Cathode structure for cathode ray tube comprising an eyelet in two separate parts positioned such that one of the parts covers, in the longitudinal direction and at least partially, the second part. Dynamically rendered web pages are provided with a special script therein. The transmitting unit 263 connects the electrode 271 and the electrode 272 to an amplifying unit under control of the electrode controlling unit 261, and transmits a signal to a communication medium 280 via one of the electrodes.