Double sided meta lens and electronic device including the same

A double sided meta lens comprising:

• a substrate having a first surface and a second surface facing each other;
• a first meta lens that comprises a plurality of first nanostructures arranged on the first surface of the substrate and exhibits a first phase profile;
• and
• a second meta lens that comprises a plurality of second nanostructures arranged on the second surface of the substrate and exhibits a second phase profile,
• wherein the first phase profile is configured such that a central region of the first meta lens operates as a convex lens and a peripheral region of the first meta lens operates as a concave lens, and
• the second phase profile corresponds to a focusing lens and has a section in which an absolute value of a phase slope increases with distance from a center of the second meta lens,
• wherein the first phase profile is expressed by
• ∑
• n
• a
• n
• ·
• (
• r
• R
• 1
• )
• 2
• ⁢
• n
• ,
• where R1 is an effective radius of the first meta lens, and r is a distance from a center of the first meta lens, and
• wherein the second phase profile is expressed by
• ∑
• n
• b
• n
• ·
• (
• r
• R
• 2
• )
• 2
• ⁢
• n
• ,
• where R2 is an effective radius of the second meta lens, and r is a distance from the center of the second meta lens, and
• wherein coefficients an and bn are optimized to minimize a difference between an input image and an image reconstructed using a reconstruction algorithm,
• wherein the section of the second phase profile is in a region where a distance from the center of the second meta lens ranges from R2/2 to R2.