Musings on optics, physics, astronomy, technology and life

Posts tagged ‘LEDs’

Could your light bulb talk to you? (Update on Li-Fi)

A “talking light bulb” isn’t the product of some tin-hatted paranoiac — not if the light bulb in question is an LED model, and not if you’re using a Li-Fi signal in place of Wi-Fi.

What is Li-Fi, you may ask? Basically, it’s a type of optical wireless communications (OWC) in which a LED, not a radio-frequency router, gives off the signal that talks to your device. I wrote about it in this 2014 article for Optics & Photonics News. If you’d rather get your information by listening to it, researcher Harald Haas, who coined the term “Li-Fi,” gave a TED talk and demonstration about it in 2011.

Although that speech is four years old now, Li-Fi hasn’t made much of a dent in the marketplace … yet. Every wirelessly connected device you already own — smartphone, tablet, laptop, Fitbit, whatever — would need to have a second set of receivers and transmitters to communicate with Li-Fi as well as Wi-Fi “hot spots.” Still, it’s hard to imagine how the so-called “Internet of Things” will develop if we don’t increase the amount of electromagnetic bandwidth we use for communications — and Li-Fi would open up a lot of bandwidth for sure. Perhaps, in the not-so-distant future, flight attendants will hand out Li-Fi converters to airline passengers so that they can use their devices to communicate while traveling, the way they now hand out headphones (or used to hand out headphones, depending on your flight) and beverages.

Recently, Haas’ group, based out of the University of Edinburgh in Scotland, has figured out how to make organic solar cells into Li-Fi receivers as well as power sources. That’s cool, because in our quest to endlessly miniaturize our devices, we don’t leave a lot of real estate open for transmitters and receivers — or for additional battery packs, for that matter. If you’re truly interested in the technical details, you can find the original article here.

A slightly different, more marketing-oriented twist on Li-Fi technology is offered by a Boston-based company called ByteLight, which was recently acquired by another company called Acuity Brands. We shall see how that shakes out and how OWC will evolve over the next few years.

(P.S. Please, can we come up with a better phrase than “Internet of Things”? That sounds way too much like the “information superhighway” you might have heard about back in 1990 or thereabouts.)

 

More on the light bulb controversy

The CLEO conference blog has reprinted an entry by James Van Howe, of “Jim’s CLEO Blog,” summarizing the controversy over the new lighting regulations and — helpfully — pointing out some sessions at CLEO 2011 that address the technical challenges of making LED lighting better for all of us to use.

Incidentally, CLEO 2011 will take place during the first week of May in Baltimore, about an hour’s drive from Our Nation’s Capital. I wonder whether any lawmakers are going to show up?