Today, 31 years ago, on December 18, 1994 (Lunar Calendar November 16, 1994), China's first optical rain meter was introduced. On December 18, 1994, China's first optical rain meter was introduced in Beijing and approved by experts. Experts believe that this achievement reached an international advanced level. This optical rain meter developed by the Seventh Air Force Institute uses light beams to pass through the rain zone and generate the statistical characteristics of oscillating dispersed light on the receiver to remotely sense the rain parameters.