GRADIENT LENS ( VARIANTS ) Russian patent published in 2004 - IPC

FIELD: gradient optics, fiber optics and optical instrumentation. SUBSTANCE: gradient lens is produced from material with radial gradient of refractive index and is limited by first and second refraction surfaces. First surface is flat, second reflection surface comes in the form of surface of revolution with generatrix found from equation given in formula of invention. Second surface can be approximated by surface of second order, specifically, spherical. According to second variant of production of lens its thickness is established from relation specified in formula of invention. EFFECT: increased quality of image due to reduced spherical aberration and change of its sign, raised numerical aperture of lens. 15 cl, 36 dwg