Patent ID: 6104447
Filing Date: 2000-08-15
Classification: G02B,G02F,G03B,G06F,H04N

Abstract:
A backlighting panel construction having first and second modes of operation, comprisinglight producing means for producing light during said first mode;a light guiding structure having first and second light guiding surfaces between which said produced light can be totally internally reflected;a light diffusing structure operably associated with said light guiding structure, having a light scattering state of operation selectable during said first mode, and a light non-scattering state of operation selectable during said second mode; andstate selection means for selecting said light scattering state of operation for said light diffusing structure during said first mode, and for selecting said light non-scattering state of operation for said light diffusing structure during said second mode,wherein during said first mode, said light diffusing structure produces scattered light as light reflected within said light guiding structure is transmitted through said light diffusing structure and said scattered light is transmitted through said first light guiding surface of said light guiding structure, andwherein during said second mode, said light diffusing structure permits light produced from an external source to be transmitted through the second and first light guiding surfaces of said light guiding structure and through said light diffusing structure without substantial scattering.