TELESCOPE WITH PANCREATIC CHANGE OVER ZOOM FOR FAR INFRARED SPECTRUM Russian patent published in 2008 - IPC G02B23/00 G02B13/14 G02B15/16 

FIELD: physics; optics.

SUBSTANCE: proposed telescope has an invariable position of the exit pupil when changing zoom and comprises a first positive component in form of a positive and a negative meniscus, whose concave side faces the exit pupil, a second negative component from a positive meniscus, whose convex side faces the exit pupil, a biconcave lens, a third positive component in form of a meniscus, whose convex side faces the exit pupil, and a fourth positive component in form of two meniscuses, whose convex sides face each other. All these components are arranged in series along the beam path. The second and third components can move along an optical axis. All refracting surfaces of the telescope are spherical. The negative meniscus of the first component, first meniscuses of the second and fourth components are made from zinc selenide, and the rest of the lenses are made from germanium.

EFFECT: reduced weight and size, reduced distortion, increased differences in zoom by up to ten times with retention of the diffraction quality of the image in the whole field, meeting requirements of limiting the Narcissus effect at the same time.

3 dwg