In the early 1960s LEED experienced a renaissance, as ultra-high vacuum became widely available, and the post acceleration detection method was introduced by Germer and his coworkers at Bell Labs using a flat phosphor screen. Using this technique, diffracted electrons were accelerated to high energies to produce clear and visible diffraction patterns on the screen. Ironically the post-acceleration method had already been proposed by Ehrenberg in 1934. In 1962 Lander and colleagues introduced the modern hemispherical screen with associated hemispherical grids. In the mid 1960s, modern LEED systems became commercially available as part of the ultra-high-vacuum instrumentation suite by Varian Associates and triggered an enormous boost of activities in surface science. Notably, future Nobel prize winner Gerhard Ertl started his studies of surface chemistry and catalysis on such a Varian system.