Cylindrical lenses are either circular or rectangular objects with cylindrically shaped surfaces. They're different with spherical lenses because they focus a beam into a focal line rather than a focal point.
High transmission is improved by an anti-reflection coating on both sides. Cylindrical lenses can be made from ZnSe, Ge, Silicon and other IR materials.
Applications include laser scanners, laser diode systems, spectrophotometers, projectors, and optical data storage and retrieval systems.

Specifications
Material	ZnSe Laser Grade C.V.D. type
Diameter Tolerances	+.000", -.005"
Thickness Tolerances	±.010"
Surface Figure	< 1/40 wavelength @ 10.6μ
ETV	< .0015"
Focal Length Tolerance	±1.0%
Surface Quality	< 20/10 scratch-dig Laser Finish
Spectral Performance
Standard AR Coating type Both Sides @ 10.6μm (AR)
Absorption	< 0.20 % total
Reflectance	< 0.20% per surface @ 10.6μm
Transmittance	> 99.4% typical
Ultra Low Absorption AR Coating type Both Sides @ 10.6μm (ULA)
Absorption	< 0.13 % total
Reflectance	< 0.25% per surface
Transmittance	> 99.4% typical
Dual Band AR Coating type Both Sides @ 10.6μm and .633μm (DBAR)
Absorption	< 0.20 % total
Reflectance	< 0.25% per surface @ 10.6μm
Transmittance	> 99.3% @ 10.6μm with > 90% @ .633μm