Canon Kabushiki Kaisha

Kabushiki Kaisha Toshiba

Kazuhiko Murayama

Aoji Isono

Kenji Shino

Tadashi Aoki

Hideo Mori

Atsushi Mizutome

Tomoyuki Ohno

Akio Yoshida

Takashi Yamamoto

Yasuhiko Sano

Kazunori Katakura

Kenzo Ina

Osamu Sagano

Tatsuro Yamazaki

Toshimichi Ouchi

Tsutomu Sakamoto

A method is provided to control an image display apparatus having a display panel in which a plurality of display devices are arranged in matrix with a plurality of column wires and a plurality of row wires. The method includes the steps of outputting a selection electric potential to a row wire to be driven, and generating a modulated pulse based on image data and outputting the modulated pulse to the column wires.

Method of controlling an image display apparatus

A scanning circuit and an image display device in which the influence of losses in a signal path to scanning wiring and a scanning signal output circuit can be reduced. By considering matrix drive in which one row is driven at a time and two or more of the rows are not simultaneously driven, the 480 rows are divided into six modules and one feedback circuit is provided in correspondence with each module to perform feedback control of the output buffers corresponding to 80 rows. An output from a switch is amplified by an operational amplifier and is input as a compensation signal to all the output buffers by an output voltage compensation circuit. Compensation for a voltage drop is made by using the compensation signal for an increase in voltage such that the apparent voltage drop due to the output current is limited to a small value.

Scanning circuit and image display device

The present invention discloses an invention about a drive waveform for driving an image display unit. In particular, the present invention discloses the structure of using as a drive waveform a drive waveform signal which is level controlled by a plural of discontinuous levels including a minimum level which is a level corresponding to luminance brightness gradation data which is not 0, at least one non-minimum level which is a level corresponding to larger luminance brightness gradation data, and an intermediate level between the above-described minimum level and the above-described non-minimum level, and is given pulse width control with discontinuous pulse width, and which has a portion, which is controlled with the above-described minimum level, in its trailing edge, and a portion, which is controlled with the above-described intermediate level just before the former portion, when it has the portion controlled by the above-described non-minimum level.

Drive circuit, display device, and driving method

A modulation circuit that outputs modulation signals, comprising: a memory circuit that stores waveform data that determines the time width of a portion of a modulation signal, the portion being adjusted to a predetermined amplitude value, the waveform data being stored in such a manner as to output a plurality of modulation signals; and a circuit that generates the modulation signals, based on the waveform data and input gradation data.

Modulation circuit, driving circuit and output method

The present invention can provide a driving apparatus capable of compensating an influence of a voltage drop at low costs in a simple manner, which includes: a column driver circuit that generates at least one of modulation signals different in start reference time in one horizontal scanning period and the modulation signals obtained by using pulse width modulation and voltage amplitude modulation in combination; and a correction circuit that corrects a voltage of the row selection signal so as to suppress a voltage variation of the row selection signal, which is caused due to at least a resistance of an output stage of the row driver circuit and a current caused to flow into the resistance.

Driving apparatus, driver circuit, and image display apparatus

An image display apparatus having a plurality of image forming devices. In an output circuit provided between constant voltage supplies and wiring for driving each of the image forming devices, MOSFETs are successively turned on from the one having a higher ON resistance at the time of switching to make a stepwise transition between outputs from the constant voltage supplies, and have steady potential, thereby limiting undesirable variation in signal potential at the time of switching.

Image display apparatus

A modulator includes a modulation circuit for generating modulation signals based on inputted luminance data and for outputting the modulation signals to a plurality of image display elements, each of which is driven by a potential difference between a selection potential applied within a predetermined time period by a selection circuit and the modulation signal. The modulation signal has a waveform which is a combination of a plurality of unit pulses, with the unit pulses having an identical width and n kinds of peak values A1 to An, with n being an integer greater than 1, and A1&#x3c;. . . &#x3c;An. Additionally, the unit pulses are combined in such a way that maximal peak value portions of the waveform of the modulation signal are dispersed, and that a rising portion and a falling portion of the waveform have a stair-step-like shape.

Driving device and image display apparatus

A drive waveform signal which is level controlled by discontinuous levels including a minimum level corresponding to luminance brightness gradation data which is not 0, at least one non-minimum level corresponding to larger luminance brightness gradation data, and an intermediate level between the minimum and non-minimum level. The signal, which is employed to drive an image display unit, is given pulse width control with discontinuous pulse width, and has a portion, controlled with the minimum level, in its trailing edge, and a portion, controlled with the intermediate level just before the former portion, when it has the portion controlled by the non-minimum level.

A drive signal generation circuit which performs gradation control on a load by a drive signal having a stepped waveform. In a case where the wave height value corresponding to input gradation data is Vm (2&#x2266;m&#x2266;n), the drive signal is caused to rise in such a manner that each output Vk (2&#x2266;k&#x2266;m) is produced one slot after the output V(k&#x2212;1) to increase the wave height value V(reference potential) to Vm in a stepping manner. One slot corresponds to a unit time of the pulse width modulation. The drive signal is caused to fall in such a manner that each output V(k&#x2212;1) (1&#x2266;k&#x2266;m&#x2212;1) is produced one or two slots after the output Vk to reduce the wave height value from Vm to off level in a stepping manner. A delay circuit is used to delay signals slot by slot. A selection is made from delayed signals according to luminance data to determine a waveform. The circuit is also designed to enable the drive signal waveform rise position to be changed.

Drive signal generator and image display apparatus

A display control apparatus and a display apparatus respectively include control units for controlling themselves. The display control apparatus reads or writes data in a memory that can be accessed by the control unit in the display apparatus. Accesses from the display control apparatus to the memory in the display apparatus are made via a bus arranged in addition to a display image data transfer bus.

Display apparatus, display system, and display control method

A data transfer method transfers data to an information-side driver for driving a display apparatus. Wherein, driver circuits each comprise a chip address/video data discrimination circuit and a unit driver are mounted around the display apparatus. A unique chip address is set for each of the unit drivers by a hardware pattern. Data exchange with the driver circuits is performed so that chip address information and video data information are time-divisionally transferred to the target unit driver using a chip address/video data common bus line and a chip address/video data discrimination control signal.

Data transfer method, display driving circuit using the method, and image display apparatus

A display control apparatus receives display data from a display information supply apparatus such as a personal computer, performs predetermined processing of the display data, and transfers the processed data to a display apparatus via a high-speed display image transfer bus so as to display the display data on the display apparatus. When the display information supply apparatus issues a predetermined instruction, the display control apparatus outputs corresponding instruction information to the display apparatus via a second bus arranged in addition to the high-speed bus so as to display the display data in a mode corresponding to the contents of the instruction.

Growing community of inventors

Kanagawa, Japan

Kazuhiko Murayama