The QWP-25 from Anteral is a Quarter Waveplate that has a frequency band of up to 1.5 THz. It has a gap width of 5 μm and strip width of 10 μm. This waveplate has a clear aperture of 23.9 mm and transmission loss below 1 dB. It has a patterned Cu-Au micro grid array of strips on the topside & continuous conductor on the backside and a rotating frame with angular scale. This waveplate is available in a package that measures 53.5 mm x 12.7 mm x 54.4 mm and is ideal for the generation of circular polarization.