Sony Corporation

Masaaki Arai

Takayuki Sasaki

Noriyuki Yamashita

Akio Yamakawa

Minoru Morio

Koji Iijima

Katsuhiko Ueno

Masahiro Kanbara

A signal reproducing system for use in an optical disc player comprises a photodetector including at least first and second photodetecting elements which are so disposed that a beam spot is formed on the first and second photodetecting elements by a light beam caused to impinge upon and reflected at an optical record disc and are aligned along a direction of movement of a diffraction pattern appearing in the beam spot in accordance with a record track on the optical record disc, a phase shifter for varying at least a phase of one of first and second output signals obtained respectively based on detection outputs of the first and second photodetecting elements, a switch for causing the first and second output signals selectively to pass through the phase shifter in response to a direction of movement of the record track in relation to the light beam incident upon the optical record disc, and a mixer operative to add one of the first and second output signals derived from the phase shifter to the other of the first and second output signals so as to produce a reproduced information signal.

Optical disc player with phase shift dependent on disk rotation direction

Described is a method and a recording apparatus whereby audio and video signals can be recorded on a plurality of recording tracks on the same recording medium. A series of temporarily consecutive audio signals can be recorded across a plurality of tracks. On at least the audio track, information signals including the leading track number, the next following track number and the number of the video track bearing the corresponding video signals, are recorded. The track number data of the information signals on these audio tracks are written in corresponding positions of a digital, table memory. These control code data are recorded on a predetermined control track on the recording medium such that a series of desired audio signals and the corresponding video signals can be selectively reproduced smoothly and promptly by first reading the control track and then reproducing the audio and video tracks in accordance with the control code data information.

Signal recording apparatus and method

A digital conversion system for a color video signal comprising a system which selectively converts an analog composite color video signal and analog primary color video signals to digital signals includes: a matrix circuit (17) which forms a luminance signal and first and second color difference signals from the input analog primary color video signals; and a switching circuit (18) which converts the first and second color difference signals to a sequential color difference signal. A switch (28) selects the luminance signal from the matrix circuit (17) or the input NTSC analog composite color video signal. A first analog to digital converter (41) receives an output from the switch (28); and a second analog to digital converter (42) receives the sequential color difference signal. A digital composite color video signal or a digital luminance signal is obtained from the first analog to digital converter (41), and a digital line sequential color difference signal is obtained from the second analog to digital converter (42). The line sequential chrominance signal can be digitized by a single inexpensive A/D converter which has a slow processing speed, so as to produce an inexpensive digital conversion system which is small.

Digital conversion system for a color video signal that is capable of

The present invention comprises a signal generator which uses digital memory for generating a digital signal which has a value which periodically varies with a memory having 2.sup.n addresses in each of which data for one period of the digital signal is stored and includes a circuit for multiplying a digital control input having a variable value by a predetermined coefficient and includes an integrator for integrating the control input multiplied by said coefficient at every predetermined clock signal so as to produce an address signal for said memory and said address signal varying step by step at a predetermined number of intervals corresponding to said digital control input.

Signal generator using digital memory

A non-linear digital emphasis circuit for non-linearly emphasizing a high frequency component of an input digital video signal in accordance with an amplitude of the digital video signal. This emphasis circuit comprises: a digital filter for emphasizing the high frequency component of the digital video signal; and a memory in which a data conversion table to non-linearly compress the amplitude of the digital video signal is written and to which the digital video signal is supplied as an address input. The respective polarities of the address input of the memory and of the readout output therefrom are inverted by a polarity inverter in accordance with the polarity of the digital video signal. With this emphasis circuit, an error of the frequency characteristic and time and temperature changes thereof are not caused and no adjustment of the characteristic is needed. Also, this circuit can be formed as an integrated circuit by utilizing only digital circuits.

Non-linear digital emphasis circuit

Color video still picture playback apparatus enhances the quality of a color still picture reproduced from a video record medium. The reproduced signal is formatted as one field of video containing a succession of lines with first and second color difference signals provided in alternating line sequence. The reproduced picture, after processing, is formatted as alternating first and second fields, each having a plurality of lines such that the lines of the second field are interpolated between successive lines of the first field, and the color difference signals are provided as continuous signals, with interpolated signals being provided in alternate lines. To achieve this, first and second switches operated at the field rate are associated with first and second delay lines of one-half-line and one line delay times, respectively, and an adder circuit connects the outputs of the delay lines to one input of the second switch. This interpolates and half-line-offsets the lines of the video signal to produce the interpolated second field of the luminance signal. Third, fourth, and fifth switches, associated with third, fourth, and fifth delay lines and a second adder circuit interpolate the color difference signals so that outputs of the fourth and fifth switches provide continuous color difference signals. The third switch is operated at the field rate, while the fourth and fifth switches are operated at the line rate.

Growing community of inventors

Tokyo, Japan

Masaaki Arai