Video signals radiation leakage from computer CRT electron beam

The electron beam in computer CRT radiates an electromagnetic field. Firstly, the radiation of a travelling electron is discussed and then the acceleration field of the electron beam, and radiated field of its equivalent electric dipole, are analyzed. It is pointed out that they both bring risk to the information security of computer. By receiving radiation from a CRT electron beam, the content of VDU screen can be reconstructed.