Field

The present invention relates to an optical wireless communication connector device. Background

It is known to provide wireless data communications by using light instead of radio frequencies to transmit and receive data wirelessly between devices. Data may be transmitted using light by modulating at least one property of the light, for example an intensity of the light. Methods that use light to transmit data wirelessly may be referred to as optical wireless communications (OWC) or light communications (LC). One method that uses light to transmit data wirelessly is LiFi.

Wireless networks using visible light may in some circumstances allow a higher data capacity, greater energy efficiency and greater security than radio frequency wireless networks, and may also be used to replace point-to-point infrastructure in locations where conventional infrastructure does not exist or is too expensive to build.

Optical wireless communication may provide simultaneous wireless communication and illumination from luminaires (for example, LED luminaires) that may traditionally only be utilised for lighting purposes. Optical wireless communication in such cases may be provided by modulating, for example, an intensity of the light produced by the luminaires so that data that is to be transmitted is represented by the modulation of the light. Usually the modulation of the light occurs at such a frequency that it is imperceptible to the naked eye.

Optical wireless communication may normally provide line-of-sight communication between two compatible devices, each of which includes a light transmitter and/or receiver. A non-compatible device, for example a non-OWC enabled laptop or other computing device may be converted to a compatible device by connecting an optical wireless communication enabling device, for example a dongle, to the non-compatible device. The connection can be through a standard data interface, for example a Universal Serial Bus (USB) interface and the optical wireless communication enabling device include at least a transmitter and/or receiver for transmitting and/or receiving light at the wavelength or range of wavelengths used in the optical wireless communication process.

However, as optical wireless communication is typically a line-of-sight technique movement of the non-compatible device, together with the enabling device, may be detrimental to signal quality of a wireless optical communication connection. This may be an issue in particular for laptops or other portable computing devices.

Summary

According to an aspect of the present invention, there is provided a wireless optical communication connector device comprising:

at least one of a transmitter configured for optical wireless communication and a receiver configured for optical wireless communication, wherein at least one of the transmitter or receiver is configured for optical wireless communication using visible light;

a connector member comprising a male or female connector for detachable insertion into a corresponding female or male connector to provide a data interface between the device and a further device;

an orientable member comprising at least one of the transmitter and the receiver;

a rotation mechanism operable to provide rotation of the orientable member relative to the connector about a rotation axis and to maintain the orientable member in a rotated position following completion of said rotation. At least one of the transmitter and the receiver may be positioned on the orientable member such that, when inserted, the device is operable to orient the at least one of the transmitter and the receiver to face substantially upwards.

The use of a rotation mechanism that can be operable to provide rotation of the orientable member relative to the connector about a rotation axis substantially parallel to a longitudinal axis of the connector may be particularly useful for a dongle or similar device that may be used to adapt a laptop or other portable device for optical wireless communication. The rotation mechanism may be operable to orient a field of view of the transmitter and/or receiver upwards or downwards with respect to a plane defined with respect to a longitudinal axis of the connector and hence, in use, with respect to a corresponding plane of the further device to which the connector device may be connected. Thus, for example, if the connector device is connected to a laptop or similar device the rotation mechanism may be used to orient a transmitter and/or receiver upwards to be directed towards a luminaire unit, for example a ceiling mounted luminaire unit, that is being used for optical wireless communication. The connector may comprise a universal serial bus (USB) connector. The universal serial bus connector may be one of a standard USB size, mini USB size or micro USB size.

The rotation axis may be substantially parallel to a longitudinal axis of the connector. The device may be configured such that at least one of the transmitter and the receiver has a field of view that may be varied over at least 360 degrees with respect to the longitudinal axis by rotation of the orientable member using the rotation mechanism.

The connector may comprise a plurality of electrical connections extending substantially parallel to a plane that extends parallel to the longitudinal axis. The at least one of the transmitter and the receiver may be positioned on the orientable member such that the rotational mechanism is operable to orient the at least one of the transmitter and the receiver to face in a direction substantially orthogonal to said plane. The rotation mechanism may be configured such that the orientable member is rotatable around said rotation axis by at least 90 degrees, optionally at least 180 degrees, optionally at least 270 degrees, further optionally at least 360 degrees.

The rotation mechanism may be operable to provide rotation of at least part of the orientable member relative to the connector member with respect to the rotation axis and with respect to a further axis orthogonal to said rotation axis.

The rotation may comprise a sum of rotations around said axis and said further axis. Thus the rotation of the orientable member may have at least two degrees of freedom. The connector member and/or the orientable member may be substantially rigid.

The orientable member may comprise a first portion and a second portion, and the second portion may be orientable relative to the first portion.

The first portion may be rotatably coupled to the second portion.

The first portion may be orientable by rotation relative to the connector member about a first axis by a first range of angles and the second portion may be orientable by rotation relative to the first portion about a second axis by a second range of angles. The first axis may be substantially orthogonal to the second axis or the first axis may be substantially parallel to the second axis. The first and second axes may be collinear such that the second portion is operable to rotate about an angle equal to the sum of the first angle and the second angle.

Orientation of the orientable member may comprise rotation of the first portion and rotation of the second portion. The transmitter may be provided on the first portion and the receiver may be provided on the second portion. The transmitter may be provided on the second portion and the receiver may be provided on the first portion.

One of the transmitter or the receiver may be provided on the second portion.

Both the transmitter and the receiver may be provided on the second portion.

The orientable member may be manually orientable by a user. The device may further comprise a drive arrangement to orient the orientable member, wherein the drive arrangement is electrically, magnetically and/or electro-magnetically powered. The device may further comprise a controller configured automatically to control orientation of the orientable member. The controller may be configured to control orientation of the orientable member based on at least one of:

a) signal strength of at least one signal received at the receiver or transmitted by the transmitter;

b) a control signal received from the further device or at least one additional device;

c) a measurement of orientation of the orientable device and/or the further device and/or a measurement of relative orientation of the orientable device and the further device.

The transmitter may comprise at least one light transmitting element and/or the receiver may comprise at least one light receiving element. The at least one light transmitting element may comprise at least one of a lens, concentrator, mirror, light guide or other optical component. The at least one light receiving element may comprise at least one of a lens, concentrator, mirror, light guide or other optical component. The device may further comprise an LED or other component for converting electrical signals to light signals. The device may comprise an optical connection for transmitting light to the orientable member for transmission by the at least one light transmitting element. The LED or other component for converting electrical signals to light signals may be located on the connector member or other component separate from the orientable member.

The device may further comprise a photodiode or other photodetector. The device may comprise an optical connection for transmitting light received by the at least one light receiving element from the orientable member to the photodiode or other photodetector. The photodiode or other photodetector may be located on the connector member or other component separate from the orientable member.

Alternatively, the receiver included in the orientable member may comprise a photodiode or other photodetector and/or the transmitter included in the orientable member may comprise an LED or other component for converting electrical signals to light signals.

The device may further comprise an indicator for indicating signal strength of signals received at the receiver and/or transmitted by the transmitter.

The device may comprise a visual indicator, for example, a light or a display. The indicator may be configured to provide an indication signal in response to signal strength being greater than or equal to a threshold value.

The device may further comprise: an optical wireless communication processor provided in the connector member or the orientable member and configured to at least one of: control operation of the transmitter to produce modulated light comprising an optical wireless communication signal; process signals received from the receiver to obtain data represented by an optical wireless communication signal included in light received by the receiver.

The data interface may be configured to send signals between the device and an optical wireless communication processor included in the further device, and the optical wireless communication processor may be configured to at least one of:

control operation of the transmitter to produce modulated light comprising an optical wireless communication signal; process signals received from the receiver to obtain data represented by an optical wireless communication signal included in light received by the receiver.

A device according to any preceding claim, further comprising at least one of a digital to analogue convertor for conversion of signals provided to the transmitter or an analogue to digital convertor for conversion of signals obtained from the receiver. The device may be a dongle.

The further device may comprise at least one of a mobile and/or hand-held computing device, a smartphone, a mobile phone, a tablet, a computer, a laptop, an access point. The transmitter may be configured to transmit modulated light and/or the receiver may be configured to receive modulated light, he modulated light may comprise at least one of infra-red radiation, ultra-violet radiation, visible light. The transmitter may be configured to emit light at a first wavelength and/or the receiver may be configured to receive light at a second wavelength. The transmitter may be configured to produce an infrared signal. The transmitter may comprise an infrared diode. The receiver may be configured to receive a visible light signal. The receiver may comprise a photo diode.

The at least one transmitter and/or receiver may have associated optical components, for example a lens or concentrator, for directing light from the transmitter and/or to the receiver. Any feature in one aspect of the invention may be applied to other aspects of the invention, in any appropriate combination. For example, apparatus features may be applied to method features and vice versa.

Brief Description of the Drawings

Various aspects of the invention will now be described by way of example only, and with reference to the accompanying drawings, of which:

Figure 1 is a schematic diagram of an optical wireless communication enabling device;

Figure 2 is a perspective view of a first embodiment of an optical wireless communication device;

Figure 3 is an expanded perspective view of the first embodiment of the optical wireless communication device;

Figure 4 is a schematic diagram showing the device in a first configuration and a second configuration;

Figure 5(a) is a perspective view of a second embodiment of the optical wireless communication device in a first configuration and Figure 5(b) is an expanded perspective view of the second embodiment of the optical wireless communication device in a second configuration;

Figure 6(a) is a perspective view of a third embodiment of the optical wireless communication device in a first configuration and Figure 6(b) is an expanded perspective view of the second embodiment of the optical wireless communication device in a second configuration, and

Figure 7 is a perspective view of a fourth embodiment of the optical wireless communication device in a first configuration.

Detailed Description

Light may be used, for example, to refer to electromagnetic waves with wavelengths in a range 1 nm to 2500 nm, which includes ultraviolet, visible light and near-infrared wavelengths.

Figure 1 is a schematic block diagram showing components of an optical wireless communication connection device 20 according to an embodiment. The device 20 in this embodiment is a dongle for enabling optical wireless communication in a further device. In the present embodiment, the further device is a laptop or other host computer 30, but any other suitable further device may be provided in other embodiments. The device 20 is insertable into the further device 30. The device is configured to enable or enhance optical wireless communication channel in the further device and/or to enhance roaming capability.

As described in more detail below, the device 20 includes a transceiver mounted on an orientable member 24 and comprising a transmitter 40 and a receiver 42. The orientable member is orientable to find an optimum angle for communication by the transceiver with a remote device, for example, an access point for providing data transmission to and/or from a wired network or a WiFi or other r.f. wireless network or for providing transmission to and/or from an optical wireless communications network, optionally a LiFi network.

The device 20 has a connector member 22 and an orientable member 24. The connector member 22 connects the device via a USB connector 26 to the host computer 30. The connector member 22 thus provides a data interface, in this example a USB interface, between the device 20 and host computer 30. Any other suitable detachably insertable male or female connector may be used in other embodiments. The host computer 30 can be any suitable computing device. The host computer 30 is a further device, for example, a mobile and/or hand-held computing device, a mobile phone, a tablet, a computer, a laptop, an access point or any other suitable computing device. The host computer 30 has a further processor 48. The device 20 communicates with the further processor 48 through the USB interface. The device 20 has two main structural components connected together by a third structural component. The first component is the connector member 22 that accommodates the USB connector 26 that is insertable into a corresponding socket of the host computer 30 and provides the USB interface. The second component is the orientable member 24 that accommodates the transceiver 40, 42 for optical wireless communication. Alternatively, the orientable member 24 may accommodate a receiver but no transmitter, or a transmitter but no receiver, in some embodiments.

The coupling member 32 couples the two components together, mechanically and electronically. Analogue circuitry for the transceiver is contained in the orientable member 24 and associated digital circuitry is contained in the connector member 22. In other embodiments, analogue circuitry may be contained in the orientable member 24 or in the connector member 22, or may be divided between the orientable member 24 and the connector member 22. The digital circuitry may be contained in the orientable member 24 or in the connector member 22, or may be divided between the orientable member 24 and the connector member 22.

The coupling member provides an interface for digital signals between the connector member 22 and the orientable member 24. The orientable module 24 is moved using a drive mechanism 34. The drive mechanism may be located in at least one of the connector member 22, the coupling member 32 and the orientable member 24.

By providing analogue circuitry in the orientable member 24 and digital circuitry in the connector member 22, fewer connections need to be provided in the joining coupling member 32. For example, only twelve connections (for example, twelve analogue connections) may need to be provided in some embodiments. In one example, the connections in the coupling member 32 comprise at least some of: differential pair, ground and 5V, -30V (providing connections that may be used by the receiver in the orientable member 24), and differential pair, rail voltage, and two I2C bus connections (providing connections that may be used by the transmitter in the orientable member 24). In some embodiments, communications between the portions of the dongle (for example, between the connector 22 and the coupling member, between the coupling member and orientable member 24, or between the connector 22 and orientable member 24 directly) may be provided via light. In some embodiments, positioning of at least one portion of the dongle is controlled and powered via a battery or via a photovoltaic power source. Data may be transferred optically within the dongle, which may maintain speed. In some embodiments, communications may be provided via inductance. Communications between portions of the dongle may be wire-free.

The USB connector 26 may be any type of USB hardware connector. As a non-limiting list of examples, the connector 26 may be a male or a female USB connector, USB type A, USB type B, USB mini A, USB mini B, USB micro A or USB micro B. The connector may be USB type C. The USB interface may be USB-1.0, USB-2.0 or USB- 3.0 or any other suitable USB interface.

The device 20 has a processing module 36 located in the connector member 22. The processing module 36 has a processing resource 38 for processing optical wireless communication data signals and a control module 41 for sending control signals to the drive mechanism 34. In some embodiments, the processing resource 38 and the control module 41 are in communication with each other. The coupling member 32 has a connector data interface 39 permitting data signals to be communicated between the circuitry of the connector member 22 and the circuitry of the orientable member 24.

The orientable member 24 includes a transceiver 40, 42 and associated analogue front end circuitry. The transceiver is represented in Figure 2 by a transmitter 40 and a receiver 42. In some embodiments, the transmitter may be, for example, an infrared light emitting diode (LED). The receiver 42 may be, for example, a photodiode. The receiver 42 is configured to receive light signals at a first wavelength, visible light in this embodiment, and the transmitter 40 is configured to transmit at a second different wavelength, infrared light in this embodiment.

The transmitter 40 has an associated analogue front end 44 which contains an associated driving circuit to drive the LED to produce the optical signal. The associated driving circuitry includes a digital to analogue convertor configured to provide a modulation signal at a frequency characteristic of an optical light communication signal. The analogue front end modulates a drive current using data and the driving circuitry provides the drive current to the LED. The LED then produces an outgoing modulated optical wireless communication signals that carries the data. The photodiode of the receiver 42 has an associated analogue front end 46 which contains conditioning circuitry. The photodiode converts received light to an electronic signal which is then conditioned by the conditioning circuitry of the analogue front end 46. Conditioning includes one or more filter steps; amplification of a weak electrical signal; equalisation of received signals and converting the analogue signals into digital signals using an analogue to digital convertor. The digital signals can then be provided to a further processor, for example the processing resource 38 of the connector member, to be demodulated to extract communication data.

Figure 2 shows the first embodiment of the optical wireless communication device 20 in an initial configuration. Figure 2 shows the connector member 22, the orientable member 24 and the USB male connector 26 held by the connector member 22. An optical transceiver having the optical transmitter 40 and optical receiver 42 is provided on the orientable member 24. In other words, the device has a body comprising the connector member 22 and a rotatable head comprising the orientable member 24.

The connector member 22 is substantially rigid. The orientable member 24 is substantially rigid. The connector member 22 has an upper and lower surface, two side surfaces and a front and back surface. Likewise, the orientable member 24 has corresponding surfaces: an upper and lower surface, two side surfaces and a front and back surface. In the initial configuration of Figure 2, each surface of the connector member 22 is flush with its corresponding surface of the orientable member 24. The connector member 22 has a length defined at its end points by the front and back surface. A longitudinal axis can be drawn along the length of the connector member 22 connecting the central points of the front and back surface of the connector member 22 such that the connector member surrounds the longitudinal axis.

The orientable member 24 has a length that extends along the longitudinal axis and the connector member 22 and orientable member are arranged such that the back surface of the connector member faces the front surface of the orientable member 24. The USB connector 26 is provided in a substantially central position of the front surface of the connecter member 26, substantially along the longitudinal axis. The longitudinal axis defines an orientation axis, or axis of rotation, for the orientable member 20.

Between the connector member 22 and orientable member 24 is the coupling member (not shown) that provides a mechanical coupling between the connector member 22 and the orientable member 24. The mechanical coupling provides a rotation mechanism allowing the orientable member 24 to be operable to rotate about the orientation axis and then to maintain the orientable member in a rotated position following completion of the rotation. The orientable member 24 is operable to move from a first orientation of a plurality of rotated orientations to a second orientation of the plurality of rotated orientations. The mechanical coupling also has at least one stop for retaining the orientable member in a rotated orientation. Any other rotation mechanism may be provided in alternative embodiments. In some embodiments, the coupling member comprises a ratchet mechanism. The ratchet mechanism may be driven manually or electronically. In some embodiments, the orientable member 24 may be pulled apart from the coupling member and reinserted into the coupling member in order to manually reposition the orientable member 24 relative to the coupling member.

In some embodiments, the coupling member comprises a geared wheel, for example a geared wheel that is configured to move under the control of the control module. In some embodiments, the coupling member comprises a gear that is coupled with a wedge on a spring. Motion control may be used to keep the electrical connection intact. In other embodiments, slip rings may be used to provide the electrical connection between the coupling member and orientable member 24.

Each orientation of the plurality of rotated orientations can be characterised by an angle measured from a reference orientation. A suitable reference orientation is provided by the orientation of the orientable member 24 in the initial configuration. Another suitable reference orientation may be provided by the position of one of the connector, the connector member or any other fixed part. The characteristic angle of the rotated orientation may be in the range 0 to 360 degrees, as measured from the initial configuration. The coupling member may also restrict rotation available orientations for the orientable member. For example, the characteristic angle may be restricted to be less than 180 degrees clockwise and less than 180 degree anti-clockwise measured from the initial configuration. In a further example, the characteristic angle may be restricted to be less than 90 degrees clockwise and less than 90 degrees anti-clockwise from the initial configuration. The coupling member also includes the physical data link 39 that provides a connector data interface between the circuitry of the orientable member 24 and the circuitry of the connector member 22. Figure 3 shows an expanded view of the first embodiment of the optical wireless communication device 20 in a rotated configuration, where the orientable member 24 is rotated relative to the connector member 22 about the orientation axis. The orientable member is fixed in an orientation such that the transceiver is titled towards the direction of the access point.

Figure 4 is a schematic cross-sectional view of the orientable member 24 of the device 20 in the initial configuration (solid black line) and in the rotated configuration (dotted black line). The view of Figure 4 is taken along the longitudinal axis of the device 20. Figure 5 also shows an optical wireless communication access point 50 with an access point transmitter 52 and an access point receiver 54. The access point 50 may provide an interface to enable communication of data between the device 20 and a wired network, for example an Ethernet network, or a further wireless network, for example an r.f. wireless network. The access point may operate according to known techniques. In the initial configuration, the transceiver has a first field of view surrounding a first direction, through which a first optical communication field 51 a is emitted. The first direction is substantially normal to the upper surface of the connector member 22, not shown in Figure 5, and substantially normal to the upper surface of orientable member 24. In the rotated configuration, the transceiver has a second field of view surrounding a second direction, through which a second optical communication field 51 b is transmitted. The second direction is substantially normal to the upper surface of the orientable member 24 in the rotated orientation and rotated relative to the upper surface of the controller member 24. The device 20 and access point 50 can communicate via an optical communication channel. The optical communication channel may be bi-directional and comprise an uplink 56 and a downlink 58. Operation of the optical communication channel may be full duplex or half duplex. The optical communication channel is formed as follows.

The optical light communication field 51 a is emitted from the device 20 from the device transmitter 40 as shown in Figure 4. The device 20 is positioned such that the receiver 54 of the access point 50 is in the optical wireless communication field 51 a. In this position, the access point 50 can receive an optical communication signal sent by the mobile device 20. For example, for device 20 in the initial configuration, an uplink 56a is formed between the transmitter 40 and the access point 50. In a further example, for device 20 in the rotated configuration an uplink 56b is formed between the transmitter 40 and the access point 50. The transmitter 52 of the access point 22 can emit a further optical communication field carrying data in the form of optical communication signals. The emission of the further optical communication field by the transmitter 52 of the access point 22 may be simultaneous with the emission of the optical light communication field 51a from the device 20. The mobile device 20 is positioned in the further optical communication field and can be linked to the access point 50 and receive a signal carried on the further optical communication field. The device 20 is positioned such that the receiver 42 is in the further optical communication field and then the device 20 can receive an optical communication signal sent by the access point 50. For example, for the device 20 in the rest orientation the receiver 42 of the device 20 is in the further optical communication field and a downlink 58a is formed between the transmitter 52 of the access point 50 and the device 20. In a further example, for device 20 in the rotated configuration a downlink 58b is formed between the transmitter 40 and the access point 50. As described above, the device 20 is operable to move between the initial configuration and the rotated configuration. Movement between a first configuration and a second configuration may be manual, for example by end-user manipulation. Alternatively, or in addition, movement may be by electro-mechanical means, under software and/or electronic control. The movement between a first configuration and a second configuration may also be automatic. The control module 41 controls a drive mechanism 34 that drives the rotation of the orientable member 24.

The drive mechanism 34 may be electrically, magnetically and/or electro-magnetically powered.

In a non-automatic electro-mechanical implementation, control signals may be provided by the host computer 30 via the USB interface cable 26 based on input to the host computer by a user. A user provides user input via an interface to the host computer which is processed by software running on the host processor 48. The host processor 48 then instructs the control module 41 to rotate the orientable member through a certain angular distance.

In a second implementation, suitable control signals are automatically generated by the processing resource 38 or by the host processor 48 based on one of received optical signal strength, received optical signal speed and/or a further signal.

The further signal may be indicative of the position of the access point 50 relative to the device 20. The further signal may originate from another sensor provided on the device. For example, the device may have an accelerometer integrated circuit that provides a signal containing information confirming that the device is moving and the device orientation.

Alternatively, the further signal may be from a sensor of the host computer 30 for example, an accelerometer provided in the host computer 30. For example, if the host computer 30 is a mobile device, then the device and further computer 30 have common orientation and positon information. In this case, the further signal is provided by the host processor to the device via the USB interface. Operation of automatic control will now be described with reference to Figure 4. The device is in an initial configuration, in this case the initial configuration corresponds to the orientable member having a zero angle of rotation. A downlink is formed as described above. An optical signal is sent from the access point 50 to the receiver 42 of the device 20. Signal information is extracted or determined from the received optical signal. Signal information may include one of signal strength and/or signal quality and/or signal speed. Based on the signal information, the processor may send an electronic signal to the control module instructing the control module to generate one or more control signals to a driving mechanism. In this case, the control signals instruct the driving mechanism to rotate the orientable member 24 to an orientation with a stronger signal. A stronger signal may be provided when the receiver is rotated closer to the access point. Mechanisms for feedback on signal strength and data speed feedback include known methods such as, for example, received signal strength indicators (RSSI). Polling schemes and test signals can also be implemented. Known communication protocols test signal strength.

The control module is configured to control orientation of the orientable member based on signal information including the strength of at least one signal received at the receiver or transmitted by the transmitter. Orientation may also be based on, in addition or alternatively, a control signal received from the further device or at least one additional device and/or a measurement of orientation of the orientable device and/or the further device and/or a measurement of relative orientation of the orientable device and the further device.

The driving mechanism is an internal driving mechanism for performing the rotation of the orientable member 24. The driving mechanism rotates the orientable member 24 to the rotated configuration, and the uplink 56a and downlink 58a are now shown schematically as uplink 56b and downlink 58b, respectively. In the rotated position, the signal received has a higher value of signal strength. The automatic control method may include a tracking mechanism involving the processor, the controller and the driving mechanism to maintain or find the optimum signal available when the device is in a certain position or has moved from a first position to a second position. The tracking mechanism involves continual signal testing and adjustment of orientation based on signal testing. The tracking mechanism involves measuring and/or extracting first signal information at a first orientation and then rotating the orientable member through an angular distance, typically a small angular distance, to a second orientation and receiving second signal information. The second signal information is then compared to the first signal information by the processor. If the second signal information indicates a less optimum signal, for example signal strength and/or signal speed and/or signal quality is decreased, then the processor instructs the controller to rotate the orientable member back to the first orientation. If the second signal information indicates that the second orientation provides a more optimum or improved signal, for example the signal strength and/or signal speed and/or signal quality is increased, then the processor instructs the controller to rotate the orientable member to a third orientation. Signal information is again received and compared to the second signal information. The method continues until an optimum position providing an optimum signal is found.

A change in monitored signal information may also indicate that the device and host computer are moving. A device may move between optical fields of two different access points and rotation may be necessary to move the device from the first field to the second field. An automatic tracking system may be implemented such that optimum signal strength and/or signal speed is maintained when the device is moving.

The orientable member may also be rotatable by other means, for example, by hand. To aid a user in finding the optimum signal, an indicator may be provided either on the device or via the host computer or other connected computing resource. A tracking mechanism may be implemented after an initial rotation is carried out by hand.

The indicator may be a display that shows feedback to the user about signal information to the user, for example signal strength or signal speed or signal quality. A user can operate the device to achieve an improved signal via software and/or by manual operation. The displayed feedback allows a user to determine that the optimum angle and thus optimum signal is obtained and/or to monitor the automatic positioning mechanism. The display may be on a monitor of the host computer or an LCD display on the device. In a further example, the indicator may be simple visual indicator provided on the device. A simple visual indicator may be provided by one or more lights. For example, a red light may be used to indicate that an optimum signal is not being achieved and a green light may be used to indicate that an optimum signal is being achieved. In another example, the indicator may be configured to provide an indication signal in response to signal strength being greater or equal to a threshold value.

Figure 5(a) shows a second embodiment of the optical wireless communication device 20 in an initial configuration and Figure 5(b) shows an expanded view of the second embodiment of the optical wireless communication device 20 in a rotated configuration. The second embodiment has a transceiver operable to rotate as a part within the main body of the device. In contrast to the first embodiment, the head rotates within the main body of the device.

In the second embodiment, the connector member 22 provides an opening in which the orientable member is provided. The opening is sized to permit rotation of the orientable member 24 while keeping the orientable member 24 substantially inside the opening. The opening and orientable member are sized such that in an initial configuration, the upper and lower surfaces of the orientable member are flush with the upper and lower surfaces of the connector member 22.

It is clear from description above, that various components associated with the transmitter and/or receiver can be provided on the orientable member and that various components associated with the transmitter and/or receiver can be provided on the connector member. The location of different components can be different in different embodiments and any suitable configuration or division of components between the members can be provided in different embodiments. For example, it has been mentioned above that, in various embodiments, each of OWC processor(s), analogue circuitry, digital circuitry associated with the transmitter and/or receiver may be provided on either or both the orientable member or the connector member. It has also already been mentioned that communications between the connector and the orientable member may be provided via light, via inductance or via electrical connections.

In some embodiments the transmitter may be considered to consist of one or more light emitting elements and the receiver may be considered to consist of one or more light receiving elements. The light receiving and light transmitting elements may consist of one or more optical elements, for example one or more lenses, concentrators, mirrors and/or light guides.

The light transmitting element(s) may be considered to represent the point at which light exits the device, for example for transmission through free space to a further OWC-enabled device. Similarly, the light receiving element(s) may be considered to represent the point at which light enters the device, for example following transmission through free space from the or a further OWC-enabled device. In some embodiments, the receiver is in the form of light receiving element(s) provided on the orientable member, and there is an optical connection (for example, provided by a waveguide, optical fibre or arrangement of at least one lens, mirror or concentrator) that directs light received by the receiver to photodiode(s) or other photodetector located on the connector member or other component. The photodiode(s) or other photodetector converts the received light to corresponding electrical signals. In other embodiments, the photodiode(s) or other photodetector are provided on the orientable member and there is then usually an electrical or inductive connection to send the electrical signals from the photodiode(s) or other photodetector to the connector member.

Similarly, in some embodiments, the transmitter is in the form of light transmiting element(s) provided on the orientable member, and there is an optical connection (for example, provided by a waveguide, optical fibre or arrangement of at least one lens, mirror or concentrator) that directs light generated by LED(s) or other components that convert electrical (e.g. data) signals to light, from the LED(s) or other components on the connector member to the light transmiting element(s). In other embodiments, LED(s) or other components that convert electrical (e.g. data) signals to light are provided on the orientable member and there is then usually an electrical or inductive connection to send the electrical signals from the connector member or other component to the LED(s) or other components on the orientable member for conversion to light signals at the orientable member.

The photodiode(s) or other photodetector converts the received light to corresponding electrical signals. In other embodiments, the photodiode(s) or other photodetector are provided on the orientable member and there is then usually an electrical or inductive connection to send the electrical signals from the photodiode(s) or other photodetector to the connector member.

The orientable member, connector member may be provided in various configurations in different embodiments.

Figure 6(a) shows an expanded view of a third embodiment of the optical wireless communication device 20 in an initial configuration and Figure 6(b) shows an expanded view of the third embodiment of the optical wireless communication device 20 in a rotated configuration. In the third embodiment, the connector member 22 and orientable member 24 extend along an axis defined by the connector. In contrast to the first and second embodiment, the connector member 22 is surrounded by the orientable member 24. The connector member and 22 and orientable member 24 are free to rotate relative to each other. The optical transceiver can be rotated or the USB connector can be rotated, through an angle up to 360 degrees.

While both parts are free to rotate, in use, the connector is inserted into a port of a further device and held in a fixed position. The connector member 22 is thereby held in a fixed position defining a rotation axis, about which the orientable member can rotate. The transceiver, not pictured in Figure 6(a) and Figure 6(b), is provided on the orientable member. The processing circuitry is provided in either the connector member or the orientable member.

Figure 7 shows a fourth embodiment of the optical wireless communication device 20 in an initial configuration. The fourth embodiment combines features shown in the first embodiment and the third embodiment. In further detail, the orientable member has a first portion 24a and a second portion 24b. The first portion 24a is substantially the same as the orientable member described with reference to the third embodiment. The second portion 24b is substantially the same as the orientable member described with reference to the first embodiment. The second portion 24b could also be implemented as described with reference to the second embodiment. The fourth embodiment provides an orientable member that is orientable through at least two degrees of freedom. The first portion 24a is rotatably coupled to the connector member 22 and surrounds the connector member 22 such that the first portion 24a is operable to rotate around the axis defined by the connector 26. The second portion 24b is coupled to the first portion 24a by a mechanism that is operable to switch its coupling mode. The coupling mode can be a fixed coupling mode, in which the first and second portions move together and a rotatable coupling mode, in which the first and second portions move relative to each other. This mechanism allows the device 20 to move between an initial configuration and rotated configuration, wherein the rotated configuration can be one of a collected rotated configuration and a staggered rotated configuration.

In further detail, in the fixed coupling mode, the second portion 24b and first portion 24a are fixedly coupled and are operable to rotate together about the connector axis. In the staggered coupling mode, the first portion 24a and the second portion 24b are rotatably coupled such that the first portion 24a remains fixed relative to the connector 26 and the second portion 24b is operable to rotate relative to the first portion 24a.

In operation, the device 20 is connected to a port of the further device. Starting from an initial configuration, the device 20 is in the collected coupling mode and the first and second portions are subject to a first rotation through a first angle to arrive at a collected rotated configuration. The collected rotated configuration includes the first portion 24a in a first position and the second portion 24b in a second position. Following the first rotation, the mechanism can be switched to the rotatable coupling mode, in which the second portion 24b is subject to a second rotation through a second angle and the first rotation remains fixed in the first position. Upon terminating the second rotation the device arrives in a staggered rotated configuration including the first portion 24a in the first position and the second portion 24b in a third position. In total, in moving from the initial configuration to the staggered rotated configuration, via the first rotated configuration, the second portion 24b is rotated through an angle having a value equal to the first and second angle. Switching coupling mode may be provided by a manual switch or may be controlled by control signals provided by a control module.

Figure 7 shows an embodiment, wherein the orientable member has two portions orientable members rotating about the same axis. A further embodiment has two portions rotating about two different axes. For example, the first and second portions are configured to rotate about a first axis to arrive at a first rotated configuration which is characterised by a first portion at a first position and a second portion at a second position. The second portion is configured to rotate about a second axis to arrive at a third position while the first portion remains fixed in the first position.

In embodiments, rotation of the orientable member may be implemented to be up to 360 degrees or full rotation. Rotation may be restricted to a sub-range. In embodiments comprising a first and second portion of the orientable member, both portions may be operable to rotate through 360 degrees or a sub-range of 360 degrees. For example, rotation of one portion may be used to increase angle of rotation of another. If full rotation is not implemented in either portion, a first portion may be operable to rotate through a first sub-range and the second portion may be operable to rotate through a second sub-range. These two sub-ranges may sum to allow up to 360 degree rotation or sum to allow rotation within a larger sub-range.

In further embodiments, the second sub-range may provide a refinement of the first rotation and therefore may be smaller.

The orientable member can be rotated through an angle up to 360 degrees. Alternatively, the angle of rotation may be restricted, for example, to be less than 270 degrees, less than 180 degrees or less than 90 degrees.

Any arrangement of second axis to first axis is possible. For example, the axes may be orthogonal or parallel. A further rotational portion may also be provided that rotates about a third axis, that is orthogonal or parallel to the first and/or second axis. An orientable member may is orientable through three degrees of freedom.

While the embodiments show both a transceiver and receiver provided on the orientable member, other embodiments have either a transmitter or a receiver provided on the orientable member. Further embodiments may have more than one transmitter and/or more than one receiver provided on the orientable member.

A further embodiment has a transmitter provided on a first orientable member and a receiver provided on a second orientable member. The second orientable member may be operable to be oriented relative to the first orientable member thus allowing the receiver and transmitter to be arranged with different orientation angles. The rotation of the first orientable member may be independent of the rotation of the second orientable member. Such an arrangement may compensate for distances between the access point transmitter and receiver. The first orientable member and second orientable member may each be rotatable around a respective axis or axes. In some embodiments, the first orientable member and second orientable member may be relatively orientable through three degrees of freedom.

In further embodiments, one portion of the orientable member may be configured to be rotated by hand and another portion of the orientable member may be configured to be rotated by automatic control mechanism.

A skilled person will appreciate that variations of the described embodiments are possible without departing from the invention. For example, while a simple rotational mechanical coupling member is described other joints may be used. In particular, a gimbal mechanism may be implemented to provide substantially full 360 degree movement. Accordingly, the above description of the specific embodiment is made by way of example only and not for the purposes of limitations. It will be clear to the skilled person that minor modifications may be made without significant changes to the operation described.