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.