Patent ID: 6429839
Filing Date: 2002-08-06
Classification: G09G

Abstract:
A liquid crystal display apparatus, comprising:a liquid crystal display device; a light source for illuminating the liquid crystal display device; a LCD device driving circuit for providing a driving voltage to the liquid crystal display device based on a display data signal and a plurality of liquid crystal driving signals including a display data latch signal; a dividing circuit for dividing a frequency of the display data latch signal by a factor of N so as to obtain a period which is N times as large as that of the display data latch signal, where N is an integer greater than zero; a duty control circuit for changing an ON duty ratio of the frequency-divided signal by using the frequency-divided signal as a reference frequency; and a light source driving circuit for turning the light source ON/OFF based on a signal from the duty control circuit having the ON duty ratio set in the duty control circuit, wherein where a driving duty ratio is (1/D), and a remainder of D divided by the integer N is A, each of the integer N and the value D is set to an integer greater than zero which satisfies the following expression: âˆ’1&lE;{(N/A)âˆ’2}&lE;1.