IR MIRROR-LENS OBJECTIVE Russian patent published in 2006 - IPC G02B17/08 

FIELD: IR-imaging devices.

SUBSTANCE: objective can be used in far or middle IR-range. Objective has first positive lens made in form of menisci turned with its convexity to object; negative menisci lens turned with its concavity to object, with ring-shaped mirror reflecting layer which is applied onto second surface and which acts as function of main mirror; sphere-shaped counter mirror which is turned with its convexity to image and which is disposed between first and second lenses; and positive menisci which is turned with its concavity to image and which is disposed between counter mirror and plane of images in convergent bundle of rays. Second lens has opening in central part. Protecting mirror (flat-parallel plate) can be mounted between objective and behind it. All the lenses in objective can be made of material being transparent for IR-wavelength range from 3 to 5 mcm or for far spectral IR-range from 8 to 12.5 mcm.

EFFECT: increased focal length and rare section of objective; widened spectral range; improved quality of image.

5 cl, 1 dwg