(Awake in the winter months XVI), December 18, 1994, China's first optical rain gauge to come out.

1994 12 18, China's first optical rain gauge has appeared in Beijing and by experts. Relevant experts believe that this achievement to reach the international advanced level. Developed by the Seventh Research Institute of the Air Force, this optical rain gauge, the beam passes through rainfall area, the ups and downs of the statistical properties of the scattered light receiver to remote sensing rainfall parameters.