Abstract: A set of instrument has been built up by means of the combination of a schlieren with a one dimension array of ultraviolet opticelectrical diode and a simultaneously triggered oscilloscope, which is use in monitoring and measurement the damage state and the threshold on the high reflection (HR) and the anti reflection (AR) coatings under the irradiation of the 308nm excimer laser. By this instrument, the waveforms of the whole damage process which contained the initial, the deepening and the saturated sestages of the damage, have been investigated. The measured damage threshold is about 1.7 J/cm2 at zero incident angle and 1.0 J/cm2 at 45°incident angle for the HR coating, and 1.29 J/cm2 for the AR coating. And also some analysis about the experiment result has been given damage.