Information display system having a multiple cell raster scan display

An information display system capable of displaying a variable mosaic of information derived from a number of separate information items, comprising a raster scan display having a display screen, said display screen being divided into a number of cells, each cell representing a separate area of the display screen and each cell having an unique screen address;

• an information store comprising a plurality of storage elements and having a storage capacity for display information greater than the maximum amount of information which may be displayed on the screen at any instant and capable of storing a number of separate information items;
• display control means for generating the screen addresses of successive cells of the display screen;
• mapping means including a look-up table in the form of a random access memory containing the address of each individual storage element in the information store and responsive to the screen addresses for translating each individual screen address individually into a store address indicating the location in the information store of the information to be displayed in the cell of the display screen corresponding to the individual screen address such that each separate cell of the display may display information from any selected information item;
• display logic means responsive to the outputs from each successive location in the information store and operatively connected to the display to produce the necessary signals for activating the display;
• and map changing means connected to the mapping means for varying the translations effected by the mapping means on any desired screen address by changing the contents of said look-up table.