100 Greatest Science Inventions of All Time

By Kendall Haven | Go to book overview

Laser
Year of Invention: 1957

What Is It? A machine that produces a high-energy light beam at the same ex-
act frequency.

Who Invented It? Gordon Gould (in Long Island, New York)


Why Is This Invention One of the 100 Greatest?

Supermarket checkouts rely on laser beams to scan your purchases. So do almost all retail stores in the Western world. Many eye surgeries are routinely performed using lasers. Communication systems pack thousands of voice channels on laser beam carriers. Engineers and construction crews make extensive use of lasers. Lasers read compact disks. They manufacture surgical cutting tools. There are few aspects of modern life that are not touched by lasers.


History of the Invention

What Did People Do Before?

Lasers were not a direct replacement for any previously existing technology. People managed without. Checkout clerks punched codes and amounts into cash registers by hand. Levels and lines of sight were checked with light scopes and human eyes. Knives held by human hands performed cutting.


How Was the Laser Invented?

Charles Townes first created the theory and idea that led to lasers. He was struck with a powerful vision during a midnight stroll in the spring of 1951 while attending a Washington, D.C., conference called by the Office of Naval Intelligence. Conference attendees were searching for a way to generate higher frequency (shorter wavelength) radio signals. He couldn’t sleep and decided a midnight wander might clear his head. Sitting on a park bench, he realized that, if they were ever going to produce signals with microscopically small wavelengths, then instead of using bulky vacuum tubes, they would have to use atoms (the smallest device known) to produce those wavelengths. That idea led to lasers.

In 1917 Albert Einstein predicted that stimulated atoms would emit photons—particles of light energy. Townes decided to use blasts of microwave radiation to stimulate atoms into emitting streams of photons. Townes called his 1953 creation a maser (Microwave

-267-

Notes for this page

Add a new note
If you are trying to select text to create highlights or citations, remember that you must now click or tap on the first word, and then click or tap on the last word.
One moment ...
Default project is now your active project.
Project items

Items saved from this book

This book has been saved
Highlights (0)
Some of your highlights are legacy items.

Highlights saved before July 30, 2012 will not be displayed on their respective source pages.

You can easily re-create the highlights by opening the book page or article, selecting the text, and clicking “Highlight.”

Citations (0)
Some of your citations are legacy items.

Any citation created before July 30, 2012 will labeled as a “Cited page.” New citations will be saved as cited passages, pages or articles.

We also added the ability to view new citations from your projects or the book or article where you created them.

Notes (0)
Bookmarks (0)

You have no saved items from this book

Project items include:
  • Saved book/article
  • Highlights
  • Quotes/citations
  • Notes
  • Bookmarks
Notes
Cite this page

Cited page

Style
Citations are available only to our active members.
Sign up now to cite pages or passages in MLA, APA and Chicago citation styles.

(Einhorn, 1992, p. 25)

(Einhorn 25)

1

1. Lois J. Einhorn, Abraham Lincoln, the Orator: Penetrating the Lincoln Legend (Westport, CT: Greenwood Press, 1992), 25, http://www.questia.com/read/27419298.

Cited page

Bookmark this page
100 Greatest Science Inventions of All Time
Table of contents

Table of contents

Settings

Settings

Typeface
Text size Smaller Larger Reset View mode
Search within

Search within this book

Look up

Look up a word

  • Dictionary
  • Thesaurus
Please submit a word or phrase above.
Print this page

Print this page

Why can't I print more than one page at a time?

Full screen
/ 336

matching results for page

Cited passage

Style
Citations are available only to our active members.
Sign up now to cite pages or passages in MLA, APA and Chicago citation styles.

"Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn, 1992, p. 25).

"Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn 25)

"Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences."1

1. Lois J. Einhorn, Abraham Lincoln, the Orator: Penetrating the Lincoln Legend (Westport, CT: Greenwood Press, 1992), 25, http://www.questia.com/read/27419298.

Cited passage

Welcome to the new Questia Reader

The Questia Reader has been updated to provide you with an even better online reading experience.  It is now 100% Responsive, which means you can read our books and articles on any sized device you wish.  All of your favorite tools like notes, highlights, and citations are still here, but the way you select text has been updated to be easier to use, especially on touchscreen devices.  Here's how:

1. Click or tap the first word you want to select.
2. Click or tap the last word you want to select.

OK, got it!

Thanks for trying Questia!

Please continue trying out our research tools, but please note, full functionality is available only to our active members.

Your work will be lost once you leave this Web page.

For full access in an ad-free environment, sign up now for a FREE, 1-day trial.

Already a member? Log in now.