Ink screen mobile phone shell with annular NFC antenna

Abstract

The utility model belongs to the technical field of ink screen mobile phone shells, and relates to an ink screen mobile phone shell with an annular NFC antenna, which comprises a mobile phone shell body, and the upper part of the mobile phone shell body is provided with an opening or a groove for avoiding a camera module; the NFC receiving antenna is arranged along the periphery of the open hole in a surrounding manner to form a closed loop; the NFC receiving antenna is electrically connected with the circuit board through the flexible connecting part; the circuit board is electrically connected with the display module; and the display module is used for displaying an image based on the energy and the data received by the NFC receiving antenna. The NFC receiving antenna is arranged along the periphery of the opening of the camera module in a surrounding manner, so that the NFC receiving antenna is not limited by the projection of the camera, and the NFC interference to the mobile phone is reduced.

Description

Technical Field

[0001] This utility model belongs to the technical field of e-ink screen phone cases, and relates to an e-ink screen phone case with a ring NFC antenna. Background Technology

[0002] Existing passive e-ink screen phone cases typically use a sheet-like NFC receiving antenna mounted on the back of the phone case. This antenna needs to overlap as much as possible with the phone's built-in NFC antenna in the projection direction to achieve sufficient magnetic coupling, thereby enabling energy harvesting and data transmission. In this type of solution, the e-ink screen display module uses the energy harvested by the NFC receiving antenna to drive the refresh display.

[0003] However, this traditional design has the following shortcomings:

[0004] 1. Interference with the phone's NFC function: Since the NFC receiving antenna of the phone case is directly covered by the phone's built-in NFC antenna, it is very easy to cause signal shielding or coupling interference, thereby affecting the phone's own NFC function, such as mobile payment, access control card swiping, etc.

[0005] 2. Camera Module Protrusion Limits Layout: With the increasing number of cameras in smartphones and the widespread adoption of protruding module designs, there is usually a large camera island area at the top of the back of the phone. In traditional solutions, if the NFC receiving antenna is deployed entirely above the back panel, it would require openings for the camera module, inevitably resulting in the antenna being segmented or occupying insufficient space, reduced coupling efficiency, and even inability to guarantee the stability of NFC power acquisition.

[0006] 3. Poor structural compatibility: The traditional arrangement of sheet antennas is highly sensitive to the shape of mobile phone models and camera modules, which is not conducive to the adaptation and universal design of different models.

[0007] Therefore, while ensuring the power supply and display updates of the e-ink screen, the existing technology struggles to guarantee the normal use of the phone's NFC function and the structural design for compatibility with the camera module, and urgently needs improvement. Utility Model Content

[0008] The purpose of this utility model is to address the shortcomings of existing technologies by providing an e-ink screen phone case with a ring NFC antenna. By arranging the NFC receiving antenna around the periphery of the camera module opening, it is not limited by the camera protrusion and reduces NFC interference to the phone.

[0009] To achieve the above objectives, the present invention adopts the following technical solution:

[0010] An e-ink screen phone case with a ring-shaped NFC antenna, comprising:

[0011] The phone case body has an opening or groove on the upper part to avoid the camera module;

[0012] An NFC receiving antenna is arranged around the periphery of the opening to form a closed loop;

[0013] The NFC receiving antenna is electrically connected to the circuit board via the flexible connection part.

[0014] A circuit board, which is electrically connected to the display module;

[0015] The display module is used to display images based on the energy received by the NFC receiving antenna.

[0016] Furthermore, the projection area of ​​the NFC receiving antenna covers or surrounds the projection area of ​​the mobile phone's built-in NFC antenna, so that the NFC receiving antenna is magnetically coupled to the mobile phone's built-in NFC antenna.

[0017] Furthermore, the closed loop of the NFC receiving antenna is a rectangle, a rounded rectangle, a circle, or an irregular structure that matches the outer edge of the opening.

[0018] Furthermore, the flexible connection portion is a flexible circuit board, which extends into the inner wall of the phone case and is used to connect to the circuit board.

[0019] Furthermore, a matching circuit is provided on the device to perform impedance matching on the NFC receiving antenna, so as to reduce interference with the NFC function of the mobile phone while satisfying the display module driving requirements.

[0020] Furthermore, the display module is an electronic ink screen.

[0021] By applying the technical solution of this utility model, the NFC receiving antenna is arranged around the periphery of the camera opening, leaving the central area empty. This eliminates the limitations imposed by the camera protrusion, effectively improving the space utilization and aesthetic integrity of the phone case design. By covering or surrounding the phone's built-in NFC antenna on the projection, a closed loop can capture the magnetic flux of the phone's NFC antenna. Even with a central opening, effective induction can still be achieved, enabling energy harvesting and data transmission. The design of the surrounding structure and its relationship with the projection ensures that the antenna is no longer directly and completely overlapped with the phone's NFC, reducing the possibility of obstruction and over-coupling, thereby improving the reliability of the phone's own NFC function.

[0022] Other features and advantages of the present invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the present invention may be realized and obtained by means of the structures particularly pointed out in the written description and the accompanying drawings. Attached Figure Description

[0023] The present invention will now be described in detail with reference to the accompanying drawings, so that the above-mentioned advantages of the present invention will become clearer.

[0024] Figure 1 This is an exploded structural diagram of an e-ink screen phone case with a ring NFC antenna according to this utility model.

[0025] Figure 2 This is a partially exploded schematic diagram of an e-ink screen phone case with a ring NFC antenna according to this utility model.

[0026] Figure 3 This is a schematic diagram illustrating the use of an e-ink screen phone case with a ring-shaped NFC antenna according to this utility model.

[0027] Figure 4 This is a structural schematic diagram of an e-ink screen phone case with a ring-shaped NFC antenna according to this utility model. Detailed Implementation

[0028] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this utility model, and should not be construed as limiting this utility model.

[0029] In the description of this utility model, it should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0030] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0031] In the embodiments of this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in this utility model can be understood according to the specific circumstances.

[0032] Reference Appendix Figure 1-4 As shown, an e-ink screen phone case with a ring-shaped NFC antenna includes a phone case body 100. The upper part of the phone case body 100 is provided with an opening 110 or a groove 110 for avoiding the camera module. Unlike the prior art where a sheet antenna covers the back panel of the phone, this embodiment arranges the NFC receiving antenna 200 around the periphery of the opening 110 or groove 110 to form a closed loop, thereby ensuring that the antenna forms a continuous sensing circuit without affecting the installation and use of the camera module.

[0033] The NFC receiving antenna 200 is electrically connected to the circuit board via a flexible connector 300. Preferably, the flexible connector 300 is a flexible circuit board that can extend along the inner wall of the phone case to the circuit board. Because the flexible circuit board has good bending performance, it can maintain a stable electrical connection during assembly and use, avoiding breakage or poor contact due to mechanical stress.

[0034] The circuit board is electrically connected to the display module 400, which is preferably an e-ink screen. When the built-in NFC antenna of the mobile phone generates an alternating magnetic field at its operating frequency, this magnetic field passes through the closed-loop NFC receiving antenna 200, thereby inducing a voltage on the antenna. After processing by the circuit board, this voltage provides energy and data signals to the e-ink screen, enabling it to refresh the displayed content. After the refresh is complete, the e-ink screen can maintain its display even without a power input, making it particularly suitable for passive power supply applications.

[0035] To further demonstrate the feasibility of the proposed ring NFC receiving antenna 200, the electromagnetic induction mechanism is explained below. According to the integral form of Maxwell-Faraday's law, we have... Where S is an arbitrary open curved surface enclosed by the receiving coil, and B is the magnetic induction intensity generated in space by the transmitting end of the mobile phone's built-in NFC antenna. From this relationship, it can be seen that the first-order factor determining the magnitude of the induced electromotive force across the receiving coil is the change in magnetic flux through the area enclosed by the closed loop over time, rather than the filling ratio of the conductor within that area. Therefore, as long as the receiving coil forms a continuous closed loop, and its projection at least partially covers or surrounds the projection area of ​​the transmitting antenna, such that a considerable portion of the near-field magnetic flux generated by the mobile phone's NFC antenna passes through the closed loop, the receiving end can obtain an induced voltage and coupling energy of the same type and magnitude as the traditional sheet-like overlapping scheme.

[0036] In a near-field magnetic coupling system, the receiver is equivalent to a resonant branch consisting of inductor L2, series resistor R2, and matching capacitor C; the transmitter current I1 establishes an approximately circular alternating magnetic field in space at angular frequency ω, and the open-circuit induced voltage at the receiver can be expressed as... Where M is the mutual inductance of the two coils, satisfying k is the coupling coefficient, 0 < k < 1. For a given transmitter and distance conditions, k is mainly affected by the geometric enclosure relationship, the closed loop area, attitude, and distance, and is not sensitive to whether the center is hollowed out; in other words, the closed loop surrounding the camera opening 110 can achieve a mutual inductance M close to that of the traditional overlapping scheme when maintaining a sufficient enclosure area and a suitable projection relationship. To compensate for the possible increase in R2 due to the lengthening of the loop path, this invention preferably increases the conductor linewidth / copper thickness, reasonably controls the number of turns and distributed capacitance, and uses a matching network to pull the equivalent operating point back to the 13.56MHz resonance, thereby maintaining the receiver quality factor Q within the target range and maximizing the effective incident power.

[0037] The key difference between the annular arrangement described in this invention and the traditional sheet-like overlapping scheme is that the receiving coil is no longer located in a solid covering position directly above the transmitting coil, but rather forms a closed loop around the periphery of the camera opening 110, surrounding the strong field region of the transmitting coil. Since the e-ink screen refresh only requires energy momentarily and display maintenance does not require continuous power, as long as the magnetic flux captured by the closed loop can be converted into energy and data signals that meet the driving threshold within the specified contact distance, the system function can be realized. In practice, designing the closed loop shape as a rectangle, rounded rectangle, circle, or irregular shape that matches the outer edge of the camera island, and ensuring that its projection at least partially covers or surrounds the projection area of ​​the phone's built-in NFC antenna, can maintain stable coupling while avoiding the camera; further, using thin magnetic sheets segmented along the periphery to guide the magnetic flux and suppress eddy current losses in metal components can further improve mutual inductance and consistency.

[0038] Furthermore, since the NFC receiving antenna 200 is arranged around the periphery of the camera opening 110, the phone case body 100 forms a complete opening in the corresponding area of ​​the camera module, allowing the appearance of the camera module to be fully exposed. This opening structure not only avoids spatial conflict between the NFC receiving antenna 200 and the camera module, but also preserves the original design and recognizability of the phone camera module. For example, some phone models have strong decorative and brand characteristics in the shape, arrangement, and material of the camera module. The opening design in this embodiment can intuitively display these appearance elements, thereby improving the overall aesthetics and visual coordination of the phone case body 100 while ensuring the normal display function of the display module 400. Furthermore, this opening style avoids the obstruction of the camera area by the traditional back panel antenna, so that the phone case body 100 does not appear bulky and monotonous when in use, but can form a unified and simple visual effect with the phone body, better highlighting the design of the camera module, making the product more exquisite and beautiful in appearance, and improving the user experience and satisfaction.

[0039] Furthermore, the projection area of ​​the NFC receiving antenna 200 at least partially covers or surrounds the projection area of ​​the phone's built-in NFC antenna. This arrangement ensures that even if the center of the loop is hollowed out due to the opening 110, the magnetic flux emitted by the phone's built-in NFC antenna still passes through the receiving antenna, thereby achieving effective energy harvesting and data transmission.

[0040] Furthermore, the closed loop of the NFC receiving antenna 200 can be designed as a rectangle, rounded rectangle, circle, or an irregular shape that fits the outer edge of the opening 110, depending on the shape of the camera module of different models. Regardless of the shape of the loop, as long as it remains closed and surrounds the opening 110, a stable magnetic flux path can be formed to achieve the required sensing effect. This flexible structural design can adapt to a variety of different camera module layouts, improving the product's versatility.

[0041] Furthermore, the circuit board is equipped with a matching circuit for impedance matching of the NFC receiving antenna 200. Through a reasonable matching design, the interference to the phone's own NFC function can be reduced while meeting the e-ink screen refresh requirements, and energy transfer efficiency can be improved. This matching circuit ensures stable operation of the system under different models and antenna configurations. The matching circuit is a commonly used circuit component in existing NFC e-ink screen phone cases. This application mainly addresses the conflict between the antenna shape and position and the camera island; therefore, the circuit details are not specifically shown here. For details, please refer to the prior art: Passive Driving Circuit for E-ink Screens and Phone Cases—CN222600502U.

[0042] As can be seen from the above embodiments, this utility model achieves stable energy acquisition and data display under passive conditions by arranging a ring-shaped NFC receiving antenna 200 around the camera opening 110, and combining the connection method of the flexible circuit board, the segmented magnetic sheet arrangement and the impedance matching design. This not only avoids the impact of traditional sheet antennas on the NFC function of cameras and mobile phones, but also improves the compatibility of different models and the overall reliability of use.

[0043] Finally, it should be noted that the above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A ring-shaped NFC antenna e-ink screen phone case, characterized in that, include: The phone case body (100) has an opening (110) or groove on the upper part for avoiding the camera module; An NFC receiving antenna (200) is arranged around the periphery of the opening (110) to form a closed loop; A flexible connection part (300) is provided, through which the NFC receiving antenna (200) is electrically connected to the circuit board; A circuit board, which is electrically connected to the display module (400); Display module (400) is used to display images based on the energy received by the NFC receiving antenna (200).

2. The e-ink screen phone case with a ring NFC antenna according to claim 1, characterized in that, The projection area of ​​the NFC receiving antenna (200) at least partially covers or surrounds the projection area of ​​the mobile phone's built-in NFC antenna, so that the NFC receiving antenna (200) is magnetically coupled to the mobile phone's built-in NFC antenna.

3. The e-ink screen phone case with a ring NFC antenna according to claim 1, characterized in that, The closed loop of the NFC receiving antenna (200) is a rectangle, a rounded rectangle, a circle, or an irregular structure that matches the outer edge of the opening (110).

4. The e-ink screen phone case with a ring NFC antenna according to claim 1, characterized in that, The flexible connecting part (300) is a flexible circuit board that extends into the inner wall of the phone case and is used to connect to the circuit board.

5. The e-ink screen phone case with a ring NFC antenna according to claim 1, characterized in that, The circuit board is equipped with a matching circuit for impedance matching of the NFC receiving antenna (200) to reduce interference with the NFC function of the mobile phone while satisfying the driving of the display module (400).

6. The e-ink screen phone case with a ring NFC antenna according to claim 1, characterized in that, The display module (400) is an electronic ink screen.

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