The Computer Keyboard: A Physical Link to the Virtual World
Abstract: As technology has evolved, our methods of interacting with the virtual world have
changed and expanded. Yet the humble computer keyboard remains. How does the progress of
the computer keyboard reflect on technology as a whole? And what will it mean for technology
moving forward?
Key words: technology, keyboard, computer, interface, key, typing, history
Author Bio: Garrison Crouch is a junior majoring in chemical engineering, with an emphasis in
nanotechnology. Garrison has always had an interest in computers and technology, first
experiencing the internet through dialup on a used laptop with a black-and-white screen running
Windows 3.1. After working at Broadcom Corporation, he gained an appreciation for electrical
engineering, and is taking many electrical engineering classes alongside his chemical
engineering coursework.
Prepared on: 2/25/13
Prepared for Illumin Magazine
Sometimes a technology deserves to go the way of the dodo: consider fax machines, dialup modems, and floppy disks. As technological progress speeds on, many technologies have
been left behind. One basic technology has miraculously survived: the computer keyboard.
Though the basic design and concept is still more than a century old, we still use keyboards
every day as a physical method of creating and manipulating data in the virtual world. Keyboards
can impact daily life in a number of ways, and even harm unsuspecting users just looking for a
Facebook fix. As computers have evolved, so have our ways of interacting with them, including
the humble keyboard.
Early keyboards, found on mechanical typewriters, are marvels of pre-computing
engineering. They comprised hundreds of metal parts that transformed the downward motion of a
keystroke into the movement of an ink-laden metal character toward the correct spot on a piece
of paper. In effect, they were an evolution of the printing press, combining the idea of pre-cast
letters with the ease and spontaneity of writing by hand. Many of the early typewriters were
ornately detailed, and were considered by their users to be true writing instruments. Now, it is
hard to imagine writing an entire novel without even the use of spell check, but to writers at the
time, it was a drastic improvement over simple pen and paper.
Fig. 1: Image of the Crandall New Model typewriter from 1886, an early example of
the QWERTY keyboard layout on a mechanical typewriter. The Crandall is notable for its
mother-of-pearl decoration, as well as its innovative typeset mechanism. [2]
The legacy of the typewriter is still felt in nearly every computer keyboard. The nearly
ubiquitous QWERTY key layout, whose name corresponds to the first six letters of the top row
of letter keys, was designed to place frequently-used letters away from each other, so that fast
typists would not inadvertently crash the typewriter’s bars together. [2] This origins of this
layout have been the subject of some myth and legend in computer and technology circles,
including a rumor that the QWERTY layout was designed to “slow down” typists. In actuality, it
was designed to speed them up – by avoiding collisions of the letter bars – and has proven to be
as good as any alternate layout. [3] And so, the QWERTY layout remains.
Early computer keyboards, such as IBM’s now-defunct Model M, also embraced their
typewriter roots in their construction. In the 1980s, IBM developed the Buckling Spring switch
specifically for computer keyboards. This design uses a spring underneath each key that deforms
when the key is pressed and allows a small conductive bar to contact two electrodes, completing
a circuit and causing the keyboard controller circuit to register a keystroke. [4] This design was
robust enough to withstand millions of activations without failure, and provided both tactile and
audible confirmation of the keystroke: at the exact time the switch deforms and makes contact, a
change in the resistance of the key is felt, and a clicking sound is heard. [5] In a similar way,
computers of the time were largely mechanical. Punch cards, index card-sized piece of cardstock
with holes punched in special patterns, were used to write programs, and data was stored on large
spinning reels of tape. [6]
Fig. 2: Image from a patent for the buckling-spring keyboard switch [5] showing the key,
curved spring, contact, and keyboard base. The spring (2) bends when the key is pressed, removing
pressure from the pivot bar (7) so it completes the electrical circuit (5A and 5C)
The Model M was designed in a pre-PC era, when the keyboard was the predominant
computer input device for room-filling mainframe computers. Since these enormous computers
were so expensive, the cost of the keyboard and its individual switches was comparatively
negligible. As the focus of computing evolved from mainframes to desktop-sized devices
inexpensive enough for ordinary people and businesses to afford, the cost of the keyboard
became a much larger issue. The membrane switch was developed as a way of lowering cost as
well as decreasing the sound level of keyboards--a selling point in promotional material of the
time. In this design, a single membrane sheet with raised “bubbles” is placed along the entire
keyboard. Keys are positioned above each bubble, so when the key is pressed, two conducting
layers to come into contact, completing the key circuit, after which the membrane “bubble”
provides the force to return the key to its original position. Depending on the specific
construction of the bubble, this type of switch provides little to no tactile feedback and makes
almost no noise. [7] Though originally seen as an improvement to the keyboard, these attributes
would later prove detrimental to both usability and users’ comfort.
Fig. 3: Image showing a “rubber dome” type of membrane switch on a computer
keyboard. The small electrical connections between embedded in the membrane layers can
be seen as light, gold-colored lines. [7]
Then, in 2007, the computing industry changed when Apple introduced the iPhone. [8]
This remarkable device, and many other since, have spurred the evolution of the computer from
the more appliance-like machines of laptops and desktops, to an every-present, portable device
with many new functions and applications. Ways of interacting with these devices needed to
evolve as well. The iPhone’s unique user interface leveraged a capacitive multi-touch screen in
nearly all interaction with the user. A “virtual keyboard” provided a means for text entry. In this
style of “keyboard,” the keys are merely icons on a screen equipped with a metallic grid, usually
made of indium tin oxide, a unique metal that is both conductive and transparent. [9] A digitizer
chip monitors the grid’s capacitance, or ability to store a charge. The user’s skin emanates a
natural bioelectric field, which changes the local capacitance in the grid where the user touches
the screen. The digitizer chip then calculates a set of X-Y coordinate data from the position of
the change in capacitance, which the phone then matches to a specific button on the
keyboard.[10] Since there are no actual buttons, there is no tactile feedback or audible noise,
save for the light tap of the finger on glass.
Designers quickly realized that this lack of feedback was causing a problem with the
user’s experience of the keyboard. The lack of keys meant that the user needed to constantly look
at the virtual keyboard while typing in order to move the correct finger to the correct key, instead
of typing by feel. Since there was no feedback whatsoever, users could only tell if they pressed a
key when they saw the appearance of the letter on the screen, which meant that they had to look
back and forth from different parts of the screen. This was very tiring over long periods of use
and significantly decreased the quality of the user experience.
To overcome these problems, engineers and designers worked together to come up with
many inventive solutions. The simplest of these was to have the phone emit an audible “click”
each time a keypress was registered. While effective, this fake-sounding click was considered
annoying by some [11] and did not help in loud environments or with those hard of hearing.
Designers attempted to replicate some of the tactility of a real keyboard in the form of haptic
feedback, where a vibration motor underneath the screen pulsed when a keypress was registered.
This approach was relatively successful; studies show that users make fewer typing errors and
enter longer periods of text on screens with tactile feedback than on screens without. [12]
Meanwhile, mainstream computer keyboards have continued to decrease in tactility with
the move toward more mobile computing devices. As laptops continue their struggle to become
ever thinner, designers decrease the space relegated to the keyboard and request ever-thinner
switches from engineers. These keyboards cannot provide the same level of tactile feedback as
thicker keyboards simply due to the small distance that the key can travel. In reviewing one
especially thin laptop, a respected internet journalist stated that using the keyboard made her
hands feel tense and uncomfortable, like the way one’s feet feel when wearing flip-flops instead
of shoes: “When you’re wearing [flip-flops], which lack any kind of heel or arch support, you
might notice your toes rolling into a claw. They push into the flip-flop, gripping the rubber to the
extent that there’s anything to grab. With [this] keyboard, too, the keys are so short that there
isn’t much to latch onto.” In comparison, “[w]ith bigger, more tactile keys[…] our hands fly over
the keyboard – they don’t tense up because the buttons are simply easier to press.” [13]
So, instead of looking at a keyboard simply as an input device, how does it relate to the
user? After all, a keyboard is one of the few points of interaction between the user and the virtual
world. A well-designed keyboard can make the computing experience pleasant and engaging. A
poorly-designed keyboard, however, can cause repetitive-motion injuries such as carpel tunnel
and tendonitis. These ailments can be very hard to treat, a fact which this author knows well,
once even losing the use of three fingers for a length of time due to overuse of a computer
keyboard and piano.
Part of the ergonomic problem with computer keyboards is the shock experienced by the
fingers and joints when the key slams into the base of the keyboard, but this can be mitigated to
some extent by the design of the keyboard. On a membrane-based keyboard, the keypress is only
registered when the key can squish the two membrane layers together at the very bottom of its
travel. However, on a mechanical switch-based keyboard, the keystroke is registered while the
key is still being pressed, before it makes contact. In fact, on a keyboard with mechanical
switches, the key never needs to make contact with the bottom of the keyboard at all. This lack
of harsh contact and corresponding shock to the joints and tendons reduces the strain and risk of
injury to the user’s hands.
Recently, mechanical keyboards have seen a renaissance in the marketplace. Specialty
keyboard manufacturers have introduced mechanical keyboard models aimed at power users and
serious typists who have strong preferences about the feel of their keyboards. These keyboards
tend to be more costly – even “inexpensive” mechanical keyboards can retail for nearly $100,
compared to only $5 for a membrane-based keyboard. These keyboards give the user some
physical response and feeling when interacting with computers, but they are limited to desktop
computers and can do little to help the typing experience on more mobile devices, such as tablets
and smartphones.
To help with this problem, research is being conducted to improve the tactility of virtual
keyboards. One such project involves bonding a membrane layer to the exterior to the screen that
is imprinted with bubbles. When the user opens the virtual keyboard, a small electrical current is
passed through the membrane in the areas over the “keys”, which causes a fluid to increase in
pressure and push the membrane extend away for the surface slightly. The user can feel these
bumps with their fingertips, helping them place their fingers over the virtual keyboard more
accurately. This amazing technology has even been demonstrated on working mobile devices,
and may even become commercially available by the end of this year. [14]
http://www.youtube.com/watch?v=JelhR2iPuw0 [I would like to embed this video
somehow in the online Illumin article, but Word won’t seem to let me.]
But what if keyboards were not even necessary in the future? One trend in computing
technology revolves around “aware” devices that aggregate data from many different sources,
including GPS, accelerometers, e-mails and calendar appointments, enabling the computer to
predict what the user will want, without needing any text input. Projects like Google Glass take
this concept one step further by integrating the display onto the user’s glasses, and relying on a
gesture-based input device for direct user interaction. These advancements in computing
technology, as well as improvements in speech recognition, decrease the need for a keyboard
more than at any other point in the evolution of computers to date. [15]
Looking further into the future, technologies such as neural interfaces may seem
promising. Though currently relegated to simple games or laborious cursor movements, it is
possible that computers may one day be able to translate our thoughts into text. [16] Unlike a
conventional keyboard or physical input device, however, the rate of data input into the computer
may not be limited by the conscious mind’s control of a physical object. Such capability would
have far-reaching effects, both ethical and technological. Issues may arise if, for example, a
“neural-interface keyboard” could interpret a users’ brainwaves to predict what he or she were
thinking before the user was consciously aware of the thought, and some harmful action was
taken autonomously by the computer, affecting users’ lives in completely new ways. At the
current rate of technical progress in this area, though, such issues will not be a reality for many
years to come.
Even with these advancements, it seems unlikely that the computer keyboard will
disappear entirely. This device, honed over decades of use by millions of people, is a very
efficient and reliable means of text entry, allowing practiced users typing speeds of more than a
hundred words per minute. Even the QWERTY layout has survived nearly a century of
technological change. From typewriters, to mainframes, to PCs, to smartphones and tablets, the
computer keyboard still lives on. Though future advancements in user interfaces may decrease
the need for a keyboard, if history is any guide, the keyboard will be adapted and changed to
meet our needs as we continue to interact with our computers and the world around us.
References
[1] Costa Collection, Crandall New Model [Online] Available:
http://www.typewritermuseum.org/
[2] D. Rehr, Why QWERTY was Invented [Online] Available:
http://home.earthlink.net/~dcrehr/
[3] S. J. Liebowtiz and S. E. Margolis, “The Fable of the Keys,” J. of Law and Econ. vol.
30 no. 1 pp 1-26, April, 1990.
[4] R. H. Harris, “Buckling Spring Torsional Snap Actuator,” US Patent 4,118,611 Oct.
3, 1978.
[5] ClickyKeyboards.com. Index. [Online]Available: http://www.clickykeyboards.com/
[6] IBM.com, IBM100 – The IBM Punched Card. [Online] Available:
http://www-03.ibm.com/
[7] J. Tyson and T. V. Wilson, How Computer Keyboards Work. [Online] Available:
http://computer.howstuffworks.com
[8] S. Segan and T. Gideon, (Jan. 22, 2008) “Apple iPhone,” PC Mag., [Online]
Available: www.pcmag.com
[9] P. Patel-Predd, (Jan. 2009) “The Trouble with Touch Screens,” [Online] IEEE
Spectrum. Available: http://spectrum.ieee.org/
[10] T. V. Wilson and W. Fenlon, How the iPhone Works. [Online] Available:
http://electronics.howstuffworks.com/
[11] C. Oldroyd, Daily Tip: How to disable keyboard clicks when inputting text. [Online]
Available: www.imore.com
[12] S. Brewster, F. Chohan, L. Brown. “Tactile Feedback for Mobile Interactions,” in
CHI 2007, San Jose, CA, 2007, pp. 159-162.
[13] D. Wollman (2011, Jul. 29). Sony VAIO Z Review [Online] Available:
http://www.engadget.com
[14] A. Strange, (2012, June 8). “Tactus Unveils Physical Keyboard for Touch-Screen
Displays.” PC Mag., [Online] Available: www.pcmag.com
[15] D. Melanson, (2012, May 30) “Google’s Steve Lee talks about the history and future
of Project Glass” [Online] Available: http://www.engadget.com
[16] C. O’Brien, (2013, March 8) “Mind games: Using brain waves to play a video
game” [Online] Available: http:///www.latimes.com