ANTENNA ARRANGEMENT FOR AN ELECTRONIC DEVICE AND AN ELECTRONIC DEVICE INCLUDING SAME

A wristworn device including a radio communication device for at least one of receiving signals from and transmitting signals to a communication device external to the wristworn device, the wristworn device including a non-electrically conductive watchcase that itself has an outer surface, a crystal that seals a first end of the watchcase and a case back that seals a second end of the watchcasing; an antenna structure comprising an outer conductive layer and an internal conductive layer electrically coupled to the outer conductive layer; a controller disposed in the casing of the watchcase and operatively coupled to the radio communication device, and wherein the outer conductive layer is electrically coupled to the radio communication device, and the outer conductive layer together with the inner conductive layer function as the antenna for at least one of reception or transmission of signals for the radio communication device. In the disclosed embodiments, the outer conductive layer is preferably disposed on the outer surface of the non-electrically conductive watchcase or embedded within the watchcase.

BACKGROUND OF THE INVENTION

The present invention relates generally to antennas, and in particular, to an improved antenna for a wristworn device having signal transmitting and/or receiving capabilities. In exemplary embodiments, the wristworn device is a timepiece such as a wristwatch, but, as will become quite clear below, a timepiece or wristwatch is only by way of example and not limitation. In particular, the invention is primarily directed to improved signal transmission and reception utilizing a non-electrically conductive watchcasing that has been provided with an antenna structure comprising a conductive layer embedded therein or provided thereon.

The prior art is full of examples of antennas associated with wristworn devices, such as wristwatches. For example, U.S. Pat. Nos. 5,072,231; 6,104,354; 6,028,555 and 6,154,177 are but just a few examples of devices incorporating loop antennas for signal reception and transmission. Although the use of loop antennas for signal reception and transmission has been found to be particularly desirable in timepieces, the use thereof in a timepiece comprised of a metal case has been found to have drawbacks and to be less than optimal, typically because of the poor performance due to the shielding of the antenna by the metal case itself. Additionally, electro-static discharge (ESD) is also a known problem when using a metal casing.

The present inventor already on at least one occasion has overcome the aforementioned deficiencies by way of the invention disclosed in U.S. Pat. No. 7,215,600, in which desirable signal reception and transmission thereof has been achieved with the use of a metal casing functioning as the antenna. The subject matter of U.S. Pat. No. 7,215,600 is incorporated by reference herein in its entirety.

However and notwithstanding the improved results provided by the embodiments set forth in the aforementioned '600 patent, further improvements are desirable. For example, it would be desirable to achieve at least all of the objectives and advantages set forth in U.S. Pat. No. 7,215,600 while using a non-electrically conductive watchcase.

OBJECTIVES AND SUMMARY OF THE INVENTION

Therefore, it is generally an object and advantage of the present invention to provide an improved antenna structure for a device comprising a non-electrically conductive watchcasing.

It is still a further object and advantage of the present invention to provide an improved antenna structure for a wristworn device having improved signal transmission and reception functionality.

It is another object and advantage of the present invention to provide an improved antenna structure for a wristworn timepiece that incorporates therein a receiver, transmitter and/or transceiver.

It is yet another object of the present invention is to provide an improved antenna structure for a wristworn device that reduces the number of components of the device yet provides satisfactory or even improved signal reception and/or transmission.

Yet another object and advantage of the present invention is to provide an improved antenna structure that reduces ESD.

Still another object and advantage of the present invention is to achieve all of the advantages and objectives as set forth in U.S. Pat. No. 7,215,600 while using a non-electrically conductive watchcase.

For example, it is an objective and advantage of the present invention to provide a wristworn device, including but not limited to a timepiece, that includes an improved antenna structure as disclosed herein.

Further objects and advantages of this invention will become more apparent from a consideration of the drawings and ensuing description.

The invention accordingly comprises the features of construction, combination of elements, arrangement of parts and methodology of construction that will be exemplified in the disclosure hereinafter set forth, and the scope of the invention will be indicated in the claims.

To overcome the perceived deficiencies in the prior art and to achieve the objects and advantages above and below, the present invention, generally speaking, in a first embodiment is directed to a wristworn device comprising a radio communication device for at least one of receiving signals from and transmitting signals to a communication device external to the wristworn device, the wristworn device comprising a non-electrically conductive watchcase that itself has an outer surface, a crystal that seals a first end of the watchcase and a case back that seals a second end of the watchcasing; an antenna structure comprising a conductive layer disposed on the outer surface of the non-electrically conductive watchcase and an internal conductive layer electrically coupled to the outer conductive layer; a controller disposed in the casing of the watchcase and operatively coupled to the radio communication device, and wherein the outer conductive layer is electrically coupled to the radio communication device, and the outer conductive layer together with the inner conductive layer function as the antenna for at least one of reception or transmission of signals for the radio communication device.

In another preferred embodiment, the invention is directed to a wristworn device comprising a radio communication device for at least one of receiving signals from and transmitting signals to a communication device external to the wristworn device, the wristworn device comprising a non-electrically conductive watchcase, a crystal that seals a first end of the watchcase and a case back that seals a second end of the watchcasing; an antenna structure comprising an outer conductive layer embedded within the watchcase and an internal conductive layer electrically coupled to the outer conductive layer; a controller disposed in the casing and operatively coupled to the radio communication device, and wherein the outer conductive layer is electrically coupled to the radio communication device, and the outer conductive layer together with the inner conductive layer together function as the antenna for at least one of reception or transmission of signals for the radio communication device.

In a specific preferred embodiment, the device is a wristworn device and in a more specific preferred embodiment the wristworn device is a timepiece.

Like reference numbers are used for like parts, although not every feature is numbered in each figure.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Reference shall be first made generally to the Figures and the following disclosure, which depicts and discloses a wristworn device, generally indicated at10, constructed in accordance with preferred embodiments of the present invention.

In a preferred embodiment, device10is a wristworn device, and preferably a timepiece. However, as indicated above, device10need not be limited to a timepiece or wristwatch, and may be a variety of other devices, such as a heart rate monitor, glucose monitor or other communication device, examples of which are disclosed in Published Application Serial No. 2004/0233788 (the '788 Published Application), which is hereby incorporated by reference in its entirety.

As illustrated inFIGS. 1 and 2, device10preferably comprises a non-electrically conductive watchcase15, a glass or plastic transparent watch crystal20that allows viewing of a watch dial22, a case back25and a watch movement, generally also referred to as controller30, which contains the electrical and mechanical mechanisms for timekeeping, including hand movement. For example, a plastic watchcase surely meets the definition of non-electrically conductive watchcase. A battery (not shown) is also provided. Watch dial22provides for the display of information in an analog or digital fashion (e.g. seeFIG. 3). As will be true for all the figures, it should be apparent that dial22is “under” the crystal20and that controller30(i.e. the movement) is preferably “under” the dial22.

As disclosed in the aforementioned U.S. Pat. No. 7,215,600, reference(s) cited therein and inFIG. 3herein, an “analog fashion” of display typically comprises the use of hands, while a “digital fashion” display (e.g. generically indicated at 90) typically consists of an LED, LCD, a dot matrix or a variety of the new display technologies that display information without the use of actual/physical indicator hands.

As is also well-known in the art, controller/movement30for device10(e.g. a watch movement”) preferably comprises a printed circuit board32that may contain thereon a microcontroller100(similar to controller100in the aforementioned '788 published application), and/or discrete semiconductor devices and/or an application specific integrated circuit (ASIC) to perform timekeeping and communications functions. Controller/movement30may also comprise one or more (e.g. stepping) motors (see generically indicated at M1-MninFIG. 3) for the rotation of the indicator (e.g. hour/minute, display) hands. Similarly, the controller or “movement”30may comprise digital display functionality for the display of data on dial22in a “digital fashion” format90. In either “movement,” a frame is provided to hold the entire structure together as one unit. Disclosure of a suitable controller, microcontroller and other hand movement components for the present invention is provided in U.S. Pat. No. 7,215,600 and the aforementioned '788 published application, the subject matter of both documents being incorporated by reference herein in their entireties. To be clear, the term “controller” is intended to comprehensively encompass all the circuitry, software and hardware to communicate with the communication device50which will be hereinafter disclosed, which in turn communicates with the external communication device, generally indicated at200, and as disclosed in the aforementioned U.S. Pat. No. 7,215,600. Moreover, the “controller” is intended to also include all the hand rotation signaling and functionality to carry out the objectives set forth herein and made apparent hereby.

In accordance with the present invention, device10comprises a radio communication device, generally indicated at50, such as a transmitter, a receiver and/or a transceiver. Communication device50may be mounted on the printed circuit board or other suitable location within watchcase15and preferably interfaces to the microcontroller100of controller30. Data is transferred to or from radio communication device50for the purpose of data display, data storage and/or control, all as is well known in the art.

In accordance with the present invention, watchcase15is preferably, but not necessarily, a continuous non-electrically conductive shell, such as plastic or ceramic. Watchcase15may be circular or square, by way of example and not limitation.

As illustrated inFIG. 1in particular, an outer conductive layer, generally indicated60, is provided on the outer surface of the watchcase15, and preferably at least extends around the perimeter of the watchcase15. If watchcase15includes a slot, then outer conductive layer60terminates at the slot. As will be understood by those skilled in the art, this outer metallic layer60acts as a radiator for electromagnetic energy. Preferably, conductive layer60is a layer of metallic paint, laser direct structuring (LDS), a solid metallic or partitioned foil, or a solid or partitioned piece of metal. Furthermore, preferably layer60covers the entire surface of the selected section of the watchcase, but covering of less than an entire surface is contemplated hereby. For example, in a preferred embodiment, conductive layer60is confined to the upper part of the watchcase, as illustrated inFIG. 1, but it is possible and within the scope of the invention that the conductive layer60extends and is applied over the entire surface of the watchcase15.

FIG. 2illustrates an alternative embodiment in which the outer conductive layer60may be embedded in the non-conductive watchcase15, having been positioned therein during the molding process of watchcase15(e.g. seeFIG. 2A). Similarly, outer conductive layer60may be a layer of metallic paint, laser direct structuring (LDS), a solid metallic or partitioned foil, or a solid or partitioned piece of metal. Here too, outer conductive layer60preferably at least extends around the perimeter of the watchcase15. If watchcase15includes a slot, then outer conductive layer60similarly terminates at the slot.

In accordance with all the preferred embodiments herein, radio communications device50is preferably coupled to a matching network55consisting of inductors and/or capacitors as would be understood in the art. Matching network55itself is electrically coupled between outer conductive layer60and a ground plane33of the PC board32. By optimum selection of the inductors and/or capacitors of matching network55at the frequency or range of frequencies at which communications device50operates, watchcase15becomes an electric field type loop antenna, all of which can be maximized by the selection of the components of matching network55. As should now be understood, excitation occurs to the antenna structure between the PC board ground plane33and the outer conductive layer60in both embodiments ofFIGS. 1 and 2.

The loop configuration created by the antenna structure comprising outer conductive layer60, the inner conductive layer preferably comprising the ground plane33of the PC board32, and matching network55creates a form factor that efficiently radiates energy and receives radiated energy. The unique approach with the preferred embodiments of the present invention is the optimum match of communications device50to outer conductive layer60, which becomes the radiating element.

As would be understood by those skilled in the art, metal in proximity of outer conductive layer60can affect the ability of the antenna's performance. And, since any deviation from the loop form factor such as the addition of a metal case back would detract from the loop's ability to radiate waves or receive radiated waves, case back25is comprised of a form factor that maintains the loop configuration. This is achieved most easily by using a non-electrically conductive case back such as glass, ceramic and/or plastic which does not significantly impede radiation. It can also be comprised of a nonmetallic material in the center of the case back and a metallic material on the perimeter of the case back, effectively maintaining the loop configuration. Here again, dial22is preferably configured from non-conductive material to minimize any negative effects to transmission or reception.

It should also be understood however that the incorporation of matching network55is somewhat optional, as the antenna structure can also be left unmatched depending on the desired antenna characteristics particular for each design.

It can thus be seen that the present invention provides an improved antenna structure for a wristworn device having improved signal transmission and reception functionality utilizing a non-electrically conductive watchcase that has been provided with an outer metallic layer60that acts as a radiator for electromagnetic energy, wherein the conductive layer60is preferably a layer of metallic paint, laser direct structuring (LDS), a solid metallic or partitioned foil, or a solid or partitioned piece of metal on the surface of the watchcase or alternatively, the outer conductive layer60may be embedded in the non-electrically conductive watchcase15.

It will thus be seen that the objects set forth above, among those made apparent from the preceding description, are efficiently attained and, since certain changes may be made in the above constructions without departing from the spirit and scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense. It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention described herein and all statements of the scope of the invention which as a matter of language might fall therebetween.