Waveplates are necessary elements for variable beam attenuators, beamsplitters and optical isolators. Waveplates (retardation plates or phase shifters) are made from optical glass that 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.

In the case of an incident linearly polarized beam this is given by a=2pd(ne-no)/l(a-phase difference; d-thickness of waveplate; ne, no-refractive indices of extraordinary and ordinary rays respectively; l-wavelength).

At any specific wavelength the phase difference is governed by the thickness of the retarder.


-Materials: Single crystal quartz

-Optical Axis: Normal to flat edge on circumference of Retarder

-Angle of Incidence: 0

-Retardation Tolerance: ≤λ/300; ≤λ/500

-Diameter Tolerance: 0/-0.1mm

-Surface Quality: Ultrafine laser polish, 20-10 scratch and dig

-Wavefront distortion: l/10 over central 90% of aperture at 632.8 nm

-Wavelength: 260-1800 nm

-Parallelism: 1 arc second

CPG Optics is able to provide kinds of waveplates as follows:

  • Half Waveplates

  • Quarter Waveplates

  • Dual-Wavelength Waveplates

  • Zero-order Waveplates

  • True Zero-order Waveplates

  • Low-order Waveplates

  • Multi-order Waveplates