FOUR-ELEMENT TELEPHOTO LENS Russian patent published in 2006 - IPC G02B13/02 G02B9/10 

FIELD: optical instrument engineering, applicable in various optical systems, the infrared systems inclusive.

SUBSTANCE: the four-element telephoto lens has two components, the first of which is a positive one and consists in its turn of three sticked lenses - of positive and negative menisci turned by the convexity to the object, and a flat-convex lens turned by the convexity to the object, and the second component - a flat-concave lens turned by the concavity to the object. The relations indicated in the claim are realized in the telephoto lens.

EFFECT: enhanced focal length and the relative aperture, simplified construction and enhanced adaptability to manufacture at a high quality of image.

3 cl, 1 dwg