Led will definitely become the fourth generation of lighting, its development momentum is getting more and more fierce, the main advantages are: energy saving and environmental protection, long life, no stroboscopic does not hurt the eyes, does not attract mosquitoes. As long as the heat dissipation design of the high-power Led lamp is good enough, the life of 3-5 million hours is no problem (the definition of life is: because the Led is a semiconductor component, the chips is affected by temperature will produce light decay, when the luminous flux of the Led is When the light decay is reduced to 30% of the initial luminous flux, basically Led lamp has no illumination meaning, that is, the life is summarized. Although the Led light can still be lit at this time, but the brightness has been seriously reduced, so the heat release is very important to led product, very important, very important).
The object illuminated by the Led lamp will be color cast because of the lack of a color in the spectrum, which is the wrong idea. Quite simply, color TV sets (CRT) are not just a mixture of three primary colors (red, green, blue) to get a variety of colors. The lighting uses a large amount of high-power white light Led, mainly the blue light wafer excited phosphor mixed to obtain white light.
Objects illuminated by Led lamps will be color cast, mainly due to two factors:
1. The Led color rendering index used is too low, so that the emitted light does not reflect the true color of the object. (The ability of the light source to color the object is called color rendering, the color rendering index Ra is up to 100, and the color rendering is best.) If the LED color rendering index reaches 80-85, it is already very good, and it can be used indoors.
2. The color temperature of the Led used is not good. A simple understanding can be considered as the color of light. If the color temperature is low, the light will be greenish and reddish, and if it is too high, it will be blue. It is not suitable for indoor lighting. Therefore, indoor lighting is a very important parameter for the color temperature of Led lights. Led generally defines a color temperature of 2700K-4000K for warm color, 4000K-5000K for natural white, 5000K-6700K for white, warm white and natural white temperature will give people a warm, warm feeling, suitable for hotels, hotels, and bedroom. And Natural White gives people a cool and refreshing feeling, used in the office, the living room is more illuminated (fluorescent lights are generally more such color temperature).
The brightness is equivalent to 100W energy-saving lamps, it depends on the light efficiency of the Led lamps used (lumen/watt), the same wattage, the higher the luminous efficiency of the Led lamps, the higher the brightness. Generally, if the luminous efficacy of the Led lamp reaches 70 lm/w, the brightness of the energy-saving lamp of 100 W can be exceeded as long as 50-60 W is used.
The last thing to say is to buy Led lamps to pay attention to light efficiency, color temperature, color rendering index, light decay. The first three are common parameters for all illumination, and the final light fading is a unique property of Led as a semiconductor.
In addition, some people have the following misunderstandings when choosing Led lights:
1. The expectation of the actual lifespan is too high.
Led manufacturers expect Led life to reach 100,000 hours MTBF
(Average time between failures, the standard used by traditional illumination manufacturers to measure lamp life). However, like all basic light sources, Led’s lumen flux is also attenuated over time. So although Led can be used for a long time, MTBF is not the only consideration for determining service life.
The attenuation of Led lumens is affected by many environmental conditions such as ambient temperature, humidity and ventilation. Lumen attenuation is also affected by control, thermal management, current levels, and many other electrical design considerations (cited by CK Corporation, USA).
Many salesmen may provide customers with some ambiguous information for some reason when selling Led. For example, Led has a service life of about 100,000 hours. Here, 100,000 hours refers to the life expectancy of the manufacturer. As the light source of illumination, the brightness of the lamp has a process of gradually decreasing and darkening (such as fluorescent lamp, energy-saving lamp), which is referred to as light decay. In the application-grade Led, when the light decay exceeds 50%, the human eye can clearly feel the change of brightness. At this time, the brightness of the product is not suitable for illumination. Many manufacturers and contractors use Led at a low price for three months to half a year. It is often found that the brightness of Led is not as bright as when it was just installed, or even close to nothing, precisely because it does not take into account the cause of Led light decay. In summary, when we buy Led, we should pay attention to its light decay speed, not the use time.
2. Treat the actual illuminating angle as an effective angle.
The illumination angle of the Led is divided into an effective angle and an actual illumination angle. The angle at which the luminous intensity value is half of the axial strength value and the angle of the luminous axis (normal) are effective angles. The angle of view of twice the half value angle (or half power angle) is the actual illumination angle. Angles other than half of the axial strength are too weak for practical applications. Therefore, when you purchase a product, you should pay attention to the actual illumination angle of the product. When calculating the number of products used in the project, the actual illumination angle is used. The effective illumination angle can be used as a reference value.
3. The higher the power, the higher the brightness.
The brightness of Led is measured by the luminous intensity, which is the luminous intensity in the direction of the normal (for the axis of the cylindrical luminous tube), that is, the luminous flux emitted by the unit solid angle, in units of candle light (Candela, cd). Since the luminous intensity of the general Led is small, the luminous intensity is usually measured in millicald (mcd). Generally speaking, the light source emits its luminous flux at different intensities in different directions, and the visible light radiation intensity emitted by the solid angle in a specific direction is called light intensity, which is simply referred to as axial brightness.
The concept of electric power is introduced from the amount of work done by force in equal time. The current is fast and the electric power is large; the current is slow, the electric power is small, or the electric work is more in the same time, the electric power is larger. On Led, the greater the power, the higher the brightness of the product. So what we pay attention to when purchasing Led is its axial brightness, not power.
4. About the purchase of white Led Led module.
High-brightness (blue-green) white light Led is sensitive to static electricity and is determined by the characteristics of Led itself. Exceeding the maximum forward DC current and maximum reverse voltage it can allow may cause damage or breakdown of the Led. For example, a three-lamp Led module, each lamp will have an anti-static resistor, plus a resistor for current limiting, a total of four. The antistatic resistor can effectively suppress the damage caused by static electricity to Led.
iPHD Lighting Co., Ltd is focus on led landscape outdoor lights from 2009, we produce led floodlight, Led Wall Light, led street light, led linear wall washer light bar, led underwater light, led swimming pool light, led highbay light, led garden yard lamp, led tree light, etc. 100% of our products are sold to European countries, South America and North America. We hope there is a chance for us to service your company in the short time