An optical device that can be used for various applications including eyewears, such as sunglasses or AR (augmented reality) or VR (virtual reality) eyewear, an outer wall of a building or a sunroof for a vehicle, and the like is provided. The optical device includes first and second outer substrates disposed to face each other, an active liquid crystal film layer, and a step forming layer. The active liquid crystal film layer and the step forming layer are encapsulated by an encapsulating agent between the first and second outer substrate. The active liquid crystal film layer comprises a first region that is pressed by the step forming layer and a second region that is not pressed by the step forming layer. The defects caused by an excessively large or small amount of light-modulating material or heat shrinkage of the light-modulating material, and the like are prevented in the optical device.