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>"Osram has developed a small light-emitting diode spotlight that
>achieves an output of more than 1,000 lumens for the first time. That?s
>brighter than a 50-watt halogen lamp, thereby making the device suitable
>for a broad range of general lighting applications."
Keep in mind they said 75 lumens/watt at 350 mA, and that this is a
6-chip device. At 350 mA, chips of higher efficiency tend to have voltage drop around 3.3 volts - otherwise 3.5 volts is usual. So at 350 mA, the voltage drop is close to 20 volts, and the power is close to 7 watts. At
75 lumens/watt, 7 watts gives 525 lumens.
To get 1,000 lumens, current closer to an amp is required, with overall luminous efficacy not 75 lumens/watt but in the 50's. (I have seen other announcements on this product.) If this thing achieved 75 lumens/watt at enough power to deliver 1,000 lumens, they would not have qualified 75 lumens/watt at a current only good for 525 lumens.
- Don Klipstein ( snipped-for-privacy@misty.com)