Hitachi, Ltd.

Hitachi Keiyo Engineering Co., Ltd.

Kinuyo Hagimae

Atsushi Yoshida

Seiji Hata

Toshio Asano

Kazuo Majima

Jun Mochizuki

Daisuke Katsuta

Masao Taniguchi

Teruo Matsuo

Souichi Yano

An apparatus for identifying positions of pixel defects on a display screen, such as a cathode-ray tube or a liquid crystal display, operates to pick up an image signal of a display screen representing a predetermined image with an imaging camera, shift the image signal of the imaging camera by one pixel in one and another directions with respect to the display screen, and obtain a difference of a signal level between a defective portion and a normal portion on the screen, based on the signals obtained when the image signal of the imaging camera is shifted in one and another directions. The apparatus also serves to calculate a relative inclination between the imaging camera and the display screen for obtaining a difference of a signal level between a defective portion and a normal portion of each pixel. The results make it possible to clearly identify the difference of the signal level between the defective portion and the normal portion.

Method and apparatus for checking defect on display screen

Character recognition method and system in which a character indicated in a printed, stamped, carved or other form is two-dimensionally imaged and stored as image data and the stored image data is subjected to an image processing to recognize the character. The recognition of the character is performed in such a manner that each time the comparison of plural kinds of feature vectors extracted from the character to be recognized and a dictionary vector of each candidate character in a group of candidate characters preliminarily prepared is made for one of the plural kinds of feature vectors, a candidate character having its dictionary vector away from the extracted feature vector by a distance not smaller than a predetermined value is excluded from the candidate character group. The dictionary vector for each candidate character is defined as an average vector for a variety of fonts. A difference between the dictionary vector and the feature vector extracted from the character to be recognized is estimated by virtue of a deviation vector for the variety of fonts to produce an estimated value. The exclusion from the candidate character group is judged on the basis of the estimated values each of which is cumulatively produced each time the estimation for the difference is made.

Character recognition method and system

Growing community of inventors

Yokohama, Japan

Kinuyo Hagimae