WAVEPLATE RETARDANCE CALCULATOR

(click above link to start calculator)

Zero order waveplates are constructed from two multi order waveplates that have their fast axes rotated 90 degrees with respect to each other so that the two retardances subtract. The net result is a compound waveplate with a net retardance equal to the difference between the two waveplates.

This results in a waveplate that has a spectra bandwidth and temperature bandwidth equivalent to a true zero order waveplate (note: the angle-of-arrival dependency is higher due to the longer optical path).

The two waveplates are air spaced and bonded using an epoxy adhesive. All of our waveplates are AR coated with a V-coat at the design wavelength and are available unmounted or mounted in an anodized aluminum 1" mount.

Our true zero order waveplates are precision polished to a zero order retardance thickness. This results in a waveplate with the least sensitivity to wavelength, temperature, and angle of arrival.

The thickness of a waveplate is determined by the desired retardance, operating wavelength, and the birefringence of the material. A true zero order quartz waveplate is typically very thin (i.e. quarter wave at 633nm is only 17.5μm thick). However, due to the change in birefringence with wavelength, a practical thickness can be achieved only at longer wavelengths.

We offer half wave and λ/4 wave true zero order waveplates at the popular telecom wavelength, 1550nm (note: the λ/4 wave can be used like a quarter waveplate with a sign reversal).

Our standard sizes are 2mm x 2mm and 5mm x 5mm. These are also available in custom sizes.

Multi-order waveplates are single plate waveplates with a thickness that results in a retardance equal to the design retardance plus some multiple of full wave retardances. Because they are made from a single plate they are less expensive than zero order waveplates and are used where sensitivity to wavelength and temperature is not critical.

Our standard multi order waveplates 0.5" diameter by approximately 1mm thick. These are also available in custom sizes.

Dual wavelength waveplates are multi-order waveplates designed to simultaneously meet specific retardances at two different wavelengths. Dual wavelength waveplates have been used in second harmonic generation (SHG) lasers and optical parametric oscillators (OPO) where it is sometimes useful to have separate polarization states for the fundamental and the harmonic beams.

Dual wavelength waveplates are designed for a thickness that optimally meets the design retardances of the two wavelengths to within a certain precision. We have developed models to design and accurately predict the performance of dual wavelength waveplates. Most common are the 1064nm / 532nm designs for SHG Nd:Yag and Nd:YVO4 lasers. We have standard designs for these two wavelengths as well as others.

Fresnel rhombs work on the principal of total internal reflection (TIR). The rhombs are a parallelepiped shape where the beam is designed to enter one of the faces and reflect off of two side surfaces prior to exiting the rhomb. Each reflection contributes a phase shift equal to λ/8 wave retardance, therefore the output is phase shifted by a total λ/4 wave retardance.

Unlike quartz waveplates, Fresnel rhombs are inherently less sensitive to wavelength (i.e. achromatic) since the phase shift is a function of the glass index which varies only slightly over the design wavelength range. The wavelength varies less than +/-2% over a range from 600nm to 1550nm

Each Fresnel rhomb is designed for a λ/4 wave retardance. The λ/2 wave rhombs use two λ/4 rhombs cemented together.

We can also manufacture UV rhombs as well as air-spaced rhombs for high power applications.