Control for a communication device

#This invention relates to controls, such as rotary controls, for use on communication devices.

#Communication devices, such as portable and mobile radios, often include rotary controls for volume adjustment, channel changing and the like. When designing communication devices having rotary controls, the designer is challenged by the fact that the controls can be difficult to seal and are expensive, particularly those controls having concentric and dual (push/rotate) functionality. FIG. 1 is a cross-sectional view of a prior art high profile rotary control 100.

#For products requiring front-face navigational control, a substantial “z-height” 102 is required. In these types of products, a shaft 104 typically protrudes through the radio housing 106 thus requiring a seal 108. FIG. 2 provides examples of portable and mobile communication devices 202, 204 incorporating prior art high profile controls 206.

#The features of the present invention, which are believed to be novel, are set forth with particularity in the appended claims. The invention, together with further objects and advantages thereof, may best be understood by reference to the following description, taken in conjunction with the accompanying drawings, in the several figures of which like reference numerals identify like elements, and in which:

#FIG. 1 is a cross-sectional view of a prior art high profile rotary control;

#FIG. 2 is an example of portable and mobile communication devices incorporating prior art high profile controls;

#While the specification concludes with claims defining the features of the invention that are regarded as novel, it is believed that the invention will be better understood from a consideration of the following description in conjunction with the drawing figures, in which like reference numerals are carried forward.

#In accordance with the present invention, there is provided herein a control incorporating optical tracking technology to facilitate selecting communication device parameters. Unlike other optical encoder based rotary switches, the control formed in accordance with the present invention does not count light-interruptions but is instead based on digital signal processor detection of surface movement (both rotational and/or axial) of a rotary control. The control formed in accordance with the present invention also eliminates the need for independent sealing of the control.

#Optical tracking technology is available in the form of integrated circuitry in conjunction with a light emitting diode (LED) that lights up a surface. This technology is found in optical mice used throughout the computer industry. As a computer mouse is moved along the surface, multiple snap-shots of the surface are taken. A digital signal processor analyzes the difference between each successive snap-shot to determine in which direction and how fast the mouse has moved. In accordance with the present invention, optical tracking technology is incorporated into a control to enhance single mode (rotate) and dual mode (push/rotate) functionality and scrollability in a variety of communication devices as well as the ability to independently seal the control. The control of the present invention replaces traditional internal multi-contact rotaries with light sensitive motion detection circuitry to detect the movement of a control surface through a light permeable portion of communication device housing. Both rotational and axial movement of the control can be detected.