A personal display apparatus includes a dual-use plate,a detector, and electronic circuitry. The dual-use plate isconfigured to be worn by a user while the user is viewing ascene, to block, at least partially, X-ray radiation frompassing through the plate and reaching an eye of the user,and to display information to be viewed by the user overlaidon the scene. The detector is coupled to the plate and isconfigured to measure a level of the X-ray radiation. Theelectronic circuitry is connected to the plate and to thedetector, and is configured to exchange display signals withthe plate so as to display the information, and to send acontrol signal indicative of the level of the X-rayradiation measured by the detector.
