Enhanced LCD backlight
First Claim
1. A light guide comprising:
- a) at least one input surface and output surface wherein incident light exits the light guide when the total internal reflection condition is not satisfied; and
b) a first scattering region disposed to receive light from the input surface and direct light to the output surface, comprising a continuous phase material of refractive index nx1 and a first dispersed phase material of refractive index nx2 wherein |nx1−
nx2|>
0.001 and one or more of the first dispersed phase domains are non-spherical in shape.
7 Assignments
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Accused Products
Abstract
The present invention provides an improved light guide with inherently more flexibility for display system designers and higher optical efficiency. By using a light guide containing substantially aligned non-spherical particles, more efficient control of the light scattering can be achieved. One or more regions containing ellipsoidal particles may be used and the particle sizes may vary between 2 and 100 microns in the smaller dimension. The light scattering regions may be substantially orthogonal in their axis of alignment. Alternatively, one or more asymmetrically scattering films can be used in combination with a backlight light guide and a reflector to produce an efficient backlight system. The light guides may be manufactured by embossing, stamping, or compression molding a light guide in a suitable light guide material containing asymmetric particles substantially aligned in one direction. The light scattering light guide or non-scattering light guide may be used with one or more light sources, collimating films or symmetric or asymmetric scattering films to produce an efficient backlight that can be combined with a liquid crystal display or other transmissive display. By maintaining more control over the scattering, the efficiency of the recycling of light by using reflective polarizers can also be increased.
187 Citations
26 Claims
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1. A light guide comprising:
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a) at least one input surface and output surface wherein incident light exits the light guide when the total internal reflection condition is not satisfied; and
b) a first scattering region disposed to receive light from the input surface and direct light to the output surface, comprising a continuous phase material of refractive index nx1 and a first dispersed phase material of refractive index nx2 wherein |nx1−
nx2|>
0.001 and one or more of the first dispersed phase domains are non-spherical in shape. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26)
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Specification