History of Lasers
Lasers have been hailed as one of the great inventions of the twentieth century, following nuclear power, computers, and semiconductors, and have brought about a great technological breakthrough for mankind. The laser radiation produced by lasers is famous for being the "fastest blade", the "most accurate ruler" and the "brightest light". Nowadays, laser technology plays an important role in many fields such as medicine, the military industry, communications, and so on. The birth of the laser is the result of the tireless efforts and arduous exploration of many scientists. In 1917, Albert Einstein proposed the concept of "stimulated radiation", which laid the cornerstone for the theoretical foundation of lasers. Although the theory of lasers had already been proposed at that time, the actual preparation of lasers was quite challenging. By the 1950s, with the progress of photon and microwave technology, the manufacture of an oscillator cap...