When shopping around for LED lights, it doesn’t take long to run into huge variances in price, wattage, and guarantees. Lots of people ask about the differences between them. The fact is, while the number of high-quality and high performance LED products is increasing every day, there are quite a few products out there that just aren’t built to perform or to last.
In terms of technology, for example an LED bulb shares a lot more in common with a consumer electronics device than it does with a typical filament based light bulb. You wouldn’t have the same expectations of Rs.2500 camera as you would a Rs.20,000 camera, and that’s a good mindset to have when looking for an LED bulb as well. There are a number of components that are critical to a viable LED lighting product, and any bulb is only as good as its weakest link.
The chips are what actually generate light in an LED bulb, and the type, quality, and arrangement of the chips are of critical importance. They usually are mounted onto a layer of heat-conducting material, which is sometimes referred to as a wafer. Quality chips are specifically designed for the high light output and color consistency needed for use in general lighting. They are very different than those used in lower output applications.
In addition, when chips are manufactured, they fall across a range of color temperatures and light outputs. They are then sorted by grade in a process called binning. The best or “tightest” bins contain chips with the highest consistency in color and light output, and therefore these are the most expensive chips to buy. The most reputable manufacturers will only work with these chips in order to keep their product consistent from bulb to bulb. The rest of the bins are less expensive but are also much less consistent, these are used in many of the bargain LEDs on the market. Some of the least reputable product on the market doesn’t even use chips that are designed for lighting, and instead uses a number of low-power chips like those used in indicator lights.
The power management system, or driver, is what converts the voltage and current coming from the socket into what is used by the LED chip to generate light. It’s functionally similar to the ballasts used by fluorescent and HID bulbs. If this system is designed poorly the chip can either become overpowered, resulting in early failure, or underpowered, resulting in low light output.
LED chips generate heat, and this heat must be carried away from the components and dissipated, or the life of the chip and the driver assembly will be greatly reduced. This job is performed by the heat management system, which is also commonly referred to as a heat sink. A number of different heat sink designs are being used, but most are some variation of aluminum fins extending out from a metal core. Metal castings like these tend to be the industry standard, as metal conducts heat very effectively.
When light is generated by the LED chip, it is not necessarily headed in the direction where it’s needed. It is the job of the lens to focus and direct the light in order to “land” it in the proper place. The lens is particularly critical in reflector style bulbs (like PAR and MR types).