Optical sensor and image sensor including graphene quantum dots

An image sensor comprising:

• a first optical sensing layer;
• a second optical sensing layer;
• a common electrode connected to the first optical sensing layer and the second optical sensing layer;
• a first pixel electrode connected to first optical sensing layer;
• a second pixel electrode connected to second optical sensing layer;
• a first color filter disposed to correspond to the first optical sensing layer, the first color filter being configured to transmit light of a first wavelength band;
• and
• a second color filter disposed to correspond to the second optical sensing layer, the second color filter being configured to transmit light of a second wavelength band different from the first wavelength band,
• wherein the first optical sensing layer and the second optical sensing layer comprises a plurality of first graphene quantum dots bonded to a first functional group such that the plurality of first graphene quantum dots absorb the light of the first wavelength band and a plurality of second graphene quantum dots bonded to a second functional group different from the first functional group such that the plurality of second graphene quantum dots absorb the light of the second wavelength band.