Advancements in Flexible Display Technology
If you look at a flexible display or any foldable device, you may wonder how it works. At the heart of any screen, whether curved or flat, folding or not, is a PCB that enables it to function as intended. At Rush PCB Inc, we want to make sure you have all the information you need about the technology behind these new screens.
How did PCBs become what they are today, a critical part of every computer and digital device on the planet? It’s actually largely due to the military. As the Cold War and heightened tensions with the Soviet Union escalated, the U.S. Army needed to boost its ability to communicate with its soldiers in remote areas of the world, and pcb board were one of the technological solutions it developed to accomplish this goal.
These early boards were made by placing small integrated circuits (ICs) and other discrete components on a rigid substrate that was initially a material called bakelite. They had many wired connections that often got tangled together, and their complexity meant that debugging was difficult and reliability suffered. In addition, they were difficult to manufacture, as they were a complex assembly of copper traces and through-holes that held large, bulky components.
How Do PCBs Enable Advancements in Flexible Display Technology?
As technology advanced, however, it became possible to shrink the size of these ICs and other discrete components. This was facilitated by new materials that were both denser and thinner than their rigid predecessors, which allowed for the creation of smaller, more compact PCBs. As a result, these new boards could be made with less expensive components and soldered to each other much faster than their older counterparts, dramatically decreasing the time it took for engineers to get a product to market.
Another significant development came with the invention of high-density interconnect (HDI) design. These are complex designs that contain thousands of connections and multiple electrical interfaces, powering everything from smartphones to heart rate monitors to rockets. The challenge with these is that they have to be as dense and compact as possible, while ensuring that all the active components are connected to both their respective power and ground planes. This is done by flooding certain areas or layers with solid copper plating, known as the base layer, and then drawing a wiring pattern on it with acid-resistant ink. This is then photographed on a zinc plate and used as a model to create more of the same PCBs.
As the industry continued to evolve, engineers began to use a type of PCB that is referred to as flex PCB or flexible printed circuit board. These are not rigid and can bend and twist without breaking, making them ideal for a variety of uses in electronic devices. They also require fewer solder joints, which decreases the risk of failure and increases efficiency and performance.
A flex PCB can be built with a variety of different coatings, including copper plating, coverlay placement, and stiffeners. The latter are thin layers of copper that help to support a flex PCB during the drilling and soldering process, allowing for higher manufacturing speeds. These benefits and others have helped the flex PCB market to grow into what it is today, dominating the global electronics market in terms of production volume.
