Matsushita Electric Industrial Co., Ltd.

Keisuke Yamamoto

Minoru Ueda

Mitsuya Masuda

Sadahiro Iyehara

Shizuo Inohara

Namio Yamaguchi

Kazumi Kawashima

Yoshio Yasumoto

Minoru Miyata

Tatsuhiro Hosokawa

Namio Yamaguti

Yukio Furuta

Tsuyoshi Akiyoshi

Masahiro Takeshita

A flat CRT type color image display apparatus comprises a number of horizontally disposed parallel line cathodes, vertical and horizontal deflection means and electron beams control means, wherein a clock pulse signal is produced by frequency-multiplying a pulse signal which is synchronized with color sub-carrier of the color TV signal, chrominance signal is A/D converted using the clock signal, therewith producing a PWM signal with which electron beams are controlled.

Color image display apparatus

The video image display apparatus of flat tube type comprising

Image display apparatus

A flat CRT type image display apparatus comprises a number of horizontally disposed parallel line cathodes and vertical and horizontal deflection means, and electron beams control means, and the deflection means includes digital memory means storing data for deflection signals, address counter means for producing address signal to read out the digital memory means, D/A converters for converting read out data to produce deflection signals and also a microcomputer for setting and adjusting data in the digital memory means.

A flat type color display apparatus includes a phosphor screen and 15 horizontal line cathodes activated in turn from the top one to the bottom one. An electron beam control means and a beam deflection means are provided. Each horizontal line cathode emits a horizontal sheet-shaped electron beam which is vertically deflected in 16 steps, and is divided into 320 rod-shaped electron beams by 320 vertically oblong slits and individually controlled of its intensity by 320 beam-control electrodes. The rod-shaped electron beams are horizontally deflected each selectively impinging R, G and B vertical phosphor stripes in turn. In the operation circuit, R, G and B video signals are sampled and held in R, G and B parts of 320 sample-hold circuits, and stored at one time in 320 memories for respective colors, and time sharingly applied to the respective beam-control electrodes. A color video image is thereby displayed of 240 lines each having 320 picture elements.

A video image display apparatus of the flat tube and multi line cathode type of the present invention includes a phosphor screen, and a predetermined number (e.g. 15) of line cathodes for in-turn emitting a predetermined number of horizontal rows of electron beams. Each row has a second predetermined number (e.g. 320) of rod shaped electron beams for together producing one horizontal line of image on the phosphor screen. A vertical deflection means is provided for vertical deflection of the electron beams in turn at one vertically divided segment corresponding to one of the horizontal rows by means of a vertical deflection signal, e.g. a step wave having a saw-tooth wave envelope. The envelope is adjusted so as to be expanded or compressed or level changed, thereby eliminating any undesirable black horizontal band on the screen due to non-uniformity of electrode construction. A uniform raster is thereby obtainable.

A flat type display apparatus includes an electron beam source for emitting a row of a large number of electron beams, and a phosphor screen having a phosphor layer which emits light in response to impingement by the electron beams. An electron beam convergence means is provided and an electrostatic deflection means for deflecting the electron beams prior to impingement on the phosphor screen. An electron beam controlling means has a number of electron beam controlling electrodes for individually controlling the current of the electron beams to control light emissions from the phosphor screen. A pulse width modulation circuit feeds electron control signals of a constant voltage and pulse-width modulated by video signal information to be displayed. Light emission control without changing converging conditions of electrostatic lenses is thus obtained so that a good linearity between the video signals and the electron beams is obtained.

In the refreshing of the memory contents of the non-volatile memory device, a refreshing buffer memory is provided for temporarily storing a data signal of an address to be refreshed. Not only this data signal is stored in the refreshing buffer memory, but also the address of this data signal and the status of the refreshing processes, that is, up to which step of the refreshing routine the refreshing operation has proceeds, is stored in this refreshing buffer memory. Then, even when the power supply is shut off during the course of the refreshing action, at the next chance of the resumption of the power supply, the refreshing routine can correctly be started from the step at which the refreshing routine was previously terminated, thereby the refreshing operation can always be completed correctly.

Apparatus and method for refreshing non-volatile memory

A channel selection apparatus comprises a counter, a decoder, a clock pulse generator, and a control circuit for controlling them, and selects a channel by switching a channel selection voltage by selecting a potentiometer. The counter includes a cascade-connected flip-flop such that a trailing edge of an AND output of an output of a flip-flop in one stage and a channel selection count input signal triggers a flip-flop in the following stage. The decoder includes a plurality of output transistors and a plurality of parallel-connected transistor sets with common collectors of each of the transistor sets being connected to a base of a corresponding output transistor and input signals being applied to bases of each of the transistor sets.

Channel selection apparatus

An automatic local oscillation frequency control apparatus for a television receiver is disclosed, wherein a video intermediate frequency (VIF) signal is applied to an FM discriminator for generating an AFC voltage through a phase shifter comprised of a serial-parallel resonance circuit, and one of the serial resonance frequency and the parallel resonance frequency of the serial-parallel resonance circuit is selected to be a frequency near a picture carrier frequency while the other is selected to be a frequency which is made by subtracting one half of a differential frequency between the picture carrier frequency and a sound carrier frequency from the picture carrier frequency. The present apparatus can attain an automatic frequency control having a wide pull-in range and a wide hold range.

Automatic frequency control apparatus for television receiver

Disclosed is a device for eliminating the ghost wherein at least two antenna bays are spaced apart in the horizontal direction by 1/4 wavelength, a mixer is provided which mixes the outputs from the antenna bays, phase shifting means for shifting the ghost signal in phase with or out of phase by 180.degree. with the desired signal is inserted between the output terminal of one antenna bay and an input terminal of the mixer, amplitude control means is inserted between the output terminal of the other antenna bay and an input terminal of the mixer, and the output from the mixer is delayed and the delayed output and the undelayed output from the mixer are mixed so as to control their amplitudes and polarities, whereby the ghost signal may be cancelled.

Ghost cancellation device

A ghost signal eliminating system which eliminates a ghost by delaying a video signal through a variable delay line by the delay time of the ghost from the true image and subtracting the delayed video signal from the original video signal. The variable delay line comprises a fine adjusting circuit for fine-adjusting the delay time and a coarse adjusting circuit for coarse-adjusting the delay time, the coarse adjusting circuit being controlled by a detection voltage for a control voltage level and the fine adjusting circuit being controlled by a voltage which is the difference between the control voltage and the detection voltage.

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Ibaraki, Japan

Keisuke Yamamoto