REFLECTING AUTOCOLLIMATING SPECTROMETER Russian patent published in 2014 - IPC G01J3/16 G02B17/06 

FIELD: physics.

SUBSTANCE: spectrometer consists of an entrance slit lying in the focal plane of a lens and shifted in the meridian plane relative to its optical axis, the lens and a dispersing device. The lens consists of a first concave mirror with a positive optical power, whose concave surfaces faces the entrance slit, a second convex mirror with a negative optical power, lying between the entrance slit and the first mirror and facing the first mirror with its convex surface, a third concave mirror with a positive optical power, lying behind the second mirror and facing the entrance slit with its concave surface. The dispersing device includes a dispersing element and a flat mirror lying at an angle of 80…90° to incident beams. Optical surfaces of at least two mirrors are aspherical. Centres of curvature of all mirrors lie on the optical axis of the lens. The first and second mirrors are off-axis mirror fragments. The third mirror lies on the optical axis. The dispersing element is a prism with an angle of refraction of 5…30°, made of material with a refraction index of 1.4…1.7 and a dispersion coefficient for line e of 20…70. The flat mirror is in form of a reflecting coating on the second face of the prism in the direction of the beam.

EFFECT: high manufacturability, smaller size and weight, easy adjustment, high image quality and correcting curvature of spectral lines.

4 cl, 4 dwg, 1 tbl