The Anatomy Of A Smart Bulb: What Makes Them So Special? March 01, 2017 00:00
When it comes to producing light for your home, there aren’t any options out there that’ll save you money like LEDs.
These bulbs use 75% less energy and have 25 times the lifespan of traditional incandescent bulbs and 2-3 times the lifespan of a fluorescent bulb.
And what’s more, with all the research funding from a variety of sources including the Department of Energy, LEDs have never been cheaper!
First and foremost: how does an LED create light?
But how exactly do these amazing bulbs work that make them so much more efficient than other bulbs? Well, the secret is in the fact that LEDs are a type of solid-state lighting, or SSL.
That means that instead of using electricity to heat a tungsten filament in a vacuum (like an incandescent bulb) or applying a current to a gas and then converting that energy to light (like a fluorescent bulb), solid-state lighting is simply applying electricity to a material. The result is less steps between the electricity and the produced light, giving you LED owners out there more efficiency.
It works like this: LEDs, or light-emitting diodes, are built from a semiconductor chip. This chip is made up of material that doesn’t fully conduct electricity or fully insulate from it, but is rather somewhere in between.
This material has both a positively charged part and a negatively charged part to it. What this breaks down to on a molecular level is a part that has electron “holes” (that’s the positive part) and a part that has a bunch of extra floating electrons (that’s the negative part). When you add electricity to the equation, those extra electrons from the negative side will jump into the holes of the positive side, a process which has the side effect of producing light!
The main takeaway from this, though, is the fact that the electricity interacts directly with the material that creates the light and there really aren’t any moving parts in the system. There are heat sinks to take away some of the excess heat from the system (that’s the part that takes up half the bulb and makes them look so different) and covers to the diodes but not a whole lot else! Translation? Less energy loss, more efficiency, and a much nicer looking electricity bill!
How can just one light create over 16 million different colors?
And what about all the different lighting options that high-quality smart bulbs offer the more aesthetic-minded consumers nowadays? How do manufacturers pull that off?
Well this one is actually simpler than you might think. The entire spectrum of visible light that we can pick up with our eyes can be reproduced by the interaction of three colors: red, green, and blue. Anyone out there who has ever fiddled around with their TV’s color settings may have noticed this fact before as you can change the levels of each to create any hue you want.
In a color-changing LED bulb then, each bulb contains three different kinds of colored diodes made up of red, green, and blue. When red combines with blue, you get magenta. Red and green creates yellow (light combinations are different than paint combinations!), and blue with green gives off cyan.
While the interaction between these colors alone can create a wide range and variety of different hues, you still can’t get to 16 million color choices just from these six. And that’s where brightness levels come in. If, say, red is combined with blue but the red light is only displayed at 50% brightness, you get a color in between magenta and blue.
You can see, then, how all of these different variables can add up to one truly versatile color palette that will give you more lighting choices than you’ve ever dreamt of!
How does an LED actually dim and brighten?
Back in the early days of LED development, you may have heard about LEDs being incompatible with dimming switches. And while this inconvenience was definitely true of LEDs at one point, they’ve come a long long way since then. In fact, most smart bulbs today offer not only compatibility with dimmer switches but also the ability to dim these neat little bulbs directly from your smart device. So, what changed between now and then?
The key difference between modern smart bulbs and the LEDs of yore is the implementation of either pulse-width modulation (PWM) or constant current reduction (CCR) which also goes by analog dimming.
PWM is basically an incredibly quick activation and deactivation of the lighting element. So instead of the LED staying on constantly, it achieves a dimmer appearance by quickly turning off and then back on. And while you may be thinking, “why doesn’t it look like they’re blinking?” the answer is that it all happens so quickly that the human eye can’t detect the individual blinks because they’re so fast. Instead, our eyes take the average light levels of the process, making it look like the bulb is actually dimmer. And when you make it even dimmer, that just means the light is turning off more often in any given second. Ingenious solution!
CCR is another method to dim certain LEDs and consists of reducing the power of the current fed to the bulb. This is the traditional method to adjust a bulb’s brightness but only recently have we been able to apply it to LED bulbs.
Combine it all together to create a smart bulb!
Put it all together and throw in a WiFi signal receiver and a microcomputer and you’ve got one of the most technologically advanced pieces of equipment in the home section today: the smart bulb!
Let us know what you think!
What kinds of questions or comments do you have about the anatomy of a smart bulb? Let us know in the comment section below and see the amazing technological achievements that are smart bulbs firsthand at the Flux Smart product section!