US Patent 11644643 Optical imaging system

An optical imaging system includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens sequentially disposed in numerical order along an optical axis of the optical imaging system from an object side of the optical imaging system toward an imaging plane of the optical imaging system; and a spacer disposed between the sixth and seventh lenses, wherein the optical imaging system satisfies 0.5<S6d/f<1.4, where S6d is an inner diameter of the spacer, f is an overall focal length of the optical imaging system, and S6d and f are expressed in a same unit of measurement.