Abstract: Devices are provided for using ambient light to illuminate transmissive displays. One such backlight includes a light source configured to provide artificial light to the transmissive display when the backlight is closed and a surface configured to reflect ambient light to the transmissive display when the backlight is open. Another backlight includes a surface configured to provide ambient light to the transmissive display even when the backlight is closed. In some implementations, power to the light source may be reduced or shut off when the backlight is open and/or when sufficient ambient light is being provided to the transmissive display.