A controller arrangement for an optical sensing pen having a nib, the controller arrangement configured to operatively sense location data by sensing location tags on a page of printed media, and to calculate a nib-to-tag distance indicative of the location data. The controller arrangement includes an infrared (IR) illumination LED and image sensor assembly configured to transmit IR light onto, and receive IR light reflected from, respectively, the page of printed media. The arrangement also includes a force sensing infrared LED and photodiode assembly configured to detect when the nib contacts the page so that the sensor assembly is only activated when the nib is in contact with said page. The arrangement further has an infrared data association (IrDA) interface for short-range communication with a computing system, and a processor arranged in signal communication with, and configured to control, the sensor assembly, the photodiode assembly, and IrDA interface to operatively calculate the nib-to-tag distance and to transmit related location data to the computing system.