User interface with acoustic proximity and position sensing arrangements

A method of detecting a user input to a device, the method comprising:

• providing a display on a surface;
• using an acoustic proximity sensing arrangement to produce out-of-plane touch information relating to whether an input object is within a threshold distance of the surface in a z-direction;
• using an acoustic position sensing arrangement to produce in-plane position information relating to a position of the input object on the surface in an x-direction and a y-direction;
• and
• determining an input to the device from the in-plane position information only when it is determined from the out-of-plane touch information that the input object is within the threshold distance of the surface,
• wherein the acoustic position sensing arrangement is operated in a first mode if the processing arrangement determines from the touch information that the input object is within the threshold distance of the surface but is operated in a second mode if the processing arrangement does not determine from the touch information that the input object is within the threshold distance of the surface, wherein the acoustic position sensing arrangement remains enabled in the second mode, wherein the second mode consumes less power than the first mode.

A system for detecting a user input to a device, the system comprising:

• a display arrangement arranged to provide a display on a surface;
• an acoustic proximity sensing arrangement configured to produce out-of-plane touch information relating to whether an input object is within a threshold distance of the surface in a z-direction;
• an acoustic position sensing arrangement configured to produce in-plane position information relating to a position of the input object on the surface in an x-direction and a y-direction;
• and
• a processing arrangement configured to determine an input to the device from the in-plane position information only when the processing arrangement determines from the out-of-plane touch information that the input object is within the threshold distance of the surface,
• wherein the acoustic proximity sensing arrangement is arranged to determine whether a user is within a second threshold distance of the surface, wherein the acoustic proximity sensing arrangement is arranged to disable the display arrangement unless a user is detected within the second threshold distance, wherein the second threshold distance is greater than the threshold distance.

A method of detecting a user input to a device, the method comprising:

• providing a display on a surface;
• using an acoustic proximity sensing arrangement to produce out-of-plane touch information relating to whether an input object is within a threshold distance of the surface in a z-direction;
• using an acoustic position sensing arrangement to produce in-plane position information relating to a position of the input object on the surface in an x-direction and a y-direction;
• determining an input to the device from the in-plane position information only when it is determined from the out-of-plane touch information that the input object is within the threshold distance of the surface;
• and
• using the acoustic proximity sensing arrangement to determine whether a user is within a second threshold distance of the surface, wherein the acoustic proximity sensing arrangement is arranged to disable the display arrangement unless a user is detected within the second threshold distance, wherein the second threshold distance is greater than the threshold distance.