LEUCO-SAPPHIRE ACHROMATIC MAGNIFYING GLASS Russian patent published in 1997 - IPC

FIELD: optical instruments. SUBSTANCE: device has system of four or three lenses in frame. External lenses are made from leuco-sapphire Al₂O₃. Symmetric magnifying glass has two lenses which are spaced by air gap and glued from external and internal lenses. Asymmetric three-lens magnifying glass is designed as glued external flat-concave lenses and flat-convex internal lens. EFFECT: increased functional capabilities. 5 cl, 6 dwg