Patent ID: 6791636
Filing Date: 2004-09-14
Classification: G02B,G02F

Abstract:
A device comprising:a backlight for a color liquid crystal display, said backlight comprising: at least one light guide having a first surface, an opposing second surface, and a plurality of edges; at least one red light emitting diode (LED) optically coupled to a first edge of said light guide; at least one green LED optically coupled to a second edge of said light guide; and at least one blue LED optically coupled to a third edge of said light guide, said light guide including light directing elements, a first set of light directing elements causing light entering said first edge to be directed to exit said first surface in areas corresponding to red pixels in said display, second set of light directing elements causing light entering said second edge to be directed to exit said first surface in areas corresponding to green pixels in said display, and a third set of light directing elements causing light entering said third edge to be directed to exit said first surface in areas corresponding to blue pixels in said display wherein, said first of light directing elements include ridges having angled surfaces for receiving light entering said first edge; said second set of light directing elements including ridges having angled surfaces orthogonal to said angled surfaces of said first set of light directing elements surfaces for receiving light entering said second edge; and said third set of light directing elements includes ridges having angled surfaces orthogonal to said angled surfaces of said first set and said second set of light directing elements surfaces for receiving light entering said third edge.