[in Japanese]

View full abstract

A new cellgap measurement method is described for reflective TN-LCD (twisted-nematic liquid crystal displays). We investigated reflected-intensity behavior in cell-gap measurement, which is based on reflective polarization analysis. The surface reflection of the sample was found to have a decisive influence on the obtained cellgap value and was taken into account in the new method. The method showed good agreement with a trans-missive cellgap measurement in an experiment using a trans-missive LC cell and external reflector. We applied it to microscopic cellgap mapping using a microscope and a CCD camera system. The obtained map is consistent with the shape of the internal reflector.

View full abstract

Various motional artifacts appear on PDP images Also a gray scale capability at low luminance levels is not satisfactory These problems can be overcome by increasing the number of sub-fields and the field frequency This paper introduces a driving method with which 900cd/m² luminance and 600 : 1 dark room contrast were achieved by applying only one reset pulse per TV field An expression of 54 randomly addressable subfields on an AC-PDP was made possible by adopting a 3-phase sustain pulse technique combined with an Address-While-Display drive scheme The technique provided a sixfold increase in field frequency to 360Hz compared to the conventional frequency of 60Hz It was proven by using a 42″ PDP that blurring of moving images was reduced significantly.

View full abstract

A 16cm, ∅29.1mm compatible projection CRT, integrated component system has been developed utilizing an LD-Hi-UPF electron gun with an effective focusing lens of 21mm. This was achieved with a dual diameter neck (∅29.1-36.5mm) integrated component design. The current ∅29.1mm projection CRT deflection power was maintained while reducing the 5% center beam spot profile size by 20% (2mA optimum focus). The integrated components were optimized to provide the system with improved corner focus. This CRT delivers superior image quality and is compatible with current ∅29.1mm neck CRTs in rear projection systems.

View full abstract

Picture quality and readability of thirteen LCDs for mobile telephones were subjectively assessed by thirty subjects under indoor and outdoor lighting conditions. The luminance, contrast, color gamut, and character and pixel sizes of the LCDs were measured under both lighting conditions. From these results, we investigated the requirements for mobile LCDs in terms of picture quality and readability. Results indicate that the optimum luminance level under a screen illuminance of 200 lx is 50 cd/m², and that the level is 160cd/m² under a screen illuminance of 10, 000 lx. The optimum character size is 3.14 mm heigh, and the optimum stroke width is 0.26 mm.

View full abstract

[in Japanese]

View full abstract

As the popularity of three-dimensional (3D) geometric models has increased, so too has interest in methods to search 3D models based on their shape similarity. Two of the most difficult problems in finding shape similarity between 3D geometric models are a feature vector that succinctly describes the shape of the model and a method to compute the distance between a pair of feature vectors that reflects user preferences. We describe a human-directed 3D shape similarity search method that reflects, to some extent, the user preferences by using a learning classifier. Given an example 3D mesh model, the system first retrieves, as an initial guess, a set of models that are similar to the query based only on an unbiased mechanical measure of the distance (i.e., the Manhattan distance) between a set of feature vectors. The user then iteratively refines the query by tagging a subset of the retrieved models as being either similar or dissimilar. The system learns the user's preference using a learning classifier support vector machine (SVM), so that the distance values between the set of feature vectors are altered to reflect these preferences. Experimental results show that our method is capable of retrieving 3D models that better reflect the preferences of the user than the simple method using only the Manhattan distance.

View full abstract

In dealing with digital terrestrial television broadcasting systems using OFDM, a spectrum measurement is usually used to check the extent of a transmitting amplifier's non-linearity effect. However, capturing both input and output signals and measuring the difference between them are necessary to identify the non-linear characteristics. A new technique to identify non-linear characteristics of an amplifier, which is assumed to follow the AM-AM / AM-PM conversion model, is described. Non-linear characteristics can be measured using this technique with only the output signal of an amplifier working during actual broadcasting. The process requires no special signals. An undistorted (input) signal is estimated using the conventional demodulating process. The characteristics of the two amplifiers were measured, and the results were compared with those of another identification technique. The characteristics derived from the two techniques were found to agree.

View full abstract

A new CMOS image sensor featuring logarithmic conversion is described. The sensor has 654 (H) × 494 (V) pixels, and the cell size is 8μm (H) ×8μm (V). We previously developed logarithmic conversion CMOS image sensors with either an FPN cancellation circuit or an integration circuit. This one has both. The sensor shows clear images without FPN and without flicker noise in brightness fluctuation. Furthermore, the afterimage level was reduced by a new pixel driving method.

View full abstract

[in Japanese]

View full abstract

[in Japanese]

View full abstract