Photonic crystal temperature sensor

The utility model discloses a photonic crystal temperature sensor, which belongs to the field of photonic crystal temperature sensors and comprises a mounting box, a photosensitive switch, a shading plate, a temperature sensitive polymer, a rotating cover, a transparent plate and an elastic fixing structure. Light penetrates through the transparent plate, enters the mounting box and then penetrates through the temperature-sensitive polymer, when the temperature is higher than 33 DEG C, the temperature-sensitive polymer changes to be white, then the light is shielded, the light acting on the light activated switch is reduced, the light activated switch generates an action signal, and the light activated switch is started. The photosensitive switch is connected with an external controller, the shading device of the greenhouse can be conveniently controlled through the controller, the rotating cover on the mounting box can be unlocked or locked through the elastic fixing structure, the temperature-sensitive poly