The present invention relates to improvements in or relating to mobile telecommunications.

With the development of third generation mobile telephones or terminals, referred to hereinafter as mobile units, there is likely to be a rapid growth in the different application and uses of such mobiles. Third generation mobile units will have sufficient bandwidth to transmit video and to allow access to the Internet. However, one potential problem is how to display the images and provide the human interface when accessing the Internet, for example.

It is therefore an object of the present invention to provide a mobile telecommunications system which includes means for displaying images.

It is another object of the present invention to provide means for interacting with such images when accessing the Internet.

In accordance with one aspect of the present invention, there is provided a mobile telecommunications system comprising :- a mobile unit; projector means for providing images on a surface; and means for providing interaction with said images.

Advantageously, said projector means projects a virtual image onto said surface. Said means for providing interaction with said images comprises camera means having a field of view substantially the same as said virtual image. Said means for providing interaction with said images further comprises pointer means movable within said virtual image and detectable by said camera means.

In a preferred embodiment of the present invention, said camera means is built into said mobile unit. Said projector means may also be built into said mobile unit.

In another embodiment of the present invention, said projector means comprises a liquid crystal display, said surface being the surface of said liquid crystal display. It is preferred that said liquid crystal display is pressure sensitive.

In a further embodiment of the present invention, cradle means is provided for connecting with said mobile unit. Said projector means may be mounted in said cradle means. Said means for providing interaction with said images may also mounted in said cradle means.

For a better understanding of the present invention, reference will now be made, by way of example only, to the accompanying drawings, in which:- Figure 1 illustrates an embodiment of the present invention; and Figure 2 is a block diagram of a mobile unit in accordance with the present invention.

The term'mobile unit', as discussed above, is intended to encompass both mobile telephones or terminals, as well as other similar telecommunications devices.

In Figure 1, a mobile unit 10 is shown which includes a projector and camera unit, shown schematically as 12. However, although the projector and camera unit 12 is shown as a single device, it will be appreciated that the projector and the camera may be separate devices within the mobile unit 10.

The projector and camera unit 12 is built into the mobile 10, and operates both to project the main display of the mobile unit onto a surface 14 as a virtual display 16 and to allow the selection of icons (not shown) forming

part of the virtual display 16 by detecting the position of a pointer 18 within the virtual display 16.

The surface 14 may be substantially horizontal and may comprise a sheet of paper onto which the virtual display 16 is projected. The pointer 18 can be moved by a user 20 within the virtual display 16 to select the icons.

Figure 2 illustrates a block diagram of a mobile unit 10 in accordance with the present invention. The mobile unit 10 include an antenna 100 for receiving and transmitting signals to a base station (not shown). The antenna 100 is connected to a digital signal processing (DSP) unit 102 which processes the received signal and prepares a signal for transmission, that is, carries out any processing associated with the telecommunications network to which the mobile unit 10 is connected. It will be appreciated that the telecommunications network may comprise a conventional mobile telecommunications network or a network through which the Internet can be accessed. In either case, suitable protocols are employed to enable appropriate of the signals both after reception and prior to transmission.

A buffer 104 is connected to the DSP unit 102 via a bi-directional link 106, the buffer storing data from the DSP unit 102. The DSP unit 102 is also connected to a communications bus 108 via a bi-directional link 110.

Also connected to the bus 108 via a bi-directional link 110 is a processor unit 112. Processor unit 112 carries out processing associated with image processing as will be described in more detail later. Processor unit 112 is also connected to a read-only memory (ROM) 116 and a random access memory (RAM) 118 via respective bi-directional links 120 and 122. The ROM 116 and the RAM 118 are also connected directly to the bus 108 via respective bi-directional links 124 and 126 respectively. The ROM 116 stores programs for access by the processor 114. The RAM 118 provides a memory for the processor unit 114.

Also connected to the bus 108 via respective links 128,130,132 and 134 are projector unit 136, camera unit 138, microphone unit 140 and speaker unit 142. Links 128,130,132 and 134 are uni-directional links, links 128 and 134 allowing control signals on the bus 108 to be fed to the projector unit 136 and speaker unit 142 respectively and links 130,132 allowing signals to be fed from the camera unit 138 and microphone unit 140 respectively to the bus 108.

The projector unit 136, camera unit 138, microphone unit 140 and speaker unit 142 can be controlled by the processor unit 114 or the DSP unit 102 via the appropriate bi-directional link and the bus 108.

The projector unit 136 produces the virtual display 16 as shown in Figure 1 under the control of the processor unit 114. The image signal which is to be projected as the virtual display 16 is received by the antenna 100, processed by the DSP unit 102 and the processor unit 114 before being sent to the projector unit 136 for display.

The camera unit 138 effectively has the same field of view as the virtual display 16 so that the location of the pointer 18 can be determined.

When the pointer 18 is detected within the field of view of the camera unit 138, the camera unit 138 provides a signal for the processor unit 114 which indicates the position of the pointer 18 and is converted into a signal for the DSP unit 102 for transmission via antenna 100 back to the network to which the mobile unit 10 is connected. As discussed above, the DSP unit 102 will process the signals in accordance with the appropriate protocol for that particular transmission.

The microphone unit 140 and speaker unit 142 comprise components which are currently employed in conventional mobile units. For normal voice transmissions only, signals received at the antenna 100 are processed by the DSP unit 102 and fed to the speaker unit 142 via link 110, bus 108 and

link 134 so that a user can hear the voice transmission. Similarly, the microphone unit 140 receives voice from the user and converts it to signals for the DSP unit 102 prior to transmission through the antenna to the network, the signals passing from the microphone unit 140 to the DSP unit 102 via link 132, bus 108 and link 110.

As shown in Figure 1, it is possible to stand the mobile unit 10 substantially upright so that the projector unit 136 can project the virtual display 16 onto surface 14. If the mobile unit 10 is connected to an Internet site via an Internet server, the DSP unit 102 processes the received signal to provide video signals for the processor unit 114 and audio signals for the speaker unit 142. The processor unit 114 processes the video signals and provides a signal for the projector unit 136 which is eventually projected onto surface 14 as the virtual display 16.

In accordance with the present invention, the projector unit 136 projects a virtual display 16 onto surface 14 which may simply be a sheet of white paper positioned in front of the mobile unit 10. As discussed above, pointer 18 is used to select icons in the virtual display 16 and the camera unit 138 determines the position of the pointer 18 with respect to the virtual display 16 to provide a signal for the DSP unit 102 for transmission via antenna 100 to the Internet server. The user 20 controls the pages/display by using the pointer 18 in a similar fashion to a touch sensitive screen, but in this case, the location of the pointer 18 is detected by the camera unit 138.

It will readily be appreciated that it may be possible to vary the angle of the projector unit 136 so that the virtual display 16 can be projected surfaces at angles other than substantially horizontal, for example, onto a wall for the purposes of presentations etc.

As shown in Figure 1, the mobile unit 10 is substantially upright to allow the projector and camera unit 12 to operate effectively. The mobile

unit 10 may have a stand or other means (not shown) which allows it to be positioned substantially upright.

However, it will be appreciated that it may not be practical in some instances for the mobile unit 10 to include the projector and camera unit 12 as described above with reference to Figures 1 and 2. In these cases, the mobile unit 10 could be mounted within a cradle (not shown) which houses the projector unit and the camera unit, the mobile unit 10 being connected to the projector unit and the camera unit by a suitable interface. Such a cradle could also include a separate speaker unit to amplify received audio signals.

In another embodiment of the present invention, the cradle may also include a liquid crystal display (LCD) screen attached to it to provide both the virtual display and a touch sensitive screen. In this case, the projector and camera unit would not be necessary. The LCD screen may form an integral part of the cradle or it may be connected thereto by a suitable link.

In the latter case, the LCD screen may be remote from the mobile unit, for example, mounted on a wall.

Although the present invention has been described with reference to mobile telephones or terminals, it will readily be appreciated that the invention can also be used in any situation where there is a requirement for a virtual screen.