TELESCOPIC OPTICAL SYSTEM (VERSIONS) Russian patent published in 2009 - IPC G02B23/00 

FIELD: instrument engineering.

SUBSTANCE: system can be used for operation in beam forward trace and flyback, e.g. as an afocal attachment for variable-magnification visualising instruments and in laser systems. The system comprises a first component that represents an einzel negative lens, and a second component consisting of two positive lenses with the first being einzel, and the second representing glued negative and positive lenses. According to the first version, the lens of the first component is biconcave, whereas the first lens of the second component is a meniscus with convexity facing an image, while the second lens is glued biconcave and biconvex lenses. The relation |R₁ ^2k| = |R₃ ^2k| = |R₄ ^2k| is observed, wherein R₁ ^2k; R₃ ^2k; R₄ ^2k are radiuses of the first, third and fourth optical surfaces of the second component. According to the second version, the lens of the first component is plano-concave. Lenses of the second component are meniscuses with their convexities facing an image. The relation |R₁ ^2k| = |R₄ ^2k| is observed.

EFFECT: higher diametre of entrance pupil and angular field within object space with high image quality.

5 cl, 2 dwg