Design of axisymmetrical tailored concentrators for LED light source applications

Abstract

In our contribution we present a solution to an important question in the design of a LED-based illumination engine for projection systems: the collimation of the LED light. We tested the principle in the modification of a common device in non-imaging optics, the compound Parabolic Concentrator. This CPC-like achieves a collection of 72% (ideal reflective coating presumed). This CPC-like was tailored by numerically solving an differential equation. This approach has some serious drawbacks. For a compact collection device with high collimation, an other approach is required. A more elegant design strategy will rely fully on geometrical principles. The result of our work is a compound collection lens that achieves a collection efficiency of 87%, assuming an ideal reflective coating and neglecting Fresnel losses. We study the performance of this device in detail. Further enhancements are suggested.

An algorithm to minimise the beam angle of compound parabolic concentrators with LED sources

“…1 When the CPC is used as a reflector for a LED source, its advantage lies in its high efficiency. 2 It has been widely used in many fields such as coupling LED radiation into optical fibres, 3 pumping lasers, 4 designing a reflectometer 5 and automotive forward lighting. 6 The references above have mainly studied the efficiency and luminous intensity distribution of CPCs.…”

Design and Manufacture of Light Collimator with Narrow View Angle

“…The fundamental approach in LED beam forming optics is represented by light collimation through well-developed optical design and manufacturing technologies. Recently, optical researchers have extended traditional lens design methodology to include secondary optics design of LEDs and beam forming lenses such as aspheric double let lenses, as well as tailored and compact concentrators [4][5][6][7]. However, despite such technical advancements, the difficulty of having extremely sharp gradients in luminous intensity patterns still exists.…”