The ISTMT test is mainly a temperature rise test, and the test standards are mainly IEC 60598, UL1598. At present, this project needs to be tested mainly include DLC, ENERGY STAR and CEC in the United States; VEET and IPART in Australia. Mainly test the lamp bead temperature and driving temperature in the lamp, so as to estimate the life of the whole lamp according to the LM-80 report and TM-21.