Frequency conversion in a touch sensor
First Claim
1. A touch sensitive device comprising:
- touch interface comprising rows and a column;
signal generator for generating a plurality of unique orthogonal signals on at least a plurality of the rows, respectively, the plurality of unique orthogonal signals being in a first range of frequencies and having a first frequency spacing;
heterodyning frequency mixer configured;
to receivea column signal present on the column, the column signal comprising signals within the first range of frequencies and having the first frequency spacing, andan oscillating signal, andto outputa heterodyned signal based upon the column signal and the oscillating signal, the heterodyned signal comprising signals within a second range of frequencies at the first frequency spacing;
touch processor configured to identify touch on the touch interface based at least in part on the heterodyned signal.
2 Assignments
0 Petitions
Accused Products
Abstract
A touch sensitive device includes a touch interface having rows and columns, a signal generator for generating a plurality of unique orthogonal signals in a first range and having a first frequency spacing on at least a plurality of the rows, respectively, and a heterodyning frequency converter. The heterodyning frequency converter receives a signal present on a column, the signal comprising signals within the first range and having the first frequency spacing. The heterodyning frequency converter converts the signal to a heterodyned signal comprising signals in a second range and having the first frequency spacing, and outputs the heterodyned signal. A touch processor identifies touch on the touch interface at least in part by processing the heterodyned signal.
-
Citations
20 Claims
-
1. A touch sensitive device comprising:
-
touch interface comprising rows and a column; signal generator for generating a plurality of unique orthogonal signals on at least a plurality of the rows, respectively, the plurality of unique orthogonal signals being in a first range of frequencies and having a first frequency spacing; heterodyning frequency mixer configured; to receive a column signal present on the column, the column signal comprising signals within the first range of frequencies and having the first frequency spacing, and an oscillating signal, and to output a heterodyned signal based upon the column signal and the oscillating signal, the heterodyned signal comprising signals within a second range of frequencies at the first frequency spacing; touch processor configured to identify touch on the touch interface based at least in part on the heterodyned signal. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19)
-
-
20. A touch sensitive device comprising:
-
touch interface comprising rows and columns; signal generator for generating a plurality of unique orthogonal signals on at least a plurality of the rows, respectively, the plurality of unique orthogonal signals being in a first range of frequencies and having a first frequency spacing; heterodyning frequency mixer configured; to receive a column signal present on each of the columns, the column signals comprising signals within the first range of frequencies and having the first frequency spacing, and an oscillating signal, and to output a heterodyned signal for each column, each heterodyned signal based upon one of the column signals and the oscillating signal, the heterodyned signals each comprising signals within a second range of frequencies at the first frequency spacing; touch processor configured to identify touch on the touch interface based at least in part on the heterodyned signals.
-
Specification