OPTICAL SYSTEM FOR FOCUS OF RADIATION Russian patent published in 2018 - IPC G02B9/12 

FIELD: optics.

SUBSTANCE: optical system can be used to form image on CCD array and photodetector in non-contact target sensors. Optical system consists of plano-convex lens 1, that is turned by plane surface to image space, single positive meniscus 2, facing concave surface toward image space, and plano-convex lens 3, inverse convex surface to image space. Distance between concave surface of meniscus and plane surface of first lens, reduced to air, is 0.4÷0.42 focal length of optical system. All elements of lens are made of one material with refractive index of 1.51÷1.53 and Abbe number is not more than 70.

EFFECT: technical result is reduction in diameter of focusing spot, number of optical elements and distance between them, simplifying design and manufacturing technology by using single glass grade.

1 cl, 1 dwg, 1 tbl