Optical device, and window provided with light distribution function

An optical device comprising:

• a supporting substrate;
• and
• a plurality of optical elements which are aligned above the supporting substrate in a first direction,
• each of the plurality of optical elements including:
• a substrate which is light-transmissive;
• a first electrode which is disposed above the substrate;
• an uneven layer which is disposed above the first electrode;
• a refractive-index adjustment layer which is disposed above the uneven layer;
• and
• a second electrode which is disposed above the refractive-index adjustment layer,
• wherein the plurality of optical elements include optical elements which are adjacent to each other and separation regions are each formed between adjacent one of the plurality of optical elements, and
• at least one of areas of the plurality of optical elements in a plan view and areas of the plurality of separation regions vary successively in the first direction.