The disclosure provides a reading device (2, 20) adapted to read-out infrared readable data (D, D10) provided by a covered part (1.1.1.2, 10.1.1.2) of a movable component (1.1, 10.1) of a drug delivery device (1, 10), wherein the reading device (2, 20) comprises—at least one electromagnetic radiation source (2.2, 20.2) configured to emit infrared radiation and adapted to illuminate the infrared readable data (D, D10) on the covered part (1.1.1.2, 10.1.1.2),—at least one optical sensor unit (2.3, 20.3) configured to detect infrared radiation reflected from the covered part (1.1.1.2, 10.1.1.2) of the movable component (1.1, 10.1) and—at least one processing unit (2.4, 20.4) configured to determine a data value of the infrared readable data (D, D10) as a function of the detected reflected infrared radiation. The disclosure further provides a drug delivery device (1, 10) and a drug delivery device (1, 10) in combination with the reading device (2, 20).
