Browse Prior Art Database

Keyboard Overlay Change Indicator

IP.com Disclosure Number: IPCOM000049051D
Original Publication Date: 1982-May-01
Included in the Prior Art Database: 2005-Feb-09
Document File: 1 page(s) / 12K

Publishing Venue

IBM

Related People

Flinders, M: AUTHOR

Abstract

Many hundreds of thousands of keyboard-operated video display terminals are in use around the world. The range of applications for which any particular terminal may be used is widening. A keyboard, which has the functions of the keys engraved or printed on the keytops, is an inflexible device and various ways have been tried to improve its flexibility. One particular way is the use of keyboard overlays which surround the keys whose functions change according to the mode of operation of the terminal. This article describes a way of signaling to an operator and to the system that the correct overlay for a particular terminal application is in place on the keyboard.

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Keyboard Overlay Change Indicator

Many hundreds of thousands of keyboard-operated video display terminals are in use around the world. The range of applications for which any particular terminal may be used is widening. A keyboard, which has the functions of the keys engraved or printed on the keytops, is an inflexible device and various ways have been tried to improve its flexibility. One particular way is the use of keyboard overlays which surround the keys whose functions change according to the mode of operation of the terminal. This article describes a way of signaling to an operator and to the system that the correct overlay for a particular terminal application is in place on the keyboard.

A hole or a series of holes is provided in the cover of the keyboard adjacent the keypad which has the overlay. Beneath each of the holes in the keyboard cover is an optical sensing unit consisting of a lamp and a light sensing device, such as a photo transistor, plus circuitry to indicate to the system whether the sensor is illuminated and to drive an audible alarm.

The overlay has a small patch of reflective material, such as aluminum foil, stuck onto the back of the overlay. This patch is aligned so as to cover one or more of the holes in the keyboard cover. The overlay may be reversible in which case it will have a strip of reflective material on each side, or there may be a series of overlays each having a patch of reflective material on the back arranged to align w...