Most people identify LED from their size and color; but here are some core differences between a regular incandescent light and an LED:
An incandescent light bulb is a simple device with a tungsten filament which consistently produces light with the same characteristics. Whereas LEDs produce light through the use of a semi-conductor that emits light energy when an electrical current is passed through it. LED lights get their color from a phosphorus coating, which needs to be applied consistently during manufacturing; else it ends up producing different shades of color. Also, LEDs should not emit a lot of heat, as incandescent bulbs do; else it loses its efficiency dramatically.
Below is a list of 5 things to look for before buying an LED light to insure a beautiful and consistent color, long life, and maximum efficiency.
- What is the CRI (Color Rendering Index) of the LED light?
Each bulb is given a CRI score. CRI stands for color Rendering Index and is a measure of the ability of a light source to accurately represent different colors. Put simply, you want to make sure you get a bulb that makes your tomatoes look red, rather than a strange orangey color. Traditional incandescent and halogen bulbs are near perfect and score in the high 90s. LEDs and CFLs are a little behind this and are more likely to have a CRI value in the mid-80s. 80 is considered an acceptable level, although like many things it comes down to personal preference.
- Do the LED Lights Produce Consistent Color?
The circuitry of the LED should continually measure and adjust the output of the light to insure it is consistent in color temperature from fixture to fixture and over time as well. Ask your LED salesperson if the LED lights you are buying will be consistent in color temperature.
- Direction of Light: Will the LED Light Shine Light Where I Need It?
An LED is a small semiconductor chip, which by nature only emits light in one direction. LED manufacturers then place a lens on top of the LED to either narrow or widen this light. Unlike an incandescent lamp, most LED lights come with a specified beam spread. Whether you need a 10° spot light, a 60° flood light.
- Does the LED have an Effective Thermal Management System?
The LED fixture should be designed to effectively pull the heat away from the LED. Many people think LEDs do not produce any heat. This is not true. They do produce a small amount of heat, but at the small junction on the LED surface where the light is being produced, the heat is intense. A well manufactured LED light using LEDs of .5 watts or more will have a piece of metal with fins for cooling as part of the fixture.
- Find out if the LED has a dimmer.
Points to keep in mind when reading a label:
- LEDs are measured in lumens and not watts, higher the lumens higher the brightness.
- Life of the LED measured according to an average of 3 hours per day
- Light appearance: Warm/Soft White colors (at or around 2700 Kelvin) have a lower color temperature and an inviting, comfortable and relaxing atmosphere similar to the light from an incandescent bulb. Cool/Daylight bulbs (closer to the max of 6500 Kelvin) create a bright, clean and lively mood with a bluish tone.
- Make sure you buy a bulb which has the best shape and fitting to replace your existing lights (carry an old light bulb with you to the store).
- Check the CRI value
Hope you understand LEDs better now and make a knowledgeable decision on which ones would suit your project.