In a transparent and spread illuminating apparatus 1, a light reflection pattern 7 consisting of the concave and convex is formed on the front surface 6 of a transparent substrate 2 so that the emission light is allowed to be uniformly irradiated on the face of the transparent substrate 2 regardless...http://www.google.com.au/patents/US6295104?utm_source=gb-gplus-sharePatent US6295104 - Front illuminating system with layer between light guide and LCD
