Tokyo Broadcasting System, Inc.

Nec Corporation

Nippon Electric Co., Ltd.

Takaya Morita

Akihiro Takahashi

Masao Inaba

Kazuo Kashigi

Hideo Makita

Hidekado Nishihara

Takashi Tachibana

Yoitiro Hoshi

Transmitting and receiving apparatus, for transmitting an input video signal having 525 lines/field progressive scanning by converting the input video signal into a signal compatible with the NTSC system, and for reproducing from that NTSC-compatible signal a video signal having 525 lines/field progressive scanning. The transmitting apparatus has a first separating system for separating vertical high frequency components in a three-dimensional horizontal-vertical-temporal domain from the input video signal; a modulating system for modulating the separated components from the first separating system by .mu.-modulation; a system for filtering a modulation output from the modulating system to remove a lower sideband component from the modulation output, the filtering system having a Nyquist characteristic; and a system for multiplexing a filtered output from the filtering system to form the NTSC-compatible signal. The receiving apparatus has a second separating system for separating the multiplexed filtered output from the NTSC-compatible signal; and a system for reproducing a video signal having 525 lines/field progressive scanning in response to the filtered output from the second separating system. More particularly, the vertical high-frequency components have a vertical spatial frequency of 515/4 cph, and the filtered output from the filtering system has a frequency band of 2.2 MHz to 4.2 MHz.

Apparatus for transmitting an extended definition TV signal having

In a wide-aspect television system, apparatus is provided for producing a source television signal for a wide aspect television screen, which source signal has the same horizontal and vertical synchronizing frequencies, but fewer effective scanning lines than a conventional television system. The wideaspect television system further includes apparatus for expanding the time base of the mentioned source television signal in the horizontal direction by a predetermined ratio. Further included is an apparatus for receiving a time base-expanded television signal produced by the expanding apparatus for arranging video information of both side areas of a time base-expanded television signal into top and bottom added scanning lines. A remaining area of the time base-expanded television signal substracted by both mentioned side areas have a horizontal scanning period substantially equal to a horizontal scanning period of the conventional television system. The total effective scanning lines of the source television signal and the top and bottom added scanning lines substantially corresponds to the total effective scanning lines of the conventional television system.

Aspect ratio-improved television system compatible with conventional

A memory write-in control system provides for each dot a plurality of color designating bits representing color information for the dot as well as a set of mask command bits corresponding to the respective color designating bits. The memory content is changed in accordance with the color designating bits only when the mask command bits are at one logic level. The memory bit content is unchanged when the mask command bits are at the other logic level irrespective of the color designating bits.

Memory write-in control system for color graphic display

Growing community of inventors

Tokyo, Japan

Takaya Morita