Illumination device for simulation of neon lighting
View Patent ↗An illumination device for simulating neon lighting comprising a plurality of spaced point light sources positioned adjacent a lateral light receiving surface of a substantially rod-like waveguide made of a material that preferentially scatters light entering the light receiving surface such that the light intensity pattern exiting a lateral light emitting surface of the waveguide has a substantially uniform light intensity pattern.
1. An illumination device for simulating neon lighting, comprising:
an essentially solid, leaky waveguide rod having a predetermined length with a lateral light receiving surface and a lateral light emitting surface;
an elongated light source extending substantially along said predetermined length of and positioned adjacent to said light receiving surface for emitting a portion of light emitted by said light source directly into said light receiving surface; and
a housing positioned externally and adjacent to said waveguide rod and defining a volume that encompasses said elongated light source, whereby said housing includes side walls having internally light reflecting surfaces and serves to collect and direct light emitted by said light source into said lateral light receiving surface such that light is preferentially directed along the predetermined length of the leaky waveguide rod, exiting said light emitting surface in an elongated light intensity pattern that has a major axis extending along the length of said waveguide rod.
2. The illumination device of claim 1 , and further including transparent material filling at least a portion of said volume and abutting said light receiving surface and said elongated light source, said transparent material having an index of refraction that reduces Fresnel losses between said light source and said waveguide.
3. The illumination device of claim 2 , in which said elongated light source is a multiplicity of point light sources.
4. The illumination device of claim 3 , in which said point light sources are light emitting diodes.
5. The illumination device of claim 4 , in which the index of refraction of said transparent material is essentially the same as that of said waveguide rod and housings of said light emitting diodes.
6. The illumination device of claim 4 , in which said light emitting diodes are positioned a distance from said light emitting surface sufficient to allow a light intensity pattern from each of said point light sources to overlap neighboring light intensity patterns so that the light intensity pattern collectively emitted from said light emitting surface appears uniform.
7. The light illumination device of claim 1 , in which said waveguide rod is comprised of an acrylic with light scattering characteristics.
8. The illumination device of claim 1 , in which said side walls have externally light absorbing surfaces.