The infrared lamp array was used as the radiation heat source to carry out the temperature environment test.In order to improve the uniformity of the temperature distribution on the heated plane by optimizing the lamp array,the model of the infrared lamp irradiance distribution on the heated plane was built.The Monte Carlo method was used to randomly sample the emitting light position and emitting direction,and the emitting light equation was established.The random sampling and tracing of a lot of emitting rays were carried out,and a database of ray placement coordinates was established.The heated plane was divided into grids and the quantity of light spots in each grid were counted.The irradiance distribution was obtained by calculating the radiation illuminance on each grid.Compared with the measured irradiance data,the model could simulate the irradiance distribution of infrared light in a certain range.