Abstract: The present disclosure relates to zoom lenses and optical devices using the same. A zoom lens may include in order from an object side to an image side: a first lens group, a second lens group, a third lens group, a fourth lens group; and a fifth lens group. The zoom lens may satisfy the following conditions: ?2.28?f2/fw???1.08, and 0.15?TTL/(BFL*fw?)?0.45, wherein f2 denotes a focal length of the second lens group, fw? denotes a focal length of the zoom lens at a wide angle end, TTL denotes a total track length of the zoom lens, and BFL denotes a back focal length of the zoom lens.

Abstract: The present disclosure relates to zoom lenses. A zoom lens may include in order from an object side to an image side: a first lens group; a second lens group; a third lens group; a fourth lens group; and a fifth lens group; wherein the zoom lens satisfies certain conditions.

Abstract: The present disclosure is related to a lens systems. The lens system includes, in order from an object side to an image side, a first lens group G1 having negative refractive power, a second lens group G2 having positive refractive power, a third lens group G3 having positive refractive power, and the lens system satisfies the a ? f 1 f ? ? b , c ? f 2 f ? ? d , e ? f 3 f ? ? f , following condition: and at least partial of G3 is made of material satisfying the following condition: Vd>g and dn/dt?h, wherein a, b, c, d, e, f, g and h are constants, f1 represents a focal length of G1, f2 represents a focal length of G2, f3 represents a focal length of G3, f? represents a focal length of the lens system, Vd represents an abbe constant, n represents a refractive index, t represents temperature, and dn/dt represents a differential of refractive indices against temperature.

Abstract: The present disclosure relates to zoom lenses and optical devices using the same. A zoom lens may include in order from an object side to an image side: a first lens group, a second lens group, a third lens group, a fourth lens group; and a fifth lens group. The zoom lens may satisfy the following conditions: ?2.28?f2/fw???1.08, and 0.15?TTL/(BFL*fw?)?0.45, wherein f2 denotes a focal length of the second lens group, fw? denotes a focal length of the zoom lens at a wide angle end, TTL denotes a total track length of the zoom lens, and BFL denotes a back focal length of the zoom lens.

Abstract: The present disclosure relates to a lens system and an imaging device including the lens system. The lens system may include a first lens group, a second lens group, a third lens group, a fourth lens group, and a fifth lens group in sequence from an object side to an image side along an optical axis of the lens system. At least one of the first lens group, the second lens group, the third lens group, the fourth lens group, and the fifth lens group may be adjustable along the optical axis of the lens system to adjust a focal length of the lens system. The lens system may satisfy a ? f 2 ( f w · f t ) 1 / 2 ? b , c ? f 3 ( f w · f t ) 1 / 2 ? d , e ? f 4 ( f w · f t ) 1 / 2 ? f .

Abstract: The present disclosure relates to zoom lenses and optical devices using the same. A zoom lens may include in order from an object side to an image side: a first lens group; a second lens group; a third lens group; a fourth lens group; and a fifth lens group; wherein the zoom lens satisfies the following conditions: ?1.7?f2/fw???0.3, 0.7?f3/fw??2.1, 1.1?f4/fw??2.5, and TTL/fw??6.5, wherein f2 denotes a focal length of the second lens group, f3 denotes a focal length of the third lens group, f4 denotes a focal length of the fourth lens group, fw? denotes a focal length of the zoom lens, and TTL denotes a total track length of the zoom lens.

Abstract: The present disclosure is related to a lens systems. The lens system includes, in order from an object side to an image side, a first lens group G1 having negative refractive power, a second lens group G2 having positive refractive power, a third lens group G3 having positive refractive power, and the lens system satisfies the a ? f 1 f ? ? b , c ? f 2 f ? ? d , e ? f 3 f ? ? f , following condition: and at least partial of G3 is made of material satisfying the following condition: Vd>g and dn/dt?h, wherein a, b, c, d, e, f, g and h are constants, f1 represents a focal length of G1, f2 represents a focal length of G2, f3 represents a focal length of G3, f? represents a focal length of the lens system, Vd represents an abbe constant, n represents a refractive index, t represents temperature, and dn/dt represents a differential of refractive indices against temperature.

Abstract: The present disclosure relates to a lens system and an imaging device including the lens system. The lens system may include a first lens group, a second lens group, a third lens group, a fourth lens group, and a fifth lens group in sequence from an object side to an image side along an optical axis of the lens system. At least one of the first lens group, the second lens group, the third lens group, the fourth lens group, and the fifth lens group may be adjustable along the optical axis of the lens system to adjust a focal length of the lens system. The lens system may satisfy a ? f 2 ( f w · f t ) 1 / 2 ? b , c ? f 3 ( f w · f t ) 1 / 2 ? d , e ? f 4 ( f w · f t ) 1 / 2 ? f .

Abstract: A zoom lens system for providing high quality images with higher resolution includes a first lens group (110), an aperture stop (120), and a second lens group (130). The first lens group has a positive or negative refractive power, and includes at least two lens elements having a negative refractive power and at least on lens element having a positive refractive power. The second lens group has a positive refractive power. A distance between a first and second lens group is not fixed.

Abstract: A zoom lens system for providing high quality images with higher resolution includes a first lens group (110), an aperture stop (120), and a second lens group (130). The first lens group has a positive or negative refractive power, and includes at least two lens elements having a negative refractive power and at least on lens element having a positive refractive power. The second lens group has a positive refractive power. A distance between a first and second lens group is not fixed.