| 摘要 |
PURPOSE:To sufficiently raise a secret keeping effect of secret information, by storing in addition additional information which is necessary for keeping a secret, and displaying or printing it by making it overlap. CONSTITUTION:When a display data of a display data storage device 3 is read out, it is provided to a display tube 5 through an OR gate 4. On the other hand, a display data of a storage device 9 is also read out, but its display data is provided to the OR gate 4 through an AND gate 8, and is provided to the display tube 5 together with the display data of the storage device 3. In this state, when a store data is moved, a desired part of document information can be displayed on the display tube 5. In this case, too, a display position of additional information is not moved. Subsequently, when an output of the OR gate 4 is provided to a printing device 6 in order to print display on the display tube 5, printed matter which adds the additional information to the document information is obtained. |
