Fujitsu Corporation

Fujitsu Display Technologies Corporation

Yoshiya Kaneko

Seiichi Iwasa

Tsutomu Kai

Kengo Nogiwa

Tetsuya Kobayashi

Hisashi Yamaguchi

Hiroshi Murakami

Kazuhiro Takahara

Munehiro Haraguchi

Takayuki Hoshiya

Hiroyuki Isogai

An LCD apparatus has a control circuit which makes a timing of the rear edges of scanning pulses provided to predetermined scanning lines coincide with the time when the display potential is renewed, wherein each of the predetermined scanning lines corresponds to an addition of a picture line to a picture or a reduction from two picture lines to one picture line on a picture in order to compensate for a difference between the number of scanning lines of the LCD and the number of lines of the picture to be displayed. In the control circuit, a circuit detects cycle times of the vertical and horizontal sync pulses, an MPU determines the reference value REF on the basis of the detected value and count CH of the horizontal sync pulse *HS from a counter, and a circuit generates a signal AE which makes the time when the pulse count CD of pixel clock CLKD from the counter becomes equal to the REF that coincides with the timing of the rear edge of scanning pulse.

Method and apparatus for driving liquid crystal display panel

A display device includes a display unit of a dot-matrix type, each pixel of which has view-angle-dependent characteristics. The display device further includes a correction circuit which corrects the view-angle-dependent characteristics by changing a voltage of a video signal with respect to every at least one horizontal scan period.

Correction of view-angle-dependent characteristics for display device

In a driver circuit of direct drive matrix type LCD panel, a quantity of ON-STATE cells (or OFF-STATE cells) displayed on the just previous scan electrode is counted and a quantity of ON-STATE cells (or OFF-STATE cells) to be displayed on a present scan electrode is also counted. A compensation voltage is generated according to a predetermined relation based on a difference of the two above-counted quantities, and is superposed onto drive voltages of unselected scan electrodes or of each of data electrodes, in a polarity that an undesirable spike voltage induced on unselected cell voltage is cancelled, in synchronization with selection of the present scan electrode. The compensation voltage may be generated according to a digital difference of the two quantities or to a change in an analog voltage representing the counted quantity. The above-described relation of the compensation voltage versus the counted quantity difference may be proportional or may be given with a predetermined specific relation to meet the panel characteristics. The compensation voltage may be a flat voltage during the period for selecting the single scan electrode or may be of a spike waveform. Amplitude of this spike is determined by the above-described predetermined relation. An irregular panel brightness caused from spike voltages induced from data electrode voltage application is cancelled.

Method and apparatus for driving a liquid crystal display panel

A magnetic bubble memory device with major/minor loops includes at least one boot loop and a plurality of minor loops. Data stored in the boot loop in the form of bubbles are controlled by the reading out of the data independently from the minor loops. Header data are stored in the boot loop. Faulty loop data of the minor loops are stored in the minor loops with a certain positional relationship based on the header data. This results in allowing the device to be applied to a memory having a larger capacity, a higher production yield, and a high-speed detection time for faulty loop data.

Magnetic bubble memory device

Disclosed herein is a method of testing a magnetic bubble device which guarantees allowable variation ranges for a variety of signal components of input signals applied to a magnetic bubble element when the magnetic bubble device is to be energized. A variety of signal components are varied in a testing cycle for writing, reading and collating information, whereby a plurality of combinations of the variety of signal components are obtained. The obtained input signals are continuously applied to the bubble element to effect the test.

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Kawasaki, Japan

Yoshiya Kaneko