Light-guide lights suitable for use in illuminated displays
First Claim
1. A light-guide device comprising a housing defining a light-guiding optical cavity having first and second generally parallel major faces, and at least one light source arranged to direct visible light into the cavity from one side, to he guided between the first and second major faces, wherein;
- (a) the first major face comprises a material having coefficients of reflection and transmission that vary with the angle at which light is incident on the material; and
(b) the second major race comprises a narrow-scattering reflective material having a total reflectance of at least 85% for visible light incident on the surface at any angle;
whereby light frown within the cavity is emitted substantially uniformly across the first major surface.
1 Assignment
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Accused Products
Abstract
A light-guide light (1) suitable for use in illuminated displays and signs comprises a housing (3) defining an optical cavity having first and second generally parallel major faces (5, 6), and a light source (11) positioned to direct light into the optical cavity from one side. The first major face (5) comprises a material (for example, a prismatic film) having coefficients of reflection and transmission that vary with the angle at which light is incident on the material. The second major face (6) comprises a narrow-scattering reflective material having a reflectance of at least 85%, for example a highly-efficient reflective material provided with a suitable textured pattern.
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Citations
12 Claims
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1. A light-guide device comprising a housing defining a light-guiding optical cavity having first and second generally parallel major faces, and at least one light source arranged to direct visible light into the cavity from one side, to he guided between the first and second major faces, wherein;
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(a) the first major face comprises a material having coefficients of reflection and transmission that vary with the angle at which light is incident on the material; and (b) the second major race comprises a narrow-scattering reflective material having a total reflectance of at least 85% for visible light incident on the surface at any angle; whereby light frown within the cavity is emitted substantially uniformly across the first major surface. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
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Specification