LasersBy: Ashley Dansby & Rebecca Bryant

Preview or Table of Contents

• Objectives• Introductory• Laser Acronym• How Lasers Work• Properties of Laser

Lighto Monochromatico Coherento Directional or

Collimated

• Advantages in Certain Applications○ Barcode Scanners○ Communications○ Surveying○ Welding and Cutting○ Lasik Eye Surgery○ Medical○ Medical Disadvantages○ Dentistry

● Demonstration● Bibliography

Objectives

• Describe the Properties of Laser Light

• Explain how Laser Light has particular advantages in certain applications

Introductory

• In this lesson we will be talking about the three properties of laser light and the advantages of laser light in certain situations.

LASER Acronym

• Light• Amplification by• Stimulated • Emissions of• Radiation

How Does a Laser Work?

Laser Light Properties

1. Monochromatic

2. Coherent

3. Directional or Collimated

Monochromatic

• One specific wavelength or one specific color

• Other light is a combination of many wavelengths or colors.

Coherent

• Organized Photon Emission

• Laser light is in phase with space and time.

• Unidirectional - all together

• Each photon moves in step with the others. All of the photons have wavefronts that launch in unison.

Directional or Collimated

• Tight, narrow beam of light in a certain direction from the source.

• Parallel light waves

• Other lights come from multiple direction from the source. o Examples: Light Bulbs, Sun

Picture

Bar Code Scanners

• Supermarkets and stores use lasers to scan the barcode to identify the universal product.

• The advantage of the laser is that you don’t have to look each individual item up.

Communications

• A significant advantage of lasers is that it is monochromatic, which allows the pulse shape to be maintained over a large distance.

• With the better pulse, the communication can be sent at a fast rate without a disruption in the pulses, this is the advantage.

Surveying

• When surveying an area, a fast laser pulse is sent to a corner reflector at the point to be measured to get the distance.

• Since the laser is directional and monochromatic, it is an advantage for surveying.

Welding and Cutting

• On auto assembly lines, a carbon dioxide laser helps with computer controlled welding.

• Lasers also make the impossible task of welding stainless steel handles to copper cooking pots.

LASIK Eye Surgery

• The Surgery is performed by using a laser, and LASIK surgery correct vision problems.

Medical

• Lasers are more precise than scalpels. Tissue near an incision is protected, since there is little contact with surrounding skin or other tissue.

• The heat produced by lasers sterilizes the surgery site, thus reducing the risk of infection.

• Less operating time may be needed because the precision of the laser allows for a smaller incision.

Medical (cont)

• Healing time is often shortened; since laser heat seals blood vessels, there is less bleeding, swelling, or scarring.

• More procedures may be done on an outpatient basis.

• Lasers can be used in two ways to treat cancer: by shrinking or destroying a tumor with heat, or by activating a chemical.

• Lasers may be used with endoscopes, tubes that allow physicians to see into certain areas of the body, such as the bladder.

Medical Disadvantages

• Relatively few surgeons are trained in laser use.

• Laser equipment is expensive and bulky compared with the usual surgical tools, such as scalpels.

• Strict safety precautions must be observed in the operating room. (For example, the surgical team and the patient must use eye protection.)

Dentistry

• Sensitivity Is detected On time

• Cavities Filling Became Simple

• Tooth Whitening

• Less And Sometimes No Blood Loss

• Effective Treatment Of TMJ dental disorder

Demonstration

Plastic Bottle Beam

• Fill up a plastic water bottle with water and add a sprinkle of cornstarch. Turn down the lights and turn up the laser, aiming the beam through the bottle.

• Do you see the original beam in the bottle? • Can you find the reflection beam and the pass-

through beam?

Bibliography

• Wescheler, M. (2000, April 1). How Lasers Work. HowStuffWorks. Retrieved October 28, 2013, from http://science.howstuffworks.com/laser.htm

• TinyPlanetsBlog. (2010, December 27). TinyPlanetsBlog. Retrieved October 28, 2013, from http://tinyplanetsblog.com/science/two-cool-laser-experiments-you-can-do-with-your-kids

• Nave, R. (n.d.). Laser Applications. Laser Applications. Retrieved October 28, 2013, from http://hyperphysics.phy-astr.gsu.edu/hbase/optmod/lasapp.html

• Kohler, C. (2013, April 30). Top 5 Major Advantages Of Laser Dentistry. Examiner.com. Retrieved October 28, 2013, from http://www.examiner.com/article/top-5-major-advantages-of-laser-dentistry

• Harris, W., & Fruedenrich, C. (2000, July 10). How Light Works. HowStuffWorks. Retrieved October 28, 2013, from http://science.howstuffworks.com/light10.htm