@Jencen @kieran I worked in the class 100 clean room at the Plumbicon tube manufacturing facility owned by Philips in Slatersville, RI. It was a college internship. My father was a sales engineer for Amperex which became Philips Electronics, and I used a microscope to measure the depth and angle of the grid that detected the photons to determine if there was any regularity to the individual, hand crafted blown glass tubes. (There wasn’t much. :)

A good amount of equipment salvaged by my father made its way to Emerson College and then to the broadcast museum in Woonsocket, RI.