Imaging system

The utility model discloses an imaging system, and the system comprises a lens group which comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens which are sequentially arranged from an object side to an image side along an optical axis, the second lens and the fifth lens have negative focal power, the fourth lens has positive focal power, and the sixth lens has negative focal power; the curvature radius of the image side surface of the fifth lens is greater than zero; and a plurality of spacer elements including a second spacer element in contact with the image side portion of the second lens, a third spacer element in contact with the image side portion of the third lens, a fourth spacer element in contact with the image side portion of the fourth lens, and a fifth spacer element, the object-side inner diameter and the image-side inner diameter of at least one of the plurality of spacing elements are unequal and/or the object-side outer diameter and the image-side