When thinking of image-based interaction, a touchscreen is the first thing that comes to mind. And while touchscreens are increasingly employed in contemporary product design, the primary means for navigating our high-tech world is still paddling through the stream of buttons found on keyboards, printers, remote controls, security systems, telephones, ATMs, vending machines, and more. Now there is a way to provide direct visual feedback for this button world – right on the button.

United Keys, San Jose, Calif., has developed a technology for embedding small displays onto the tops of pushbuttons or key switches and then controlling them. In essence, the technology is a means for driving multiple miniature displays attached to standard, electromechanical input devices – combining visual and tactile feedback into a single component.

The idea seems so simple and elegant, the obvious question is what took so long for someone to think of it. In fact, the concept has been employed selectively in the past, but mostly in expensive custom designs. The novelty of United Keys’ approach is to pull it off in an economical fashion that makes the concept affordable for high-volume applications, according to Ronald Brown, CEO.

Photoillustration of how game controller might use display keys.

There are several important factors permitting the company to deliver a cost-effective solution. One is that displays are now available in smaller and thinner sizes, and their costs have been declining. Another is the utilization of commonly available display and input devices, rather than custom-designed components. “At the component level, we are combining standard form factors that are already running off of high-volume assembly lines,” Brown says. “We don’t need a custom factory to build these.”

The means for manufacturing the product also contributes to its economics. Instead of trying to gradually build a manufacturing capacity, United Keys has formed a strategic alliance with Foxconn Technology Group, Taiwan, one of the world’s largest contract manufacturers of consumer electronics, a company already making products for many of the well-known consumer electronics brands. The partnership provides United Keys with immediate, established, high-quality, high-volume production capacity, allowing the company to market its technology to potential high-volume customers, something a small start-up company can’t usually attempt. If some OEM wants a million of these things, Foxconn and United Keys can make it happen.

Another aspect that supports cost-effective implementation is that the customizable features are achieved through software, as opposed to customizing the display-key itself. Like any other display device, the display on top of a key switch or pushbutton can display anything the OEM customer wants to feed it, dependent only on size restrictions. (The smaller the key, the smaller the display, the less information that can be conveyed.)

Given that the technology employs standard input devices, the OEM designer has the same options available as when choosing any other key switch or pushbutton in terms of actuation force, switch travel, sealing, and so on. The product designer has the same flexibility with display options – monochrome or full-color LCD, OLED, or whatever other display technology becomes available. And the display key could show anything an ordinary display would, from icons to images, and eventually even animation. (The display is covered by a durable, transparent cap that is designed to stand up to even the most vigorous use experienced by a game console.)

Cutaway photoillustration showing display embedded into top of key switch.

The United Keys technology can drive as many mini displays as specified by the OEM customer. For example, all of the keys on a standard computer keyboard could be enabled with displays if desired. This would allow the same physical keyboard component to display different characters for different languages, or would allow the same keyboard to display the common QWERTY layout or the alternative Dvorak layout, depending on a user’s preference.

The display keys could also be programmed to work in concert as segments of a larger image, with each one showing a piece of the overall image.

In actual practice, however, Brown sees most of his prospects interested in enabling a small number of keys that would change their content. The dynamic capabilities of the technology in effect reduces the number of keys that would need to be enabled.

Brown illustrates the point by using a remote control as an example.

“A remote control might have 40 different buttons on it to accommodate all of its functions. To make that easier to use, you would not need to enable all the keys with displays. What you would do is enable some of them so that they could display different things at different times, depending on what the user wanted to do. Intelligent software, that understands the context of the users desires, would dramatically reduce the number of static keys needed on the device itself.”

A mobile phone could use display keys to access special features.

Designers also have choices as to the source of content for the displays. The display keys can be driven by the software within a specific product application, by an internal, local area network, or even driven remotely by an Internet connection depending on the product designers’ wishes.

When used on a computer keyboard, for example, the user could be working in one application on screen while a display key shows a message from another application.

And because the display keys are software driven, the system can be easily customized to a specific application environment. For example, airlines, banks, hospitals, and retail chains, often have specialized software dedicated to their needs. Display keys on computer terminals in such environments could be used to show information unique to that specific use.

The software-driven display keys could also allow the upgrading of user-interfaces on appliances already in the field. For example, a fast-food chain typically has cooking or reheating appliances with buttons dedicated to specific menu items, each of which selects a heating program specific to that item. This eliminates the need for a fast-food worker to set time and temperature controls. When menu items change, the appliance must be reprogrammed and the graphics for the buttons physically changed on each appliance at each location in the chain. By using an external network and display keys on its foodservice appliance, a fast-food chain could remotely upgrade the appliance’s program and legends simultaneously throughout its entire network of outlets.

Incorporating display keys into networked devices would also benefit the casino industry, which is currently moving away from standalone CPUs in electronic games to server-based systems.

Display keys on a remote control could help simplify its use and appearance.

The interactivity provided by visual feedback on a tactile input device provides a new way to make selections in menus and sub-menus in computers. This could help eliminate the need for a computer mouse in situations where the use of a mouse is impractical or inconvenient, such as airline terminals, medical devices, retail POS machines, multi-functional copy/print machines, and more.

Brown says that the use of display keys can also reduce input error rates in scenarios where information must be properly categorized, such as medical facilities or service call centers.

The type of information conveyed on a display is virtually unlimited. A self-service retail POS machine using the display keys might have them show advertising while the user is waiting for a transaction to process. One banking firm exploring the technology envisions it as a way to promote financial services while its customers are using an ATM.

Another obvious target area for display keys is the portable electronic device market, including cell phones and PDAs, where space constraints make the design of interfaces challenging.

United Keys’ first product to hit the market will be a computer keyboard with a cluster of nine display keys on the left side of the board.

Naturally, touchscreen suppliers are pursuing all of those markets as well, offering a different approach to image-based interaction. For similar applications, touchscreens are a more expensive solution than display keys, Brown says, and most touchscreens don’t provide tactile feedback.

“A lot of designers have tried to force a touchscreen solution onto a button world because it seemed to be the easiest means for implementing interactivity. But I think we have a more natural solution that is applicable to a broader range of products.”

That said, Brown does not envision one technology forcing out the other in the future.

“There are applications where touchscreens make sense, and there are applications where display keys make sense,” Brown says. “The two technologies will coexist.”

United Keys will roll out its first product, a computer keyboard, later this year. The board will have nine oversized keys enabled with displays, and they will be clustered as a pod on the left side of the board. The first version will have monochrome displays and be aimed at early adopters and design engineers looking to experiment with a new solution. A subsequent version of the keyboard will be more tailored for consumer needs and will have four-color displays. It is scheduled for introduction next year. The company will also be producing a developer’s toolkit.

Based on preliminary discussions with OEMs, Brown expects interest in display key technology to ignite once product designers become aware of its practical application and cost effectiveness. He says that, in a world with increasing product complexity, display key technology can simplify complex commands and make interactive products more engaging for the end user.

“We are taking an interactive technology that had been highly specialized and very expensive and simplifying it so that it becomes economical enough to address applications in virtually any industry.”