| 摘要 |
<p>In an information retrieval and display system, an interface unit (32) receives signals from a hand-held user control unit (34), for example joystick (38), and controls the information displayed on a display (30) in response thereto. Each control signal from the hand-held unit (34) is generated by a single operator action, that is, movement of the joystick (38) in a given direction. The information available for display is arranged in a tree structure. The interface unit (32) is arranged to scroll through the currently displayed information in a first direction at a speed related to the displacement of the joystick (38) in a first (up) direction, to scroll through the currently displayed information in the opposite direction at a speed related to the displacement of the joystick (38) in a second, opposite (down) direction, to display information from a lower level in the tree in response to movement of the joystick in the third (right) direction, and to display information from a higher level in the tree in response to movement of the joystick in a fourth (left) direction.</p> |
