Patent attributes
An optical imaging system includes, in order from an object side to an image side, a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element and a sixth lens element. The first lens element with positive refractive power has an object-side surface being convex in paraxial region. The second lens element has refractive power. The third lens element has positive refractive power. The fourth lens element has refractive power. The fifth lens element with refractive power has an image-side surface being concave in a paraxial region, wherein an object-side surface and the image-side surface are both aspheric. The sixth lens element with refractive power has an image-side surface being concave in a paraxial region, wherein an object-side surface and the image-side surface are both aspheric, and the image-side surface has at least one convex shape in an off-axis region.
