ordinary rays through the birefringent materials vary inversely with their refractive indices. The difference in velocities gives rise to a phase difference when the two beams recombine. At any specific wavelength the phase difference is governed by the thickness of the retarder。 ·Specifications：

Material: Crystal Quartz Dimension allowance: +0.0, -0.15mm Phase contrast Retardation : λ/8,λ/4,λ/2, or discretional Wavefront distortion: ≤λ/4@632.8nm barring Cemented Waveplate Retardation tolerance: ≤λ/300、≤λ/500 Wavelength range: 260-1600 nm Parallelism: ≤1 arc second Surface quality: 20/10 scratches and dig Clear aperture: ≥90% AR coating: R≤0.25% at central wavelength

·Half Waveplate       The thickness of a half waveplate is such that the phase difference is 1/2-wavelength (true-zero order) or some multiple of 1/2-wavelength (multiple order). ·Quarter Waveplate       The thickness of the quarter waveplate is such that the phase difference is 1/4 wavelength (true-zero order) or some multiple of 1/4 wavelength (multiple order) ·Multi-Order Waveplate

•Thickness: 1 mm •Single plates •High Damage Threshold •Low Cost

·Low Order Waveplate

•Thickness: 0.2-0.6 mm •High Damage Threshold •Better Temperature Bandwidth •Low Cost

·True Zero-Order Waveplate

•Wide Angle Acceptance •Better Temperature Bandwidth •High Damage Threshold •Better Wide Wavelength Bandwidth •Standard Wavelengths: 1064, 1310, 1550nm…

·Cemented Zero-Order Waveplate

•AR Coated •Better Temperature Bandwidth •Better Wide Wavelength Bandwidth

·Cemented True Zero-Order Waveplate

•Cemented by UV Epoxy •Wide Angle Acceptance •Better Temperature Bandwidth •Better Wide Wavelength Bandwidth

·Cemented Broad-band Zero-Order Waveplate

•Cemented by UV Epoxy •Wide Angle Acceptance •Better Temperature Bandwidth •Better Wide Wavelength Bandwidth •Quaternity Plates

·Comparison of Waveplates

Order of Waveplate Multi Low Cemented Zero Cemented Broad-band Zero Total Thickness (mm) ~1 ≤0.5 1.5~2 1.5~3 Spectral Bandwidth  (nm) 0.5 1.5 30 110 Per Picture 2 A 　 B C

Note: Picture 2 curves are measured by Picture 1 instruments, which are got different bandwidith of Multi(A) / Cemented Zero(B) / Cemented Broad-band(C) Zero Waveplates.