A modern dental X-ray tube. The heated cathode is on the left. Centre is definitely the anode which is made from tungsten and embedded during the copper sleeve.William Coolidge clarifies clinical imaging and X-rays. An X-ray tube can be a vacuum tube that converts electrical input electric power into X-rays.[1] https://edgetech-industries-eti43209.win-blog.com/8196098/edgetech-industries-eti-an-overview