Ever wondered how lasers function

in #stemng6 years ago

I was at the mall a few days ago and after purchasing all the items on my long list in a major store, I joined the queue to make payment. Fortunately for me the queue was not so long that day, so I got to the cashier and made my payment and was on my way home in a jiffy.

But then it suddenly occurred to me, what would have happened if there was no barcode scanner in the store. I wondered how much time I would have wasted if I had to wait for the cashier in charge to carefully and manually check for the cost of each item I purchased before going ahead to calculate the overall cost of my entire purchase.

How often do you think mistakes would occur and how long would Queues at major stores be like? You would agree with me that queues would be so crazy especially in this fast paced economy we live in today.

A Barcode scanner is simply just one of the numerous application of laser technology, with this technology in place the cashier simply picks up each item and scans the printed barcode using the barcode scanner and the computer automatically show the price of each item in a split second. This simple application of laser technology makes life so much faster.


Today I want you to Sit back and relax while I show you what laser technology truly entails


While growing up I loved watching science fiction movies such as starwars and for a very long time I erroneously associated Lasers strictly with state of the art futuristic warfare, however overtime I got to know that the application of this technology is quite vast and we actually make use of them in various equipment we utilize daily such as laser printers, DVD players, cutting equipment amongst others.

In recent times laser technology have continuously played a huge role for medical purposes because of the swift precision it offers. It is a major part of Equipment used for blasting tumors, eye surgery, fixing detached retinas, dental drills and also for tattoo removal. Just like Every other technological advancement the military is one of the Largest users of laser technology. They utilize laser technology to facilitate precision in numerous equipment. For instance, using Laser guided missiles and weapons are more effective and precise than an ordinary conventional missile of weapon.

Speed as well as Accuracy is extremely important when clothes are being manufactured in bulk, to facilitate the process of cutting fabrics, laser technology is employed using laser guided robots to cut numerous fabrics at the same time, this ultimately saves times and eliminates human error thereby boosting productivity. Large industries also effectively utilize the use of laser beams for cutting through metals as a result of the precision, easy automation and the elimination of sharpening of the equipment.


Let’s take a deeper look at lasers


Laser (Light Amplification by stimulated Emission of Radiation) simply creates concentrated light beam by effectively controlling the rate at which energized atoms ultimately release photons. This is achieved by atoms pumping out trillions of light particles known as photons at the same time, these light particles are then channeled so they get very concentrated in the desired direction.

The light produced by Lasers have specific frequency as well as a specific wavelength which make them effectively useful as a result of the precise beam of energy they produce. The monochromatic light produced are tighter and narrower which makes them directional, concentrated and strong, thereby making them so powerful.
One unique feature of a laser is the fact that stimulated emission occurs and this facilitates the organization and coherence of waves, if you take a close look at the wave form of a laser you would realize that each photon has a crest that lines in unison with the crest of other waves.

Basically there are numerous types of lasers with widely different functions but ultimately for a laser to function effectively the atoms has to be excited. There are two main parts required for a laser to achieve this regardless of its application, these parts are the lasing medium and a tool to Stimulate the atoms.

Ultimately the wide variety of atoms that exist can be stimulated to get them to an excited state using different techniques, so this brings about the 5 main kinds of lasers which are Gas lasers, fiber lasers, solid state lasers, semiconductor lasers and the liquid dye lasers. Amongst this type of lasers semiconductors lasers are the cheapest and tiniest as they can be used in small equipment such as barcode scanner and printers, especially when they are compared with the expensive and large nature of the gas, liquid and solid lasers which are more powerful.

Typically, the lasing medium that contain the atoms are pumped with electrical discharges, this action would get some atoms to change state to about 2-3 levels above their initial ground state and they become excited. Ultimately a swift difference occurs in the lasing medium because the number of atoms that are excited continuously gets increased and as a result there is a corresponding increase in the degree of population inversion.

Basically for an electron to jump to an excited state, it has to absorb a certain amount of energy to archive this, so the typical difference between the electrons in excited state and ground state is as a result of the energy absorbed. The same way these electrons absorb the energy they also release the energy as photons, which is a kind of light energy. These photons that are released have wavelengths that differ depending on the state and type of atoms, however identical photons could be released by a pair of atoms that are in the same state and are identical.

Within the atom in the lasing medium absorption continuously occurs, such that as electrons change state from a higher energy level the atoms absorb energy but as soon as the electron changes state back to their initial state after some milliseconds the atoms release the energy as a photon of light. As the process of absorption continues within the medium stimulated emission also takes place alongside, this occurrence takes place when photons stimulate an atom that is in an excited state prior to the time of impact, so as the impact happens the atom in excited state emits a photon that has the same specific direction and frequency of the photon that made contact with it. So eventually the initial photon has created another similar photon thereby making them two. This continuous process of stimulated emission within the medium eventually amplifies the light because the photons would increase considerably.

A major component of the laser medium are the pair of mirrors utilized to facilitate the effective to and fro movement of the photons within the medium. The arrangement of the mirrors is such that one mirror is located at one side of the laser tube and another mirror is located at the other side but this time around the mirror is a partial mirror. As reflection occurs as a result of the mirror put in place within the laser medium photons travel to and fro and they continuously stimulate electrons to change state and emit photons of similar phase and wavelength. So as this goes on in a very short while numerous photons of the similar wavelength and the same phase would have been produced thereby creating a cascade effect.

The partial mirror put in place is ultimately responsible for facilitating the formation of the concentrated beam of light. So as the photons travel to and fro within the medium some photons would get bounced back by the partial mirror but then some of the photons would escape through the partial mirror. This escaping photons would then go ahead to form a very powerful concentrated beam which could be used for various purpose.

Finally, Lasers are superb and amazingly powerful beam of energy which are very useful, some Lasers do not emit radiations that could be dangerous to humans while very powerful laser emit high level of radiation that are quite dangerous.


REFERENCES


Lasers

Encyclopedia of Laser Physics

How lasers work

Principle and working of a Laser

How Laser Technology is used



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Have a nice day. :)

Laser is an application with many use. Imagine how life would be like without most of its numerous functions, eg in digital music read in CDs and DVDs, in surgery, measurement, business, diagnostics, in fabrication, etc.

This is something i honestly dont want to imagine @greenrun

Sometimes i just wonder how people survived Several Decades ago without this Things

Thanks for stopping By Boss