Abstract:
A data processing system is proposed which comprises two electronic devices, each of them having an electro-magnetic coupler embedded on the exterior casing, at least one of the electronic device having one or more sliding surfaces for directing relative movement between the two devices, such that they automatically come into correct alignment during the sliding.

Description:
TECHNICAL FIELD 
       [0001]    The invention relates to a data processing system which comprises at least two electronic devices, and in particular relates to how the devices are connected to each other for data transfer between them. One or both of the electronic devices may be, but are not limited to, mobile devices such as cameras and smart-phones and corresponding devices such as display instruments, storage drives and any other devices for processing data. 
       BACKGROUND OF INVENTION 
       [0002]    There are many situations requiring data exchange between devices via efficient and reliable channels. Conventional means of connecting multiple devices include using cable or connectors (such as a USB connection), through which data are communicated. However, wired links are not compatible with the ever-increasing need for a more convenient and readily establishable connection between two devices. This is because it is always necessary to manually align and connect the connector(s) to the port of the device(s). Wear of the connectors and connection ports is also a problem. 
         [0003]    Besides wired connections, wireless protocol such as Bluetooth and infrared protocols are also available for data communication between two devices. Wireless connection channels bring the benefit of simple connecting procedures since two devices can conveniently communicate with each other remotely without any physical connection in between. Thus, no manual alignment of the connector and port is necessary, and data is communicated through the electro-magnetic (EM) waves travelling freely through space. On the other hand, since wireless communication has less transmission directivity. Energy loss and low transmission efficiency are a problem for wireless communication over a long distance. More importantly, there have been increasing concerns about the harmful side effects of such EM emission on the human body. 
         [0004]    It is desirable to provide a convenient, wear resistant and hassle-free communication channel between electronics devices, eliminating connecting wires and their connectors while minimizing EM emission losses. Close contact data communication had been explored in recent years. In this case, two electronic devices are brought in contact with each other at an intended location to allow the EM couplers located on the exterior casing of each device to be aligned thereby establishing surface connection for data communication. However, this usually requires some form of manual alignment between the two devices/couplers. Conventionally, the alignment is achieved either through mechanical guides or slotted plugs. 
         [0005]    Therefore, it would be desirable to have a coupling technique such that when a user casually leaves a mobile device such as a camera or a smart-phone on a corresponding device such as a display instrument or a storage drive, two couplers of the respective devices become automatically aligned, without the user consciously aligning the devices accurately. As such, robust data communication could be achieved through the surface contact. 
       SUMMARY OF INVENTION 
       [0006]    In general terms, the invention proposes a data processing system comprising two electronic devices, each of them having an electro-magnetic coupler embedded on the exterior casing, at least one of the electronic device having one or more sliding surfaces for directing relative movement between the two devices, such they automatically come into correct alignment during the sliding. The casings of the devices may be made of plastic. 
         [0007]    Specifically, there is provided a data processing system comprising:
       a first electronic device having one or more data processors, a first casing enclosing said one or more data processors and a first data transfer electro-magnetic coupler located on said first casing, and   a second electronic device having one or more data processors, a second casing enclosing said one or more data processors and a second data transfer electro-magnetic coupler located on said second casing,   at least one of said first and second electronic device comprising a plurality of sliding surfaces for directing relative movement between the first and second electronic devices, at least two of said sliding surfaces being mutually inclined,   wherein upon the first and second electronic devices being urged together by a force in a direction inclined to at least one said sliding surface, one of the electronic devices slides along said at least one said sliding surface to bring said data transfer electro-magnetic couplers into alignment,   whereby said first electronic device is automatically positioned with respect to said second electronic device and with the couplers in alignment, and surface connection is established between the couplers at the point of alignment to enable high speed data communication between the two electronic devices.       
 
         [0013]    The term “inclined” is given its conventional meaning of “neither parallel to, nor orthogonal to”. The force being in a direction inclined to a surface means that the force is in a direction which has an angle greater than 0 and less than 90° relative to the normal direction of the surface. Preferably, the angle is in a range from 10° to 80°, or 20° to 70°. Two sliding surfaces being mutually inclined means the normal directions of the two surfaces are neither parallel to, nor orthogonal to each other. A generally non-flat or curved surface is considered to comprise an infinite number of mutually inclined surfaces. 
         [0014]    Typically, the force is the gravitational force that said one of the electronic devices is subject to. 
         [0015]    Unlike a mechanical guide, which defines an unambiguous path along which the two devices may approach each other, a sliding surface defines a range of options of such paths. For example, the two devices may be casually brought into contact with each other at any point along the sliding surface, and the sliding surface will direct relative movement between the two devices and allow one of them to slide along the other and stop at an intended location automatically without manual intervention. Advantageously, the couplers located on the casing of two devices can be brought aligned face to face naturally and automatically under the influence of the weight of the device, without requiring external loads, supplementary alignment supports or clamping tools. Such surface connection facilitates EM waves to travel between them, while maximizing transmission directivity and minimizing radiation leakage. 
         [0016]    Typically, each of the first and second electronic devices further comprises one or more magnets for generating a component of said force. Typically, the magnets are configured such that the electro-magnetic signals between the couplers are shielded from magnetic interference. 
         [0017]    Advantageously, the magnetic attraction between the two devices effectively helps bring the electronic devices to full contact at an intended location without using external instrument or mechanical guides. The attraction further enhances stability of the surface connection between the two couplers. 
         [0018]    The sliding surface is typically inclined to the overall profile of the casing on which it is provided. For example, many casing have a generally cuboidal profile (convex hull), and the normal direction to at least one sliding surface is inclined to each face of the cuboid. 
         [0019]    In one embodiment, said first electronic device has a planar surface and said second electronic device comprises a depression having a sloping side wall and a bottom surface, said side wall and the bottom surface being the sliding surfaces, said depression having a shape configured to receive said first electronic device. 
         [0020]    In another embodiment, said second electronic device comprises a face and one or more projections projecting therefrom, said face and the surface of said one or more projections being said sliding surfaces, said sliding surfaces being arranged to stop relative movement of the two electronic devices at a position where the two couplers are in alignment when the face is upright. Typically, there are a plurality of said projections, said plurality of elements being arranged in a pattern suitable for said first electronic device to rest thereon when the face is upright and the couplers are in alignment. Typically, the projections have a frustum shape. Typically, the cross-sectional area of said projections reduces towards said face. 
         [0021]    The term “upright” is given a conventional meaning as being “generally vertical”. A face being upright generally means the normal of the face has an angle in the range of 0-20°, or more preferably 0-10° with respect to the horizontal. 
         [0022]    In still another embodiment, said first electronic device comprises a protrusion having a curved surface and said second electronic device comprises a depression having a shape configured to receive said protrusion of said first electronic device. Typically, said first electronic device comprises a protrusion having a hemispherical shape. Typically, said depression has a smooth concave shape. 
         [0023]    In still another embodiment, said first electronic device comprises a protrusion having a frustum shape and said second electronic device comprises a depression having a shape being configured to receive said protrusion of the first electronic device. Typically, said depression has a frustum shape. 
         [0024]    In any of the above embodiments the two couplers may be flat. At least one sliding surface is typically inclined to the plane of the couplers. 
         [0025]    In any of the above embodiments one of the electronic devices may be a portable/mobile electronic device while the other may be non-portable/fixed electronic device. Alternatively, both devices may be mobile devices. Furthermore, the invention is applicable to situations with additional electronic devices, i.e. three or more devices in total, e.g. a large fixed electronic device receiving two mobile electronic devices. The electronic devices may ones which are made and sold separately, e.g. by different manufacturers. Thus, from another point of view, the invention may be defined as a single electronic device, arranged for connection to a second, and separately provided, electronic device. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0026]    It will be convenient to further describe the present invention with respect to the accompanying drawings that illustrate embodiments of the invention. Other embodiments of the invention are possible, and consequently the particularity of the accompanying drawings is not to be understood as superseding the generality of the preceding description of the invention. 
           [0027]      FIG. 1  is a schematic view shows the cross-section of the data processing system according to one embodiment of the invention. 
           [0028]      FIG. 2  is a schematic view of the data processing system according to another embodiment of the invention. 
           [0029]      FIG. 3  ( a ) is a schematic view shows the cross-section of the data processing system according to a third embodiment of the invention. 
           [0030]      FIG. 3  ( b ) is a schematic view shows the cross-section of the data processing system that is a modified embodiment based on the third embodiment. 
       
    
    
     DETAILED DESCRIPTION 
       [0031]      FIG. 1  shows a data processing system  100  comprising a first data processing device  101  having a first electro-magnetic coupler  102  located on the exterior casing of the first device  101 , and a second data processing device  104  having a second electro-magnetic coupler  106  located on the exterior casing of the second device  104 . The casing of the first device  101  has a planar surface  108  on which the coupler  102  is located and the casing of the second device  104  has a depression. As shown in  FIG. 1 , the depression has sloping side walls  110 ,  112  and a planar bottom surface  114  to receive the first device  101 . The side walls  110 ,  112  are inclined to the bottom surface  114 . Therefore, when a user casually leaves the first electronic device  102  on any part of the depression of the second device  104 , the first device  101  will slide along one of the sloping side walls  110 ,  112  and the bottom surface  114  due to gravity and sink to the bottom surface  114 . Thus, the two couplers  102 ,  106  of the two devices  101 ,  104  are brought into face-to-face alignment whereby high speed data communication is established at their touching surface. In this embodiment, the sloping side walls  110 ,  112  and the bottom surface  114  are the sliding surfaces and the side walls  110 ,  112  are also inclined to the direction of the gravitational force. Preferably, the first device  101  is more compact and lighter than the second device  104 . Preferably, the shape and size of the bottom surface  114  matches that of the surface  108  of the first device  101 . Note that, at least two of the sliding surfaces  110 ,  112 ,  114  are mutually inclined. 
         [0032]      FIG. 2  shows another embodiment of the invention in which the contact surface of two devices is upright. A data processing system  200  comprises a first data processing device  201  having a first electro-magnetic coupler  202  located on the exterior casing the first device  201 , and a second data processing device  204  having a second electro-magnetic coupler  206  located on the exterior casing the second device  204 . The casing of the second device  204  has a generally upright face  208  on which the coupler  206  is located, and one or more projections  210  projecting from the face  208 . As shown in  FIG. 2 , when there are a plurality of projection, the projections  210  are arranged in a pattern suitable for the first device to rest thereon when the face  208  is upright and couplers  202 ,  206  are in alignment. The upper surfaces of the projections are inclined upwards from the horizontal direction. When a user places the first device  201  on the projections  210 , the first device  201  will slide downwards along the upper surfaces of the projections  210  due to gravity and eventually stop at an intended location on the face  208 . Alternatively, when a user places the first device  201  on the face  208 , the first device  201  will first slide downwards along the face  208  and then be directed to stop at the intended location after sliding along the surfaces of projections  210 . As such, the two couplers  202 ,  206  of the two devices are brought into alignment whereby high speed data communication is established at their touching surface. In this embodiment, the upper surfaces of the projections  210  and the face  208  are the sliding surfaces. Note that at least the upper surfaces of the projections  210  are inclined to the direction of gravitational force. Also, at least two of the sliding surfaces are mutually inclined. 
         [0033]    It should be noted that the multiple projections  210  as shown in  FIG. 2  are an exemplary illustration of the possibility of having more than one projection. It is also possible that the face  208  only has a single projection provided it is arranged to direct and stop relative movement of the two electronic devices at the intended location described above. 
         [0034]    Preferably, the first device  201  is more compact and lighter than the second device  204 . The projections  210  may have a frustum shape whose cross-sectional area may reduce towards the face  208 . Therefore, the upper surface of the projections  210  collectively form a slope that allows the first device  201  to slide towards the face  208  of the second device  204  and collectively support the first device  201  thereon. 
         [0035]      FIG. 3(   a ) shows the third embodiment of the invention. It comprises a first data processing device  301  having a first electro-magnetic coupler  302  located on the exterior casing the first device  301  and a second data processing device  304  having a second electro-magnetic coupler  306  located on the exterior casing the second device  304 . The casing of the first device  301  comprises a protrusion  308  having a frustum shape and the casing of the second device  304  comprises a depression having a shape to receive the protrusion  308  of the first device  301 . The depression may have a frustum shape with sloping side walls  310 ,  312  being inclined to a bottom surface  314 . When a user places the protrusion  308  of the first device  301  onto any part of the depression of the second device  304 , the first device  301  will slide along one of the sloping side walls  310 ,  312  and the bottom surface  314  due to gravity and sink to the bottom surface of the depression. In this embodiment, the side walls  310 ,  312  and the bottom surface  314  are the sliding surfaces. As such, the two couplers  302 ,  306  of the two devices are brought into alignment whereby high speed data communication may be established at their touching surface. Advantageously, the weight of the first device  301  presses both couplers firmly due to their small surface contact area (in contrast to the first embodiment in which the weight of the first device  101  is distributed over the whole face  108 ). At least two of the sliding surfaces  310 ,  312 ,  314  are mutually inclined. 
         [0036]      FIG. 3(   b ) shows a slightly modified embodiment from that of  FIG. 3(   a ). In this embodiment, the casing of the first electronic device  301  comprises a protrusion  318  having a curved surface which is generally flat at the bottom, and the casing of the second device comprises a depression having a shape to receive the protrusion  318 . The protrusion  318  may have a hemispherical shape with a generally flat bottom surface and the depression may have a smooth concave shape with a generally flat bottom surface. The diameter of the concave depression may be larger than that of the hemispherical protrusion  318  except at the bottom surface. Advantageously, this allows the protrusion  318  to slide along the side walls of the depression more gently and smoothly compared to the embodiment with a frustum-shaped protrusion  308  (as shown in  FIG. 3(   a )). In this embodiment, the surface profile of the depression is generally curved and is thus considered to comprise an infinite number of mutually inclined sliding surfaces. Optionally, the depth of the depression matches the height of the protrusion  318 . Optionally, depending on the size of the couplers  302 ,  306 , the flat bottom surface of the protrusion  318  and the depression can be adjusted such that each of the couplers  302 ,  306  fits horizontally in the centre of the bottom surfaces, respectively. 
         [0037]    In any of the above embodiments, each of the first and second devices may comprise one or more small magnets thereby providing magnetic attraction to further drive relative movement between the two devices and enhance the stability of the alignment of the two couplers. Preferably, the magnets are configured such that the electro-magnetic signals communicated between the couplers are shielded from magnetic interference due to the magnets. This may be achieved by using any common methods of restricting/redirecting magnetic field. For example, at least one metal plate (yoke) can be provided (eg. attached to the magnet) to confine the magnetic flux such that electronic circuits within the first and/or second devices can be protected from undesired disruption. The yoke(s) may be between the magnet and the electronic circuits. The yoke may be a thin metal plate. In any of the above embodiments, the two couplers may be flat. 
         [0038]    When the first device is automatically positioned with respect to the second device and with the couplers in alignment, surface connection is established between the couplers at the point of alignment to enable robust data communication between the two devices. Both couplers stay in full contact throughout the data communication operation. 
         [0039]    The present disclosure contains subject matter related to that disclosed in Singapore Priority Patent Application SG 201203884-0 filed in the Intellectual Property Office of Singapore on May 24, 2012, the entire content of which is hereby incorporated by reference. 
         [0040]    The embodiments have been described by way of example only and it will be appreciated that various modifications in detail may be made to the described embodiments above without departing from the spirit and scope of the claims.