LED Prototypes for Headlights
Oct 2011OSRAM Opto Semiconductors Inc.Request Info
SUNNYVALE, Calif., Oct. 13, 2011 — Osram Opto Semiconductors has developed two LED prototypes that combine new chip and package technologies to provide high light output, even at high currents; a uniform light pattern; thermal stability; and a good contrast ratio. They are matched to the requirements of headlight systems and are designed to provide headlight manufacturers with good performance and optimized cost.
More and more flexibility is needed for the light sources used in headlights. Not only must they be reliable and provide the appropriate amount of light in all visibility and driving conditions, but they also must adjust to changing ambient conditions, including high temperatures in the headlight itself. The company has developed the OSLON Black Flat and Osram OSTAR Headlamp Pro to meet all of these requirements.
OSLON Black Flat is equipped with a ceramic converter and a quad flat no-lead package. Typical thermal resistance is 5 K/W. The black package represents high stability because the coefficient of thermal expansion of the LED matches the coefficient of expansion of the metal core board. The flattop, lens-free design is suitable for the close coupling required for lightguide designs and maximizes the incoupling of light. The solder pad is identical to that of the other members of the OSLON family, which enables light output from a largely identical board design. With a power draw of 2.3 W and an operating current of 700 mA, it achieves a typical luminous flux of 190 lm.
The OSTAR Headlamp Pro meets a variety of requirements in terms of output and adaptability to ambient conditions. It offers a uniform light pattern, good thermal stability (more usable warm lumens) and high brightness. The 20 × 20-mm high-flux LED is available in two- to five-chip configurations.
The OSTAR LED’s adaptive front-lighting system can now be achieved with chips that can be controlled individually or in series, enabling chip matrix solutions. Typical luminous flux values are around 250 lm for a single chip (1-A operating current), equating to 1250 lm for the five-chip version, whose thermal resistance is 2.1 K/W.
The design uses proprietary UX:3 chip technology and a ceramic converter that provides a uniform light pattern. The package produces a defined light/dark boundary in the light pattern, providing a good contrast ratio for simpler and improved optical designs.