1. An electronic device, comprising: an optical trackpad module that is configured to generate a navigation signal, the optical trackpad module comprising: a light source that emits light; a trackpad that is optically coupled to the light source, the trackpad being configured to detect an input object; and a sensor array that receives at least a portion of the light emitted from the light source that is reflected off the input object, the sensor array being divided into sub-sections, each sub-section corresponding to a portion of the trackpad, each sub-section detecting at least translational movements of the input object on the corresponding trackpad portions to enable detection of rotational motion of the input object on or above the trackpad: and a processing unit that receives the navigation signal, the processing unit being operable to determine a direction of the rotational motion of the input object based on the detected translational movements of the input object on the corresponding trackpad portions, the translational movements of the input object having directions that are opposite to one another.