Q) What are the different methods of backlighting a membrane switch?

A) Pannam has several different methods for backlighting your membrane switch each having its advantages and disadvantages:

LED (Light Emitting Diodes) – LED's are surface-mounted using silver conductive epoxy. LED's are used when selectively backlighting text and graphics. LED backlighting, in most cases, is a lower cost alternative to other backlighting technologies.

Electroluminescence (EL) – EL uses a printable ink (embedded with light emitting phosphors) to illuminate the membrane switch. Therefore it is a very thin layer and emits very little heat. It can be cut to any shape and easily layered within the membrane switch. Popular EL applications are the Timex Indigo Watch, automotive dash lighting, mobile phones and pagers.

Fiber Optic – Pannam uses sheets of Fiber Optic Cloth cut into specific sizes and shapes to create a thin flexible lighting layer that goes between the overlay and dome switches. The optical fibers coming off one end of the panel are bundled into a circular ferrule and coupled to one or more LED light sources. Fiber optic backlighting attributes are long life, low power, compact size, low heat, high durability, low start-up costs and design flexibility.