Standardized unit of measurement of the total amount of light that is produced from a light emitting source. The higher the number, the brighter the light.Optical Efficiency
Measures how much the total lumens sent into that component come out of it, through the optical surfaces. The higher the rating the greater the amount of light being broadcast. (See Raw vs. Effective Lumens)LED Watts vs. Power Consumption
Because an LED can be driven at its full capacity doesn't mean there is benefit in doing so. For example, a 3W LED can be driven at 3W, a 5W LED can be driven at 5W, etc. Driving an LED at maximum power generates higher temperature, which decreases lifespan. A balance between LED wattage and the lights; other components, such as the heatsink, allow for maximum operating efficiency and light output, while prolonging life expectancy.Raw vs. Effective Lumens
umen rating is typically one of the major factors used to valuate LED lights. But are those lumen numbers raw lumens, or effective lumens? What's the difference?
In the examples below, the LEDs are rated at 100 lumens each. Factors such as heat, lenses, and driving power of LEDs will affect the Raw Lumen value, resulting in a lower value which is the actual, or effective lumen output.
Raw lumen output is a theoretical value rather than an actual measurement of useful, or effective light. Raw lumens are calculated by multiplying by the theoretical output rate of the LEDs by the number of LEDs in the lamp.
Effective lumen output is the actual measurement of light output that takes into account thermal/optical loss, and the power level at which the LEDs are being driven. This is accomplished by using high-tech photometry equipment that measures the effective lumen output of a light.