Patent ID: 7359119

Claim:
Optical arrangement for pre-processing primary illumination light, comprising: a light entrance section (E) for receiving primary illumination light (L 1 ) transmitted in and received from an incoming direction (Z), a light output section (O) for outputting output light as secondary illumination light (L 2 ) in an irradiating direction (Z′), and a spectral processing section (P) arranged between said light entrance section (E) and said light output section (O) for spectrally processing said primary illumination light (L 1 ) in order to generate said secondary illumination light (L 2 ), wherein said spectral processing section (P) comprises a multi-prism assembly including a plurality of sequentially connected prisms, wherein pairs of adjacent and connected prisms form a respective spectral separating face at faces thereof forming a connecting interface between them, and wherein said spectral separating face is arranged: in order to perform a process of spectral separation with respect to said primary illumination light (L 1 ), in order to generate said secondary illumination light (L 2 ), in order to thereby generate first and second parts of said secondary illumination light (L 2 )which have a pair of complementary spectral components of said primary illumination light, said pair if combined constituting a neutral color and which at the same time remain or are spatially mingled or spatially non-separated.