JohnD
0
- Joined
- Jun 17, 2010
- Messages
- 51
- Points
- 0
The "wattage" isn't that applicable with these experiments.
They want time measurements, so they want pulses as short as possible, but a lot of power in that short pulse since they get VERY few photons back. The APOLLO measurement set-up generally uses a 90 picosecond pulse with a pule energy of ~115 mJ. So during the pulse, that's ~1.3 gigawatts, but it only does that 20 times per second, so that's a time-average of about 2.3 Watts.
And their optics matter: they're using a 3.5 meter telescope as a beam expander to get lower divergence.