OPTICAL THERMAL IMAGING SYSTEM FOR MID-INFRARED SPECTRAL REGION Russian patent published in 2015 - IPC G02B13/14 G02B13/16 G02B9/62 

FIELD: physics.

SUBSTANCE: system comprises an input lens, a projection lens, a compensation element and a defocusing element. The input lens constructs an intermediate real image and is in the form of a positive meniscus whose convex side faces the object space, a negative meniscus whose convex side faces the object space. The projection lens comprises a negative meniscus whose convex side faces the object space, a biconvex lens and a positive meniscus whose convex side faces the object space. The compensation element is placed between the input lens and the plane of the intermediate real image such that it can move along the optical axis, the compensation element being a positive meniscus whose convex side faces the object space. The defocusing element is in the form of plane-parallel plate and is installed such that it can enter and exit the space between the compensation element and the plane of the intermediate real image.

EFFECT: fewer optical components, compensation for thermo-optical and thermo-baric aberrations without changing the length of the optical system while maintaining image quality by changing the shape of the lenses and optimising aberrations.

3 dwg, 1 tbl