One day in 1960 something happened that seemed almost magical to many people. Dr. Theodore Maiman put operation a device that gave off a thin, bright red beam of light. This remarkable device was the world’s first laser. It was called a ruby laser because Maiman passed ordinary light through a ruby to produce the laser light. Since that day hundreds of different kinds of lasers have been made, and thousands of practical uses have been found for these modern “supertools.”
Until the invention of the laser, using powerful beams of light was an idea that appeared mainly in science fiction. The first important example was in H.G. Wells’s classic The War of the Worlds (published in 1898). In the novel sinister Martians use a terrifying heat ray to attack the earth. Later, in the early comic strips, space heroes like Flash Gordon and Buck Rogers used deadly ray guns to fight their archenemies. Certainly, most people today are familiar with the exploits of Captains Kirk, Picard, Janeway, and Archer of the Starships Enterprise and Voyager. Fans of the Star Trek TV shows and movies know all about phasers and photon torpedoes, those fabulous, futuristic weapons of light. Equally famous are the light swords wielded by Luke Skywalker, Darth Vader, and other characters in the popular Star Wars films.
Of course all the devices mentioned above are destructive. This can be misleading, for science fiction is filled with examples of light being used for constructive purposes as well. For instance Star Trek’s characters use a small light source to perform operations, and they use beams of light to take apart thick metal walls, to repair broken circuits, and to generate holograms to create realistic virtual environments on the “holodeck.”
Such advanced technology does not utilize normal everyday light, of course. It requires laser light, which is very different from ordinary natural light. The laser produces light that has been amplified, that is, made considerably brighter and more powerful. It took human beings, in their never ending search for new knowledge, to go beyond mere light, to invent the laser, and to take advantage of its marvelous properties. Just as Captains Kirk and Janeway go “where no one has gone before,” scientists saw a light no one had seen before and put it to use for the good of all people.
Indeed, on that day in 1960 when the ruby laser began to glow, a new era began for humanity. The light no one had ever seen suddenly began to change science fiction into science fact. As lasers continue to advance rapidly and do more tasks in a wide range of scientific, medical, industrial, and commercial areas, it seems more and more likely that the society depicted in the world of Star Trek may be much closer than most people imagine.
A laser is a device that produces an unusually powerful beam of light that does not exist on its own in nature. Today this light is used to perform thousands of useful tasks. A laser can give off a light beam that blasts through a thick metal wall or bores a hole in a diamond. Some lasers can measure things seen only under a microscope or even perform delicate eye operations. Every day, lasers are used in communications, factories, hospitals, and various entertainment media. In fact, lasers make our lives better and easier in so many ways that scientists have come to refer to these devices as the supertools of the modern age.
The invention of the laser was the result of many ideas and discoveries, each building upon the ones that came before it, going back more than a hundred years. Scientists did not purposely set out to invent the laser; in fact, no one seriously considered such a device until just a few years before the first laser was built. Most of the ideas that led to its invention were the results of attempts by scientists to learn more about light and how it behaves. As time went on, the idea that light might be made more powerful, or amplified, became more important to scientists. Only when a few researchers managed to put all these accumulated ideas together in a very special way did it occur to them that something like a laser could be built.
Use of LASER in Astronomy, Geography, and Surveying
One of the most important scientific uses for lasers is that of an advanced measuring tool. The potential of these devices to give precise figures for very long distances was shown in 1969 when the Apollo 11 astronauts became the first men ever to walk on the moon. Before blasting off on their return flight they left behind a bizarre-looking mirror. A short time later scientists on Earth claimed that the strange mirror had revealed to them the distance from Earth to the moon, a figure that was accurate to within the length of a person’s finger. This moon mirror was neither mysterious nor magical, though it would have seemed so to many people only a few years before. In reality, National Aeronautics and Space Administration (NASA) scientists had instructed the astronauts on exactly how to position the mirror as part of a plan to measure the Earth-to-moon distance with a laser beam.