Electric Light Source
Release Time：2016/1/27 10:36:24 News Source：admin Views：8391
Will be converted to solar power device or devices. Widely used in day-to-day lighting, industrial and agricultural production, national defense and scientific research.
A brief history of human research on the electrical source at 18, the end of the century. The early 19th century, the United Kingdom David H. invented carbon arc lights. In 1879, the United States of TA Edison invented the practical value of the carbon filament incandescent lamp, so that mankind from lighting the fire long into the era of electric lighting. Drawn in 1907 using as a tungsten filament incandescent body. In 1912, the United States and others I. Langmuir incandescent conduct a study on inflation, raised the efficiency of incandescent light-emitting and the prolongation of life, and expand the scope of application of the incandescent lamp. 30 In the early 20th century, the successful development of a low pressure sodium lamp. In 1938, Europe and the United States developed a fluorescent lamp, light-emitting efficiency and life are 3 times more than incandescent, electric light source technology which is a major breakthrough. 40 era of high-pressure mercury lamp to enter the practical stage. 50s at the end of a very small volume and the halogen light decline came and changed the thermal radiation light sources stagnant state of technological progress, which is electric light source technology, another major breakthrough. 60s has developed a metal halide lamp and high pressure sodium lamp, the luminous efficiency much higher than the high-pressure mercury lamp. Appeared in the 80s small diameter energy-efficient compact fluorescent lamps, low-power and low-power high-pressure sodium lamp metal halide lamp, so that electric light into the smaller, energy-saving and electronic new era.
The invention of electric light source to promote the construction of the electrical installations. Electric light conversion efficiency, energy supply stability, control and ease of use, safe, reliable and easy to use energy meter count, so they are more than one hundred years after its introduction, the soon to be universal. It not only become a daily necessity, but also in industry, agriculture, transportation, as well as national defense and scientific research, have played an important role.
Lighting the worlds electricity (lighting power consumption) of total generating capacity of 10 ~ 20%. In China, the total lighting electricity generating capacity by 10%. With the development of Chinas modernization speed, lighting electricity consumption increasing year by year, while electricity growth rate is incompatible, so the research, development and popularization and application of energy-saving electric light source has attracted great attention.
In 1984, the worlds total output of electric light source of about 12 billion, of which 3.82 billion U.S., the Soviet Union 2460000000, 1860000000, Japan, China 1,310,000,000. Electric light source for industrial development in China soon. In 1949 an annual output of only 10 million, in 1987 has risen to nearly 1.7 billion (not including Taiwan Province). Manufacturing enterprises across the province, and has formed a special raw materials from production to production of supporting parts, from scientific research and development, education and training to the production of a relatively independent, complete industrial system of electric light source.
Category Electric Light Source in general lighting can be divided into two major categories and radiation light source. Lighting is lighting for the purpose of radiation being the main visual of the visible spectrum (wavelength 380 ~ 780nm) of the Electric Light Source, and its specifications for a wide variety, power from 0.1W to 20kW, produces light output power above 95%. Radiation source is not for the purpose of lighting, to a large number of UV radiation (1 ~ 380nm) and infrared spectra (780 ~ 1 × 106nm) of the Electric Light Source, which includes ultra-violet light source, infrared light source and the visibility of non-lighting light source. The above two categories are non-coherent light source. There is also a class of coherent light source, through the excited state by stimulated emission of radiation particles under the light output from the short-wave ultraviolet wavelength until the far-infrared, such as the laser light source.
Lighting many varieties, according to the form is divided into light-emitting thermal radiation light source, gas discharge light sources and electroluminescent light source 3.
① thermal radiation light source: current flows through conductive objects, so that at a high temperature solar radiation light source. Including two types of incandescent and halogen.
② gas discharge light sources: current flows through the gas or metal vapor, to produce gas discharge and LED light source. Gas discharge there arc discharge and glow discharge two discharge voltage and low pressure, high pressure and ultra-high three kinds of pressure. Arc discharge light sources include: fluorescent lamps, low pressure sodium lamp, such as low-pressure gas discharge lamp, high pressure mercury lamp, high pressure sodium lamp, metal halide lamp high-intensity gas discharge lamp, ultra-high pressure mercury lamp, such as ultra-high pressure gas discharge lamp, as well as carbon arc lamps, xenon lamp, some spectrum light source such as a larger span of discharge pressure gas discharge lamp. Glow discharge light sources including the use of negative-hui District glow glow discharge instructions and the use of light glow discharge positive column of neon lights, both low-pressure discharge lamp; also includes some of the light source spectrum.
③ Electroluminescent light source: In the electric field, so that the light source emitting solids. It will power directly into light. Including electroluminescent light source and two light-emitting diodes.
The structure and properties of different types of electric light sources have different structures, but generally have the following part of the parts: as a luminous body of the filament, electrodes, phosphor; as a luminous body shell of glass, translucent ceramic tube, quartz tube; As a lead wire, core columns, lamp; as filling various gases, mercury, metal and halide; Getter, all kinds of coatings, insulation and adhesives, such as.
Electric Light Source major performance indices are six:
① indicator light features. Including the total flux, brightness, light, ultraviolet and heat radiation level.
② indicators photochromic properties. Including the light color, color temperature, color rendering, color and spectral distribution.
③ indicators electrical characteristics. Including the consumption of power, lamp voltage, lamp current, start features, such as noise and interference.
④ mechanical properties. Including geometry, lights and other structures and lamp.
⑤ economic characteristics. Including light-emitting efficiency, longevity, price, and electricity and so on.
⑥ psychological dimension. Including the lights look and comfort.
Production processes except for some small-batch production of special light source, the large number of electric light source has been the adoption of modern medium-speed and high-speed automated production line, the product of high quality, high productivity and low cost. Ordinary incandescent lighting the main production processes, including melting glass, blown glass, filament winding, the production of the core columns, loaded planes, sealing, venting, and assembly and so on Aging. Fluorescent also drawn glass tubes, coated with phosphor, baking, production processes electrode.
The main trend of development is to improve the luminous efficiency, development of small and efficient energy-saving light source, to improve the electric light source color, and prolonging life. Achieve the above purpose is to develop specific ways to develop new materials, new technology and to further study the new light-emitting mechanism, development of new power source, and most realistic way is to improve the existing electric light source technology, using new, automated performance good production facilities.
The main performance parameters of electric light sources in addition to the main performance parameters generally reflect the performance of the parameters of light sources (such as the luminous flux, luminous intensity, illuminance, luminance, color temperature, color and color-rendering index), there are light-emitting efficiency, light source life, starting with the re-start performance.
① flux: light source in the unit time to the surrounding space radiation and cause visual energy. Because the human eye to different wavelengths (λ) of light sensitivity of different feelings (for a wavelength of 550 nm yellow and green the most sensitive), so not only with the light flux of radiation, strong or weak, but also the efficiency of light source spectra of light on the function . Flux equivalent to the radiation source power and spectral efficiency optical function (also known as the relative see rate) multiplied by the unit for lumens (lm). l lumen equivalent to a wavelength of 550 nm monochromatic radiation, its power is 1 / 680 watts of flux.
② luminous intensity (light intensity): light source in a particular direction within the unit solid angle of radiation flux. Hom units (cd).
③ Illuminance: body per unit area exposed to receive the flux. Le unit (lx). Moonlight over fine ground illumination Le 0.21.
④ brightness: the light source in a given direction unit projected area on the luminous intensity. Unit Hom / m 2. Cloudless skies, the average brightness of 0.5 × 104 Hom / m 2,40-watt fluorescent surface brightness of 0.7 × 104 Hom / m 2.
⑤ temperature: the color of LED light source with the blackbody heated to a temperature of light emitted by the same color, the temperature of light source color temperature, referred to as color temperature, incandescent color temperature for 2400 ~ 2900K.
⑥ Color: The light show was the color of objects according to performance. The same color of objects with different spectral power distribution of light exposure will show different colors.
⑦ color-rendering index: the color of objects in the test radiation light source with another similar or daylight color temperature of the blackbody radiation light source under the light of the degree of conformity. Color distortion at least a high color-rendering index, the light source color is good. The light of the provisions of the international solar light source color-rendering index is 100.
⑧ luminous efficiency: referred to as luminous efficiency, saying that electricity consumption for every 1 watt light power emitted by the luminous flux, units for lumens / Watt (lm / W).
⑨ source life: Life is divided into an effective life and the average life expectancy. Life means the light source can no longer be the starting point and LED lighting when the time; useful life of the LED light source refers to the efficiency of the initial value dropped to 70 ~ 80% Total ignited when the time; the average life expectancy refers to a sample test each batch of products that the average useful life value.
⑩ starting with the re-start: Electric Light Source starting with the different light sources have different requirements. Usually associated with the supply voltage, starting when the temperature as well as ancillary electrical appliances and so on.
Electric Light Source Laboratory of Fudan University bibliography edited by: "Principles of Electric Light Source", the Shanghai Peoples Publishing House, Shanghai, 1977.