Optical imaging systems and imaging units

Abstract

The invention relates to an optical imaging system comprising eight lens elements in order from object side to image side along the optical path: the first lens element, the second lens element, the third lens element, the fourth lens element, the fifth lens element, the sixth lens element, the seventh lens element, and the eighth lens element. Each of the eight lens elements has an object side surface and an image side surface. The object-facing surface of the third lens element is concave in its axial region. The fourth lens element has positive refractive power. The fifth lens element has positive refractive power. The sixth lens element has positive refractive power. The seventh lens element has negative refractive power, and the image-facing surface of the seventh lens element is concave in its axial region. The invention also reveals the photographic assembly including this optical photographic system.