Keyboard device

A keyboard device, comprising:

• plural key structures, wherein each of the key structures comprises a keycap, and the keycap has a first end surface and a second end surface, which are opposed to each other;
• a membrane circuit board located under the keycap;
• a flexible light shielding element arranged between the keycap and the membrane circuit board, and comprising a bottom layer and plural stopping walls, wherein each of the stopping walls comprises a wall body and a platform part, the wall body is protruded from the bottom layer and in a direction toward the keycap, an included angle is formed between the wall body and the bottom layer, the platform part is protruded from the wall body, the platform part is arranged between the second end surface of the keycap and the bottom layer, and the platform part is contacted with the second end surface of the keycap, wherein the bottom layer and the plural stopping walls of the flexible light shielding element are integrally formed as a one-piece structure;
• a supporting plate located under membrane circuit board;
• and
• a backlight module located under the supporting plate, wherein the supporting plate is arranged between the backlight module and the membrane circuit board, and the backlight module comprises a light guide plate and a light-emitting element located beside the light guide plate, wherein the platform parts of the plural stopping walls are included in an orthographic projection region of the keycap with respect to the bottom layer, and the wall bodies of the plural stopping walls are located outside the orthographic projection region, so that the light beam emitted by the light-emitting element is confined to the orthographic projection region of the keycap and the region of the keyboard device outside the orthographic projection region of the key structure is not illuminated.