Optical imaging system

Abstract

The present disclosure discloses an optical imaging system. The optical imaging system includes, sequentially from an object side to an image side, a first lens having a negative refractive power; a second lens having a refractive power; a third lens having a negative refractive power; a fourth lens having a refractive power; a fifth lens having a refractive power; a sixth lens having a refractive power; and a seventh lens having a refractive power. There is an air spacing on an optical axis between any two adjacent lenses in the first to seventh lenses. An effective focal length f of the optical imaging system and an entrance pupil diameter EPD of the optical imaging system satisfy: f/EPD≤2.10. The effective focal length f of the optical imaging system and an effective focal length f1 of the first lens satisfy: f1/f>−3.

Dependencies are inferred from the claim text.