Sharp Kabushiki Kaisha Corporation

Motoyuki Oniki

Tomoyuki Ichiza

Masahiro Ide

Kohji Iwasaki

Provided is a liquid crystal display device capable of improving motion blur and preventing excessive current flow into a light source with a desired balance in a structure where the light intensity of a backlight device is properly changed in conjunction with the ambient illuminance. If the ambient illuminance (S) of a liquid crystal display device is lower than a preliminarily set predetermined illuminance, a backlight scanning process (intermittent lighting process) is implemented (Yes of S, S), while if the ambient illuminance is not lower than the predetermined illuminance, the backlight scanning process (intermittent lighting process) is terminated (No of S, S). The light intensity of the backlight device is changed in conjunction with the high and low ambient illuminance by changing the drive current supplied to the light source, depending on the ambient illuminance of the liquid crystal display device and whether or not to implement the backlight scanning process (intermittent lighting process) (S, S).

Liquid crystal display device and TV receiver

Provided are an LED control device and a liquid crystal display apparatus, wherein energy loss or noise (humming sound) to be generated upon switching the control of power supplying from a power supply device to a plurality of LED groups, between constant current control and constant voltage control, can be alleviated. In a configuration wherein power to be supplied from one power supply device, to which a plurality of LED groups are connected in parallel, is controlled with constant current control wherein the voltage at the end section at the cathode side of the LED group to be turned on is to be maintained at a predetermined first voltage value, when at least one of the LED groups is to be turned on, and controlled with constant voltage control wherein the voltage at the end sections at the anode side of the LED groups is to be maintained at a predetermined second voltage value, when all the LED groups are to be turned off, a phase difference of 2&#x3c0;/n (n is the number of LED groups) is made to be generated between PWM signals corresponding to each of the LED groups.

LED control device and liquid crystal display apparatus

To provide a liquid crystal display device capable of reducing the occurrence of a multi-contour in the display of a moving image to the minimum, the cycle of execution of an intermittent lighting operation in backlight scanning and the cycle of a vertical synchronization signal are made equal when an interpolation image insertion mode in which an interpolation image signal generated on the basis of two or more continuous frame images is inserted between frames and written into a liquid crystal panel is executed, and the cycle of the execution of the intermittent lighting operation in the backlight scanning is made longer than the cycle of the vertical synchronization signal (or the backlight scanning is disabled) when an overlapped image output mode in which the same frame image is written into the liquid crystal panel continuously n times is executed.

Liquid crystal display device having multi-speed drive modes and image interpolation

In an LCD device, picture quality luminance is controlled through the combination of pulse-width modulation (PWM) system and current value control system, reducing the electrical power consumption associated with turning on an LED. In the LED backlight, the light emitting luminance of the LED is controlled by both PWM and also by current value control, which selects the value of the current supplied to the LED from a plurality of set values. At least one of the plurality of set values is a predetermined current value at which duty reaches a maximum value at the maximum luminance value used in a specified picture quality mode of the picture quality modes established in the liquid crystal display device. In the aforementioned specified picture quality mode, the greatest luminance value to be used is smaller than at least the greatest luminance value used in other specified picture quality modes.

Growing community of inventors

Osaka, Japan

Motoyuki Oniki