The printed circuit board was crucial to the development of technology in the 20th century, although most people may not have become aware of them until the 1980s, when the first personal computers began to emerge. In fact, the first electronic apparatus that could be called a printed circuit board appeared in 1903, when German scientist Albert Hanson filed a patent in England for his basic circuit board that he made for use in telephone systems.
This board consisted of a flat piece of foil attached to printed wires bonded to paraffin paper. The board did have through-hole construction and conductors on both sides, just like plated through-hole PCBs today.
When Did the Modern Circuit Board Emerge?
It started in 1927 with Charles Ducas, who patented a version of the circuit board. He used a stencil to print wires onto a board with conductive ink, placing an electronic path right onto an insulated surface. He called it printed wiring, and it was the precursor to today’s electroplating.
However, the credit for inventing the modern printed circuit board goes to Paul Eisler. Eisler had a background in printing, and was captivated by the idea of printing actual electronic circuits onto boards rather than soldering the wire on by hand. Unfortunately, the Jewish Eisler was distracted by the rise of Nazism, which forced him to flee from Austria in 1936 to the not-so-friendly confines of England.
After spending time in prison for being an illegal immigrant, he finally found work at a music printing company in 1941, where he tested his printed circuit board idea on a typewriter. It worked, and he was able to get the company to invest. The British and American governments quickly saw the military applications of Eisler’s invention, and they became invaluable during World War II, as the Allies used them to improve radios and the efficacy of anti-aircraft shells.
What Happened With PCBs After World War II?
After World War II, the United States set its eyes on the final frontier: space. Printed circuit boards made space exploration possible in a way people had never considered before. Printed circuit boards significantly increase the efficiency of spacecraft, because they are low-weight and do not use a lot of electricity, even when performing very complicated tasks. Weight and energy are huge issues on a spacecraft, which is why PCBs were so popular. NASA used them during the Apollo program of the 1960s, and they traveled to the moon with Armstrong, Aldrin and Collins in 1969.
How Did PCBs Move From the Military to the Consumer World?
So how did printed circuit boards become what they are today, a vital part of every computer and digital device on the planet? We actually have the military to thank. The U.S. Army Signal Corps managed to figure out a way to speed up the production of PCBs with auto-assembly. This is a process wherein the manufacturer laminates a layer of copper foil to the base material and draws a wiring pattern on with acid-resistant ink. When the copper not protected by the ink is removed, the printed copper wires remain. The manufacturer then photographs the pattern onto a zinc plate to use as a model for printing more copies of the board.
This process made the creation of PCBs much, much faster, which made it highly economical for the consumer electronics industry to use them.