Aspheric optics for the far infrared range

For most situations, spherical optics are used to focus laser beams. For applications requiring a very short focal length, spherical aberrations can become an issue. Aspheric lenses with at least one free-form surface produced using CNC polishing techniques can greatly reduce this effect. Ideally, aspherical lenses replace a system of several spherical lenses, thereby reducing weight and losses through surface scattering.