Browse Prior Art Database

Pressure-Sensitive Trackball Device

IP.com Disclosure Number: IPCOM000116556D
Original Publication Date: 1995-Oct-01
Included in the Prior Art Database: 2005-Mar-30
Document File: 4 page(s) / 153K

Publishing Venue

IBM

Related People

Droge, D: AUTHOR [+6]

Abstract

A computer input pointing device is disclosed that enables the user to move the cursor on a computer display by applying both movement and pressure to the pointing device. In addition, the presence of pressure is used to activate the computer keyboard for a combination of uses, such as the right and left mouse selection buttons. The presence of pressure is also used to activate software controlling the size, shape and color of the display cursor. Lack of pressure is used to put the computer in a sleep mode.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 37% of the total text.

Pressure-Sensitive Trackball Device

      A computer input pointing device is disclosed that enables the
user to move the cursor on a computer display by applying both
movement and pressure to the pointing device.  In addition, the
presence of pressure is used to activate the computer keyboard for a
combination of uses, such as the right and left mouse selection
buttons.  The presence of pressure is also used to activate software
controlling the size, shape and color of the display cursor.  Lack of
pressure is used to put the computer in a sleep mode.

      A typical embodiment on a notebook computer is now described.
The front vertical edge of a normal notebook computer is slanted
inward toward the keyboard approximately 15-20 degrees from vertical
over a 3-4 inch area in the front center.  The degree of slant fits
the angle of a normal user's thumbs when placed on the front vertical
face of the notebook computer while the other fingers are placed on
the keyboard home row in a touch typing position.

      A minature trackball, approximately 1/2 inch in diameter, is
placed in the slanted area centered from side-to-side, but near the
top edge of the slant where the user's right or left thumb can be
comfortable placed on the trackball.  Approximately 45 percent of the
trackball is protruding from the slanted surface allowing the
trackball to remain in a captured position by methods commonly used
in today's technology.  The trackball is mounted in a standard
mechanism with electronics that converts rotational movement of the
trackball to cursor movement on the computer display and positional
information for the computer to use when an item is selected via the
normal "click" buttons.

      Under the standard mechanism holding the trackball is a thin
base material having a solution of pressure-sensitive ink contained
between outside layers which changes resistance according to the
applied pressure.  This resistance change is then processed by a
special electronics circuit which converts pressure to digital
thresholds which are processed by the computer or a later stage of
pointing device electronics.  Pressure sensor technology of the type
discussed above is demonstrated in products sold by Tekscan
Corporation.  The thickness of the pressure sensor is approximately
0.100 inches.  The electronics are designed to create the same
signals that the typical mouse driver software would receive in
today's technology with the exception that increasing pressure would
increase the rate of these signals and potentially, provide a new
signal which could be processed by the computer software to control
the cursor and keyboard characteristics as described below.

      The computer does not respond in any way to user-induced
trackball movements or pressure so long as the pressure is below as
predetermined level named here as the activation threshold Once the
activation threshold of pressure is reached, the computer switches
from...