Keywords: 
• laser measurement /
• intensity distribution /
• diffused reflection /
• diffused transmission /
• array detector

Abstract: The measurement of laser intensity temporal-spatial distribution is of great importance for diagnosing and evaluating the performance of laser system. Spatially sampling large size laser beam is the first step to measure the laser beam parameters, decreasing the influence on measurement result from the laser incident angle and sampling large size laser beam with high spatial resolution and high duty ratio are very critical for accurately measuring laser beam intensity temporal-spatial distribution. Base on the principle of diffuse scattering, which means the distribution of scattering light has nothing to do with incident light, scattering sampling and attenuating method was put forward in array detectors for the measurement of laser intensity distribution. The diffuse scattering principle was briefly introduced. The construction of sampling and attenuating was given, the transmission laser intensity computation model was set up, the intensity formula was deduced and verified through experiments. The applications of scattering sampling unites and photodiode array or CCD were introduced. There are notable advantages, high resolution which is 2 mm or so; high duty ratio which is up to 40%; wide use angle which can be up to 30 and adjustable multiple attenuation which wants. Scattering sampling and attenuating provide a new method for array detector to sample laser beam, which overcome the shortages of technologies available, improves the measuring ability and measuring accuracy significantly and is of great significance to laser intensity distribution measurement device, the method can be widely used to development the measurement systems of laser beam parameters.