LED lights have been gradually thorough popular feeling, energy saving has become the primary weapon of LED lights to take the place of incandescent light. Since almost all countries and regions published documents to show that they will eliminate incandescent light, as the representative of the new light resource, the prospect of a LED is full of light. Because of its small size, high efficiency, long service life, less consumption, and convenient use, LED lighting is popular with the majority of consumers.
According to the colors of light emitting light, LED auto light bulb can be divided into red, orange, green, yellow, green (further divided into yellow green and pure green), blue and so on. In addition, some light emitting diode contains two or three kinds of color chip. According to the light emitting diode is mixed with scattering diluents or not, colored or colorless, the sorts of colored LEDs above can also be divided into colored transparent, colorless transparent, colored scattering and colorless scattering these four types. Scattering type of LEDs is usually used for indicator light. According to the characteristics of the light emitting surface, there are circular LED light, square LED light, rectangular LED light, surface glowing tube, lateral tube, surface installed micro tube and so on. Circular LED light is divided into φ 2 mm φ 4.4 mm, φ 5 mm, φ 8 mm, φ 10 mm and φ 20 mm according to the diameter. At abroad usually call the φ 3 mm LED (light emitting diode) as T-1; the φ 5 mm as T-1 (3/4); the φ 4.4 mm as T-1 (1/4).
The distribution of circular luminous intensity angle can be estimated by the size of half value angle. Speaking from the angle of the luminous intensity distribution there are three categories. First is high directivity. General for epoxy encapsulation, or metal reflection cavity encapsulation, and do not add scattering diluents. Half value angle is 5°-20° or much smaller, has very high directivity, can be used as local lighting, or coupled with light detection device to work like automatic detection system. The second is standard. Usually used as indicator light, the half value angle is 20°-45°. The last one is scattering type. This is the indicator light of a larger visual angle, the half value angle is 45°-90° or greater, contains large quantities of scattering diluents.
According to the structure of the light emitting diode, there are complete epoxy encapsulation, metal base epoxy encapsulation, ceramic base epoxy encapsulation and glass encapsulation structure. According to the luminous intensity and working current there are common brightness LED light (light emitting strength 100 MCD); the luminous intensity between 10-100 MCD is usually called high brightness LED light. In general the working current of LED is between more than 10mA and dozens of mA, and working current of low current LED is below 2mA and the brightness is the same as ordinary light tube. In addition to the classification method above, the chip material classification and function can be the classification basis.