Optical Communication
Optical communication is defined as a communication in which light carries signal from one end to another. Optical communication depends on optical fibers to carry out the signals to the other end or to the destination. Optical communication has three building blocks transmitter, receiver and medium. Optical fibers are used as transmission medium.
Advantages of Optical communication/Optical fiber:
• Optical Fiber Cables can run long distance like 40KM, without repeating. For long distance we use Single Mode Fiber Cables.
• Optical Fibers are of very small diameter like a human hair. There diameter is 125um whereas of copper cable it is 0.8mm.
• Optical Fibers have no speed or bandwidth limitations. Maximum capacity of single mode step index fiber is 1.6TB/SEC w.r.t coaxial cable bandwidth of 500MHZ.
• To upgrade the fiber communication it is easy to replace the optics or components without changing all the underlying cabling.
• Optical Fiber Cables carry duplex communication, as upstream and downstream by using two cores Transmission (Tx) and Receiver (Rx).
• Optical Fiber Cables can be laid within (Indoor Fiber Cables) or outside (Shielded Fiber Cables) the buildings because they are flexible.
• As optical fiber cables carry light so they are not influence by Electromagnetic Interference.
• Optical Fibers provide a high degree of security.
• Optical Fiber is made up of dielectric as glass so there is no cross talk or leakage.
• Glass is used as an optical fiber transmission medium which is made up of sand and is available in abundance.
• Optical Fibers are light weight and can be handled easily.
• Line amplifiers and repeaters are reduced due to low transmission loss,...
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...bon dioxide and argon-ion lasers are used for this purpose because they pierce deep into the tissues. Dye lasers are also used in this treatment because they heat the stones in the kidney.
5. Dental treatment:
Dentists make use of Laser beams for dental treatment, like drilling cavities, antibacterial surgery, gum surgery and many more. By lasers all these treatments can be done without any pain. All tooth infections can be cured by lasers beams.
6. Cosmetic treatment:
Removal of hair, tattoos, spider veins, age marks and births marks are also done with the help of laser beams.
Laser therapy has been accepted widely by the general public and the medical professionals for its extensive benefits. This therapy precisely targets the affected area, minimizes the use of general anesthesia, encourages shorter hospital stay and improves the patient outcomes. These benefits have lead to its increased use and importance worldwide.
In September 1959 DiVita asked 2nd Lt. Richard Sturzebecher if he knew of a way to produce a strong glass fiber that would be capable of carrying a light signal. Sturzebecher had melted 3 triaxil glass systems together for his senior exam at Alfred University. In his exam, Sturzebecher had used SiO2, a glass powder produced by Corning. Whenever he had tried to look at the substance through a microscope he would end up with headache. Sturzebecher realized that these headaches came from the high amounts of white light produced from the microscopes light that was reflected through the eyepiece via the SiO2. SiO2 would be an ideal substance for transmitting strong light signals if it could be developed into a strong fibre.
Laser method is used widely now a days in acne scar treatment, for acne skin removal uses the wand-like equipments that emits laser rays which burns off the acne scared skin and thus enabling fresh skin formation. The benefit of the laser treatment is that laser penetrates to the skin as the moisture content in the skin easily absorbs it. The lasers that are employed mainly for the acne scar removal are
Throughout the 1970s, concerted industry efforts at the federal, state and local levels resulted in continued lessening of cable restrictions. These changes, couples with cables pioneering to satellite communications technology, led to a pronounced growth of services to consumers and a substantial increase in cable subscribers.
Carbon fibers were discovered in the late 1800s by Thomas Edison. The early lightbulbs Edison created used the carbon fibers as filaments. These carbon fibers used to create the early lightbulbs had a substantial tolerance to heat, but they lacked the tensile strength of modern carbon fibers. Edison used cellulose-based materials, such as cotton or bamboo, to make his carbon fibers. He used a method called “pyrolysis” to cook the bamboo at high temperatures in a controlled atmosphere to carbonize bamboo filaments, making them fire-resistant and capable of enduring intense heat needed for luminescence.
This is the principle in fibre optics of which long glass fibres of very small
Lasers (The word laser is an acronym for light amplification by stimulated emission of radiation.) lasers were first introduced in 1960, The first successfully optical laser constructed by Maiman (1960), was a ruby crystal surrounded by a helicoilal flash tube enclosed within a polished aluminum cylindrical cavity cooled by forced air. The ruby cylinder forms a Fabry-Perot cavity by optically polishing the ends to be parallel to within a third of a wavelength of light. Each end was coated with evaporated silver; one end was made less reflective to allow some radiation to escape as a beam was produced. Initially the laser was named the invention looking for a job. Photo-pumped by a fast discharge flash-lamp, the first ruby lasers operated in pulsed mode for reasons of heat dissipation and the need for high pumping powers. Nelson and Boyle (1962) constructed a continuous lasing ruby by replacing the flash lamp with an arc lamp.(1) Today lasers are much like those of the early ones and they are widely used in many fields, their uses are wide spread, From fusion physics to the DVD player these are common places where lasers are used. Medicine and surgery are no exceptions from skin resurfacing to eye surgery to correct vision. With the development of lasers Physicians have been able to provide treatment for a large number of medical disorders. Medical lasers have made it possible to treat conditions, which were previously untreatable or difficult to treat. To make the most of the laser technology physicians must maintain a up to date understanding of laser systems and conditions for which each can be applied .To achieve these goals the basic terminology and fundamentals of laser-tissue interaction is needed.
All forms of commerce will benefit from fibre optic connectivity as it will lower the cost of communication, which is a vital part of any business. New opportunity for the growth of the data market will emerge as cheaper bandwidth should translate to more users.
Most networks transfer data in two directions and are known as duplex communications links. Duplex links are classified as either full duplex or half duplex (also known as two ways alternate), depending upon whether both local and remote nodes may simultaneously transmit, or whether one must wait for the other to finish before starting transmission.
The use of light as a communication media used in China Great Wall distance more than 7300 km with in 1 hour to sent signal from one tower to another. In the late 20th century optical communication took back in to the seat for its advantages over coaxial transport and other electrical communication system. In 1966, Kaw and Hockman proposed the idea of using optical fiber light wave communication and their prediction was data loss 20dB/km [12]. In late 1980s to 1990s, coherent detection communication systems were introduced to enhance the transmission system. However, optical system needs still regeneration over long distance. By early 1990s, the system channel capacity boosted and reached to 10Gb/s but in 2003 it reached up to 40Gb/s via support WDM system. Recently, some experiments have done to transmit data 21.7 Tb/s though crossing the 10Tb/s per fiber barrier and it is new challenges for optical communication to innovate novel schemes of optical amplification, modulation technique or Fiber channel design.
Dentistry is an industry that is constantly evolving. Every day new techniques, instruments, procedures and discoveries are made. One thing becoming more and more popular in dentistry are dental lasers. Dental laser use in dental offices is rapidly growing because all of the advantages they provide to both the dentist and the patient. With the different types and strengths of the different lasers like hard tissue, soft-tissue, carbon dioxide, argon lasers and more almost any dental treatment can be benefited by using one. Lasers are allowing procedures to be performed quicker, more effectively and more comfortably.
As you can see lasers are a very useful and important tool which is why I have
Oftentimes, a person can look at an image and draw a conclusion about it, only to find out later that he or she was incorrect. This phenomenon is due to what is called an optical illusion, in which an image is perceived incorrectly to be something else. This leads to the questions, why do optical illusions occur, and what can be done about them?
This technology uses a visible spectrum and has not major ill effect as we know that the light is very much part of our lives. Moreover in this spectrum 10,000 times more space is available and it also multiplies to 10,000 times more availability as a light bulb available already.