A display device includes a display module, a light source module and a guiding optical film. The display module includes a first substrate, a second substrate and a display medium. The light source module generates directional light. The display module has a vertical electric field. The display medium is optically isotropic, and the display medium is optically anisotropic when driven by the vertical electric field. The directional light is not perpendicular to the first substrate when the directional light enters the display nodule. The directional light is not perpendicular to the second substrate when the directional light exits the display module. The guiding optical film is disposed on the second substrate and has a light incident surface and a light emitting surface. After the directional light exits the guiding optical film, emitting light is formed, and the emitting light and the light emitting surface has an included angle there between.