Apparatus and method for improved illumination area fill
A reflector for a light source, such as an LED, is provided with a shape which efficiently collects and directs energy to an illumined surface whereby almost 100% of the light is collected and distributed into a designer composite beam. The shape in one embodiment is comprised of three zones beginning with a parabolic surface of revolution at the base of the reflector, followed by a transition or straight conic zone and ending with an elliptical zone. In another embodiment the reflector shape is determined according to a transfer function which allows for arbitrary designer control of the reflected rays at each point on the reflector, which when combined with direct radiation from the source, results in a designer controlled composite beam or illumination. The device is more than 90% energy efficient and allows replacement of higher power, less energy efficient light sources with no loss in illumination intensity.
1. An apparatus for illuminating a illumined surface comprising:
a light source whose intensity varies as a function of the angles of the light rays radiated from the light source in a three dimensional radiation pattern, and
a reflector having a base and aperture, the reflector being proximate to the light source, defining a system half angle by the optical aperture of the reflector and allowing directly radiated energy to propagate from the light source through the optical aperture of the reflector to the illumined surface to provide a directly radiated energy distribution pattern on the illumined surface, the reflector having three distinct shaped zones, each zone providing a surface of revolution, the first zone being a parabolic surface of revolution, the second zone being a straight line surface of revolution and the third zone being an elliptical surface of revolution, in that order, beginning with the base of the reflector and moving toward the optical aperture of the reflector, without necessity of smooth transitions between the adjacent zones to allow freely controlled reflected energy distribution pattern to be overlaid onto the directly radiated energy distribution pattern on the illumined surface, which reflected energy distribution pattern combines with the directly radiated energy distribution pattern to produce a freely controlled composite energy distribution pattern on the illumined surface; and
a solid or stranded optical fiber where the freely controlled composite energy distribution pattern is coupled into the solid or stranded optical fiber.
2. An apparatus for illuminating a illumined surface comprising:
a light source whose intensity varies as a function of the angles of the light rays radiated from the light source in a three dimensional radiation pattern, and
a reflector having a base and aperture, the reflector being proximate to the light source, defining a system half angle by the optical aperture of the reflector and allowing directly radiated energy to propagate from the light source through the optical aperture of the reflector to the illumined surface to provide a directly radiated energy distribution pattern on the illumined surface, the reflector having three distinct shaped zones, each zone providing a surface of revolution, the first zone being a parabolic surface of revolution, the second zone being a straight line surface of revolution and the third, zone being an elliptical surface of revolution, in that order, beginning with the base of the reflector and moving toward the optical aperture of the reflector, without necessity of smooth transitions between the adjacent zones to allow freely controlled reflected energy distribution pattern to be overlaid onto the directly radiated energy distribution pattern on the illumined surface, which reflected energy distribution pattern combines with the directly radiated energy distribution pattern to produce a freely controlled composite energy distribution pattern on the illumined surface; and
a light fixture in which the light source and reflector are included.
3. The apparatus of claim 2 where the tight fixture comprises, a street lamp, an array, or an LCD panel light, signage light, airplane light, auto light, marine light, indoor or outdoor architectural light, decorative light, task light, or flood light.