OPTICAL LENS AND ELECTRONIC APPARATUS INCLUDING THE LENS

摘要

An imaging optical system includes, in order from the object side to the image side, an aperture stop, a first lens element with a positive refractive power having a convex object-side surface, a second lens element with a negative refractive power having a convex image-side surface in the vicinity of an outer circumference, a third lens element with a positive refractive power having a concave object-side surface in a vicinity of an optical axis and a convex image-side surface in the vicinity of the optical axis, and a fourth lens element having a concave image-side surface in the vicinity of the optical axis and a convex image-side surface in the vicinity of the outer circumference. The sum of thicknesses of the first, second, third, and fourth lens elements and the sum of total air gaps therebetween satisfy specific conditions.

主权项

1. An imaging optical system comprising, in order from an object side to an image side:
an aperture stop; a first lens element with a positive refractive power having a convex object-side surface; a second lens element with a negative refractive power having a convex image-side surface in the vicinity of an outer circumference; a third lens element with a positive refractive power having a concave object-side surface in a vicinity of an optical axis and a convex image-side surface in the vicinity of the optical axis; and a fourth lens element having a concave image-side surface in the vicinity of the optical axis and a convex image-side surface in the vicinity of the outer circumference; wherein a sum of thicknesses of the first, second, third, and fourth lens elements is ALT and a sum of total air gaps between the first, second, third, and fourth lens elements is AAG, and they satisfy the relation:
3.5≦ALT/AAG.