Knight Optical (UK) Ltd Fresnel Prism 23deg deviation 140x140mm aperture PFA23140

Fresnel prisms are simple prisms but manufactured using the stepped surface approach of a Fresnel lens. Fresnel prisms must not be confused with fresnel rhombs or biprisms. We can offer two types of Fresnel prisms. The simple ones have sawtooth-like structure and will deviate a beam of light by the specified angle, some distortion and colour will be created. The beamsplitters have a symmetrical profile and so create w pair of beams symmetrically about the centreline. In this way they act as beam splitters, there is however still some distortion and colour. The overall size may be up to 20mm larger than the clear aperture. Prism direction runs parallel to long axis