Kapacitiv tastaturlæser til blinde

Abstract

The present invention relates to a capacitive keyboard reader (1) comprising a one-piece front panel (2) made of dielectric material, the front panel (2) comprising at least one recess (3) located on an outer surface of the front panel (2) and at least one groove (4) located on an inner surface of the front panel (2).The capacitive keyboard reader (1) in turn also comprises at least one row of electrodes located on the inner surface of the front panel (2), each electrode group comprising at least one transmission electrode (Tx) and one receiving electrode (Rx) facing the recess (3); wherein the groove (4) is positioned and oriented around the electrode group and the corresponding recess (3), occupying a space between the recess (3) and the electrode group; wherein the electrode group, during operation, generates electric field lines between the transmission electrode (Tx) and the receiving electrode (Rx); and wherein the groove (4) is configured and positioned to concentrate the electric field flux lines (Fᴄᴇ) of the electrode group to an area at the bottom of the corresponding recess (3) to which it faces.