VARIABLE FOCUS LENS Russian patent published in 2015 - IPC G02B15/16 G02B9/64 

FIELD: physics, video.

SUBSTANCE: invention can be used in video cameras with a CCD array. A variable focus lens comprises four components and an aperture diaphragm placed in front of the fourth component. The first and fourth components are positive, the second and third components are negative and are capable of moving along an optical axis. The first component comprises a positive lens, glued from a negative meniscus and a biconvex lens, a positive lens and a positive meniscus. The second component comprises a negative meniscus, a biconcave lens and a positive meniscus. The third component is negative and is glued from a positive meniscus and a biconcave lens. The fourth component comprises a double-glued lens from a biconvex and a biconcave lens, a positive meniscus, a negative meniscus, a biconvex lens, two negative menisci and a biconvex lens. Relationships given in the claim are satisfied.

EFFECT: wider field of view and reduced relative distortion while maintaining high image quality in the entire measurement range of focal distance of the variable focus lens, which is not less than 5,5 units.

7 dwg