LASERS Michael Cody Keith slack - PowerPoint Presentation

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LASERS

Michael Cody

Keith slack

Bianca

Cilento

What is a laser?

A laser is a device that emits light through the process of stimulated emission. LASER is actually an acronym for Light Amplification by the Stimulated Emission of Radiation. 

Stimulated Emission is

the process of an incoming photon reacting with an excited electron and making it to drop to a lower energy level. When the electron drops to a lower level, light is produced. 

Lasers come in many different forms; there are lower power laser points that are basically colored light and they range all the way up to high power lasers that have applications in geology, astronomy, and physics. 

Light that comes out of a laser is a narrow beam. 

This image shows the visible

light spectrum of an excited neon atom.  This is what the photon reacts with to create the laser light. 

Optics Involved

Optics is the study of light and its behaviors and interactions. Lasers are light beams cause by stimulated emission and photons reacting. Since lasers are light, they have the same properties. When the light enters a new medium with a different density, the light bends. This property is called refraction and can be seen in the image below. Lasers can also reflect off of surfaces; in the diagram below there is total internal reflection happening as the light bounces off the surface between the water and the air and back into the water. 

There is no dispersion in a laser, since a laser is only one color. Since there is only one frequency and one wavelength, it would not be able to split like white light does. 

This image shows a laser in water. The difference in medium is causing the light produced by the laser to bend. There is total internal reflection happening since no light is coming out of the water.  And it is refracting coming out of the water. 

How It's Made

In its simplest form, a laser is a tube that concentrates light over and over again until it emerges into a really powerful beam.A laser pointer is made of It consists of a laser diode, a circuit board, a case, and optics. The three main parts a laser is made up of an energy, a laser medium, and two or more mirrors that form an optical resonator

Lasers require gain mediums, a way to energize it, and a way to provide optical feedback. in order to produce light. Gain Medium: A material with the ability to amplify the light of a specific wavelength through stimulated emission. (The power of the light increases). 

The most common form of optical feedback is a pair of mirrors on either end of the gain medium, this is called optical cavity. 

How it's Made (Cont'd)The first laser was built in 1960 by Theodore H. Maiman at Hughes Research Laboratories, based on theoretical work by Charles Hard Townes and Arthur Leonard Schawlow.

How lasers work in theory

Most lasers contain other elements

that are used to change the properties of the light such as polarization, wavelength, and shape.

Uses and How it's Used

Lasers have applications in:Making hologramsMedicine/Surgery - Carbon Dioxide LasersDestroying Cancer cellsReconstructive eye surgery/Sealing the retina

Computer devices – laser mice, pointers, CD ROMS, DVD ROMSWar Machines – tanks, guns  Robotics, Image Processing, and Calculating distancesLaser cutters – cutting industrial metals

Hair and Tattoo Removal Optics labs – showing different properties of lightToys and laser pointers 

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This is an example of a Carbon Dioxide laser. They are used in many surgeries over scalpels because they are more precise. 

Resources UsedLasers, World of Invention (2006). Science in Context. 

How lasers work in theory (2011). Minute Physics. Laser Diagram. Quora. How a Laser Pointer is Made. Made HowWhat are Lasers Used For. WiseGeek. 

Cat Playing with Laser Pointer. Shaunspradlin.