Abstract: A method for adjusting the brightness of an LCD display has the steps of: (a) dividing an adjustable brightness range of the LCD display into three stages, a high brightness stage, a normal brightness stage and a low brightness stage, (b) determining which stage of said three stages has corresponded to a brightness adjust command, (c) adjusting luminance intensity of an LCD panel or luminance intensity of a lamp based on the brightness adjust command. An apparatus for performing the method has a microprocessor to receive the brightness adjust command, a PWM unit coupled to the microprocessor to adjust the current intensity of the lamp, and a voltage level controller coupled to the microprocessor to adjust the voltage level applied on the LCD panel.