An optical device is provided in the present application. The optical device of the present application has varying transmittance and improved appearance defects, such as reduction of wrinkles that may occur by lamination of a liquid crystal element and an outer substrate. Such optical device can be used for various applications such as eyewear, for example, sunglasses or AR (augmented reality) or VR (virtual reality) eyewear, an outer wall of a building or a sunroof for a vehicle.