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led fluorescent evolution, now gone through four generations:

The first generation LED Tube

Around 2005 led fluorescent shell is plastic, lamp beads uses F5 straw hat led lamp beads, circuit board uses a fiberglass board, power supply is built-in non-isolated power supply, then the whole effect of light about 40 -60LM / W.

        But soon discovered the fluorescent light fades very serious, life expectancy actually only 1000-2000 hours, which is mainly due to the hat light package structure and tube materials problems caused due mainly rely on two hat light radiating leg again Lamp circuit board with a glass plate, all the housing is plastic, so that the overall thermal performance is poor, the entire light as a power generated by the heat will be sealed in the tube and can not shed, which would cause the entire lamp will be scrapped in a short time, it also allows consumers lose confidence led lamp.

The second generation LED Tube

When it was discovered hat light lamp is not suitable for use, in 2007 or so most manufacturers do to start using SMD fluorescent light, aluminum housing are beginning to use half half plastic, circuit boards started using aluminum plate, but this is a rather messy period, using a light source 3528,3020,5050, etc., and even 1W high power led, and because each uses a different approach, the whole lighting effect in the 60-80LM / W or so, the power supply internal, external, isolated, non- Isolated variety of programs co-exist. At this time, the buyer becomes confused, and a variety of products a huge price difference, I do not know how to choose.

Third Generation LED Tube

2009 or so, the rapid development of the led, led lamp beads light efficiency is rapidly improved, high light efficiency (100LM / W), good heat dissipation, small start designing in 3014 SMD led lamp, the whole lighting effect is also raised to 70-100lm / W, at this stage because the effect is good, prices are down a lot, sales have begun to rise. Mainstream products on the market at this stage are based 3528,3014-based, but the target price and the people there are still many gaps.

The fourth-generationLED lamp

Around 2011, began to make use of 3014 SMD fluorescent, because single led lamp beads flux enhancement, to achieve the same luminous flux in the case of using a few pieces led lamp beads also reduced, costs are reduced, more importantly, 3014 SMD better thermal performance, light a larger, better rate, etc. Idemitsu advantage, it can be concluded that for a long period of time, the use of the core 3014 SMD led lamp light source is bound to become a trend.