The invention discloses a manufacturing method of an 
infrared reflecting device. The manufacturing method of the 
infrared reflecting device comprises the following steps: making a first conductive light transmitting substrate and a second conductive light transmitting substrate at first, and enabling the two conductive light transmitting substrate to opposite to each other; manufacturing parallel orientation 
layers on the opposite surfaces of the two conductive light transmitting substrates; manufacturing a 
liquid crystal box by using the two conductive light transmitting substrates; mixing negative 
liquid crystal, a chiral 
dopant, 
liquid crystal monomers and a 
photoinitiator to obtain a liquid 
crystal mixture; injecting the liquid 
crystal mixture in the liquid 
crystal box; connecting the first conductive light transmitting substrate with a negative pole of a power supply 
assembly, connecting the second conductive light transmitting substrate with a positive pole of the power supply 
assembly, capturing 
impurity positive ions by using the liquid crystal monomers and / or the chiral 
dopant so that the liquid crystal monomers and / or the chiral 
dopant have positive charge, and enabling the liquid crystal monomers and / or the chiral dopant to continue moving towards the negative pole direction; and carrying out 
ultraviolet irradiation to polymerize the liquid crystal monomers so as to form a 
polymer network, and enabling the densities of the 
polymer network to be distributed in a gradient manner in the direction perpendicular to the conductive light transmitting substrate to obtain the 
infrared reflecting device with wide reflection bandwidth. By change of the direction of an 
electric field, infrared reflection waveband can be adjusted.