Information as to a direction(s) to be followed to avoid a hazard is unambiguously transmitted by energizing lamps of an array in accordance with stored data whereby unique sequential flash patterns are generated. A selectable pattern includes a long initial flash followed by a plurality of relatively...http://www.google.fr/patents/US5157382?utm_source=gb-gplus-shareBrevet US5157382 - Directional information conveying method and apparatus
Directional information conveying method and apparatus
