Popis: |
The market entrance of thinfilm based, substrate-less LEDs has stimulated the field of high-brightness LEDs. One of the most prominent advantages of thinfilm LEDs is the possibility to achieve a high light extraction efficiency independently of the chip area. This feature is particularly suitable for large-area, high-flux devices. In this paper, we report on high-power LEDs with a chip-area of 1 mm 2 for red and infrared emission. Mounted in packages with improved heat sinking and operated at a continuous-wave (cw) current of 800mA, the devices achieve an output power of 440 mW both for red (λ = 615 nm) and infrared (λ = 850 nm) wavelengths. Together with Osram's ThinGaN chips, a family of devices is available with very similar emission characteristics, performance and geometry, which allow the assembly of powerful light engines for a number of advanced applications. |