A highly efficient, luminous and energy-saving panel-form illuminating system suitable for mass-production, comprising at least a photoconductor, a linear light source at one side of the photoconductor, and a reflector; wherein grooves or protrusions are formed on the bottom surface of the photocond...http://www.google.de/patents/US6068382?utm_source=gb-gplus-sharePatent US6068382 - Panel-form illuminating system
