Patents: Amazon’s Clever Voice-Controlled Light Switch is not Just ‘Alexa Inside’

Amazon’s patent application for voice-controlled light switch describes multiple mics on the faceplate and switch itself, so it can respond based on the position of the speaker (user) and whether the light is on or off.


Amazon has filed a patent application for “voice-controlled light switches.” And no, it’s not just a smart light switch with a microphone, Wi-Fi and Alexa inside.

Instead, the patent application (#20170188437) describes a switch with multiple microphones on the faceplate and the switch itself, along with technology that allows the voice-recognition engine to respond based on the position of the switch.

Although the patent describes multiple form factors for the switch (toggle, paddle, slider, knob), let’s give an example of a traditional toggle.

There might be a mic on the tip of the toggle itself, as well as two mics on the top left and right of the faceplate, and two at the bottom left and right. When the switch is on (up), it aligns with the upper mics. When it’s off, it aligns with the bottom mics.

We can imagine how a house full of these smart switches could parse commands based on where the user is, and which switches (lights) are on.

Based on the alignment of the mics, the speech-recognition engine processes commands differently. For example, if the switch is off, it may be listening only for a wake-up word. In this way, the mics would not respond to commands such, as “What is the weather?”

If the switch is up (on), then its ears perk up, listening for a broad range of commands like any other Alexa device.

The technology involves changes in the signal-to-noise ratio to either increase or decrease the “listening” sensitivity based on the status of a switch.

There’s a whole lot of other stuff in the patent application, like directionality of the mics, that would suggest how a house full of these smart switches could parse commands based on where the user is, and which switches (lights) are on.

Oddly, the patent describes how the smart switch can control the attached load via voice, but that would seem to defeat the purpose: The toggle would then be stuck in the “wrong” listening position.

So if it doesn't make sense to use the technology to control the attached load, why not just give us a retrofittable faceplate with the same technology, plus a tiny mic that affixes to the toggle or paddle? It could be powered by touching conductors to the switch beneath, a la SnapPower.

In any case, I'm not sure we’ll be seeing a whole lot of toggle switches in our digital future, but still, the Amazon invention is pretty clever.

Flow chart: speech is processed based on the position of the light switch.

About the Author

Julie Jacobson
Julie Jacobson:

Julie Jacobson is founding editor of CE Pro, the leading media brand for the home-technology channel. She has covered the smart-home industry since 1994, long before there was much of an Internet, let alone an Internet of things. Currently she studies, speaks, writes and rabble-rouses in the areas of home automation, security, networked A/V, wellness-related technology, biophilic design, and the business of home technology. Julie majored in Economics at the University of Michigan, spent a year abroad at Cambridge University, and earned an MBA from the University of Texas at Austin. She is a recipient of the annual CTA TechHome Leadership Award, and a CEDIA Fellows honoree. A washed-up Ultimate Frisbee player, Julie currently resides in San Antonio, Texas and sometimes St. Paul, Minn. Follow on Twitter: @juliejacobson