How Many Do You Have?
In the 1940’s, there was a game in which you would ask someone how many motors they thought they had in their home. The estimates were almost always much too low, as you could point out by reminding them that there were motors in such things as their wall clocks, their refrigerators, their record players, and their wristwatches.
Today, you could play the same game by asking someone how many microprocessors they think they have1. And soon, there will be another good topic for the game.>
And the laser has now moved into the home: Do you have a CD player? A DVD player? A computer with a CD-ROM drive? All of those contain lasers. In fact, without the laser there could be none of the CDs or DVDs that bring us so much music and movies, and that store so much of our data. “Mainframe ” and large office computer printers have used lasers for more than a decade, and the prices of smaller laser printers have now come down far enough to be attractive to home office users.>
The hologram is an outgrowth of laser technology. Holography, too, had no practical use initially. In fact, it was referred to as “a solution looking for a problem”. Well, like the laser it has found many problems to solve; now not only does holography have industrial applications, it is probably even in your purse or wallet: If you have a credit card, take it out and look at it. There is most likely a small area of the card that changes colors as you reorient it in your hand. That is a hologram. It makes the credit card difficult to counterfeit, and it would not be possible without the laser.
2. When mathematicians decided that negative numbers can be said to have square roots, they called the resulting numbers “imaginary numbers” and were convinced that imaginary numbers were of purely abstract significance. To their horror, they saw practical uses developed in several branches of engineering and science.
3. Sometimes the eventual uses of theoretical discoveries cannot even be conceived of at first. For instance, when the military developed a network to facilitate efficient exchange of data among scientists at major universities, they could not have anticipated that someday it would grow into the Internet and be used by a major portion of the world’s population.4. One of the envisioned achievements that has not yet been accomplished is virtually instantaneous signal processing.. >
W. A. Shapiro