JPS5954048A - Video disc player of optical system - Google Patents

Abstract

PURPOSE:To enable the simultaneous reproduction of static pictures on 2-3 image screens, by adopting a paired auxiliary luminous flux type as a system for tracking on tracks constituted of numerous pit arrays. CONSTITUTION:The principle of a detection system is illustrated. One 4 of the pit face on a track and spot states 5, 6, 7 of the beam arrayed at a slight angle theta relative with the track are shown. The tracking system adopts a paired auxiliary luminous flux type, wherein the reflected light of the spots on both sides (+ or -1st order light) among the three beams divided by a diffraction grating is received with a photodiode and a tracking error signal is obtd. The signal is so controlled by a tracking servocontrol circuit in such a way that the signal difference from the spots 5, 7 on both sides is made to zero. Therefore, the central spot 6 (0 order) for controlling the focus and reading the signal is positioned on the track. Just a slight angle is thus required for the angle for positioning the spots (+ or -1st order light) 5, 7 on both sides on the adjacent track with respect to the track where the spot 6 exists.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an optical video disc player, and more particularly to an image reproducing apparatus suitable for still image information files.

Conventional optical video disc player (hereinafter referred to as optical VDP)
It is abbreviated as ), the playback signal is one set of audio.

If it is a video and a still image is played, only one screen is obtained.

The amount of information is small. Further, text explaining the video information on the screen or related information list requires a separate reproduction device (for example, a character display of a personal computer, a movie projector, etc.). When using a separate playback device, there are problems such as a control device that drives the other playback device in conjunction with still images of the optical VDP, which becomes very complicated and increases costs.

The present invention provides an optical video disc player including:
In particular, the object of the present invention is to provide a device that reproduces still images not only for one screen, but also for two or three screens in the optical system of a set of playback devices.

The present invention describes an auxiliary bare beam type (three beams, 0-order beams, and ±1
In addition to using the beams on both sides (±first-order beams) for tracking detection, the recorded signal can also be reproduced from the beams on both sides. This is what makes up the screen.

Optical VDP generally uses standard disks and long-duration disks.

It can automatically distinguish and play two types of discs, and the standard disc has a rotation speed of 1800 revolutions per minute and can play 11 degrees for 50 minutes on one side (60 minutes on both sides). This disc maintains the exact relationship between one track and one screen (one frame), and each track has 1 to 54,000 (
Since the frame number (screen number) up to the maximum) is recorded, you can enjoy random access (a function to search for the screen you want to see5) and various trick plays (3x speed, slow speed, frame-by-frame still images), and It is configured to display the frame number on the screen. Of these, still image reproduction will be explained with reference to FIG. In Figure 1, 1
The broken line represents the video signal and 2-channel audio signal on the disc.

is placed on one track from the inner circumference to the outer circumference.

2 indicates the state recorded in the form of a tran.

FIG. 3 is a still image.

The relationship between one track and one screen shows the trace status.

This shows how a still image can be obtained by repeatedly playing a certain track, skipping to the inner circumference, and returning to the original position on a standard disc that maintains accuracy. Next, a method for accurately tracing on a track will be explained with reference to FIG.

0 FIG. 2 is a principle diagram showing a method of detecting a tracking control signal of an optical VDP. 4 in the figure is 1 of the bit surface on the track.
5.6.7 shows the spot state of the beam aligned at a slight angle to the track. Generally, the optical VDP tracking method uses an auxiliary pair beam type, and in the optical VDP optical system, the laser beam is split into three beams (0th order light and ±1st order light) using a diffraction grating. 1) Form a spot as shown in 5.6.7 in Figure 2 on the optical disk surface via an ivy track following mirror, a 1/4°λ wavelength plate, and an objective lens.

Bu. 6 is the 0th order light, and 5.7 is the ±1st order light. Tracking control tracks spots on both sides.

This photodiode is detected by a photodiode.

The tracking mirror is configured to control the deflection angle of the tracking mirror so that the signal difference from the tracking mirror becomes zero. this.

At this time, the 6th beam spot (0th order light) is exactly.

This 6 bee because it is located in the center of the track.

It is possible to detect the music spot with a photodiode and reproduce audio and video through reproduction signal processing. Figure 3 shows the signal regeneration circuit. 8 is a photodiode, 9
, 10, and 11, and 10 is further divided into four parts. 5, 6.7 explained in Figure 2
If the beam spot of 5 is configured to be detected corresponding to 9.10.11, the signal detected in 9.11 will be compared by 18 operational amplifiers and a tracking control signal will be output from terminal 19. Further, the detection signal 10 is further divided into four, and is compared by the operational amplifier 12, and a focus control signal is outputted from the terminal 13. In addition, FM modulation is performed via a capacitor in 4.14.15.

The recorded playback signal is extracted and 16 playback signals are obtained.

Two channels of audio signals are sent from 17 through a processing circuit.

The signal and video signal are output.

The general optical VDP has been explained above.

The present invention will be explained below.

A method for detecting a tracking control signal according to the present invention.

A diagram of the principle is shown in FIG. Number 4 in the diagram is a truck.

One of the upper pit faces is shown. 5.6.7 is a tiger.

This figure shows the spot condition of beams lined up at a slight angle θ with respect to the target. The tracking method employs an auxiliary pair beam type, and a photodiode receives reflected light from both side spots (±1st-order light) of three beams separated by a diffraction grating to obtain a tracking error signal. Tracking error signal 5 is sent to spots 5 on both sides by a tracking servo circuit.
The signal difference from 7 is controlled to be 0. Therefore, the center spot 6 (0
The next light) is located just on the track.

The angle θ in order to position the spots (±1st order light) 5.7 on both sides of the track where spot B is located on the adjacent track as in the present invention is from spot 6 to spot 5.7. For example, if the distance l is about 50 μm, it may be configured to be about 1.37 degrees, which is a small angle.

An embodiment of a block diagram of a signal reproducing circuit according to the present invention is shown in FIG. In Fig. 5, if the reflected light of spots 5 and 6.7 explained in Fig. 5 are detected correspondingly in the photodiode light receiving pattern section of 9.10.11, the signal detected in 9.11 is the operational amplifier of 18. A tracking error signal is output from 19. Tracking servo is performed using this tracking error signal to control the beam so that it always traces one track by causing the beam to follow the track deflection that occurs in the radial direction due to eccentricity when the disk rotates. Furthermore, the 10 light receiving pattern sections are further divided into four parts, and the respective detection signals of the four parts are compared by 12 operational amplifiers 12 and outputted as a focus error signal. Focus servo is performed based on this focus error signal, and the disk rotates.

The objective lens is used to detect the vertical vibration of the disk that occurs when the disk moves.

The beam is always focused on the pit surface with accurate tracking.

Control so that the points are connected. At this time, it is needless to explain that the focus of the spot 5.7 in FIG. 4 for detecting the tracking error signal is focused in the same way as the spot 6. From the light receiving pattern of 10, FM is transmitted through the condenser of 14.15.
The modulated and recorded playback signal is taken out, passed through a preamplifier 20 and a DFM compensator 22, and a bandpass filter 22 is obtained, and the video signal is reproduced by a FIVIi modulator 23.
It is output from terminal 25 via switch 4.

Also 2902.3 MHz band pass filter and F
One of the two audio signals that has been FM modulated and recorded by the M demodulator is reproduced and output from the terminal 30.

Furthermore, 4302.81'4 (z bandpass filter and FM demodulator reproduces the other audio signal and outputs it from terminal 44. 26 is a 1H delay line, 27 is an FM demodulator, and the disc has scratches, etc.) 7. When a dropout occurs in the reproduced signal, the switch 24 switches to the FM demodulated signal after being delayed by 1H by the dropout detector 28.

Dropout noise occurs during playback.

This is to prevent

The light receiving pattern section of the photodiode 9 not only obtains a tracking error signal, but also FM-modulates and records it on the track that the light receiving pattern section 9 is tracking, for example, on the spot shown in FIG. The reproduced signal is amplified by 32 preamplifiers and 33 FM
compensator, 35 FM through 34 bandpass filters
The demodulator reproduces the original video signal and outputs it from the terminal 36.

Similarly, a portion of the photodiode photodiode 5 not only obtains a tracking error signal, but also sends an FM signal to the spot shown in FIG.
The modulated and recorded playback signal is transmitted to 38 preamplifiers,
390 FM compensation units, 40 bandpass filters, 41 FM demodulation units.

The original video signal is reproduced from the terminal 42 through the device.

It is something that gives strength.

Although the explanation will be omitted here, it goes without saying that the 9.11 light receiving pattern section can reproduce not only the video signal but also each audio signal once. Also a frame.

It can also be configured to display the number on the screen.

FIG. 6 is a diagram illustrating a trace state during still image reproduction in the optical VDP of the present invention. In FIG. 6, if the 0 solid line 46 is used as the center spot (0th order light) of 6 beams for focus control signal detection and signal reproduction, the solid line 45.
Reference numeral 46 indicates a trace state for tracking control signal detection and signal reproduction using spots on both sides (±1st-order light). As described above, according to the present invention, the spots of the three beams can be traced on different tracks and can reproduce different signals.

FIG. 7 shows an embodiment of a system connection diagram according to the present invention. 48, 49, and 50 are color monitors, 51.53 are speakers, 52 are stereo amplifiers, and 54° is the optical V of the present invention.
Indicates DP.

Each output of the optical VDP 54 is connected to the terminal 36 explained in FIG.

44.30.25.42, the output of terminal 36.

to the color monitor 48, the output of terminal 44.30 to the stereo amplifier 52, the output of terminal 25 to the color monitor 49
When the outputs of the terminals 42 are respectively connected to the color monitor 50, when a disc on which audio and video signals are recorded for a general moving image is played back on the optical VDP 54, the audio is output from the speakers 51 and 53 via the stereo amplifier 52. , the video is played back from the color monitor 49. Also color monitors 48 and 50
Also, the video signal one frame ahead or the next frame is reproduced on the color monitor 49. Also, when playing back a disc on which still images are recorded for each frame, the color monitor 48.
Starting from 49.50, you can play different still images.

Furthermore, as discs for business, education, and learning purposes, the main still image is recorded in a specific frame, and the main still image is supplemented in the frames before and after that.

Or a disk containing still images to explain.

When reproduced, the color monitor 49 becomes the center.

A still image is played back on the color monitor 48.

At 50, a still image is played that explains or supplements the main still image. In this way, color monitor 48.49.
50 so that they fall within the same field of view, it is possible to obtain very effective video information. Similarly, color monitor 4
9 to play the main still image, color monitor 48 to play the supplementary explanatory text in Japanese, color monitor 50 to play the supplementary explanatory text in English as a still image, etc. How to use the still images on the three screens. It is infinite, and is suitable for playing disc versions of publications such as complete art books, illustrated books, and travel books.

Although it is omitted in this explanation, a still image that is the center is recorded in a specific frame, and a still image with text that supplements the center still image is recorded in one of the frames before and after that, and a still image that is different from the video is recorded in the other frame. Such a disc can be played back if audio that explains or supplements the main still image is encoded and recorded.

At the same time, explanations or supplements are provided in addition to the main still image.

The video and related content will be played back with audio.

It is also possible to

According to the present invention, in optical VDP, one set of optical systems 1.1 set of focus, tracking, and turnsh.

Focus servo is used to control the tracking servo spot for other types of servo systems.

Tracks located before and after the control spot.

With a simple configuration that looks like a race, when playing still images etc. 1°,
In addition to capturing still images on one screen, you can use the spot for tracking control signal detection to simultaneously display still images on up to two other screens.
Since it can be played back within the field of view, it can be used extremely effectively and with simple operations, such as video information files.

II'I Also, since the three screens are adjacent frames on the disk, there is no need for a control device or the like for interlocking the three screens.

[Brief explanation of drawings]

Figure 1 shows the typical optical VDP during still image playback.
- An explanatory diagram of the track tracing state, Figure 2 is -. Detection power of tracking control signal of general optical VDP. FIG. 3 is a general signal reproducing circuit diagram, and FIG. 4 is a trucking system according to an embodiment of the present invention. Fig. 5 is a block diagram of a signal reproducing circuit according to an embodiment of the present invention, and Fig. 6 is a diagram showing a method of detecting a signal reproducing control signal according to the present invention. - Figure 7 is an explanatory diagram of the system connection state. It is a map reading. 5-7... Spot reflected light, 1゜18... Operational amplifier, 20... Preamplifier, 2
1...1M compensator, 22... Bandpass filter,
28...Dropout detector. 5 □ Agent Patent Attorney Usui 1) y,%iF↑happy,'F
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Claims (1)

[Claims] 1. A diffraction path for laser light using an optical pickup. Divide the beam into three or more beams, and send the ±1st-order beams on both sides of the central 0° dimension to the disk surface. In the auxiliary pair beam type tracking method, the beam of ±1st order light on both sides is reflected by a photodiode and received by a photodiode to obtain an error signal for tracking control. 5. An optical video disc player characterized in that the optical video disc player is configured to trace a track of 5 for tracking, and to obtain an error signal for tracking control from the ±1st-order light beams on both sides, and also to read a recording signal.