Curious who invented the laser? While one source may be credited with the invention of the laser, the technology that goes into lasers has involved the work of many.
Albert Einstein theorized about the possibility of a laser.
In 1917, long before laser technology existed, Albert Einstein theorized the possibility of a laser. Einstein explored the process whereby lasers are possible, which he called "Stimulated Emission." Einstein's exploration of this process laid the groundwork for later laser technology development.
The maser predates the laser.
The maser, or microwave amplification by stimulated emission of radiation, was developed by Arthur Schawlow and Charles Townes in 1954. The maser used microwave radiation and ammonia gas in a manner very similar to the laser. While the technology is close, the maser doesn't use visible light, so it's a step away from the optical laser.
Laser technology was theorized by maser inventors.
Townes and Schawlow went on to patent the maser and even published papers about the possibility of a visible light laser. In the papers, Townes and Schawlow theorized that a laser was possible using infrared or visible light. However, they never pursued laser technology.
Theodore Maiman or Gordon Gould?
From here, the next step is the actual development of an optical laser. However, historians argue about who should get the credit for the first optical laser. Theodore Maiman invented a ruby laser in 1960. Gordon Gould began work on an optical laser in 1958, but he failed to file a patent until 1959, and the patent was refused. Credit for the first real optical laser belongs with one of the two men, but the truth may be forever obscured by a technicality.
The gas laser.
In 1960, Ali Javan invented the gas laser. The first gas laser used helium neon gas to convert electrical energy to light output. Javan's gas laser found many applications in both scientific and technological arenas.
The semiconductor injection laser.
Robert Hall was the next person to come along with a laser technology breakthrough. He created the semiconductor injection laser in 1962, which is still used today in types of technology and electronics.
The carbon dioxide laser.
1964 saw another laser development, when Kumar Patel created the carbon dioxide laser. The carbon dioxide laser is still used in medical laser surgery today.
The Excimer laser for eye surgery.
The laser that ophthalmologists use for laser eye surgery is the Excimer laser. Doctor Stephen Trokel holds the patent on the Excimer laser, which relies on technology previously used by IBM to etch silicone computer chips in the 1970s. The Excimer laser was approved for use in the United States in 1995.
The evolution of laser pointers.
As laser technology has improved, laser pointers have evolved, too. The infrared laser pointer has been around for years since infrared laser technology isn't new. Green laser pointers have been around for only the past five or six years, and blue laser diodes are even newer. Expect lasers to continue to evolve as laser technology improves.