Average power, its why PWM dimming works on LEDs well, LEDs make a good strobe into Mhz , but to keep average power up you start dumping very large currents through them.
Big LEDs prefer to be current driven, the pulsing thing is a bit of red herring, PWM, a Philips Patent in the U.S., is used for dimming and for people who read pulsed lumens from the data sheet like a light meter not a human.
Cheers Adam
We just had red LEDs (not lasers), so may not have been that efficient. We were after the maximum efficiency so we could send a beam across a long room to transmits voice (we used PWM too, but kept down to the tens of kHz). The only reason for the PWM was to give the receiver somethigb to "lock onto".
Even a laser will drop when modulated , energy is more directionally concentrated but few lasers are going to get an A efficiency label ;-)
Modern LEDs are a heck of a lot more efficient and probablya bit more robust, but the tnking generally goes along the lines of 20mA continuosly, 100mA pulsed, 1000mA really short pulse...
Cheers Adam
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