The optical scanning head for scanning one- and two-dimensional bar codes includes at least one combination of light emitting diodes arranged so the LEDs emit light at different angles to create a fan of light. The combination and arrangement of the LEDs depends on whether one- or two-dimensional bar...http://www.google.fr/patents/US5354977?utm_source=gb-gplus-shareBrevet US5354977 - Optical scanning head
