US Patent 10984969 Uniform illumination of keys on a flexible substrate

Systems and methods for providing illumination to illuminable portions of keys associated with a keyboard are described. A key disposed on a flexible substrate includes a light guide positioned below a keycap. The light guide includes one or more light extraction features to produce a substantially uniform light distribution of light from a light emitting element at an illuminable portion of the key. In one embodiment, a light emitting element is positioned on the flexible substrate and is optically coupled to the light guide. In another embodiment, a light emitting element is positioned below the flexible substrate and is optically coupled to the light guide via an optical interface.