InteLED’s Technology Foundation
Optimized Optics for LED Lighting
Non-imaging optics is a breakthrough optical design method that eliminates the requirement of forming an image, and in so doing can deliver better and more efficient collection of light, superior uniformity, and more compact devices, all the while meeting the demanding requirements of cost, manufacturability, and reliability. InteLED can typically supply a final design to a client within a 4-week time frame from receipt of PO and Statement of Work.
LEDs by their very nature are quite small and thus are easily integrated with optical systems. In general, the smaller the light source the easier a given optical lens can form a useful beam. Thus the large size of conventional light sources precludes all but an occasional large reflector, since only glass can withstand their heat and glass lenses are far too expensive. Even with reflectors, much light is typically wasted in conventional luminaires, often the majority of light going where it is not used. Consequently LEDs enjoy a fundamental advantage over previous light sources because their intrinsically small size enables injection-molded plastic lenses to be utilized, making them more price-competitive on a delivered-lumen basis.
Optics can broadly be divided into the two fields of imaging and non-imaging optics. Imaging optics is a 300-year-old discipline concerned with the reproduction of spatial information. As the lighting industry developed in the 19th century it was natural to incorporate imaging optics into new lighting systems, both parabolas for searchlights and flashlights and Fresnel lenses in lighthouses. Both of these, however, only collect about 40% of the light leaving a light bulb in all directions. The other 60% of the light is wasted, in the case of the flashlight going straight out as glare, a particularly unwanted aspect of automobile headlights.
In non-imaging optics throwing out the imaging constraint enables an illumination system to be more efficient and compact than an imaging version. It is not unusual for non-imaging optics to be 50%- 150% more efficient than corresponding imaging systems, while also being much more compact. The figures below show two examples of non-imaging lenses.
On the left is the total internal reflection (TIR) lens, invented by InteLED’s principals. It captures almost 100% of the light hemispherically leaving the LED and yet is very thin. On the right is the Black Hole lens, another compact non-imaging lens invented by InteLED’s principals, which also uses TIR, to redirect the LED’s light into a 360-degree lighthouse pattern.
InteLED’s On-going Development
InteLED’s technology development team continues to develop unique and state of the art non-imaging optical designs and technologies to serve different markets needs in lighting system. From down light to fluorescent replacement, from biomedical equipment to aerospace technologies and other lighting needs, InteLED has the experience and know-how to improve the efficiency and performance with enhanced optical system, thermal design, and full product integration for LED lighting system. For more information on licensing, product development and optical design and products, please contact us.