Silicone rubber keypads are a popular choice for human machine interfaces (HMIs) and other control systems. Also known as elastomeric keypads, they are characterized by the use of angled silicone rubber webbing that’s installed around a switch. Pressing the keypad causes the soft webbing to collapse, and releasing the keypad causes it to revert back to its original shape. Even if you’re familiar with the general concept of silicone rubber keypads, though, there are probably some other things that you don’t know about them.
#1) They Support Laser Etching
The surface of silicone rubber keypads supports laser etching for a deeper level of customization. This process involves the use of a high-temperature laser to remove specific areas of the switch’s top coat. As these areas are removed, it reveals the underlying layer, which is a different color. And the presence of these two layers creates visual graphics for the silicone rubber keypad.
#2) They Produce Tactile Feedback
The way in which silicone rubber keypads are designed allow them to produce tactile feedback when pressed. Pressing the keypad causes the silicone rubber webbing to bend and deform. And due to the characteristics of this material, releasing the keypad causes it to snap back into place. Although subtle, this tactile feedback helps to reduce user errors and improve user satisfaction.
#3) Some Support Backlights
Some types of silicone rubber keypads support backlights, such as electroluminescent (EL) or light-emitting diode (LED). The addition of a backlight improves the keypad’s visibility by illuminating it from underneath. If the silicone rubber keypad is going to be used outdoors at night or in other low-light conditions, a backlight may be included for this reason.
#4) They Are Long Lasting
To say silicone rubber keypads simply “last a long time” would be an understatement. It’s not uncommon for a silicone rubber keypad to last for tens of thousands of presses. This is because silicone rubber is strong and durable while still being able to flex and bend. As long as it’s properly maintained, a silicone rubber keypad will offer many years of use.
#5)They Are Most Common In Mobile Phones
The single most common application for silicone rubber keypads is mobile phones. Mobile phones with physical buttons — not a touchscreen interface — typically use a silicone rubber keypad because of its flexible and water-resistant properties. Of course, you’ll find these keypads available in many other products, some of which include TVs, electronic toys and industrial equipment.