https://www.theguardian.com/technology/2020/nov/22/eddie-yeadon-obituary

My brother Eddie Yeadon, who has died aged 82, was an engineer and physicist with a particular interest in optics and astronomy.

In the late 1960s he worked in the US for the optics company Perkin Elmer on the visors for the helmets used in the Apollo 11 moon landings. He also designed a reflector left on the moon to “bounce” a laser beam. He often joked that this was the part of the mission which did not work (although it was used subsequently).