A display capable of inhibiting a transistor from an instable operation resulting from fluctuation of the potential of a shielding film and suppressing occurrence of a malfunction is provided. As a consequence, the data retrieval method is executed without external access to a DASD or other external data source and without the resulting delays or unavailabilities. An antenna element has one end and another end, where one end thereof is connected with a position in the ceiling conductor in a vicinity of opened another end of the rectangular waveguide, and another end thereof is connected with a feeding portion located in the grounding conductor.