US Patent 11391922 Lens assembly including seven lenses of −−+++−+ refractive powers

A lens assembly includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens, all of which are arranged in order from an object side to an image side along an optical axis. The first lens is with negative refractive power and includes a convex surface facing the object side. The second lens is with negative refractive power. The third lens is with positive refractive power. The fourth lens is with positive refractive power. The fifth lens is with positive refractive power. The sixth lens is with negative refractive power. The seventh lens is with positive refractive power and includes a convex surface facing the object side. The second lens and the third lens are cemented.