Abstract: The present disclosure discloses an optical imaging system including, sequentially from an object side to an image side along an optical axis, a first lens having positive refractive power; a second lens having negative refractive power; a third lens having positive refractive power; and a fourth lens having negative refractive power. A distance TTL along the optical axis from an object-side surface of the first lens to an imaging plane of the optical imaging system and a distance To along the optical axis from a to-be-captured object to the object-side surface of the first lens satisfy 1<TTL/To<2.5.

Abstract: The present disclosure discloses an optical imaging lens group including, sequentially from an object side to an image side along an optical axis, a first lens having a positive refractive power; a second lens having a negative refractive power; a third lens having a refractive power; a fourth lens having a refractive power, and an image-side surface thereof being a concave surface; a fifth lens having a refractive power; a sixth lens having a refractive power, and an object-side surface thereof being a convex surface; and a seventh lens having a negative refractive power. A distance TTL along the optical axis from an object-side surface of the first lens of the optical imaging lens group to an imaging plane of the optical imaging lens group and a total effective focal length f of the optical imaging lens group satisfy TTL/f<1.

Abstract: The disclosure provides an optical imaging system, which sequentially includes from an object side to an image side along an optical axis: a first lens with a refractive power; a second lens with a refractive power, an image-side surface thereof is a concave surface; a third lens with a refractive power; a fourth lens with a refractive power; a fifth lens with a refractive power, an object-side surface thereof is a convex surface; a sixth lens with a refractive power; a seventh lens with a refractive power, an object-side surface thereof is a convex surface; and an eighth lens with a refractive power. Semi-FOV is a half of a maximum field of view of the optical imaging system, and Semi-FOV satisfies Semi-FOV<30°.

Abstract: The present disclosure discloses an optical imaging system including, sequentially from an object side to an image side along an optical axis, a first lens having positive refractive power; a second lens having negative refractive power; a third lens having positive refractive power; and a fourth lens having negative refractive power. A distance TTL along the optical axis from an object-side surface of the first lens to an imaging plane of the optical imaging system and a distance To along the optical axis from a to-be-captured object to the object-side surface of the first lens satisfy 1<TTL/To<2.5.

Abstract: The present disclosure discloses an optical imaging lens group including, sequentially from an object side to an image side along an optical axis, a first lens having a positive refractive power; a second lens having a negative refractive power; a third lens having a refractive power; a fourth lens having a refractive power, and an image-side surface thereof being a concave surface; a fifth lens having a refractive power; a sixth lens having a refractive power, and an object-side surface thereof being a convex surface; and a seventh lens having a negative refractive power. A distance TTL along the optical axis from an object-side surface of the first lens of the optical imaging lens group to an imaging plane of the optical imaging lens group and a total effective focal length f of the optical imaging lens group satisfy TTL/f<1.