It’s not uncommon for silicone rubber keypads to feature backlighting. Located behind the individual keys, the backlighting is responsible for illuminating the keypad. But how exactly does backlighting work in silicone rubber keypads?

Overview of Silicone Rubber Keypads

Before we reveal the mechanics of backlighting, let’s first take a closer look at silicone rubber keypads. Also known as an elastomeric keypad, a silicone rubber keypad is a type of electrical switch that’s characterized by the use of silicone rubber for the webbing material.

Each key on a silicone rubber keypad acts as an electrical switch. Underneath each key is an electrical contact that, when pressed, touches its corresponding contact below to complete the electrical switch. The webbing material used to separate the keys from their corresponding contacts is made of soft silicone rubber material.

The Basics of Backlighting in Silicone Rubber Keypads

While there’s no rule, written or unwritten, stating that silicone rubber keypads must feature backlighting, many of them do. Business owners and consumers often prefer to use keypads with backlighting because they are easier to see. If a keypad is used outdoors or in other poorly lit environments, the use of backlighting can improve its visibility.

Silicone rubber keypads support a wide variety of backlighting configurations. One of the most popular types of backlighting for silicone rubber keypads is light-emitting diode (LED). With LED backlighting, LED bulbs are installed behind the silicone rubber keypad’s keys. When activated, the LED bulbs will illuminate the keys from underneath to improve visibility and, therefore, ease of use.

LED is preferred over other backlighting technologies because of its energy-efficient properties. Furthermore, though, LED bulbs last a long time. While other backlighting technologies have a relatively short lifespan, LED can last for tens of thousands of hours.

LED backlighting for silicone rubber keypads may consist entirely of LED bulbs, or it may consist of a combination of both LED bulbs and light guides. Light guides don’t produce illumination but, instead, are designed to evenly distribute light across the keypad. The focused light produced by LED bulbs enters the light guides where it’s evenly distributed across the keypad. Light guides are beneficial because they color distortion while also promoting greater energy efficiency. If a silicone rubber keypad uses light guides, it won’t need as many LED bulbs, thereby making it more energy efficient.