TW200834136A - Light guide method of double-layer light guide plate and keypad structure using the double-layer light guide plate - Google Patents

Abstract

A keypad structure having a double-layer light guide plate of different sizes includes a circuit board, a reflecting plate, a second light guide plate, a second light guide plate, a shading strip, a first light guide plate, an elastic layer, a keypad module and a light source module. A shading strip is attached around the periphery of the second light guide plate for attaching the second light guide plate at the bottom of the first light guide plate. A hole is disposed at an overlapped position of the first light guide plate and the second light guide plate that exposes the second light guide plate, and a light emitting element is installed correspondingly at the exterior of each of the two light guide plates. If the light emitting element of the second light guide plate is lit, the second light guide plate will produce a single-color light emission, and the light is collected and projected onto a keypad corresponding to the second light guide plate. If the light emitting element of the first light guide plate is lit, the light emitting element will produce different color lights, such that a light transmission effect of single-color light or mixed multiple-color light is produced at the surface of the keypad corresponding to the first light guide plate.