Fujitsu Corporation

Hitachi Maxell, Limited

Fujitsu Hitachi Plasma Display Limited

Shigeki Kameyama

Tomokatsu Kishi

Tadatsugu Hirose

Hirohito Kuriyama

Shigetoshi Tomio

Takahiro Takamori

Keiichi Kaneko

Akira Yamamoto

Yoshikazu Kanazawa

Toshio Ueda

Kazuo Yoshikawa

Akihiro Takagi

Akira Otsuka

Tetsuya Sakamoto

Ayahito Kojima

Rikurou Tanahashi

Noriaki Setoguchi

Masaya Tajima

Kyoji Kariya

Keishin Nagaoka

Yoshimasa Awata

Shinpei Yao

A display apparatus, that can prevent thermal destruction and burning with a simple structure, has been disclosed. In the apparatus it is judged that there is possibility of a pattern, whose area with high brightness is small, being displayed frequently, when a state in which the total light emission pulse number remains large occurs with high frequency, and if such a state is detected, the total light emission pulse number (sustain frequency) is reduced to prevent the thermal destruction and burning.

Display apparatus

A plasma display panel comprising plural kinds of phosphors, each of which emits a light having a different kind of color, separators which separate the plural kinds of phosphors, and discharge cells having sustain electrode pairs which create discharges producing the light emissions from the phosphors. In the plasma display panel, sustain discharge currents through the sustain electrode pairs in the discharge cells are set at different values according to respective brightness of the lights emitted from the plural kinds of phosphors.

Plasma display panel

A plasma display panel having a high power efficiency by reducing parasitic capacitances comprises first and second substrates disposed facing each other, a plurality of address lines formed on the first substrate and extending along a first direction and a plurality of X and Y electrodes formed on the second substrate and extending along a second direction crossing the first direction. A first dielectric layer covers the X and Y electrodes formed on the second substrate, the first dielectric layer having a dielectric constant higher than a dielectric constant of the second substrate, and a trench formed at least through the first dielectric layer in an area between two adjacent X and Y electrodes, the trench extending along the second direction. Alternatively, a plurality of projections extends along the second direction, crossing the first direction, a plurality of X and Y electrodes being formed on the second substrate along the projections, the X and Y electrodes, respectively, being formed in opposite side areas of each projection, and a dielectric layer covering each of the X and Y electrodes and formed in the opposite side areas of each projection on the second substrate, the dielectric layer having a dielectric constant higher than a dielectric constant of the second substrate.

Plasma display panel with reduced parasitic capacitance

A method for driving a plasma display panel applies, within a subfield among the n subfields, a narrow-width pulse having a pulse width equal to or less than 2 &mgr;s to first electrodes in order to cause an erase discharge while terminating a discharge caused between the first and second electrodes, and applies a voltage pulse to third electrodes so that the voltage pulse falls at the same time as the narrow-width pulse falls.

Method and device for driving plasma display

A plasma display panel comprising plural kinds of phosphors, each of which emits a light having a different kind of color, separators which separate the plural kinds of phosphors and discharge cells having sustain electrode pairs which create discharges to create the light emissions from the phosphors. In the plasma display panel, a sustain discharge current through each sustain electrode pair in the discharge cells is set a different value according to a brightness of each light emitted from the plural kinds of phosphors.

A display for performing gray-scale display according to a subfield method, in which the frame memory area is minimized, has been disclosed. The display comprises: a main unit including a video signal source and a display interface having a frame memory; a display panel unit including a matrix panel for performing gray-scale display according to the subfield method, a driver for driving the matrix panel, and a display control unit for receiving display signals from the display interface in the main unit and controlling the driver according to the display signals; and a cable for linking the main unit and display panel unit. The display interface transmits display signals covering one frame in units of a subfield. This obviates the necessity of a frame memory that is employed in a known display adopting a CRT interface as an interface between the main unit and display panel unit and that is used to convert display signals adapted to the CRT interface into those adapted to the subfield method.

Display for performing gray-scale display according to subfield method,

In a plasma display panel, an analogue brightness value given by a variable resistor is periodically converted into a digital brightness value and stored in a memory. A digital brightness value of a current period is compared with the digital brightness value of the next preceding period stored in the memory, to produce a difference brightness value which is compared with a predetermined brightness value and, if larger than the predetermined value, the brightness value stored in the memory is updated. Alternatively, power consumption of a display device is detected and, when the power consumption is larger than a set point, a brightness value is gradually decreased and, when the power consumption is smaller than the set point, the brightness value is gradually adjusted to a brightness set value.

Brightness control and power control of display device

A power supply which inputs a first direct-current voltage from the outside and outputs a high direct-current voltage to a plasma display panel. The power supply connects the input direct-current voltage to a positive polarity side of a first capacitor of a plurality of N capacitors connected in series to each other and connects a negative polarity side of the first capacitor to a ground (step 1); connects the input direct-current voltage to a positive polarity side of an Mth capacitor of the N capacitors and connects a negative polarity side of the Mth capacitor to the ground (step 2); repeats step 2 for M=2 to N (step 3); and outputs a voltage of the positive polarity side of the first capacitor to the plasma display panel (step 4).

Power supplying apparatus, a plasma display unit, a method of converting

A triple-electrode planar display capable of achieving further power saving has been disclosed. A drive unit is dedicated to a planar display having a display panel in which cells being arranged in the form of a matrix and having a memory function and discharge glow function are formed, in which one of each pair of electrodes on the same substrate which are responsible for discharge glow is a common electrode connected in common. The drive unit includes a common electrode drive circuit for applying an alternating voltage to the common electrode, and a power save circuit that when the common electrode is changed from a high potential to a low potential, restores and accumulates power applied to the common electrode, and that when the common electrode is changed from the high potential to the low potential, applies accumulated power to the common electrode. The power save circuit includes a restoration channel that includes a capacitive element and inductance element and that restores power, and an application channel that includes an inductance element and that applies accumulated power to the common electrode.

Drive unit for planar display

A flat panel display has a low withstand voltage and performs high speed line sequential scanning and recovers power. An AC type panel display has electrodes arranged in a matrix form, a push-pull type driver circuit, having first and second transistors, provided for each pair of plural pairs, of power supply lines connected to a driver circuit for driving a plurality of display electrodes to be scanned and a power supply which supplies a defined voltage to one of the respective power supply lines of each pair connected to the corresponding driver circuit, and a leakage control switch which leaks the defined voltage applied to the power supply line.

Driver for flat display panel

When a MOS transformer switch 14 shifts from an ON state to an OFF state, a fly-back spike voltage is induced from a secondary winding 122 to a primary winding 121. As a result electric charge accumulates in a capacitor 281, via a diode 283 and a voltage, i.e. is the voltage of a battery 10 on to which the voltage between terminals of the capacitor 281 is stacked, is supplied to the DC power-supply voltage input terminal Vcc of a control circuit 16 via a LC low pass filter 34A. Energy stored in the capacitor 281 may be effectively utilized, while the fly-back spike voltage to the control circuit 16 side is cut by a LC low pass filter 34A.

Growing community of inventors

Kawasaki, Japan

Shigeki Kameyama