Method of uniformly illuminating a billboard

摘要

Visual media content on a billboard display surface can be illuminated using a lighting assembly that includes a lighting unit that includes a circuit board, LEDs arranged on the circuit board, and optical elements overlying the LEDs. The method includes directing light from the lighting unit 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. The optical elements are configured so that failure of one or more LEDs of the lighting assembly will cause the illumination level of light impinging the portion of the billboard display surface to decrease while the uniformity of light impinging the portion of the billboard display surface remains substantially the same.

主权项

1. A method of illuminating visual media content on a billboard display surface using a lighting assembly that comprises a first lighting unit and a second lighting unit that each include a circuit board, a plurality of LEDs arranged on the circuit board, and a plurality of optical elements, wherein each optical element overlies a respective one of the LEDs and wherein each optical element is configured to redirect light from the respective one of the LEDs, the method comprising:
directing light from the first lighting unit toward a portion of the billboard display surface such that the light from the first lighting unit illuminates the visual media content on the portion of the billboard display surface with an illumination level and a uniformity, wherein the portion of the billboard display surface is substantially rectangular and wherein the light is directed so that areas beyond edges of the portion of the billboard display surface receive minimum illumination; and at the same time as directing the light from the first lighting unit, directing light from the second lighting unit toward the portion of the billboard display surface such that the light from the second lighting unit illuminates the visual media content on the portion of the billboard display surface; wherein the optical elements are configured so that failure of one or more LEDs of the lighting assembly will cause the illumination level of light impinging the portion of the billboard display surface to decrease while the uniformity of light impinging the portion of the billboard display surface remains substantially the same; and wherein if one or more LEDs of the plurality of LEDs of the second lighting unit fails, remaining LEDs of the plurality of LEDs of the second lighting unit still illuminate the portion of the billboard so that the visual media content on the portion of the billboard display surface is visible.