BACKGROUND

The present disclosure relates generally to light emitting diode (LED) lighting systems, and more specifically, to systems, methods, and assemblies regarding optical structures for LED lighting systems.

Some known light systems use LEDs as a light source. LEDs can provide instant illumination with no warm-up required. LEDs are also shock and vibration resistant. Additionally, LEDs can increase energy savings. Some applications for LED-based light systems include hazardous environments where electrical and thermal abnormalities are to be avoided to prevent explosion or other fire hazards.

Some known LED light system designs include a polycarbonate plate with individual bubble domes that surrounds and virtually encapsulates the LED itself. The domes can bend the light generated by the LEDs to a required or desired distribution pattern. These domes, however, are often positioned very close to the LED and may result in thermal and/or radiometric power incident on the optic plate, which is undesirable.

SUMMARY

Aspects of the present disclosure relate to a light system including: a substrate; one or more LEDs coupled to the substrate; and an optical distribution plate positioned proximate the substrate, the optical distribution plate including one or more optical structures each corresponding to the one or more LEDs, wherein the one or more optical structures include: a first surface that focuses LED light from the corresponding LED in a first orientation; and an opposite second surface that distributes LED light from the LED in a second orientation, wherein the second orientation is substantially orthogonal to the first orientation.

In an example, the second surface includes at least one total internal reflection (TIR) element and at least one refractive element. In another example, a centerline plane extending along the first orientation is defined on the second surface, and the at least one TIR element and the at least one refractive element are positioned symmetrically about the centerline plane. In yet another example, the at least one TIR element reflects LED light substantially away from, or across, the centerline plane, and the at least one refractive element refracts LED light substantially away from the centerline plane. In still another example, the optical distribution plate forms an Illuminating Engineering Society of North America (IESNA) type I beam pattern. In an example, the first surface includes a Fresnel element.

In another example, the optical distribution plate forms an Illuminating Engineering Society of North America (IESNA) type III beam pattern. In yet another example, a centerline plane extending along the second orientation is defined on the first surface, and the first surface focuses LED light towards one side of the centerline plane. In still another example, the first surface includes at least one total internal reflection (TIR) element and at least one refractive element. In an example, the first surface is disposed adjacent to and spaced away from the corresponding LED. In another example, a reflector plate is disposed between the substrate and the optical distribution plate.

In another aspect, the technology relates to an optical structure for a LED including: an inner surface positionable adjacent to the LED that focuses LED light emitted from the LED in a first direction; and an opposite outer surface that distributes LED light emitted from the LED in a second direction, wherein the second direction is substantially orthogonal to the first direction, and wherein the outer surface includes a plurality of total internal reflection (TIR) elements and a plurality of refractive elements.

In an example, a centerline plane extending along the first direction is defined on the outer surface, and a set of single TIR elements are positioned symmetrically adjacent the centerline plane and each single TIR element reflects LED light substantially away from the centerline plane. In another example, wherein a set of refractive elements are positioned symmetrically about the centerline plane and outside of the set of single TIR elements, and each refractive element of the set of refractive elements refracts LED light substantially away from the centerline plane. In yet another example, a set of double TIR elements are positioned symmetrically about the centerline plane and outside of the set of refractive elements, and each double TIR element reflects LED light substantially away from and across the centerline plane. In still another example, the set of refractive elements is a first set of refractive elements and a second set of refractive elements are positioned symmetrically about the centerline plane and outside of the set of double TIR elements, and each refractive element of the second set of refractive elements refracts LED light substantially away from the centerline plane. In an example, the inner surface includes a Fresnel element. In another example, the inner surface includes at least one TIR element and at least one refractive element, wherein a centerline plane extending along the second direction is defined on the inner surface, and the at least one TIR element is offset from the centerline plane and reflects LED light substantially towards the centerline plane.

In another aspect, the technology relates to a method of manufacturing an optical structure for a LED including: forming a first surface of the optical structure that focuses LED light emitted from the LED in a first orientation; and forming a second surface of the optical structure that distributes LED light emitted from the LED in a second orientation, wherein the second orientation is substantially orthogonal to the first orientation, and wherein forming the second surface includes: defining a plurality of total internal reflection (TIR) elements on the second surface; and defining a plurality of refractive elements on the second surface, wherein the plurality of TIR elements and the plurality of refractive elements are arranged symmetrically about a centerline plane extending along the first orientation defined on the outer surface.

In an example, forming the first surface includes: defining at least one TIR element on the first surface, wherein the at least one TIR element is offset from a centerline plane extending along the second orientation defined on the first surface; and defining at least one refractive element on the first surface.

A variety of additional inventive aspects will be set forth in the description that follows. The inventive aspects can relate to individual features and to combinations of features. It is to be understood that both the forgoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the broad inventive concepts upon which the examples disclosed herein are based.

