Membrane keyboard
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A membrane keyboard is a computer keyboard whose "keys" are not separate, moving parts, as with the majority of other keyboards, but rather have only outlines and symbols printed on a flat, flexible surface. Very little, if any, tactile feedback is felt when using such a keyboard, and blind typing is practically impossible.
Membrane keyboards, which work by electrical contact between the keyboard surface and the underlying circuits when keytop areas are pressed, were used with some early 1980s home computers, and have been much used in consumer electronics devices. The keyboards are very inexpensive to mass produce, and are more resistant against dirt and liquids than most other keyboards, but due to the low or non-existent amount of tactile feedback provided, most people have difficulty typing with them, especially when large numbers of characters need to be typed. Chiclet keyboards were a slight improvement, at least allowing individual keys to be felt to some extent.
Aside from early hobbyist/kit/home computers and some video game consoles, membrane-based QWERTY keyboards are used in some industrial computer systems, and are also found as portable, even "rollable-collapsible" designs for PDAs and other pocket computing devices. Smaller, specialised membrane keyboards, typically numeric-and-a-few-control-keys only, have been used in access control systems (for buildings and restricted areas), simple handheld calculators, domestic remote control keypads, and other similar devices where the amount of typing is relatively small or infrequent.
List of computers with membrane keyboards
QWERTY layouts unless otherwise specified
- Atari 400 (full-travel replacement keyboards much like those that came with the Atari 800 were available)
- Cambridge Z88 (arguably a mix between a membrane and chiclet keyboard)
- Magnavox Odyssey˛, also known as the Philips Videopac G7000 video game console
- RCA COSMAC VIP, a do-it-yourself (DIY) kit computer with 16-key hex keypad
- SEGA SC-3000, a computer version of an early SEGA game console
- Science of Cambridge Microcomputer Kit 14 (MK14); the initial version had a 20-key extended hex keypad
- Sinclair ZX80, a pioneering British home computer that was available as a DIY kit
- Sinclair ZX81 (similar to the preceding entry)
- Synertek SYM-1, a sibling of the MOS/CBM KIM-1 with a 29-key extended hex keypad
- Timex Sinclair 1000 (a U.S. version of the ZX81)
See also: chiclet keyboard