Goh Itoh

Novel frame interpolation method for hold-type displays

Flat panel displays (FPDs) such as a liquid crystal display (LCD) and a plasma display (PDP) have a problem of a motion blur. It is known that the motion blur is caused by the hold-type characteristics of LCD. The problem is improved with a double-rate driving method. In this method, it is necessary to insert the middle frame according to the motions by the objects. The middle frame is created using the frame interpolation technique with the motion estimation and the motion compensation. We proposed a robust hybrid method which consists of several kinds of interpolation method and verified that the hybrid method achieved high image quality by the subjective evaluation.

Multi-field driving method for reducing LCD power consumption

We have developed a multi-field driving method for TFT-LCDs in which a displayed image was divided into at least three interlaced sub-field images where visible flicker did not occur as the image refresh rate was decreased. This method made it possible not only to reduce driving-power consumption in the case of still images to less than half, compared to that of conventional methods, but also to ensure that large-area flicker and line flicker were invisible to the human eye.

Equivalent Circuit Model for Thresholdless Antiferroelectric Liquid Crystal Displays

For high quality displays, analog responding liquid crystals with spontaneous polarization need to be coupled with active matrix driving schemes. Our goal is to investigate the possibilities for optimizing liquid crystal materials, thin film transistors, and driving schemes. In this paper, the electrooptical properties of thresholdless antiferroelectric (TLAF) liquid crystal displays (LCDs), which are analog responding, are modeled using an electric circuit which can be applied to conventional simulators. A novel procedure for deducing the circuit parameters on the basis of the experimental results is discussed. It was found that the voltage-dependent capacitance due to the induced spontaneous polarization is important for describing the static and dynamic behavior at different applied voltages. It is shown that our equivalent circuit model reproduces the pixel voltage as well as the transmittance of active-addressed TLAF-LCDs.

Software-processed edge- and level-adaptive overdrive (SELAO) method for high-quality motion pictures

— In this paper, a software-processed edge- and level-adaptive overdrive (SELAO) method, which is a novel overdrive technique that utilizes not only a temporal change of gray levels but also a spatial edge intensity of motion pictures, is proposed. The SELAO method is a software video-processing technology to improve motion-picture quality rendered on LCDs more than is possible with a conventional SLAO method without edge-adaptive overdrive, and it works in real time on commonly used personal computers (PCs).

46.3: Software‐Processed Edge‐ and Level‐Adaptive Overdrive (SELAO) Method for High‐Quality Motion Picture

We have developed the software-processed edge- and level-adaptive overdrive (SELAO) method. The SELAO method is a novel overdrive technique that utilizes not only the temporal change of the gray level but also the spatial edge intensity of the motion picture. The SELAO software can work in real time on PCs. Therefore, the SELAO method can improve the motion picture quality of an LCD more than the conventional SLAO method without edge-adaptive overdrive.

Novel frame interpolation method for high image quality LCDs

Abstract We developed a novel frame interpolation method to interpolate a frame between two successive original frames. Using this method, we are able to apply a double‐rate driving method instead of an impulse driving method where a black frame is inserted between two successive original frames. The double‐rate driving method enables ameliorati on of the motion blur of LCDs caused by the characteristics of human vision without reducing the luminosity of the whole screen. The image quality of the double‐rate driving method was also found to be better than that of an impulse driving method using our motion picture simulator and an actual panel. Our initial model of our frame interpolation method consists of motion estimation with a maximum matching pixel count estimation function, an area segmentation technique, and motion compensation with variable segmentation threshold. Although salt and pepper noise remained in a portion of an object mainly due to inaccuracy of motion estimation, we verified the validity of our method and the possibility of improvement in hold‐type motion blurring.