Transcript Lasers - repetto5.com

Lasers
By: Garrett Sakomizu
Introduction to the World of Lasers
Imagine yourself in a supermarket and you are ready to go pay for your items. You go home and
watch a movie in your DVD player. You would have needed a laser for both of those tasks. Lasers
are important tool in our everyday lives and is applied to more and more everyday things as
technology becomes more and more advanced. In this presentation I have given information on
lasers in a couple of ways: science about lasers, the parts of the laser, how a laser works, lasers in
our modern world, and lasers in movies and myths.
I hope that you, as the audience will enjoy my presentation.
The Science Behind Lasers
The word LASER is an acronym for “Light Amplification by Stimulated Emission of
Radiation.” Lasers are very unique compared to flashlights as you can see in this picture:
One Color
Multiple Colors
In these pictures, the flashlight’s wavelengths are different because the flashlight emits white light
(which is composed of red, orange, yellow, green, blue, indigo, and violet) which have different
wavelengths. In a laser, the wavelengths are the same, which, in turn, makes a laser one color.
This is why lasers are coherent; they are all one color.
Light
Amplification by
Stimulated
Emission of
Radiation
What Are The Parts of a Laser and How Do They Work?
As this presentation has showed you, lasers are powerful beams of coherent light. So, a laser must
have something to do with heat or electricity. The diagram below shows the parts of a laser and
how they work:
6. Mirrors at
either end bounce
the photons
back and forth
7. The mirror
3. Electrons absorb that is not
entirely reflective
the energy from
allows some of
the flashtubes’
the light to
electricity
leave the tube
as a tight beam
of laser light
1.
1.
excites
the
electrons
from
the
atoms
in the
gain
medium
2. Electricity
is produced
4. Electrons
release the
energy in
the form
of a photon
5. The photon
bangs into
another electron,
causing it to
release another
photon
Lasers in our Modern World
Like this presentation has said before, lasers are used all over the place in modern technology. The
below photographs show that lasers are used in/for:
Bar Code Scanning Devices
An eye treatment such as LASIK
Playing DVD’s and CD’s
Welding (cutting through metal)
…and so
much more…
Lasers in movies and in myths
Lasers have been used in some movies and myths. Here are three examples:
In the last scene of the movie Real Genius Jerry’s
house is destroyed when an overhead plane fires
a powerful laser at an enormous bag of popcorn,
cooking it, and crumpling the house to the ground.
Here is a photograph of that scene:
Lasers have also been used in movies for fighting.
Consider the movies Star Wars and Star Trek. In
Star Wars, lasers are used in lightsabers and
blasters. Here is a photo of a lightsaber:
Lasers are also used in Star Trek
vehicles weapons such as in phasers.
The myth is that a strong enough laser can cook so
much popcorn that it can break through windows
and doors and crumple the house to the ground.
The End
I hope you enjoyed my presentation.