Mitsubishi Electric Corporation

Advanced Display, Inc.

Hisaharu Oura

Hironori Takaoka

Susumu Shibata

Tetsuya Ikemoto

Shingo Nagano

Yuichi Masutani

A liquid crystal display apparatus according to the invention is an in-plane switching liquid crystal display apparatus having gate wirings and source wirings, which intersect one another, and also having pixel electrodes each connected to an associated one of the source wirings, and common electrodes disposed opposite to the pixel electrodes. A scanning signal is inputted to the gate wiring so that one horizontal period has a writing period, in which a pixel potential is written to the pixel electrode, and a nonwriting period, in which no pixel potential is written to the pixel electrode. The pixel potential is outputted to the source wiring in the writing period, while a common potential is inputted to the source wiring in the nonwriting period.

Liquid crystal display apparatus and method for generating a driver signal based on resistance ratios

The present invention provides an image processing circuit capable of properly determining whether or not image data is a static image or a moving image and performing overdrive processing thereon. The image processing circuit includes a quantization unit (quantization/threshold-value proximity determination circuit) for quantizing image data input to a liquid crystal display with a predetermined threshold value and outputting the quantized data, a threshold-value proximity determination unit (quantization/threshold-value proximity determination circuit) for determining whether or not the image data is proximal to the threshold value and outputting threshold-value proximity determination data, a moving-image/static-image determination unit (moving-image/static-image determination circuit) for determining whether or not the image data of a current frame is a static image or a moving image, on the basis of the quantized data and the threshold-value proximity determination data of the current frame and the quantized data and the threshold-value proximity determination data of the previous frame, and an overdrive processing unit (LUT, moving-image/static-image processing circuit) for outputting the image data which has been subjected to overdrive processing if the moving-image/static-image determination unit determines that the image data is a moving image.

Image processing circuit

The present invention provides an image processing circuit capable of sufficiently correcting a temperature characteristic of a response speed, varying depending on gray-scale, of a liquid crystal display, while suppressing an increase in circuit scale. The present invention provides an image processing circuit for a liquid crystal display performing overdrive processing and the image processing circuit includes a overdrive LUTfor outputting an overdrive calculation value, based on image data of a previous frame and image data of a current frame, a plurality of temperature correction LUTseach outputting a correction value for use in temperature correction of the overdrive calculation value, a temperature correction LUT selection circuitfor selecting one of the temperature correction LUTsbased on temperature data, and a correction calculation circuitfor calculating an overdrive output value based on the overdrive calculation value output from the overdrive LUTand the correction value output from the temperature correction LUTselected by the selection circuit

The present invention provides an image processing circuit capable of performing overdrive processing on all gray-scale while suppressing the degradation of the contrast of a liquid crystal display. According to the present invention, an image processing circuit for a liquid crystal display performing overdrive processing includes a data compression circuit for compressing the gray-scale of image data in the direction of medium gray-scale with a predetermined data compression ratio and outputting compressed data, an FRC processing circuit for performing pseudo-gray-scale processing on the compressed data and outputting pseudo-gray-scale image data having the same number of gray-scale as the number of gray-scale of the image data and an overdrive processing circuit for setting the voltage difference between the highest gray-scale and the lowest gray-scale of the pseudo-gray-scale image data to be greater than the voltage difference between the highest gray-scale and the lowest gray-scale of the compressed data, assigning a new voltage in the region of the gray-scale difference between the image data and the compressed data and utilizing the new voltage for overdriving processing.

Image processing circuit and image processing method

A liquid crystal display according to the present invention can prevent interference fringe on a display panel due to a switching noise of a DC/DC converter, therefore a high-quality image can be displayed. Either of input signals for a timing control circuit is also supplied to a PLL circuit and the DC/DC converter is controlled by an output signal of the PLL circuit, thereby enables to synchronize a switching frequency of the DC/DC converter and control signal.

Liquid crystal display

The inverter for multi-tube type backlight includes two step-up transformers of one-side grounded type, wherein the two step-up tranformers respectively output electric power to one or a plurality of cold cathode tubes, and wherein outputs of the two step-up tranformers are of identical frequency but of mutually reversed phases.

Growing community of inventors

Kumamoto, Japan

Hisaharu Oura