Sony Corporation

Panasonic Corporation

Mitsubishi Electric Corporation

Shigeru Takasu

Motosuke Irie

Hisao Koga

Takehiro Sugita

Koji Ikeda

Akio Kurobe

Yuji Igata

Go Kuroda

Satoru Suzuki

Hirotoshi Yamada

Hiromu Okamoto

Junichi Ohshima

Yoshinori Mizugai

Manabu Suzuki

Motoki Ouchiyama

Kazuo Kii

Toshinori Hamada

A communication device includes a data communication unit that sends a communication signal, which is obtained by at least modulating transmission data, to a power line; a zero-crossing-point detector that detects a zero crossing point of an alternating voltage applied from the power line; a transmission unit that sends a coexistence signal to the power line in a coexistence region that starts at a time based on the zero crossing point, the coexistence signal having information for allowing systems to be present on the power line; a receiving unit that detects the coexistence signal from the power line in the coexistence region; a setting unit that sets a detection period for performing a detection operation for detecting a broadcast wave in accordance with the coexistence signal; and a broadcast-wave detector that detects a broadcast wave by performing frequency analysis on a signal on the power line in the detection period.

Communication device and method for detecting broadcast wave to be performed by communication device

A communication apparatus which may include a power supply that acquires a supply voltage from a power line connected from outside, a transmission control unit that transmits a pilot signal and signals subsequent to the pilot signal to the power line, a pilot signal detection unit that detects pilot signals transmitted to the power line by other apparatuses, and a timing adjustment unit that adjusts transmission timing of the pilot signal of the communication apparatus in accordance with that of the pilot signals transmitted by the other apparatuses.

Communication apparatus and transmission line communication chip for adjusting transmission timing

A communications device, which performs data communication, includes an AC cycle sensorwhich is connected to a power linesupplied with an a.c. voltage and generates a synchronous signal SS at timing of an a.c. voltage waveform AC of the power line; a data communicatorfor performing data communication; and a communications controllerwhich performs communication of a control signal including information showing at least one of a communications device and a communications standard and controls the data communicator. When the a.c. voltage supplied to the power lineis an N-phase and when the cycle of the a.c. voltage waveform is T, data communication to be performed in a communication period subsequent to the period is controlled on the basis of the control signal included in the period of T/2M on condition that M is a natural multiple of N.

Communications device and communications method

An image display device well suited for a multi-scanning type monitor includes a video signal measurement circuit that detects a horizontal synchronization frequency fH and a vertical synchronization frequency fV from an input image signal that conforms to the GTF Standard. A main control portion calculates timing data relative to a waveform of the signal () using the frequencies fH and fV, calculates adjustment parameters for adjusting a size and a position using this timing data, and sets the adjustment parameters to deflection control circuits, so that an image of the image signal may be displayed well on a CRT. Since the timing data is calculated using the synchronization frequencies fH and fV of the input image signal, it is possible to save on a memory capacity without storing timing data that corresponds to a plurality of different kinds of image signals.

Video display apparatus and video display method

A display apparatus connected to a personal computer for carrying out character display or graphic display in accordance with information from the personal computer, which is installed with a power saving button for instructing a shift to a power saving mode for reducing power consumption and a micro controller for determining input of the power saving button and controlling a power supply, a deflection circuit and an image circuit to shift to the power saving mode.

Display apparatus having a power saving mode

A timing data table in which timing data is registered for respective types of video signals defined by frequency and polarity of a respective synchronizing signal is provided in a nonvolatile memory. A main control part retrieves the timing data table with the type of the video signal as a retrieval key to acquire pertinent timing data, and, using this timing data, necessary adjustment parameters (that is, horizontal position adjustment parameter, horizontal size adjustment parameter, vertical position adjustment parameter and vertical size adjustment parameter) are calculated by operations and outputted to a horizontal deflection control circuit and to a vertical deflection control circuit. Thereby, a video display apparatus and a video display method capable of reducing time required to make adjustments and performing correct and highly responsive video display regardless of the types of video signals are provided.

The size of an image displayed on a tube surface is varied while maintaining the aspect ratio thereof at a constant. First, if there is information of an arbitrary horizontal-size variable parameter and a vertical-size variable parameter because of parameters supplied previously by adjustments, the horizontal/vertical size of a raster formed at that time can be obtained, and the aspect ratio thereof can be obtained on the basis of the horizontal/vertical size of the raster. Then, during a zoom mode, the vertical-size variable parameter corresponding to the updated horizontal-size variable parameter is computed so that the detected aspect ratio becomes constant, and the raster size is changed in accordance with these values.

Image-size varying apparatus, image-size varying method, and monitor apparatus

A high-voltage generating circuit for use in a CRT display apparatus has a horizontal drive circuit which is supplied with a horizontal frequency signal synchronous with a horizontal synchronizing signal in an input signal, a high-voltage converter output circuit which can be turned on and off by an output signal from the horizontal drive circuit, and a flyback transformer connected to an output terminal of the high-voltage converter output circuit. A frequency multiplier connected between the horizontal drive circuit and a terminal supplying the horizontal frequency signal to the horizontal drive circuit multiples the frequency of the horizontal signal at the terminal by a multiplication factor variable depending on the frequency of the horizontal frequency signal.

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Tokyo, Japan

Shigeru Takasu