One embodiment of the present disclosure is directed to a mobile X-ray unit. The mobile X-ray unit may include a base having a control unit and a power supply. The mobile X-ray unit may further include an articulated arm associated with the base. The articulated arm may be coupled to an X-ray applicator having an X-ray tube. The X-ray tube may include a target for generating an X-ray beam, a collimator for shaping the X-ray beam, and an exit surface through which the X-ray beam is configured to exit the X-ray tube. The mobile X-ray unit may have at least one light source configured to illuminate at least a portion of the X-ray beam emitted from the exit surface.
