continued from part 2 - Controller General of Patents, Designs, and ...

(12) PATENT APPLICATION PUBLICATION (21) Application No.1830/KOL/2008 A
(19) INDIA
(22) Date of filing of Application :27/10/2008 (43) Publication Date : 05/06/2009
(54) Title of the invention : TWIN-CONTACT KEYBOARD ARRANGEMENT
(51) International classification
:H03M
11/00
(31) Priority Document No :11/940,881
(32) Priority Date :15/11/2007
(71)Name of Applicant :
1)POLYCOM, INC.
Address of Applicant :4750 WILLOW ROAD,
PLEASANTON, CALIFORNIA U.S.A.
(72)Name of Inventor :
1)OKUNAMI, ALVIN
(33) Name of priority country :U.S.A.
(86) International Application No
:NA
Filing Date
:NA
(87) International Publication No : NA
(61) Patent of Addition to Application Number :NA
Filing Date
:NA
(62) Divisional to Application Number
:NA
Filing Date
:NA
(57) Abstract :
Devices, methods, and techniques for keyboard scanning are disclosed herein. Keyboard arrangements can include a plurality of keys
and a keyboard decoder. Each of the plurality of keys can include at least one drive contact and a plurality of sense contacts. Each
drive contact can be connected to an output (drive) line of the keyboard decoder, and each sense contact can be connected to an input
(sense) line of the keyboard decoder such that each key is connected to a unique combination of sense lines. Key presses can be
identified by the unique combination of sense lines triggered. The combination of sense lines triggered can be used as an address to a
lookup table indicating the function of the various keys. Variations of drive signal properties, e.g., frequency, phase, and waveshape,
can be used to further distinguish key inputs and/or provide for a greater number of keys and/or corresponding functions.
No. of Pages : 14 No. of Claims : 18
The Patent Office Journal 05/06/2009 26349