An illuminating device producing an asymmetrical light intensity distribution comprising: a circular light guide (24, 44, 46, 72) having a perimeter; a plurality of light emitting diodes (LEDs) mounted proximate to at least a portion of the perimeter of the light guide so as to inject light into the circular light guide, the plurality of LEDs being divided into at least two segments of LEDs, a first segment of the at least two segments of LEDs being mounted in a first arc along the perimeter of the circular light guide, a second segment of the at least two segments of LEDs being mounted in a second arc along the perimeter of the circular light guide, the first and second segments of LEDs being designed or controlled to emit different amounts of light; a diffuser on a light-emission surface of the light guide, the diffuser producing a Gaussian emission, which maintains a directionality of an impinging light ray while diffusing the light ray; and a plurality of linear grooves (40, 43, 45) formed in the surface of the circular light guide opposite the light-emission surface, the plurality of linear grooves being parallel one another and spaced apart from one another extending along a width of the circular light guide, each of the plurality of linear grooves having an angled surface, for directing light toward the light exit surface of the light guide, and each of the plurality of linear grooves having a surface substantially perpendicular to the light emitting surface of the light guide, wherein the first segment of LEDs mounted in the first arc along the perimeter of the circular light guide generate first incident light rays that are directed by the angled surfaces of the grooves toward the light emitting surface to primarily contribute to the front emission and side emissions of the light guide, wherein the second segment of LEDs mounted in the second arc along the perimeter of the circular light guide generate second incident light that is reflected back towards the second LEDs by the surfaces of the grooves that are substantially perpendicular to the light emitting surface to also primarily contribute to the front emission and side emissions of the light guide, wherein the plurality of LEDs, the diffuser, and the linear grooves are configured to produce an asymmetrical light intensity distribution comprising the front emission, the back emission, and the side emissions, wherein the side emissions have a peak intensity that is at least twice that of the front emission, and the peak intensity of the back emission is less than that of the front emission. a circular light guide (24, 44, 46, 72) having a perimeter; a plurality of light emitting diodes (LEDs) mounted proximate to at least a portion of the perimeter of the light guide so as to inject light into the circular light guide, the plurality of LEDs being divided into at least two segments of LEDs, a first segment of the at least two segments of LEDs being mounted in a first arc along the perimeter of the circular light guide, a second segment of the at least two segments of LEDs being mounted in a second arc along the perimeter of the circular light guide, the first and second segments of LEDs being designed or controlled to emit different amounts of light; a diffuser on a light-emission surface of the light guide, the diffuser producing a Gaussian emission, which maintains a directionality of an impinging light ray while diffusing the light ray; and a plurality of linear grooves (40, 43, 45) formed in the surface of the circular light guide opposite the light-emission surface, the plurality of linear grooves being parallel one another and spaced apart from one another extending along a width of the circular light guide, each of the plurality of linear grooves having an angled surface, for directing light toward the light exit surface of the light guide, and each of the plurality of linear grooves having a surface substantially perpendicular to the light emitting surface of the light guide, wherein the first segment of LEDs mounted in the first arc along the perimeter of the circular light guide generate first incident light rays that are directed by the angled surfaces of the grooves toward the light emitting surface to primarily contribute to the front emission and side emissions of the light guide, wherein the second segment of LEDs mounted in the second arc along the perimeter of the circular light guide generate second incident light that is reflected back towards the second LEDs by the surfaces of the grooves that are substantially perpendicular to the light emitting surface to also primarily contribute to the front emission and side emissions of the light guide, wherein the plurality of LEDs, the diffuser, and the linear grooves are configured to produce an asymmetrical light intensity distribution comprising the front emission, the back emission, and the side emissions, wherein the side emissions have a peak intensity that is at least twice that of the front emission, and the peak intensity of the back emission is less than that of the front emission.