TOUCH SENSING APPARATUS AND METHOD OF OPERATING THE SAME

摘要

A touch sensing apparatus includes a group of emitters arranged to emit light to illuminate at least part of the touch surface, a light detector arranged to receive light from the group of emitters, and a processing element. Each emitter is controlled to transmit a code by way of the emitted light such that the code identifies the respective emitter. The codes may at least partly be transmitted concurrently. The codes may be selected such that a value of an autocorrelation of each code is significantly higher than a value of a cross-correlation between any two codes of different emitters. The processing element processes an output signal from the light detector to separate the light received from the individual emitters based on the transmitted codes, and to determine the position of the object/objects based on the light received from the individual emitters.

主权项

1. A touch sensing apparatus, comprising:
a touch surface; a group of emitters arranged to emit light to illuminate at least part of the touch surface; a group of light detectors arranged to receive light from the group of emitters, the group of light detectors configured to generate an output signal; and a processing element configured to process the output signal from the group of light detectors to determine the position of one or more objects interacting with the touch surface; wherein each emitter is controlled to transmit a code by way of the emitted light such that the code identifies the respective emitter, and wherein the processing element is configured to separate the light signal received from individual emitters from the output signal based on the transmitted codes.