The invention discloses a method for preparing a large-size three-dimensional
photonic crystal through a constant-temperature liquid baking method. The method is characterized by comprising the following steps that 1,
polymer material colloidal microspheres, a substrate, a dispersion medium, constant-temperature liquid, a first container and a second container are prepared, wherein the particle size of the
polymer material colloidal microspheres is in a
micron size and is uniform, the substrate is obtained through
hydrophilization, the temperature of the constant-temperature liquid is a DEG C,the size of the second container is smaller than that of the first container, and the
thermal conductivity of the second container is good; 2, the
polymer material colloidal microspheres are put intothe dispersing medium, the polymer material colloidal microspheres are dispersed in the dispersion medium through
ultrasonic vibration, and a
mixed solution with the concentration of b% is obtained;3, the constant-temperature liquid is poured into the first container, the second container is put into the constant-temperature liquid to float, the substrate is put into the second container, and the substrate is heated for c minute by using the constant-temperature liquid; 4, the
mixed solution is dropwise added onto the substrate, after a
solvent is volatilized, the constant-temperature liquidis used for continuous heating, and the colloidal three-dimensional
photonic crystal made of the polymer material colloidal microspheres is obtained. The method is novel in concept, reasonable in design and easy and convenient to operate.