Card reader
To ensure reliable detection of a skimming device over an extensive area inside the card reader, it is currently necessary to install a large number of sensors, which may lead to increased manufacturing cost. A card reader for reading magnetic information while feeding, through a feed path, a card inserted into the card reader, includes: an oscillator configured to emit an ultrasonic wave to the feed path; and a receiver configured to receive the ultrasonic wave emitted from the oscillator. The card reader is configured to detect an object present in the feed path by comparing a first received waveform and a second received waveform with each other, the first received waveform being a waveform received at the receiver, the second received waveform being a previously acquired waveform under normal condition received at the receiver.
1 . A card reader for reading magnetic information while feeding, through a feed path, a card inserted into the card reader, the card reader comprising:
a first end including an opening;
a second end opposite the first end;
a feed path connecting the first end to the second end and configured to guide the card through the card reader;
an oscillator configured to emit an ultrasonic wave to the feed path and located along the feed path at either the first end or the second end; and
a receiver configured to receive the ultrasonic wave emitted from the oscillator and located along the feed path at either the first end or the second end and opposite the end where the oscillator is located,
wherein the card reader is configured to detect an object present in the feed path by comparing a first received waveform and a second received waveform with each other, the first received waveform being a waveform received at the receiver, the second received waveform being a previously acquired waveform under normal condition received at the receiver.
2 . The card reader according to claim 1 ,
wherein the card reader is configured to, in response to a difference in waveform height and waveform length between the first received waveform and the second received waveform exceeding a predetermined value, determine that the object is present.
3 . The card reader according to claim 1 ,
wherein the card reader is configured to, based on a previously constructed machine-learning model, determine that the object is present from the first received waveform.
4 . The card reader according to claim 1 ,
wherein the oscillator and the receiver are each disposed on a line of passage of a magnetic stripe of the card in the feed path.
5 . The card reader according to claim 2 ,
wherein the oscillator and the receiver are disposed in opposite end portions of the feed path in a transverse direction of the card.
6 . The card reader according to claim 4 , wherein the card reader is configured to execute:
a first detection process of, before the card is inserted, acquiring the first received waveform, and detecting an object present in the feed path, and
a second detection process of, in response to a determination as a result of the first detection process that no object is present, after the card is inserted and ejected, acquiring a third received waveform at the receiver, and detecting an object remaining after card ejection by comparing the first received waveform and the third received waveform with each other.
7 . The card reader according to claim 1 , wherein
the feed path is defined by an upper feed guide and a lower feed guide, that both extend from the first end to the second end, and
the lower feed guide has a surface provided with irregularities from the first end to the second end.
8 . The card reader according to claim 1 , wherein
the feed path is defined by an upper feed guide and a lower feed guide, that both extend from the first end to the second end, and
the lower feed guide has a surface provided with an ultrasonic absorber.
9 . The card reader according to claim 1 ,
wherein the receiver comprises a plurality of receivers disposed at different locations of the feed path.
10 . The card reader according to claim 1 ,
wherein the oscillator and the receiver comprise a single ultrasonic sensor capable of both ultrasonic wave emission and reception.
11 . The card reader according to claim 1 , wherein
the feed path is defined by an upper feed guide and a lower feed guide, that both extend from the first end to the second end.
12 . The card reader according to claim 11 , wherein
the oscillator and the receiver are both located on the upper feed guide.
13 . The card reader according to claim 11 , wherein
the oscillator and the receiver are both located on the lower feed guide.