IMAGING OPTICAL SYSTEM, IMAGING DEVICE, AND VEHICLE

WIPO Patent Application WO/2021/192894

A1

The present invention comprises: a first lens group including a first lens having a positive refractive power, a second lens having a negative refractive power, and a third lens having a positive refractive power in this order from an object side or including a first lens having a negative refractive power and a second lens having a positive refractive power in this order from the object side, the first lens group having a negative refractive power in total; at least one on-axis light flux regulation diaphragm; and a second lens group having a positive refractive power, wherein the object-side surface of the lens having a negative refractive power in the first lens group is a convex surface on a paraxial axis and has an aspherical shape in which convex power weakens as the surface is farther from the optical axis, the most image-side surface of the second lens group has a shape convex toward the image side on the paraxial axis, and the following conditional expressions (1) to (3) are satisfied.　-1.30