LED Lights -Drivers-Optics
1 | Energy efficiency
LED lights use about 50 percent less electricity than traditional incandescent, fluorescent and halogen options, resulting in substantial energy cost savings, especially for spaces with lights that are on for extended periods. LEDs also aim light in a specific direction unlike conventional bulbs, which emit light—and heat—in all directions (because LEDs are mounted on a flat surface, they emit light hemispherically rather than spherically). This directional lighting capability reduces wasted light and energy.
2 | Extended life
Unlike incandescent lighting, LEDs don’t “burn out” or fail, they merely dim over time. Quality LEDs have an expected lifespan of 30,000–50,000 hours or even longer, depending on the quality of the lamp or fixture. A typical incandescent bulb lasts only about 1,000 hours; a comparable compact fluorescent lasts 8,000 to 10,000 hours. With a longer operational life, LEDs can reduce labor costs of replacing bulbs in commercial situations, achieving a lower maintenance lighting system.
3 | Cold temperature operation
LEDs love the cold unlike fluorescent lamps. At low temperatures, higher voltage is required to start fluorescent lamps, and luminous flux (the perceived power or intensity of light) is decreased. In contrast, LED performance increases as operating temperatures drop. This makes LEDs a natural fit for refrigerated display cases, freezers and cold storage spaces in addition to outdoor applications such as the parking lot, building perimeter and signage. DOE testing of an LED refrigerated case light measured 5 percent higher efficacy (the efficiency of a light source in lumens per-watt, like miles-per-gallon) at -5°C, compared to operation at 25°C.
4 | Durability
Without filaments or glass enclosures, LEDs are breakage resistant and largely immune to vibrations and other impacts. Traditional lighting is usually contained in a glass or quartz exterior, which can be susceptible to damage. LEDs, on the other hand, tend not to use any glass, instead they are mounted on a circuit board and connected with soldered leads that can be vulnerable to direct impact, but no more so than mobile phones and similar small electronic devices.
5 | Instant on
Most fluorescent and HID lamps do not provide full brightness the moment they’re switched on, with many requiring three minutes or more to reach maximum light output. LEDs come on at 100-percent brightness almost instantly however, and with no re-strike delay. This can be advantageous following a power outage or anytime employees open a building during early morning hours when it is still dark outside.
6 | Rapid cycling
Traditional light sources tend to have a shorter lifespan the more they’re switched on and off, whereas LEDs are unaffected by rapid cycling. In addition to flashing light displays, this capability makes LEDs well suited for use with occupancy or daylight sensors.
7 | Controlability
It can take more than a few dollars to make commercial fluorescent lighting systems dimmable, but LEDs, as semiconductor devices, are inherently compatible with controls. Some LEDs can even be dimmed to 10 percent of light output while most fluorescent lights only reach about 30 percent of full brightness. LEDs also offer continuous, opposed to step-level, dimming (where the shift from 100-to-10-percent light output is smooth and seamless, not tiered).
8 | No IR or UV Emissions
Less than 10 percent of the power used by incandescent lamps is actually converted to visible light; the majority of the power is converted into infrared (IR) or radiated heat. Excessive heat and ultraviolet radiation (UV) presents a burn hazard to people and materials. LEDs emit virtually no IR or UV. Rapid advancements in LED lighting technologies, with more improvements on the horizon, have resulted in lowered costs and increased reliability of LEDs. And while it may be tempting to assume LEDs are the right choice for all applications because of their energy efficiency, selection should be based on a combination of factors, including light quality and distribution, dimmability, and expected lifetime.
Before the LEDs can perform at their max, they require LED drivers to provide better longevity, reliability and efficiency. An LED driver manufacturer creates drivers that prevent damage to your LED setup by regulating voltage based on temperature changes, reducing thermal inefficiency.
When we think of an LED optic, we tend to think of a clear plastic lens that is placed on top of the LED itself to focus or spread the light. If this is your thought process, you’ve gone too far. Lets take a step back and look at the LED itself. See that small protective dome over the diode? That is actually called the primary optic which serves to protect and shape the output of the small diode. The light from the LEDs primary optic is still too broad for most applications, lacking intensity over distance. This is why most LED fixtures use secondary optics (lenses, reflectors, TIR optics, etc.) to collect all that light and magnify its intensity towards the target.
Creating lenses and reflectors for LEDs (solid-state lighting) is much different than just scaling them down from other light sources. This might seem like a logical way of creating them, as LEDs have much smaller form factors than other light sources, but they also differ in how they emit the light. As you can see from incandescent bulbs, they illuminate in 360 degrees, but LEDs are directional lighting, illuminating only 180 degrees. This is attributed to the design of an LED, as you can see to the left, a light emitting diode consists of one or more die, mounted on a heat-conducting material, with the primary optic enclosing the die. Therefore, the maximum angle LEDs can emit is 180 degrees as the substrate is on the back side of the die.