| 摘要 |
A security thread (1) for a bank note comprises a discontinuous magnetic thread (3) which has binary coding, the binary values being denoted by the presence or absence of bit lengths of thread. The coding employed is repetitive, comprising alternating termination segments (4) and word segments (5). The length of a termination segment in terms of bit lengths is less than the length of a word but is greater than the maximum length permitted within a word of bits which have the same binary value as the bits in a termination segment. The invention provides resistance to false readings and, by varying the parameters of bit length, word length, length of the termination segment and otherwise, a multiplicity of different codings having the same general format. |
