A tunable light includes a super continuum light source and a non-linear crystal, the super continuum light source comprising a pump source and a generator fiber, the generator fiber having an input end and an output end, and the super continuum light source and the non-linear crystal being arranged so that at least a part of output light emitted from the output end of the generator fiber is brought into interaction with the non-linear crystal under an angle of incidence φ relative to a surface of the non-linear crystal.