Patent ID: 7091947

Claim:
An apparatus for prolonging lamp lifetime by reducing unneeded luminance of at least one lamp in phases, the apparatus comprising a scaler for receiving image signals, and a Microprogrammed Control Unit (MCU) for detecting in real time statuses of image signals being input to the scaler, wherein: the MCU comprises: a timer for recording an elapsed time during which no image signal is input to the scaler; a memory for storing a plurality of preset times and preset percentages, wherein each preset percentage corresponds to a respective preset time and indicates a ratio of a corresponding reduced luminance to a normal luminance of a lamp; and a Central Processing Unit (CPU) for comparing the elapsed time recorded by the timer with the preset times, and generating various control signals according to various comparison results; and the sealer generates Pulse Width Modulation (PWM) waves with duty cycles according to the control signals of the CPU, the PWM waves being used for adjusting the luminance of said lamp.