Patent ID: 7230609

Claim:
A touch position coordinate detecting system, comprising: a transmitting transducer operable for launching an initial burst of acoustic waves on a panel, wherein the initial burst includes at least a first and a second frequency component; at least one array of reflective patterns, each pattern being arranged on the panel for reflecting an amplitude portion of the initial burst of acoustic waves, the array extending substantially along a predetermined axis, wherein the array includes at least a first and second interspersed sub-array, the first and second sub-arrays being adapted for reflecting at least a portion of the first and second frequency components, respectively; a receiving transducer operable for successively receiving the reflected portions of the initial burst of acoustic waves from the array of reflective patterns, wherein the received reflected portions include a delay due to the travel of the acoustic waves between the successive patterns, thereby delivering a time output signal; an output signal processing unit operable for detecting a time localized damping in the amplitude of the reflected first and second frequency components caused by a touch on the panel that produces an acoustic attenuation of at least one reflected portion, wherein the acoustic attenuation is useful for determining at least one coordinate position of the touch along the predetermined axis.