主权项 |
1. A control panel, comprising;
a viewing element which is, in use, positioned over a display that is configurable to display an image, with at least part of the display being visible through the viewing element; at least two light controllers that are movably disposed to the viewing element, each light controller rotatable relative to the viewing element about an axis of rotation; at least two light emitters, each light emitter operable to deliver light across the viewing element to at least one of the at least two light controllers; and at least two light detectors, each light detector operable to detect light from at least one of the at least two light controllers; wherein: the at least two light emitters and the at least two light detectors are configured to form a grid of sensing paths with two or more intersecting sensing paths across the viewing element; the at least two light controllers are scanned by sequentially activating the at least two light emitters and the at least two light detectors; the light detected by the light detectors is representative of movement of the light controllers and is utilized to configure the image as displayed by the display; the light delivered across the viewing element to the at least two light controllers is transmitted in a direction across the respective at least two light controllers, the direction being substantially parallel to the plane of the viewing element; and wherein a portion of the light delivered across the viewing element to the light controller is transmitted through the light controller, and a portion of light detected by an associated light detector is transmitted across the light controller without being reflected by the light controller. |