What is a laser? A laser is a device that emits light through a process called optical amplification. An optical amplifier is a different device that amplifies a signal directly; it does not need to convert the signal to an electrical signal. Optical amplifiers are important in optical communication and laser physics. The word laser is an acronym for the phrase “light amplification by stimulated emission of radiation. Coherent light waves are light waves that are in phase with each other. This is how lasers differ from other types of light. Spatial coherence is the outputting of a narrow beam; they can be focused on tiny spots achieving a high irradiance or they can be launched into beams of low divergence in order to concentrate their power at a large distance. Spatial coherence allows a laser to be focused to a tight spot which allows laser cutting and lithography to be possible. Spatial coherence also allows the laser to stay tight and focused over long distances which enables laser pointers. Temporal coherence is a wave at a single frequency whose phase correlates over a large distance along a beam. A beam produced by a thermal source has an instantaneous amplitude. Lasers can contain high temporal coherence which allows a narrow spectrum and can only emit a single color of light. Most single wavelength lasers produce radiation in modes having slightly different frequencies. There are lasers that emit a broad spectrum of light simultaneously. There are some lasers that their light beams diverge more than required. However all these devices and methods are all classified as lasers based on their method of producing that light. Lasers are needed in situations where light of spatial or temporal coherence is necessary and they ... ... middle of paper ... ...ser diodes have a very wide range of uses that include, fiber optic communications, barcode readers, laser pointers, CD/DVD/Blu-ray reading, laser printing, scanning and increasingly directional lighting sources. Dye lasers use organic dye as the gain medium. The wide spectrum of available dyes allows these lasers to be highly tunable to produce very short-duration pulses. In their most prevalent form these solid state dye lasers use dye-doped polymers as laser media. Free-electron lasers generate coherent radiation, currently ranging in wavelength from microwaves, through soft X-rays. They have the widest frequency range of any laser type. While free electron laser beams share the same optical traits as other lasers its operation is very different. Unlike gas, liquid, or solid-state lasers free electron lasers use a relativistic electron beam as the lasing medium.
Glow sticks get their “glow” when two chemicals are mixed together because of a chemical reaction. The chemical reaction is called Chemiluminescence. A Typical glow stick has a plastic tube with a smaller inner tube inside. There are three components, two chemicals and a fluorescent dye which accepts the energy and helps covert to light. There is more than one way to make a glow stick, but the most common uses a solution of hydrogen peroxide and phenyl oxalate ester along with the fluorescent dye. The hydrogen peroxide is in its own compartment away from the other two components until ready to use. The fluorescent dye is what determines the subsequent color of the glow stick when the chemical solutions are combined.
Light sticks work in a similar way. When you “snap” a light stick, the chemical in the glass capsule mixes with a chemical in the plastic tube and creates light energy. Instead of the chemicals used by a firefly, other chemicals are used to create a glow. The light stick that you can buy at a store usually contains hydrogen peroxide, phenyl oxalate ester, and fluorescent dye (New York Times Company, 1 of 3). The light stick will glow the same color as the fluorescent dye placed in it. In luminescence, the chemical reaction “kicks an electron of an atom out of its ‘ground’ (lowest-energy) state into an ‘excited’ (higher-energy) state, then the electron give back the energy in the form of light so it can fall back to it’s ‘ground’ state (Fluorescent Mineral Society, 1 of 2).
For years law enforcement has been searching for more effective less lethal options to apprehend suspects. One of the newest technologies available is the Taser, also known by industry standards as an electronic controlled device (ECD). The Taser uses electricity to override the central nervous system, an effect referred to as “neuro-muscular incapacitation (NMI), to cause temporary incapacitation to allow officers to gain control of a subject.
Ultrasound is sound waves that have a frequency above human audible. (Ultrasound Physics and Instrument 111). With a shorter wavelength than audible sound, these waves can be directed into a narrow beam that is used in imaging soft tissues. As with audible sound waves, ultrasound waves must have a medium in which to travel and are subject to interference. In addition, much like light rays, they can be reflected, refracted, and focused.
Electromagnetic spectrum is a list of the most possible range of electromagnetic radiation around us. their many different electromagnetic radiation in the world. for example we got radio radiation, sun 's radiation , microwaves radiation, etc. many of ths radiation have different level of wavelength, energy, frequency, and also different classes. the way the electromagnetic spectrum works is by wavelength. the bigger the wave length the smaller power it have. the small wavelength is the most power it have. for example a radio tower, it haves a wavelength of the size of a football field. that wave meter is 105 and it frequency is 104. this is one of the longest wavelength in the electromagnetic. in the other hand Gamma Ray is one of the shortest wavelength in the electromagnetic but it hav...
There are many kinds of batteries which consist of different materials in order to produce an electric charge. Here are some of the most common batteries, what they consist of and how they work.
X-rays and gamma ray photons are part of the electromagnetic spectrum. The twin nature of electromagnetic radiation is used to justify the wave and its behavior. A photon is a bundle of energy that can be identified by the equation E = hv. Where h is the planks constant and v is the frequency. The frequency is equal to the speed of light 3x10 8 divided by the wavelength. Therefore, high-energy radiations have a short wavelength and a high frequency.
A spectrum is an image or distribution of colour of any electromagnetic radiation arranged in a progressive series according to wavelength.
As you can see lasers are a very useful and important tool which is why I have
In 1784, someone using a flintlock pistol shot Edward Culshaw. In those days, there were no bullets, as we know them. Gunpowder and a ball of lead were put into the gun’s muzzle and packed with paper wadding. A spark made when the gun’s hammer struck some flint at the back end of the barrel ignited the powder. When the constable examined Culshaw’s wound, he found a piece of newspaper used as wadding to pack the powder in the killer’s gun. The prime suspect in the killing was a man named John Toms. When a piece of newspaper found in Toms’ pocket was compared with the piece found in the wound, the pieces fit together like two pieces of a jigsaw puzzle. Based on the evidence, Toms was easily convicted. The Toms case was probably the first in America in which ballistics was used to solve a crime.
Spectroscopy basically involves the study of the interaction of radiated energy with matter. These different radiations could be used to study chemical and physical material properties of different atoms. Colors of light differ in wavelength and energies and when they interact with matter, the light is either scattered, reflected, transmitted, absorbed, reflected or fluorescence. The interaction makes vibrational, electronic or nuclear changes in energy levels. This difference between energy levels includes a range of electromagnetic spectrum. Types of electromagnetic radiation include gamma rays, x-rays, ultraviolet, visible, infrared, microwaves and radio wave. Energies, wavelengths, frequencies, or wave number can be used to describe the radiations.
Magnets are stones that produce magnetic fields. The magnetic field is invisible, but is responsible for the most noticeable aspect of a magnet: the attraction of a metal object or the repulsion of another magnet. Magnets are used in common everyday household items: credit cards, TVs, speakers, motors, and compasses. A magnets strength is measured by its magnetic moment. (“Magnetism”)
Technology in the military has greatly increased strength and eased the ranking among world powers and effected the development of new military weapons. The term “Survival of the fittest” means that the strong will succeed but the meek will not, this is the case with military technology. The U.S. has the best technology in the world, therefore we are the highest military power.
The effects of electricity control much of our daily lives. Many of our gadgets and everyday tasks are run by this wonderful source of power. For example without electricity we would not be able to make a cup of coffee in the mourning, or even make a long distance call to family or friends. There have been several technological breakthroughs by many brilliant people throughout history regarding electricity. It has come from being discovered as a small current to being transformed into useful power to run such things as computers. Ben Franklin, Guglielmo Marconi, Thomas Edison, Paul Nipkow, and Charles Babbage have all contributed to the advancement of electricity, and all of their advancements have supplied society in many ways.
The electromagnetic spectrum is a range of different types of radiations, this is energy that travels and spreads out as it goes. This range involves more than just visible light- small portion of the spectrum detected by the human eye- it goes beyond what the human eye cannot see. The two most important characteristics of the spectrum are wavelength and frequency. The electromagnetic spectrum can be divided into three different parts: the theory of visible light, the range of the electromagnetic spectrum, and how it benefits mankind.