Electronic Design

From The Typewriter To The PC And Beyond

The QWERTY format has seen 134 years of evolution. So, what key innovations will make an imprint next?

Patented in 1869 by Milwaukee newspaper editor Christopher Sholes with partners S.W. Soule and G. Glidden, the first typewriters went into production at Remington Arms Co. in 1873. Essentially, they were word processors without a display or memory. They also were unforgiving in terms of user-input errors, since they lacked spellcheck or even correctable tape. Yet the typewriter is notable for its alphanumeric layout (Fig. 1).

Sholes first arranged the keys in rows with the letters in alphabetical order from left to right. This required many often-used letters on the end of thin metal bars that impact the paper to be next to each other. When a typist got up to speed, the bars would frequently tangle up with each other. Rectifying this in 1874, Sholes rearranged the letters so the bars would strike the paper from different directions.

This new layout, known as the QWERTY design because they are the first six letters of the keyboard’s top row, has been with us ever since. Rarely used now, the typewriter became an indispensable business tool in its day and has undergone a logical evolution from a purely mechanical unit to electromechanical to standalone word processors. However, its user-input component, the keyboard, lives on as an indispensable accessory for today’s most powerful tool, the computer, as well as myriad other components and systems requiring alphanumeric input from humans.

The QWERTY keyboard survives most commonly in the form of keyboards for desktop and laptop computers. Yet the technologies behind these keyboards and their variations are most likely beyond anything the inventors of the typewriter could have foreseen.

VARIATIONS ON A THEME
Virtual keyboards may primarily address disabled users who can’t work with physical keyboards, but they’re catching on with portable- product users and gamers. They consist of software and/or additional hardware to create a functional, though non-mechanical, replica of the keyboard. This replica could be a light projection of the keyboard onto a convenient surface, i.e., the desktop. Or, it could transform the monitor or LCD into a touchscreen.

The CL800BT system developed by Korean company Celluon uses a red laser diode to project a functioning QWERTY keyboard image measuring approximately 240 by 105 mm onto a non-reflective, opaque flat surface (Fig. 2). The keyboard is visible in ambient light ranging from 1000 to 5000 lux, and it provides an effective keystroke distance of 2 mm. In terms of detection rate, users may type at speeds up to 400 characters per minute.

Powered by an integral lithium-ion (Li-ion) battery, the system’s red-laser projector module measures 93 by 39 by 37 mm and weighs 109 g. It interfaces with a PC or portable device via the RS-232C protocol. Compatible operating systems include Windows 2000/XP/ Vista/Mobile Pocket PC & Smart Phone, plus Palm OS, BlackBerry, and Symbian.

Eyeing users with mobility impairments, tablet PC users, video-game developers, and manufacturers of machine tools, medical equipment, and point-of-sale kiosks, the Touch-It software utility from Swiss company Chessware SA displays a keyboard on the computer monitor, turning it into a working touchscreen. In addition to mimicking a standard QWERTY keyboard, the application includes tools for creating keyboards via preset templates or unique layouts from scratch (Fig. 3).

Operating with Windows 2000/XP/Vista/ Server 2003, Touch-It supports all of the languages in Windows’ input settings as well as language switching. Developers can address Touch-It from a third application through Windows messages or the COM interface. It can also send Windows messages to developers’ applications, invoke callback procedures into their libraries, or call COM methods.

Furthermore, Touch- It can make keyboards appear on the edge of the screen and behave like application bars. Its typing rates and delays match those set by users in Windows. It offers multimonitor and alpha-blending support. And, it can load user libraries in the Touch-It environment and manage callbacks in real time.

TOUCHSCREEN TRENDS
In most applications, from commercial to industrial and portables, touchscreens have replaced keyboards and mechanical buttons— and with good reason. They’re reliable and easy to use. Also, they’re nearly vandal-proof. They aren’t subject to the wear and tear resulting from repetitive actuations, and they’re resistant to liquids. Naturally, development in this area is rather strong.

Patented in Japan in April, Neonode’s zForce touchscreen technology eliminates the need for a stylus or keys for user input in a range of portable products. The Swedish mobile-phone company’s technology relies on photodiodes and LEDs to provide a sunlight-visible display. The photodiodes and LEDs accept stimuli from finger touches and sweeps and require very little pressure for response.

Continue on Page 2

According to Neonode, zForce requires few components and involves an easy, straightforward manufacturing process compared to more expensive, layered capacitive and resistive touchscreens. Featured in the Neonode N2 mobile phone, zForce is also viable in digital cameras, GPS products, and laptops (Fig. 4).

Known for its pen tablets and interactive pen displays, Wacom announced in April what it calls a major innovation in capacitive touchscreens. The patent-pending Reversing Ramped Field Capacitive (RRFC) touch technology employs unique low-power circuitry and reversing-ramped electrostatic fields to deliver pinpoint precision and drift-free performance. RRFC integrates into dual-input applications with the company’s EMR pen-input technology for Tablet PC OEMs, or it can operate standalone on other platforms requiring just a finger-touch interface.

“RRFC’s controller processing methods and system design provide extremely accurate pointing at much lower power consumption levels and without increased cost,” says Shawn Gray, Wacom’s director of touchscreen operations. “These factors and others, such as ease of integration and stability, position RRFC touch as a natural alternative to resistive, surface acoustic wave, and infrared touch technologies.”

Compared to resistive capacitive touchscreens, Wacom says, RRFC boosts transmissivity up to 95% and requires significantly less pressure to activate. In addition, the company says the RRFC touchscreen is tougher than glass, virtually eliminating wear and scratching.

Targeting broadcasters and users working in multi-viewer applications where space is limited and video sources numerous, the Touch-it Digital multichannel video monitor and controller from Wohler Technologies teams up adjacent 7-in. color LCDs in 3RU of space. The unit provides real-time monitoring and routing of up to 16 channels of multirate HD/SD-SDI video.

The LCD on the left in Figure 5 is a touchscreen that displays from four to 16 thumbnail images, all of which automatically scale to fill the screen. Touching one of the thumbnails transfers the image to the LCD on the right.

The HD/SD-SDI source signal becomes available on the system’s binary network connector (BNC) outputs. Also, a BNC output for the touchscreen lets users view the thumbnails on an external display if necessary. “The unit offers versatile, full-screen resolution viewing of any video source with a single tap to the screen, making it easy for operators to select and focus in on any of 16 HD/SD-SDI mixed inputs,” says Wohler president and CEO Carl J. Dempsey. “Of note, the Touch-it Digital supports field upgrades for any emerging features and functions over the life of the unit.”

Also gaining momentum in applications from medical to gaming, TouchSense technology from Immersion makes buttons on a touchscreen feel like their mechanical counterparts. A touchscreen controller imparts input and location to a software application that transmits the desired tactile effects to a proprietary TouchSense controller, which vibrates the touchscreen at various frequencies using different wave shapes, levels, and durations.

The application software determines the particular tactile feel of each button on the screen. It also allows the individual programming of each button, giving each a unique feel. Synchronizable with sounds and images, the technology is compatible with flat-screen sizes ranging from 2 to beyond 19 in. and supports a range of standard sensors. For portable products, TouchSense Mobile employs a TouchSense executable and handles touchscreen sizes up to 15 cm diagonal.

Late last year, Tyco Electronics enlisted AMI Semiconductor to develop a chip that would allow Acoustic Pulse Recognition (APR) touch technology to be ported from Tyco’s Elo Touch Systems group into handheld applications, such as cell phones and GPS units. APR borrows from a number of existing touch technologies and provides an alternative to capacitive and resistive implementations. APR, which is audiobased, recognizes sounds created when the screen is touched at a preset position. This approach accurately detects input via finger, fingernail, gloved hand, or stylus. The technology also includes palm rejection functionality.

There appears to be no news of progress on AMI’s chip, which has since come under the umbrella of ON Semiconductor. Yet there’s no slowdown in the development of APR-based products. Earlier this year, Tyco introduced the Elo 17A2 touch computer sporting a 17-in. touchscreen LCD (Fig. 6). Groomed for the point-of-service market, this computer with dual-display capability offers a choice of the company’s touch technologies: AccuTouch Five-Wire Resistive, IntelliTouch Surface Wave, CarrollTouch Infrared, and/or APR.

In addition to the 17A2 LCD’s SXGA resolution and 5-by-4 aspect ratio, the system features a 1-GHz Celeron M processor with a 400-MHz front-side bus (FSB), up to 1.5 Gbytes of DDR2 RAM, a mini-PCI slot, two serial and four USB 2.0 interfaces, and one Ethernet port. Operating-system support consists of Windows XP Pro/XP Embedded/Vista Business.

WHAT ABOUT SPEECH RECOGNITION?
We don’t hear too much about speech recognition, the technology that may have completely sent the mechanical keyboard to recycle-land. It’s employed extensively in commercial telephone applications, i.e., customer service calls. But despite the improvements in many available consumer and business applications, it hasn’t entered the mainstream yet.

Speech recognition has failed to catch on for a number of reasons. Some applications require users to speak literally rather than naturally, pronouncing punctuation marks and symbols. In many cases, users have to teach the program any special characters, phrases, acronyms, and other language peculiarities. Also, in a populated office with numerous cubicles, speech recognition is impractical. Imagine several coworkers in adjacent cubicles speaking to their computers simultaneously. So until some breakthroughs happen, don’t throw out those QWERTY keyboards.

Hide comments

Comments

  • Allowed HTML tags: <em> <strong> <blockquote> <br> <p>

Plain text

  • No HTML tags allowed.
  • Web page addresses and e-mail addresses turn into links automatically.
  • Lines and paragraphs break automatically.
Publish