Back to results
US 7,832,896 B2Granted
LED light engine
AssigneeLumination LLC
InventorsKoushik Saha, Jeffrey Nall, Mark J. Mayer, Chunmei Gao, Kevin Carpenter, Shanshan Xie, Yiyu Cao, John Owens
Life of this patent
Estimating the term…
Abstract
A light engine comprises a plurality of LEDs and a plurality of optical elements each cooperating with a respective LED. The optical elements broaden the off-axis angle from the respective LEDs to provide a more uniform illumination at a target plane.
Claims21
A light engine for illuminating a target plane at a defined uniformity, the light engine spaced from the target plane a distance D and comprising:
- a plurality of LEDs arranged in adjacent rows spaced from one another by a distance W, each of the LEDs having an off-axis angle β1 defined by a half intensity boundary where luminous intensity of the LED on a plane is about half the luminous intensity on the plane at the direct on-axis view, wherein tan β1<(W/2)/D;
- and
- a plurality of optical elements each cooperating with a respective LED to broaden the off-axis angle β1 to an off-axis angle β2 wherein the half intensity boundary of one row of LEDs is in close proximity to the half intensity boundary of the adjacent row of LEDs at the target plane.
A method for illuminating a sign comprising:
- placing a plurality of electrically interconnected LED modules in a sign having a translucent cover, each LED module including an LED and an optical element cooperating the with LED, each LED having an off-axis angle β1 where luminous intensity of light emanating from the respective LED that is not redirected by the respective optical element is about half the luminous intensity of on-axis luminous intensity for the respective LED;
- spacing each LED a distance D from the translucent cover;
- arranging the LED modules in adjacent rows such that adjacent LEDs are spaced from one another a distance W, wherein tan β1<(W/2)/D;
- and
- illuminating the plurality of LEDs to generate a plurality of beam patterns on the translucent cover by redirecting light from each LED via the respective optical element to have off-axis angle β2 where luminous intensity of light emanating from the respective LED that is redirected by the respective optical element is about half the luminous intensity of on-axis luminous intensity for the respective LED and the respective optical element, wherein a first beam pattern on the target plane generated by the first LED in combination with a first optical element in the first row and bounded by the off-axis angle β2 overlaps or coincides with a second altered beam pattern on the target plane generated by the second LED in combination with a second optical element in the adjacent row and bounded by the off-axis angle β2.
2 more elements
A light engine comprising:
- a plurality of electrically interconnected LED modules, the LED modules including
- a support having circuitry on a first surface;
- an LED on the first surface of the support and electrically connected to the circuitry, the LED having a primary viewing angle;
- a substantially dome-shaped refractive optical element covering the LED, the optical element having a generally spherical outer profile and substantially ellipsoidal inner profile to increase the primary viewing angle of the LED to provide an altered viewing angle that is greater than the primary viewing angle;
- and
- an overmolded housing substantially surrounding said support and contacting the optical element to seal the LED protecting the LED from ambient.
3 more elements
A light engine for illuminating a target plane at a defined uniformity, said light engine spaced from the target plane a distance D and comprising:
- a plurality of LEDs arranged in adjacent rows spaced from one another by a distance W, each of the LEDs having an off-axis angle β1 defined by a boundary where the luminous intensity of the LED is about half the intensity at the direct on-axis view, wherein tan β1<(W/2)/D;
- and
- a plurality of optical elements each cooperating with a respective LED to broaden the off-axis angle β1 to an off-axis angle β2 wherein tan β1 is about (W/2)/D.
Dependencies are inferred from the claim text.