It’s been four decades ever since Einstein’s activated radiation concept in 1917, namely, until 1958, that two American micro-wave scientists C.H. Townes and A. I. Schawlaw issued the famous thesis named “Infrared ray and optics activator? which had broken the ice and pointed out the possibility of emitting based on activated radiation, with realization of reversal of particle numbers as its prerequisite. At the same time, this thesis kindle the interest of many scientists working in optical area to propose different testing methods for actualize the reversal of particle numbers, as a result a brand new area—laser research was developed.

In the same year (1958), the scientists Basov and Prokhoro of USSR issued a thesis named “Proposition of realizing tri-energy reversion of particle number and semiconductor laser? in Sep. 1959, Townes came up with the suggestion of making ruby laser…… On May 15th, 1960, T.H. Maiman from Hughes lab, California developed the first ruby laser, which can create laser with a 694.3nm wavelength. Maiman is using ruby as light emitting material and the densely emitting material—impulse Xenon lampas as emitting source(as shown in fig.), he has eventually activated the first lasing light after hard work on it ever since the year 1957. Because of the outstanding contribution in the field, Townes, Basov and Prokhoro had shared the Nobel prize for Physics in 1964.

The first ruby laser of China is built in August 1961 at Changchun Optical Precision Machinery Institute, Chinese Academy of Sciencer (CAS). Compared to that of Maiman’s laser, this machine is advanced in structure design, though we lagged far behind the United States in industrious level then, and the researchers had to develop manually with own design under a quite difficult developing condition. From then on, we enjoyed a rapid development in laser technology, which has been widely used in various areas. In June 1987, a high power (1012W) impulse laser system was developed at Shanghai Optical Precision Machinery Institute, Chinese Academy of Sciencer (CAS), which serves a great contribution in China’s laser fusion study for many years.