Grade 10 Academic Science – Optics Laser Wars The word LASER is the acronym for Light Amplification by Stimulated Emission of Radiation. A laser is a special source of light of only one pure colour (or WAVELENGTH) or monochromatic. You cannot break up laser light into other colours. Moreover, a laser is an optical light source that emits a concentrated beam of photons. The beam stays together. Thus, the beam stays together over a long distance and can be focused on a very small spot. Diffract the Laser A laser is only one wavelength of colour; yet, it is still a very narrow beam of many rays. Can the rays be diffracted (i.e., eliminate or alter part of the beam)? If you shine the laser through a fine mesh or a bird's feather and onto a white wall, you may be able to create interesting patterns. A laser beam can be described as an array of almost perfectly synchronized waves. When you split the beams, you interfere with that synchronization. As a result, some waves will reinforce each other and some will neutralize each other waves. This action creates mesmerizing geometrical patterns. Aim your laser at a frosted incandescent light bulb. The bulb will glow and have several internal reflections. How do your polarized sunglasses work? Using two polarized sunglass lenses (…just use two pairs of sunglasses), place both lenses in the laser beam. Rotate one sunglass 90O. The lenses should block the light completely in one configuration and allow it to pass-through the other way. Laser Maze Work your laser beam around a maze using mirrors and lenses. INTERESTING TIDBIT A new light tool called "driver defeat or Laser Dazzler" is being developed to help soldiers slow approaching cars from a distance so they can determine if the driver is friend or foe. It works using laser. When a laser is pointed at the eye, the flashes create an "after-image," an optical illusion that limits a person's sight for a very short time. It' will be a little like driving into the sun. That is, a driver’s natural reaction while driving and experiencing glare is to either slow down or stop (source National Defense Education Program. http://www.ndep.us/laser-dazzlers ). Who would have thought -- lol.