λ /2 rather than λ /2, again for reliability. All plates are pol- ished flat to better than λ /40 at 10.6m and parallel to less than 5 arc seconds. They are supplied anti-reflection coated at the design wavelength.Waveplates are available as unmounted elements or mounted elements in rotators with optical bench mounts. Վ /4, 7 ێ /4, or 9 ێ /4. The net effect at that the design wave-length is basically the same, but the devices are far less fragile. Half-wave plates are made at 3 > Providing: ە Operating with CO > λ λ /4 plates) Rotating plane of polarization ( /2 plates) > For: Օ Altering beam polarization character Converting linear to circular polarization ( > 2 , CO, or HF-DF and other IR lasers Օ Apertures up to 1.0" Low insertion loss Օ Visible transparency for ease of alignment Convenient rotating mounts for optical bench mounting ՎԎ )twhere ׎Ԏ is the birefringence and t the plate thickness. When d is equal to one quarter of the wavelength and the optic axis is at 45װ to the incoming polariza- tion, the outgoing polarization is circular. When it is equal to one-half of the wavelength being used, the output polarization is linear but rotated with respect to the input polarization by twice the angle between the incoming polarization and the optic axis.The calculated thickness for a quarter waveplate of CdS at 10.6m is approximately 0.01 inch, which is too thin for manu- facturing. Therefore, plates are made at odd multiples of the quarter-wave thickness, i.e., 5 > When a plane-polarized beam is incident on a birefringent plate whose optic axis lies in the plane of the plate, the beam is resolved into two components. These components propogate through the plate with different velocities and recombine upon exiting with a new polarization. The character of the polarization depends upon the orientation of the optic axis and the net difference in optical path length for the two components. This difference, d, is given byd=( > Plate Diameter 0.4, 0.6, 0.8, and 1.0"Clear Aperture (when mounted) Plate diameter minus 0.05" Retardation Accuracy ձ2 @ 10.6еm; 4Ѱ @ 5.3m Bandwidth (for 6հ error) 0.1ѵm @ 10.6m Retardation Range 0 to 360հ Transmission >98.5% @ 10.6m > TECHNICAL DATA SHEET 888-558-1504 (toll-free) Օ 724-352-1504 (phone) 724-352-4980 (fax) Օ www.iiviinfrared.com >