On the computer and protection of electromagnetic radiation

Abstract: The Computer has become a daily work and life are essential and important tool, the Computer will give Computer users the electromagnetic radiation health hazards, how to prevent and reduce the Computer's electromagnetic radiation is a Computer user should be concerned about important issues. Any charged electromagnetic radiation around an object will, as a computer major charged components, the host is a computer monitor and the two main sources of electromagnetic radiation, select LCD monitors and chassis with excellent shielding to prevent and reduce computer radiation is the key.

Keywords:: electromagnetic radiation, electromagnetic field computer
1 Overview
Any charged object exists around the electric field, while the periodic variation of the electric field will produce periodic changes in magnetic field, then, there is electromagnetic waves, electromagnetic radiation, the amount of radiation than if this qualification, it will be the formation of electromagnetic pollution on the environment. and nowhere to hide in air pollution, water pollution, noise pollution, as electromagnetic radiation the same everywhere, making it recognized "the fourth source of pollution."
Where the electric field changes as long as there will be electromagnetic radiation. Currently, the electromagnetic pollution caused by large area of the main high-voltage transmission and distribution systems, transmission equipment, microwave equipment, household appliances, computers and so on. High-voltage transmission system in which the electromagnetic radiation intensity largest, the most significant harm to human body. In order to protect the health of practitioners, working in the radiation environment has a strict time limit. In contrast, such as color TV sets, mobile phones, microwave ovens, air conditioners, refrigerators, computers, and so the family electrical equipment necessary for the broader population affected. In the common electrical devices, and people work and live computer more closely related concern. many working people and indulge in the geek world face every day the network computer time is often more than 8 hours. The computer itself is an electromagnetic radiation source can not be overlooked: microprocessors, motherboards, video cards, sound cards, memory, hard drives, optical drives, monitors, USB interface, and other major components are at work, the electromagnetic energy radiated to the outside world. computer produced by electromagnetic radiation, the long-term exposure to computers for those people who have great mental and physical health hazards.

2 computers on the health hazards of electromagnetic radiation
Computer has access to thousands of families in modern society and all walks of life, it gives people work, study and life has brought great convenience. But the "Computer Disease" is also growing, serious impact on people's physical and mental health. "Computers disease "symptoms of neurasthenia comprehensive cancer (dizziness, headache, fatigue, insomnia or nightmares, memory loss, depression, etc.), neck and wrist syndrome (skeletal discomfort, such as finger Ma, paresthesia, tremor, there is tenderness ), and back pain, lower disease resistance, easy to colds and other, the highest incidence are those daily keystrokes on the computer next to the professionals. These professionals, mental stress, the brain is highly concentrated and the tensions that is to produce the source of neurasthenia syndrome. abortion, facial brown spots, similar to the appearance of erythema or eczema, etc., are also closely related with the spirit. professionals continuously monitor the computer screen for a long time staring at the flickering screen at close range, easy to make eye congestion, dry, sensitive to light, severe eye will make the light-sensitive retinal dysfunction, crystal damage, decreased dark adaptation, resulting in vision loss, and even can lead to microwave from the inside barrier, night blindness and so on. If the human body by radiation can also lead to human circulatory system abnormalities, decreased male reproductive capacity, the body abnormal hormone secretion. pregnant women, children and the elderly, pacemaker wearers are susceptible of electromagnetic radiation, while the heart, eyes and reproductive system is the electromagnetic radiation sensitive organs. In recent years, deformed children and children in the birth rate increased from leukemia, heart pacemaker wearer increased mortality, electromagnetic radiation escape the blame.

3, the main source of computer radiation
Although microprocessors, motherboards, graphics cards, sound cards, memory, hard drives, optical drives, monitors, USB interface, and other major components are at work, radiated electromagnetic energy to the outside world, but fortunately, in addition to the monitor, these parts are to be installed electromagnetic shielding ability in the chassis inside, blocking most of the electromagnetic radiation. So, we were usually the one hand, the radiation from the monitor, while on the other from the host. If the display technology in electromagnetic shielding is not stringent enough, then the user may be 5 days a week, 8 hours per day are subject to electromagnetic radiation, the health risk is obvious. The same is true of the chassis, poorly designed products are often units of electromagnetic radiation leak occurred, if the distance between the chassis and the user too close, leakage will affect the electromagnetic radiation to the user health.

All this shows that the electromagnetic radiation mainly from the computer monitor and the host. In which the display is divided into CRT monitors (cathode ray tube monitors and LCD monitors (liquid crystal display. CRT computer monitor is the most serious source of radiation. CRT monitors emit electrons through the electron gun bundle of screen display, external emission electron itself will have a serious electromagnetic radiation, although the thick leaded glass screen can be separated to some extent radiation, but there are still a lot of e-penetrating barrier layer exposed directly to the user. So, how to reduce this part of the radiation is essential.

In accordance with the definition of physics, radiation damage from CRT displays can be divided into light radiation, low energy x-ray, radio and electrostatic fields and low frequency electromagnetic fields. Which light radiation is the electron gun behind the screen playing the visible light emitted fluorescent layer and a small amount ultraviolet light, only a small amount of UV will cause harm to humans. X-ray beam from the electron collisions within the cathode ray tube screen produced by the former, but because the energy is very low, the radiation level can be negligible. radio field mainly from the CRT control circuit part of the issue, the intensity is very weak, after a short distance after the decay essentially to zero. electrostatic field from the CRT electron gun is accelerated within the electric field generated, the most direct manifestation of the screen that will attract dust. The damage to human health are considered The most serious should be low-frequency electromagnetic fields, which mainly monitors the power supply part (coil) and vertical / horizontal scan produces electric field, electromagnetic frequencies between 5Hz ~ 400kHz.

LCD electromagnetic radiation is relatively lower. From the principle that, LCD monitors to liquid crystal materials as light through the screen switches to control light exposure, and then get the screen output. And this process was not involved in ultraviolet light, electric field, high-voltage power supply and so easy to produce radiation components, so it can be said from this side to consider the positive almost zero radiation LCD. In addition, LCD and CRT monitors, as the same machine requires a high voltage power supply, but not the power-driven gun, but the LCD backlight module in the cold cathode fluorescent tube. such a fluorescent lamp in fact, like our common, require a higher voltage to drive, but light will come down quickly after the voltage to a lower level. Thus, LCD's power supply only needs to maintain a certain time high pressure (up to l000V, and then converted to atmospheric pressure or low pressure, rather than the same coil as the CRT monitors always have to maintain a high voltage state. So relatively speaking, LCD monitor power supply of external low-frequency electromagnetic radiation than the CRT to much weaker, with the placement of LCD is often close to the wall. it will not be back to the human body, the human impact of this radiation can be reduced to zero.

Display, the second radiation source is the host. We all know, the metal chassis of the shielding of electromagnetic radiation may play a role, but different materials, different designs, different processes of the radiation capacity of the chassis is not the same, if poorly designed, host outside leakage of electromagnetic radiation may still be excessive. reposted elsewhere in the Research Papers Download http://www.hi138.com First of all, the chassis material is essential, most current chassis are galvanized copper, it can play a good shielding effect. a lot of high-grade aluminum alloy chassis is lighter, the same radiation has a good ability. materials is only the basic aspects of radiation protection requirements, but the key part is that the chassis manufacturing process, only the mold fine, good manufacturing process chassis will be a good shielding effect. this is mainly reflected in the chassis panel, front port, rear baffle and all other places there are no seams, poor quality of the chassis chassis and the great differences in this respect, the former received joints are usually very tight, design, manufacturing process, no rigorous testing laboratory by radiation, electromagnetic radiation leak in serious condition. particularly in the front interface, the electromagnetic radiation is very easy to directly affect the user. The quality of the chassis In these details are more stringent, there is no basic problem of joint seal is not enough, the sample will be created after the items are measuring the electromagnetic radiation on the laboratory standards, the election can be carried out after standard high-volume manufacturing. In addition, a number of chassis are used in order to create convenient double-sided painting, but the internal surface to be painted if so, the chassis plate can not be directly absorbed electromagnetic slope, wave scattering occurs around the situation. If not tight seams in the chassis easily caused due to electromagnetic wave scattering leakage. In contrast, the outer surface of the painting, the practice of internal zinc is more worthwhile to promote. plate of zinc-plated surface (oxidation required) is also metal, the electromagnetic wave after hitting the surface can be effectively shielded and will not appear scattering phenomenon, which is a whole case of electromagnetic radiation shielding is very favorable - from a health point of view, we believe that the budget and spend more to buy good quality case or be advocated.

Therefore, for the majority of computer users, the choice of LCD monitors, buy a reasonable selection, design quality, well-shielded enclosure is very important. This will ensure maximum computer users from harmful electromagnetic radiation by the excessive.

In addition to the time chosen for the purchase of electromagnetic radiation standard computer, you can also take the following measures under the circumstances. �� normal diet should choose foods rich in vitamins, to reduce the radiation hazards �� need to use protective products, such as shield, protecting eyepiece, magnetic posts �� prolonged use of protective clothing and other computers, should pay attention to the interval with the swap, pregnant women should not exceed one day operate a computer 2h. �� human and computer, should maintain a safe distance. indoor settings for office and home appliances should not be too dense, Do not put too focused on household appliances, so as not to expose themselves to risk of radiation overdose.

4 Conclusion
With the computer into people's daily lives, it gives the modern work, study has brought great convenience, become an indispensable production tool for life. In the same time to bring convenience, it should be noted that the electromagnetic radiation generated by the computer but also to people's health hazards. How to effectively prevent and reduce the threat to human health computers, production and life of people in the care and concern should be a problem. the main computer of the electromagnetic radiation from the display and the host, select the LCD display and the chassis has a good effect of radiation is electromagnetic radiation to prevent users from over-critical. Also increase vitamin intake, select the protective equipment, avoid prolonged close contact is also important to computer protection measures.

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