The Laser: Still Beaming at 50

Like all modern inventions that have revolutionized the world of entertainment, science, technology and medicine, the birth of laser is of great consequence. The invention celebrated its half century on May 16 this year, for it was exactly 50 years ago when Theodore Maiman demonstrated the first functional laser by switching on a gadget at Hughes Research Laboratories and watched as pulses of pink hued light sprang from ruby crystals.

Although it seems straight out of a comic book—since we mostly see lasers in them or in science fiction movies—the laser has become a very important part of our lives. For example, the internet, which we all rely on for communication, depends on lasers which help carry data across—countries and continents—on fibre optic cables. At the supermarket, it helps cashiers process our shopping faster, and in our living rooms it helps play our CDs and DVDs. Cancer patients owe the laser their lives since it helps in treating the disease and other ailments.

The story of the laser is similar to the one of the integrated circuit. It began with Albert Einstein’s theory of stimulated emission, in which basically a photon interacts and excites an atom which then emits or projects an identical photon. This theory was put to the test in 1953 by US Physicist Charles Townes who developed a ‘Maser’ (Microwave amplification by stimulated emission of radiation). This used microwaves to excite atoms, although it wasn’t exactly the laser. Townes then used visible light instead of microwaves and the acronym of Laser was born (light replaced microwave).

When the invention was announced, newspapers excitedly displayed headlines bearing that ‘death ray’ from science fiction movies was here. One couldn’t blame them; it was after all the height of the Cold War where the Soviets were constantly defeating the US on many technological platforms. But the first laser mean was developed at Bell Laborites in 1960 and, since then, more than 10 Nobel Prizes have been awarded for its research and development. The world owes this technology a great deal, so much so, that in fact when man went to the moon in 1969 he placed a mirror on its surface so that lasers from the Earth could be shot on it so that time could be measured. Laser also helps us to track and measure the distance and orbit of the moon.

But perhaps the laser’s biggest contribution lies in its use in computer technology. The top-of-the-line laser research revolves around ‘femtosecond’ lasers which are used to provide denser storage on computer hard drives. In fact, prototypes and initial lasers of these kinds have increased hard disk performances by up to 100,000 times.

From science fiction to reality, we continue to discover the true potential of lasers that will help us progress further. Fortunately—and hopefully—the laser weapons that we see in comics and geeky movies are still years away.

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