Large-aperture high-resolution marine observation optical system with high adaptability

The invention relates to a large-aperture high-resolution marine observation optical system with high adaptability, which comprises a front lens group A, a diaphragm B, a rear lens group and an optical filter D which are sequentially arranged along a light incidence direction, the front lens group A comprises a positive meniscus lens A-1, a negative meniscus lens A-2, a first cemented lens group formed by tightly connecting a biconcave lens A-3 and a biconvex lens A-4, and a second cemented lens group formed by tightly connecting a biconvex lens A-5 and a biconcave lens A-6, which are sequentially arranged along the light incidence direction; and the rear lens group C comprises a third glued lens group, a biconvex lens C-3 and a biconvex lens C-4 which are sequentially arranged along the light incidence direction, wherein the third glued lens group is formed by tightly connecting a biconcave lens C-1 and a biconvex lens C-2. The invention provides the lens with the maximum image surface of phi 17.6 mm and the