What's the Best Backlighting for a Membrane Switch?
Membrane switches are found just about everywhere. Characterized by conductive screen, usually featuring ink such as copper, silver or graphite, it differs from its mechanical switch counterpart in the sense that it conducts electricity. You can find membrane switches in microwave ovens, household appliances, air conditioners, TV remotes, human machine interfaces and more.
In order for a membrane switch to function as intended, however, it must feature some type of backlight. The purpose of a backlight, as the name suggests, is to illuminate the back of the switch, allowing the operator to see it more easily. There are several different types of membrane switch backlights, each of which has its own specific purpose. To learn more about the different backlights and which one is best suited for membrane switches, keep reading.
There are generally three different backlights used in membrane switches: light-emitting diodes (LEDs), optical fiber and electroluminescent. LEDs are energy-efficient, easy to use and readily available, making them the preferred choice among many professionals. With that said, however, LEDs are susceptible to bright spots, as some areas of the membrane switch may feature bright colors than other areas. On the plus side, however, LEDs can either be mounted to the surface of the membrane switch or applied to a separate layer.
Optical fiber is another popular choice of backlighting used in membrane switches. It features two or more layers of fiber optics that create a light-emitting area. The fibers are bundled at the end to create a circular ferrule, at which point they are attached to an LED. Some optical fiber backlights can last for up to 100,000 hours, at which point they must be replaced. Optical fibers are also resistant to moisture, humidity and extreme temperature changes, making them an excellent choice for outdoor applications.
