Imaging system assembly

The invention discloses an imaging system assembly, the imaging system assembly comprises a focusing assembly and an imaging assembly, the imaging assembly comprises a lens barrel, a lens group and a spacing element group, the lens group and the spacing element group are accommodated in the lens barrel, and the lens group comprises a first lens with positive focal power, a second lens with negative focal power, a third lens with positive focal power, a fourth lens with negative focal power and a fifth lens with negative focal power which are sequentially arranged from an object side to an image side along an optical axis; the object side surface and the image side surface of the fifth lens are convex surfaces; the second lens has negative focal power, and the object side surface and the image side surface of the second lens are concave surfaces; the object side surface of the third lens is a convex surface, and the image side surface of the third lens is a concave surface; the object side surface of the fourt