Abstract: The U.S. software for calculating atmospheric transmission characteristics, LOWTRAN, is used to analyze the atmospheric transmission ratio based on conventional formulae within metrological visible range, as well as the medium wave and long wave infrared transmission ratios. The results show that the visible light spectrum transmission ratio and the mean transmission ratio under standard U.S. atmospheric conditions can be favorably described by the metrological visible range transmission ratio formula, but the adaptability to ultraviolet and infrared wave bands needs to be treated with caution. Under high temperature and moist conditions, the atmospheric transmission ratio for the medium infrared wave band will degenerate more rapidly at its initial pathway, but beyond a certain range the mean atmospheric transmission ratio of the medium infrared wave band will be better than that of the long wave band.