Billboard and lighting assembly with heat sink and three-part lens

An apparatus comprising a lighting assembly for illumination of an area, the lighting assembly comprising:

• a substantially planar substrate;
• a plurality of light emitting diodes (LEDs) arranged in a plurality of rows on a first surface of the substrate, wherein the LEDs are arranged in only two rows, the rows extending along a longitudinal axis in a plane of the first surface of the substrate;
• a plurality of optical elements attached to the substrate by threaded fasteners, wherein each optical element of the plurality of optical elements is separate from other optical elements of the plurality of optical elements, and wherein each optical element of the plurality of optical elements is proximate an associated LED of the plurality of LEDs such that each optical element overlies a single LED and each LED underlies a single optical element, wherein each optical element includes a first part, a second part and a third part, wherein the first part comprises a first curved surface, wherein the second part comprises a second curved surface that intersects with the first curved surface at a region between the first part and the second part, wherein the first part and the second part each have a peak relative to the substrate, the peak being spaced from the region between the first part and the second part, and wherein the third part extends beyond the region between the first part and the second part in a direction away from the associated LED;
• a heat sink thermally coupled to a second surface of the substrate, the second surface opposite the first surface, the heat sink comprising a first section substantially parallel to the substrate so that each and every LED is separated from the heat sink by the substrate, the heat sink further comprising a plurality of fins extending away from the first section and substantially perpendicular thereto, each fin extending along an axis in the plane of the first surface of the substrate, the axis for each fin being substantially perpendicular to the longitudinal axis of the first surface of the substrate, and wherein the first section of the heat sink includes a portion that extends past the substrate in a direction away from the fins;
• and
• a power supply that is separated from the substrate.

A billboard comprising:

• a support structure;
• a display surface mounted on the support structure;
• and
• a lighting assembly located so as to be able to illuminate a portion of the display surface during operation, wherein the lighting assembly comprises:
• a substantially planar substrate;
• a plurality of light emitting diodes (LEDs) arranged in a plurality of rows on a first surface of the substrate;
• a plurality of optical elements, wherein each optical element of the plurality of optical elements is proximate an associated LED of the plurality of LEDs such that each optical element overlies a single LED and each LED underlies a single optical element, wherein each optical element includes a first part, a second part and a third part, wherein the first part comprises a first curved surface, wherein the second part comprises a second curved surface that intersects with the first curved surface at a region between the first part and the second part, wherein the first part and the second part each have a peak relative to the substrate, the peak being spaced from the region between the first part and the second part, and wherein the third part extends beyond the region between the first part and the second part in a direction away from the associated LED;
• and
• a heat sink thermally coupled to a second surface of the substrate, the second surface opposite the first surface, the heat sink comprising a first section substantially parallel to the substrate so that each and every LED of the plurality of LEDs is separated from the heat sink by the substrate, the heat sink further comprising a plurality of fins extending away from the first section and substantially perpendicular thereto, wherein the first section of the heat sink includes a portion that extends past the substrate in a direction away from the fins.

A method of illuminating visual media content on a billboard display surface using a lighting assembly that comprises a power supply and a lighting unit that includes a substrate, a plurality of light emitting diodes (LEDs) arranged on the substrate, a plurality of optical elements, and a heat sink, the method comprising:

• directing light from the LEDs toward a portion of the billboard display surface such that the light from the lighting unit illuminates the visual media content on the portion of the billboard display surface with an illumination level and a uniformity;
• and
• directing heat generated by the LEDs away from the optical elements using the heat sink;
• wherein the plurality of LEDs are arranged in a plurality of rows on a first surface of the substrate, the rows extending along a longitudinal axis in a plane of the first surface of the substrate;
• wherein each optical element of the plurality of optical elements is proximate an associated LED of the plurality of LEDs such that each optical element overlies a single LED and each LED underlies a single optical element;
• wherein each optical element of the plurality of optical elements is separate from other optical elements of the plurality of optical elements;
• wherein each optical element includes a first part, a second part and a third part;
• wherein the first part comprises a first curved surface;
• wherein the second part comprises a second curved surface that intersects with the first curved surface at a region between the first part and the second part, wherein the first part and the second part each have a peak relative to the substrate, the peak being spaced from the region between the first part and the second part;
• wherein the third part extends beyond the region between the first part and the second part in a direction away from the associated LED;
• wherein the heat sink is thermally coupled to a second surface of the substrate, the second surface opposite the first surface;
• wherein each and every LED of the plurality of LEDs is separated from the heat sink by the substrate;
• wherein the heat sink comprises a first section substantially parallel to the substrate and a plurality of fins extending away from the first section and substantially perpendicular thereto;
• and
• wherein each fin extends along an axis in the plane of the first surface of the substrate, the axis for each fin being substantially perpendicular to the longitudinal axis of the first surface of the substrate.