Lens assembly and electronic device including the same

An electronic device comprising:

• a lens assembly comprising a plurality of lenses arranged from an object side to an image side;
• an image sensor configured to detect an image of the object based on incident light passing through the plurality of lenses sequentially;
• and
• an image signal processor configured to store or output an image,
• wherein the lens assembly comprises:
• a first lens having positive optical power with respect to incident light incident from the object side and having a convex surface facing the object side;
• and
• a second lens comprising a meta-lens having negative chromatic aberration with respect to the incident light passing through the first lens, and
• wherein the meta-lens satisfies the following equation:
• fM1λ1=fM2λ2=fM3λ3,
• where fM1 is a focal length of the meta-lens for light of a first wavelength λ1 of the incident light, fM2 is a focal length of the meta-lens for light of a second wavelength λ2 of the incident light, and fM3 is a focal length of the meta-lens for light of a third wavelength λ3 of the incident light.

A meta-lens comprising:

• nano structures comprising:
• a first phase shift layer configured to react with incident light to change a phase of the incident light;
• and
• a second phase shift layer configured to change the phase of the incident light passing through the first phase shift layer,
• wherein the nano structures are configured to form an identical phase delay profile for at least two different wavelengths of the incident light, and
• wherein a first nano structure of one of the nano structures and a second nano structure adjacent to the first nano structure satisfy the following expressions:
• N11>N21, and
• N12<N22,
• where N11 is an effective refractive index of the first phase shift layer of the first nano structure, N12 is an effective refractive index of the second phase shift layer of the first nano structure, N21 is an effective refractive index of the first phase shift layer of the second nano structure, N22 is an effective refractive index of the second phase shift layer of the second nano structure.

An electronic device comprising:

• a lens assembly comprising a plurality of lenses arranged from an object side to an image side;
• an image sensor configured to detect an image of an object from incident light passing through the plurality of lenses sequentially;
• and
• an image signal processor configured to store or output an image,
• wherein the lens assembly comprises:
• a first lens having positive optical power with respect to incident light incident from the object side and having a convex surface facing the object side;
• a second lens comprising a meta-lens having negative chromatic aberration with respect to the incident light passing through the first lens;
• a third lens having negative optical power with respect to the incident light passing through the second lens and having a concave surface facing the image side;
• a fourth lens having positive optical power with respect to the incident light passing through the third lens and having a concave surface facing the object side;
• a fifth lens having positive optical power with respect to the incident light passing through the fourth lens and having a concave surface facing the object side;
• and
• a sixth lens having negative optical power with respect to the incident light passing through the fifth lens and having a concave surface facing the object side,
• wherein the lens assembly has a modulation transfer function of 0.5 or more at 120 cycles/mm or less for incident light, and
• wherein the electronic device satisfies the following expression:
• TTL/ISS<0.65,
• where a total track length (TTL) is a total track length of the lens assembly and an image sensor size (ISS) is a diagonal length of the image sensor.