Wikipedia's Lunar Laser Ranging Experiments; History mentions the first lasers ever bounced off the whole Moon were in 1962, and probably both the US and Soviet groups used Q-switched ruby lasers.
In 1969 the Apollo astronauts placed an array of optical retroreflectors on the moon and carefully oriented it so that the face of the array pointed towards the mean direction of the Earth so that each reflector's contribution would be returned at nearly the same time. See What are these structures on the Lunar Ranging Retro Reflector (LRRR) arrays for? for lots of details.
On the ground almost certainly photomultiplier tubes were used at the focus of the telescope receiving the pulses. I'm guessing that they dealt with reflected sunlight by waiting until the Apollo 11 site was not sunlit, and a combination of a pinhole and filter for the laser wavelength, as well as some nice gated coincidence electronics.
But I have no idea, so I'd like to ask:
Question: How did the earliest measurements of lasers bounced off of Apollo 11 retroreflectors deal with the light from the Moon and pick out single photons?
A photo of the receiving system optics would be great!
- What laser technology/ies were first used to bounce off of the Apollo 11 retroreflectors to accurately measure distance to the Moon?
For more on the Apollo 11 retroreflectors themselves see