Image sensor and electronic device including same

An image sensor includes: a sensor substrate including first, second, and third pixels sensing light of first, second, and third wavelengths, respectively; and the color separation lens array changes the phases of the light of the first wavelength, the second wavelength and the third wavelength, and converges the phase change light onto the first pixel, the second pixel and the third pixel respectively. The dichroic lens array includes first to third pixel corresponding regions facing the first to third pixels, respectively. The first pixel corresponding region includes a plurality of first nano-pillars, the second pixel corresponding region includes a plurality of second nano-pillars, and the third pixel corresponding region includes a plurality of third nano-pillars, a second central nano-pillar having the largest cross-sectional width among the second nano-pillars overlaps the center of the second pixel, and a second central nano-pillar having the largest cross-sectional width among the third nano-pillars