Quantum dot backlights for use in displays and processes for controlling the dimming of quantum dot backlights are provided. The backlight can include an LED (e.g., a blue LED) configured to emit a light through a sheet of quantum dots. The quantum dots can be configured to emit colored light (e.g., red and green light) in response to the light emitted from the LED. To control the relative luminance of the LED, the backlight can be controlled through the use of current dimming to adjust the brightness of the LED at high relative luminance settings to increase the light output efficiency and can include the use of pulse width modulation to adjust the brightness of the LED at low relative luminance settings to reduce the amount of wavelength shift experienced by the LED.