Magnetic counterfeit detectors are becoming a popular form of currency detection. These machines rely on small magnetic sensors to scan and confirm the legitimacy of a bill that is passed through the machine.
There is an iron oxide used in the black ink of currency which provides the machine with a way of separating counterfeit from legitimate currency.
Magnetic counterfeit money detectors have played an important role in stopping counterfeit currency since in today’s world counterfeiting has moved from the hands of skilled engravers to high school students who are good with computers.
The small magnetic fields in paper currency produce specific signatures that can be read by the magnetic sensors to help the machine determine the denomination of the currency that is being passed through the machine.
Depending on the circuit management noise and magnetic biasing of the machine they can be more or less accurate in finding counterfeit currency.
Some magnetic machines use a recording head that is pressed against the surface of the bill. However, machines that have non-contact sensors can prevent the bill from becoming jammed in the machine.
It has been found that the greater the distance between the bill and the sensor then there is a higher minimum required for detecting a counterfeit bill that is passing through the machine.
The increasing evolution of magnetic sensing equipment is necessary as computers become more sophisticated and make it easier for individuals to counterfeit currency.
Many new forms of counterfeit bills are becoming impossible to detect with optically based scanning equipment. Therefore, many companies are changing to the more reliable and dependent form of magnetic scanning.
In addition, the higher density and sensitivity of magnetic scanning devices will eventually help to design new scanning devices that can be placed in a variety of instruments to help make the detection of counterfeit currency even easier than it is today.