Patent Application
20220269918
This application claims priority of Taiwanese Utility Model Patent Application No 110201862, filed on Feb. 19, 2021.
The disclosure relates to a smart card, and more particularly to a smart card for recognizing a fingerprint of a user.
Referring to
Since the fingerprint sensor 94 is not covered by anything, the fingerprint sensor 94 is prone to being stained with dust, which would reduce sensitivity of fingerprint detection and accuracy of fingerprint identification.
Therefore, an object of the disclosure to provide a smart card for recognizing a fingerprint of a user that can alleviate at least one of the drawbacks of the prior art.
According to the disclosure, the smart card includes a card body, a transmission unit, a fingerprint sensor, a processing unit and a cover layer.
The card body has a front surface and a back surface that are opposite to each other, and is formed with a cavity on the front surface.
The transmission unit is disposed on the card body, and is configured to be coupled to a card reading module, and to output electricity based on an electrical signal generated by the card reading module.
The fingerprint sensor is electrically connected to the transmission unit for receiving the electricity therefrom, has a sensing surface for detecting the fingerprint, is accommodated in the cavity of the card body with the sensing surface opposite to the back surface of the card body and receding with respect to the front surface, and is configured to be activated in response to receipt of the electricity from the transmission unit, and after being activated, to generate a detection signal based on the fingerprint upon detecting the fingerprint. The processing unit is disposed in the card body, is electrically connected to the transmission unit and the fingerprint sensor respectively for receiving the electricity and the detection signal therefrom, and is configured to be activated in response to receipt of the electricity from the transmission unit and after being activated, to perform signal processing on the detection signal upon receiving the detection signal.
The cover layer is disposed in the cavity of the card body and covers the sensing surface of the fingerprint sensor.
Other features and advantages of the disclosure will become apparent in the following detailed description of the embodiments with reference to the accompanying drawings, of which:
Before, the disclosure is described in greater detail, it should be noted that her considered appropriate, reference numerals or terminal portions of reference numerals have been repeated among the figures to indicate corresponding or analogous elements, which may optionally have similar characteristics.
Referring to
The card reading module 82 is adapted to be coupled to a computer or a cloud computing platform (e.g., a cloud server) for accessing a database running thereon. The card reading module 82 includes a contactless ca td reader 821 and a contact card reader 822. The contactless card reader 821 and the contact card reader 822 are accommodated in a housing (not shown) of the card reading module 82.
The smart card includes card body a transmission unit 2, a fingerprint sensor 3, a processing unit 4 and a cover layer 5. It should be noted that an actual overall thickness of the smart card is relatively thin, and for clarity of illustration, components of the smart card may be enlarged where appropriate: in
The card body 1 has an appearance of a rectangular sheet, and is made of plastic. The card body 1 has a front surface 11 and a back surface. 12 that are opposite to each other, and is formed with a cavity 13 in the front surface 11. In one embodiment, the card body 1 is made of other electrical insulator such as silicone rubber and polyimide, and has a specific appearance that is designed based on needs.
The transmission unit 2 is disposed on the card body 1. The transmission unit 2 is configured to be coupled to the card reading module 82, and to output electricity based on an electrical signal generated by the card reading module 82.
Specifically, the transmission unit 2 includes an induction coil 22 and a rectifier circuit 23. The induction ccii 22 is embedded in the card body 1. The induction coil 22 serves as an antenna for communicating with the contactless card reader 821, and is configured to be inductively coupled to the contact mess card reader 821 so as to induce generation of the electrical signal by the contactless card reader 821 to thereby produce an alternating current (AC) voltage through electromagnetic induction. The rectifier circuit 23 is electrically connected between the induction coil 22 and each of the fingerprint sensor 3 and the processing unit 4. The rectifier circuit 23 is configured to generate the electricity in direct current (DC) based on the AC voltage, produced by the induction coil 22, and to provide the electricity to the fingerprint sensor 3 and the processing unit 4.
The transmission unit 2 further includes a convertor circuit 21. The convertor circuit 21 is electrically connected to the fingerprint sensor 3 and the processing unit 4, and is disposed on and exposed from the front surface 11 of the card body 1. The convertor circuit 21 is configured to be physically and electrically connected to the contact card reader 822 for receiving the electrical signal from the contact card reader 822 and to convert the electrical signal into the electricity. In some embodiments, the converter circuit 21 may be implemented to have a contact pad (see
In one, embodiment, the induction coil 22 and the rectifier circuit 23 of the transmission unit 2 are omitted, so the transmission unit 2, which includes the converter circuit 21, is only allowed to be connected to the contact card reader 822.
In one embodiment, the convertor circuit 21 of the transmission unit 2 is omitted, so the transmission unit 2, which includes the induct coil 22 and, the rectifier circuit 23, is only allowed to be used with the contactless card reader 821.
The fingerprint sensor electrically connected to the transmission unit 2 for receiving the electricity therefrom, and configured to operate based on the electricity. The fingerprint sensor 3 has a sensing surface 31 for detecting the fingerprint 81, and is accommodated in the cavity 13 of the card body 1 with the sensing surface 31 opposite to and faces away from the back surface 12 of the card body 1 and receding with respect to the front surface 11. The fingerprint sensor 3 is configured to be activated in response to receipt of the electricity from the transmission unit and after being activated, to generate a detection signal based on the fingerprint 81 upon detect in the fingerprint 81.
The fingerprint sensor 3 includes a contact pad and a controller (not shown), and the whole of the fingerprint sensor 3 is implemented by an unpackaged chip. The controller of the fingerprint sensor 3 includes substrate that may be implemented by a silicon substrate, a g as substrate, a polyimide (PI) film, an Ajinomoto build-up film (ABF), bismaleimide triazine resin film, or the like.
The processing unit 4 is disposed in the card body 1 under the transmission unit 2, and is closer to the back surface 12 of the card body 1 than the transmission unit 2. The processing unit 4 is electrically connected to the transmission unit 2 (specifically, the convertor circuit 21 and the rectifier circuit 23) and the fingerprint sensor 3 respectively for receiving the electricity and the detection signal therefrom. The processing unit 4 is configured to be activated in response to receipt of the electricity from the transmission unit 2, and after being activated, to perform signal processing on the detection signal upon receiving the detection signal.
In one embodiment, the processing unit 4 is configured to store in advance reference data that indicates a reference fingerprint f a holder of the smart card, and to perform fingerprint comparison based on a detected fingerprint indicated by the detection signal (i.e., the fingerprint 81) and the reference fingerprint indicated by the reference data.
The processing unit 4 is further configured to generate, when it is determined that the detected fingerprint matches the reference fingerprint in the fingerprint comparison, an affirmative notification indicating that the user to which the fingerprint 81 belongs is identified as the holder of the smart card, and to generate, when it is determined that the detected fingerprint does not match the reference fingerprint in the fingerprint comparison, a negative notification indicating that the user to which the fingerprint 81 belongs is not the holder of the smart card. It should be noted that implementation of fingerprint comparison is not limited to what is disclosed herein and may vary in other embodiments. The fingerprint comparison, performed by the processing unit 4 is well known in the art, and details thereof are omitted herein for the sake of brevity.
In one embodiment, the reference data that indicates a reference fingerprint of a holder of the smart card is stored in a database running on a computer or a cloud computing platform that is coupled to the card reading module 82.
The processing unit 4 may be implemented by processor, a central processing unit (CPU), microprocessor, a micro control unit (MCU), a system on a chip (SoC), or any circuit configurable/programmable in a software manner and/or hardware, manner to implement functionalities discussed in this disclosure.
The cover layer 5 is in a form of a film. The cover layer 5 is disposed in the cavity 13 of the card body 1 and is coated over the sensing surface 31 of the fingerprint sensor 3. The cover layer 5 has an upper surface 51 that is coplanar with the front surface 11 of the card body 1, and a bottom surface 52 that is opposite to the upper surface 51 and that contacts the sensing surface 31 of the fingerprint sensor 3.
The cover layer 5 is made of a solid solution, or a high-k dielectric material such as a high-k colloidal polymer that can be hardened or toughened by employing a curing chemical process. In one embodiment, the cover layer 5 is fabricated by pasting a specific adhesive sheet on the sensing surface 31 of the fingerprint sensor 3. In one embodiment, the cover layer 5 is fabricated by filling a predetermined liquid (e.g., emulsion or liquid crystal) on the sensing surface 31 of the fingerprint sensor 3 and then solidifying the predetermined liquid. A thickness (D) of the cover layer 5 between the upper surface 51 and the bottom surface 52 ranges from 25 micrometers to 80 micrometers. The cover layer 5 has a dielectric constant ranging from one to eight.
Covered by the cover layer 5, the fingerprint sensor 3 may be prevented from being stained with dust. Therefore, the fingerprint sensor 3 is capable of accurately detecting charges on most portions of the fingerprint 81, and accordingly sensitivity of fingerprint detection and accuracy of fingerprint identification of the smart card may be maintained.
Referring to
The smart card further includes a protective layer 6. The protective layer 6 is implemented by a transparent film, and may be made of a high-k dielectric material such as a high-k polymer (e.g., polyimide), aluminium oxide (Al2Oj) or silicon dioxide (SiO2). The protective layer 6 is coated over the front surface 11 of the card body 1 and the cover layer 5. The convertor circuit. 21 of the transmission unit 2 is exposed from and coplanar with the protective layer 6.
It should be noted that the protective layer 6 covers the upper surface 51 of the cover layer 5 such that the cover layer 5 is sealed between the protective layer 6 and the card body 1. Because no air gap exists between the protective layer 6 and the cover layer 5 or between the cover layer 5 and the fingerprint sensor 3, the ability of the fingerprint sensor 3 to detect charges on the fingerprint 81 is kept equal and uniform for various parts of the fingerprint 81 when the user places his/her finger on the protective layer 6. Therefore, sensitivity of fingerprint detection and accuracy of fingerprint identification of the smart card may be enhanced. It is worth to note that the protective layer 6 does not have to be opened for exposing the fingerprint sensor 3, so fabricating the protective layer 6 may be, simple.
To sum up, the smart card according to the disclosure utilizes the cover layer 5 to cover the fingerprint sensor 3 so as to prevent the fingerprint sensor 3 from being stained with dust, Therefore, sensitivity of fingerprint detection and accuracy of fingerprint identification of the smart card may be unaffected by dust accumulation. Moreover, when the fingerprint sensor 3 is further covered by the protective layer 6 on the upper surface 51 of the cover layer 5, the thickness (D) of the cover layer 5 and the dielectric constant of the cover layer 5 may be designed to maintain the sensitivity of fingerprint detection and the accuracy of fingerprint identification of the smart card.
In the description above, for the purposes of explanation, numerous specific details have been set forth in order to provide a thorough understanding of the embodiments. It will be apparent, however, to one skilled in the at, that one or more other embodiments may be practiced without some of these specific details. It should also be appreciated that reference throughout this specification to “one embodiment,” “an embodiment,” an embodiment with an indication of an, ordinal number and so forth means that particular feature, structure, or characteristic may be included in the practice of the disclosure. It should be further appreciated that in the description, various features are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of various inventive aspects, and that one or more features or specific details from one embodiment may be practiced together with one or more features or specific details from another embodiment, where appropriate, in the practice of the disclosure.
While the disclosure: has been described in connection with what are considered the exemplary embodiments, it is understood that this disclosure is not limited to the disclosed embodiments but is intended to cover various arrangements included within the spirit and scope of the broadest interpretation so as to encompass all such modifications and equivalent arrangements.
| Number | Date | Country | Kind |
|---|---|---|---|
| 110201862 | Feb 2021 | TW | national |
