Patent ID: 9542787
Date: 2017-01-10
CPC Classifications: G01H,G07D

Claim:
1. A method for detecting a feature of a financial document using acoustics, the method comprising: providing a first acoustic transmitter and a first acoustic receiver; providing a second acoustic transmitter and second acoustic receiver; disposing the financial document between the first acoustic transmitter and the first acoustic receiver and between the second acoustic transmitter and the second acoustic receiver; emitting a first acoustic signal from the first acoustic transmitter to the first acoustic receiver while the financial document is between the first acoustic transmitter and the first acoustic receiver; emitting a second acoustic signal from the second acoustic transmitter to the second acoustic receiver while the financial document is between the second acoustic transmitter and the second acoustic receiver; modulating the first acoustic signal so that the first acoustic signal differs from the second acoustic signal; receiving the first acoustic signal and the second acoustic signal at the first acoustic receiver; processing acoustic signals received by the first acoustic receiver to extract the first acoustic signal and the second acoustic signal; and determining the presence of a feature between the first acoustic transmitter and the first acoustic receiver of the financial document using at least the first acoustic signal and determining the presence of a feature between the second acoustic transmitter and the first acoustic receiver of the financial document using at least the second acoustic signal.