Display zoom controlled by proximity detection

1. A user device comprising:

a touch screen display having a touch screen input, wherein the user device comprises a front side and a rear side of a single surface area, and wherein the touch screen display is located on the front side of the single surface area;

a proximity detector arrangement located on the rear side of the single surface area, and wherein the proximity detector arrangement comprises a plurality of sensors for detecting a location of an input device by:

detecting a capacitance change due to a distance change between the input device and the rear side of the user device; and

producing a voltage change based on the detected capacitance change, the voltage change being linearly related to the distance change;

a control unit comprising a processor, the control unit being configured to:

receive data from the proximity detector to determine the location of the input device, including a value related to the distance from the input device to the rear side of the user device, the value comprising the voltage change; and

control the display to perform a zoom function to enlarge or reduce the size of content on a portion of the display based on the value related to the distance from the input device to the display so that the size of content on the screen is enlarged from an initial size as the input device moves closer to the display and maintained as the enlarged size as the input device subsequently moves further from the display, the control unit being further configured to resize the content to the initial size in response to a further input on the user device;

wherein the proximity detector arrangement and control unit are configured to detect the location of the input device within a detection volume and to provide a gradual variation in enlargement or reduction of the size of content as the distance from the input device to the rear side of the user device varies.

2. A user device according to claim 1 wherein the control unit is configured to wait for a predetermined time period between detecting a change in position of the input device within the detection volume and performing the zoom function.

3. A user device according to claim 2 wherein the control unit is configured to calculate an average coordinate position of the input device during the predetermined time period, the processor being further configured to ignore movements of the input device within a predetermined distance of the calculated average coordinate position such that they have no effect on the zoom function.

4. A user device according to claim 1 , wherein the control unit is configured to wait for a predetermined time period between detecting the entrance of the input device into the detection volume and performing the zoom function.

5. A user device according to claim 4 wherein the detection volume extends a predetermined first distance from the display and wherein the detection volume excludes a volume extending a second predetermined distance from the display, the first distance being greater than the second distance.

6. A user device according to claim 5 wherein the control unit is configured to ignore any measurements performed within the excluded volume.

7. A user device according to claim 6 wherein the touch screen input and the proximity detector arrangement are the same components.

8. A user device according to claim 1 wherein the control unit is configured to detect when the input device exits and re-enters the detection volume such that a re-entry of the input device into the detection volume causes further zooming whereby the level of zoom further increases as the input device moves closer to the display.

9. A user device according to claim 1 wherein the further input is re-entry of the input device into the detection volume for a predetermined period of time.

10. A user device according to claim 9 wherein the control unit is configured to commence detection of the distance of the input device at a first predetermined distance and to stop detection of the distance of the input device at a second predetermined distance, the first distance being different to the second distance.

11. A user device according to claim 10 wherein the plurality of sensors of the proximity detector arrangement are capacitive sensors.

12. A user device according to claim 11 wherein the user device is a mobile phone, set top box, television, laptop, computer or tablet computer.

13. A method executable by a user device for controlling a zoom function, the user device comprising a touch screen display having a touch screen input and a proximity detector arrangement comprising a plurality of sensors for detecting a location of an input device, the method comprising:

detecting a capacitance change at the proximity detector arrangement due to a distance change between the input device and a rear side of the user device, wherein the user device comprises a front side and the rear side of a single surface area, wherein the touch screen display is located on the front side of the single surface area, and wherein the proximity detector arrangement is located on the rear side of the single surface area;

producing a voltage change based on the detected capacitance change, the voltage change corresponding to the distance change;

determining the location of the input device within a detection volume based on the voltage change; and

controlling the display to perform a zoom function to enlarge or reduce the size of content on a portion of the display based on the voltage change by gradually varying the enlargement or reduction of the size of content as the distance from the input device to the rear side of the user device varies so that the size of content on the screen is enlarged from an initial size as the input device moves closer to the rear side of the user device and maintained as the enlarged size as the input device subsequently moves further from the rear side of the user device, the control unit being further configured to resize the content to the initial size in response to a further input on the user device.

14. A method according to claim 13 further comprising waiting for a predetermined time period between detecting a change in position of the input device within the detection volume and controlling the display to perform the zoom function.

15. A method according to claim 14 further comprising calculating an average coordinate position of the input device during the predetermined time period, the processor being further configured to ignore movements of the input device within a predetermined distance of the calculated average coordinate position so that such movements have no effect on the zoom function.

16. The method according to claim 13 further comprising detecting when the input device exits and re-enters the detection volume such that a re-entry of the input device into the detection volume causes further zooming whereby the level of zoom further increases as the input device moves closer to the display.