Phase shift device including metal-dielectric composite structure

An image sensor comprising:

• a sensor substrate comprising a plurality of photosensitive cells that are configured to convert light into electrical signals;
• a color filter array disposed on the sensor substrate;
• and
• a lens array disposed on the color filter array, the lens array comprising a plurality of flat lenses;
• wherein each of the plurality of flat lenses comprises:
• a plurality of stacked structures, each of the plurality of stacked structures comprising a metal layer and a first dielectric layer, the metal layer and the first dielectric layer being alternately stacked in a vertical direction;
• and
• a plurality of second dielectric layers alternately disposed with the plurality of stacked structures in a horizontal direction,
• wherein the first dielectric layer comprises a first material having a first dielectric constant and each of the plurality of second dielectric layers comprises a second material having a second dielectric constant,
• wherein the first material is different from the second material, and
• wherein the second dielectric constant is greater than the first dielectric constant.

A camera module comprising:

• a lens assembly;
• an image sensor;
• and
• an image signal processor,
• wherein the image sensor comprises:
• a sensor substrate comprising a plurality of photosensitive cells that are configured to convert light into electrical signals;
• a color filter array disposed on the sensor substrate;
• and
• a lens array disposed on the color filter array, the lens array comprising a plurality of flat lenses;
• wherein each of the plurality of flat lenses comprises:
• a plurality of stacked structures, each of the plurality of stacked structures comprising a metal layer and a first dielectric layer, the metal layer and the first dielectric layer being alternately stacked in a vertical direction;
• and
• a plurality of second dielectric layers alternately disposed with the plurality of stacked structures in a horizontal direction,
• wherein the first dielectric layer comprises a first material having a first dielectric constant and each of the plurality of second dielectric layers comprises a second material having a second dielectric constant,
• wherein the first material is different from the second material, and
• wherein the second dielectric constant is greater than the first dielectric constant.