Matsushita Electric Industrial Co., Ltd.

Takayuki Sagishima

Teruo Kitani

Reiichi Sasaki

Takaaki Baba

Masanobu Tanaka

Yoshimori Nakase

Hiroshi Ikushima

A demodulator circuit of PAL type color television signals which is arranged so as to demodulate the correct polarity R-Y signal without controlling the f.sub.H /2 line switching pulse in phase.

Demodulator circuit for color television signals of PAL system

A flickerless 3-D TV viewing system is designed to be used with a single TV receiver set and with a set of stereoscopic glasses composed of light shutters. The system includes a signal-distributor, a set of memory devices, a signal-selector, a synchronous signal separator, a discriminator and a timing circuit. The system is very comfortable for the user during 3-D TV viewing.

3-D TV Systems

A color signal demodulating device designed so that a local subcarrier oscillator generates a demodulating signal which is both synchronized and inverted in phase with respect to a color signal at each horizontal scanning period so as to demodulate an R-Y signal and which reverses phase with each horizontal scanning period; a bust signal and a signal inverted in phase therefrom are alternately switched therebetween and used to drive the local subcarrier oscillator. The output of this local subcarrier oscillator can be used for both the demodulation signal for the R-Y carrier and as the demodulation signal for the B-Y demodulator.

Color demodulating apparatus

In the PAL system, the demodulating axis for one of the two color difference signals, i.e. the R-Y signal, is transmitted switched in phase 180.degree. at each horizontal scanning period. In order to reproduce this signal, a demodulator circuit for color television signals is provided for producing a R-Y signal of the correct polarity, using a line switching signal not controlled by the phase of the transmission signal, and having a frequency half that of the horizontal frequency.

PAL Demodulator having non-synchronized line switch

A television receiver including: television signal receiving means for simultaneously receiving two different television signals to produce two different image signals, a first and a second image signal corresponding to the television signals; synchronous signal producing means for producing vertical synchronous signals and horizontal synchronous signals from the two image signals; memory means for sampling and storing the second image signal; driving pulse producing means for producing driving pulses to drive the memory means in accordance with the synchronous signals supplied to the driving pulse producing means from the synchronous signal producing means; mixing means for producing a mixed image signal by inserting, into the first image signal under the control of the driving pulses, the second image signal read out from the memory means by the driving pulses; and display means for displaying the output of the mixing means; wherein the second image signal of each horizontal synchronous period is sampled by the memory means into N.sub.H sampled signals, and n sampled signals which are sampled from n adjacent horizontal lines of the second image signal, respectively, and which correspond to each other in vertical direction on a TV screen are summed and integrated into one sampled image signal element whereby N.sub.H sampled image signal elements for one horizontal synchronous period upon read-out are formed from n.times.N.sub.H sampled signals of n adjacent horizontal lines and stored by the memory means. Since the information of all of the n adjacent horizontal lines is utilized for the displayed image, the displayed image can be of high quality.

Television receiver

A VTR signal discriminating apparatus for a television receiver generates discriminating signals when the receiver having this apparatus is receiving signals e.g. from a home use video tape recorder (VTR). This apparatus detects video head switching noises mixed in signals from the VTR having two video heads which are alternately switched every field of the signals by counting the number of apparent sync signals received within a given period of time. Thus, video signals originating from a broadcast station are distinguished from video signals originating from the VTR and the invention output denotes the presence of the appropriate signal. A television receiver can be modified in response to the invention output to accommodate the characteristics of the particular video signal received.

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Suita, Japan

Takayuki Sagishima