Lasers
Table of Contents
Introduction...................................................3 History...........................................................4 The Structure................................................5 Uses..............................................................6 The Future.....................................................7 Glossary........................................................8 Cited Sources................................................9 About the Author..........................................10
Introduction A laser is a device that produces light by shooting out electromagnetic radiation. “Laser� stands for light amplification by stimulated emission of radiation.
History Maser and Laser In 1953, Charles Hard Townes and students produced the first microwave amplifier, which is a device that works in similar ways to the laser, but amplifying microwaves is more like an infrared laser than a visible one. Townes’ maser also cannot turn ON for a long time. ! At the same time at the soviet union, Nikolay Basov and Alexandr Prokhorov were working on the quantum oscillator that solved the problem of not being able to be turned ON for a long time, it done that by using more than two energy levels.
In 1957, Charles Hard Townes and Arthur Leonard started a serious research of a infrared laser. As they researched more, they didn’t use infrared radiation but focused on visible light which now is called a Laser.
The Structure Classes Class There are many classes of lasers, I, II, IIIa, etc. Some lasers can’t hurt you, but some can. For example: a military laser is in class IV. There are also classes like 1, 2, 3b, and more. These are the newer class classifications.
Danger
Used
Power
I
No danger possible even if stared for hours
Used in DVD players and others
Not strong enough to do harm
II
No damage unless stared for a extended time
Used in most laser pointers
1 mW
IIa
Damage to the eye if looked at for 1,000 sec to burn retina
Used in commercial laser scanners
Lower powered end for the second class
IIIa
Mostly dangerous in combination of optical instruments
Sights for firearms and many laser pointers
>5 mW
IIIb
Damages the eye in 1/100th of a second
Used in a lot laser pointers
5-500mW
IV
Damages the eye or skin immediately
Used in military, medical, industrial, and now many laser pointers
<500mW
A graph for each class of laser
Uses Uses in Present Lasers are important to us, they are in everyday technology. They are in DVD players, laser printers, and barcode scanners. In the hospital they are in laser surgery, in military uses, they are in targeting devices, measuring distance and speed, and lots more uses for lasers.
Lasers are also used in movies with lasers and holograms. Sometimes, lasers are used to destroy or break things, they are in DVD/CD burners and more. The lasers are sometimes just for fun we can buy them as lasers pointers and other equipment. We can point stars, burn paper, pop balloons, and lots more uses for lasers.
The Future Uses in the Future Although our uses with the lasers is already very smart, in the future there may be very high-tech uses. But sometimes, as the lasers are good for helping us, the lasers also have a bad side, because if we can have it in our everyday lives, bad people can also use it.
As people get smarter, the technology will improve. Maybe in the future, there may be laser guns, light sabers, who knows? Maybe in the future there is a laser that can find an object in a black hole. There may be many possibilities but nobody knows.
Glossary Electromagnetic radiation-a type of radiation. Infrared-a type of light that is not visible to the human eye Microwave-a type of radiation Radiation-the emission of energy as electromagnetic waves.
Cited Sources Wikipeda, . N.p.. Web. 12 Jan 2014. <http://en.wikipedia.org/>. . N.p.. Web. 13 Jan 2014. <http://photonics.usask.ca/photos/>. Helmenstine, A. M.. N.p.. Web. 13 Jan 2014. <http:// chemistry.about.com/>. Jelsoft Enterprises, . N.p.. Web. 14 Jan 2014. <http:// laserpointerforums.com/>.
About the Author
I am 10 years old and likes science and technology projects, I am a person that likes origami and doing crafts. I have an interest in making things that takes time and is hard. For example I would be happy to make a rail gun which is a gun that uses electricity to shoot.
Do you want to learn more about lasers? Did you know that a laser are used in a hospital? If you donâ&#x20AC;&#x2122;t, then you should get at least a glimpse of this book.