A chiclet keyboard, or island-style keyboard, is a type of input device for
electronic systems such as personal computers, calculators and remote
controls that uses keys in the shape of small squares with rounded corners and
straight sides, in the style of Chiclets gum. A perforated bezel fills the gaps
between the keys. The term has changed meaning in recent
years. During the first home computer boom of the 1980s, a chiclet keyboard
was synonymous with cheap quality and a poor user experience. Nowadays, the term
is neutral and refers low-profile, low-travel keyboards with simplified,
flat bezel-separated keycaps that other than their appearance function like
contemporary computer keyboards. History
The keys on Sinclair ZX Spectrum computers were "rubber dome keys" which
were sometimes described as "dead flesh", while the TRS-80 Color Computer,
TRS-80 MC-10, and Timex Sinclair 2068 were all described as having "chiclet
keys". The feel of the IBM PCjr's chiclet keyboard was reportedly compared
to "massaging fruit cake". Its quality was such that an amazed Tandy executive,
whose company had previously released a computer with a similarly unpopular
keyboard, asked "How could IBM have made that mistake with the PCjr?"
The term has changed meaning in recent years, and is now used to describe
low-profile, low-travel scissor keyboards with simplified, flat keycaps
separated by a bezel. Sony was the first modern laptop manufacturer to make use
of this keyboard style with the release of the VAIO X505 in 2004. Apple was
likewise among the first to change the design of its keyboards to the chiclet
style, with the release of the MacBook in 2006, and is credited with
popularizing the style. Design
The underlying technology used by such keyboards varies considerably. In some
cases the keys themselves are integral to the backing membrane and deform when
pressed to complete an electrical contact, while in other cases the keys
have individual low-travel scissor switches.
In some versions of the chiclet keyboard, the bottom three layers are
essentially the same as those in the membrane keyboard. In both cases, a
keypress is registered when the top layer is forced through a hole to touch
the bottom layer. For every key, the conductive traces on the bottom layer
are normally separated by a non-conductive gap. Electric current
cannot flow between them; the switch is open. When pushed down, conductive
material on the underside of the top layer bridges the gap between those
traces; the switch is closed, current can flow, and a keypress is registered.
Unlike the membrane keyboard, where the user presses directly onto the top
membrane layer, this form of chiclet keyboard places a set of moulded rubber
keys above this. With some key designs, the user pushes the key, and under
sufficient pressure the thin sides of the rubber key suddenly collapse. In
other designs — such as that seen in the diagram — the deliberate weak point is
where the key joins the rest of the sheet. The effect is similar in both
cases. This collapse allows the solid rubber center to move downwards, forcing
the top membrane layer against the bottom layer, and completing the
circuit. The "sudden collapse" of the chiclet keyboard provides a greater
tactile feedback to the user than a simple flat membrane keyboard.
= Simplified Design= Other versions of the chiclet keyboard
omit the upper membrane and hole/spacer layers; instead the underside of the
rubber keys themselves have a conductive coating. When the key is pushed, the
conductive underside makes contact with the traces on the bottom layer, and
bridges the gap between them, thus completing the circuit. Grooves between
hollow domes on the underside permit air to flow out of a dome when a key is
pressed, and let air come back in when released.
The dome switch keyboards used with a large proportion of modern PCs are
technically similar to chiclet keyboards. The rubber keys are replaced
with rubber domes, and hard plastic keytops rest on top of these. Because
the keytops are wider than the rubber domes the keytops are not separated but
align almost perfectly with only a minimal gap in between each other.
List of early computers with chiclet keyboards
All of the computers listed hail from the early home computer era, except the
OLPC XO-1. See also
Keyboard technology References
This article is based on material taken from the Free On-line Dictionary of
Computing prior to 1 November 2008 and incorporated under the "relicensing"
terms of the GFDL, version 1.3 or later.