feature article
Subscribe Now

Power Windows 2.0

Chromatic Glass Adds Embedded Intelligence to Construction

This week we’re going to talk about programming windows. No, I mean it. Literally, windows. As in, the glass outside your building.

Think I’m nuts? Then you haven’t met the people at View, Incorporated, the Silicon Valley–based company that makes “smart glass.” This isn’t the glass for your smartphone or tablet. It’s window glass, like you’d use for an office building, hospital, or hotel. We’re talking big sheets of glass – as much as 50 square feet. And they’re programmable.

Google Glass, meet Microsoft Windows.

View’s glass has adjustable transparency and adjustable thermal characteristics. At its simplest, it’s like a giant-sized pair of biofinity toric lenses for buildings. It can darken itself in response to bright sunlight, or go clear again when it’s dark out. It can block infrared radiation (i.e., heat) or transmit it, depending on your requirements.

The purpose of all this is twofold. First, it’s to make the building more comfortable for its inhabitants. Rather than drawing curtains or closing blinds when it gets too bright out, why not just have the windows darken themselves? It’s easier and it avoids installing 5,000 sets of blinds in a large building.

Second, it cuts down on heating and cooling costs. Instead of cranking up the industrial-sized air conditioner to battle the heat pouring in through the windows, why not have the windows themselves block most of the heat? If the heat never gets in, you don’t have to power big fans to pump it back out.

How’s it all work? Electronics. View has created an electrochromic coating that it applies to the inside of the window glass, which is then activated by a low-voltage charge. A nearby controller decides when it’s time to darken the glass and when it’s time to lighten them up again. There are four discrete degrees of tint, from clear to very dark, and the transition takes about 10–30 minutes, depending on the size of the glass. That sounds really slow, but changing any faster looks funny, both from inside and outside the building. Gradual changes in tint are less disconcerting and also more energy-efficient.

View, Inc. doesn’t license its technology, nor does it sell the magic coating to other manufacturers. Instead, the company has a more old-school business model and actually manufactures and sells its own windows under the name “Dynamic Glass.” Typical customers are architectural firms and large contractors – the kind of people who buy windows 1,000 at a time. There’s no DIY version at Home Depot… at least, not yet.

The process of coating the window glass is remarkably similar to semiconductor sputtering. In fact, View buys a lot of second-hand semiconductor equipment and re-engineers it for use in its manufacturing facility outside of Memphis. The company then purchases comercially available clear glass and runs it through its custom equipment. Several layers of metal oxide are laid down, to a total thickness of about a micron. Another sheet of glass is bonded on top of this, sandwiching the oxide between the two layers of glass. This protects the sensitive coating from scratches and provides better insulation, like a double-glazed window. The whole process isn’t too different from how LCD displays or thin-film solar panels are made – just way bigger.

Is the Dynamic Glass expensive? You bet. It’s more expensive than standard commercial glass, for obvious reasons. But it also saves on HVAC costs, enough so that it can sometimes pay for itself in a reasonable amount of time. Then there’s the savings on window blinds, curtains, shades, awnings, reflective coatings, air conditioning, heating, and so on. There are also intangible benefits. The darkened glass looks good, especially on bright sunny days. Customers seem to like it, and architects find it gives them a new option to play with.

Since each pane of glass can be controlled individually, you can go crazy with controllers for each window, creating a patchwork array of light and dark windows on a large building. More typically, however, you’d control a whole wall of windows at once, making the south-facing ones progressively darker as the sun rose, and clearing them up again in the evening. In between those extremes, you might control the windows in a large conference room separately from the rest of the floor, or darken the windows in unused offices. Naturally, there’s a smartphone app for the controller, proving once and for all that Apple and Android really do support windows.

Leave a Reply

featured blogs
Sep 27, 2021
Conduct full-lifecycle IC design reliability verification with PrimeSim Reliability Analysis, a chip design tool ensuring safety in SoC and IC applications. The post A Pioneering Approach to Safety: PrimeSim Reliability Takes Center Stage appeared first on From Silicon To So...
Sep 27, 2021
The latest release of the Tempus Timing Signoff Solution, 21.1, contains a lot of new capabilities. There are far too many to cover in a single blog post'”the customer presentation on Tempus is 90... [[ Click on the title to access the full blog on the Cadence Community sit...
Sep 24, 2021
Wi-Fi, NB-IoT, Bluetooth, LoRaWAN... This webinar will help you to choose the appropriate connectivity protocol for your IoT application....
Sep 23, 2021
The Global Environment Facility Small Grants Programme (GEF SGP), implemented by the United Nations Development Programme, is collaborating with the InnovateFPGA contest. Showcase your  skills with Intel Edge-Centric FPGAs and help develop technical solutions that reduce env...

featured video

Enter the InnovateFPGA Design Contest to Solve Real-World Sustainability Problems

Sponsored by Intel

The Global Environment Facility Small Grants Programme (GEF SGP), implemented by the United Nations Development Programme, is collaborating with the InnovateFPGA contest to support 7 funded projects that are looking for technical solutions in biodiversity, sustainable agriculture, and marine conservation. Contestants have access to the Intel® Cyclone® V SoC FPGA in the Cloud Connectivity Kit, Analog Devices plug-in boards, and Microsoft Azure IoT.

Learn more about the contest and enter here by October 31, 2021

featured paper

3 key design decisions for any desktop 3D printer design

Sponsored by Texas Instruments

Learn about three important design considerations to take your 3D print design to the next level.

Click to read more

featured chalk talk

TI Robotics System Learning Kit

Sponsored by Mouser Electronics and Texas Instruments

Robotics projects can get complicated quickly, and finding a set of components, controllers, networking, and software that plays nicely together is a real headache. In this episode of Chalk Talk, Amelia Dalton chats with Mark Easley of Texas Instruments about the TI-RSLK Robotics Kit, which will get you up and running on your next robotics project in no time.

Click here for more information about the Texas Instruments TIRSLK-EVM Robotics System Lab Kit