Patent ID: 7009702

Claim:
A spectrometer with at an optical path for a beam of electromagnetic radiation, the spectrometer comprising: a beam-entry slit for an incoming beam; a collimator for collimating the incoming beam to provide a collimated beam, said collimator comprising a convergent spherical mirror; an aspherical corrector element comprising an aspherical mirror for correction of spherical aberration introduced along the optical path, said aspherical corrector being arranged between said collimator and a dispersor to receive said collimated beam and provide a conditioned collimated beam; said dispersor positioned downstream of said collimator, said dispersor receiving said conditioned collimated beam and dispersing said collimated beam into a dispersed beam comprising chromatic components of said collimated beam; a focusing system downstream of said dispersor receiving said dispersed beam from said disperser and focusing said dispersed beam to provide a focused beam, said focusing system comprising a convergent spherical mirror; and a detector which receives said focused beam from said focusing system, each of said beam entry slit, said convergent spherical mirror, said aspherical mirror, said disperor, and said detector being along said optical path.