JPS6165152A - Method and apparatus for inspecting defect of information signal recording disc - Google Patents

Abstract

PURPOSE:To attain an accurate and precise defect inspection for a short period by monitoring and reproducing an electrically defective part detected by any one of plural inspecting machines executing tests simultaneously by a master machine on occasion to decide the defect. CONSTITUTION:The inspecting machines 11-1n are connected to the master machine as slave machines. Inspecting parts 81-8n in the inspecting machines 11-1n detect the generating position of a dropout or a tracking error from a reproduced signal including a composite video signal obtained by reproducing a recording disc for an information signal to be inspected. A fixed track section arranged before and after the generating position is repeatedly reproduced from the detecting time and the reproduced picture is displayed on a monitor 6. When the reproduced picture is decided as no defect visually, reproduction for detecting the generating position of a dropout or a tracking which may be generated after the fixed track section is started after the repeated reproduction. If the presence of the defect is decided from the visual observation of the reproduced picture, the reproduction of the disc is completed in the fixed track section.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a method and apparatus for inspecting defects on information signal recording disks, and in particular, information signals are recorded on spiral tracks or the like as changes in geometric shape. The present invention relates to a method and an inspection apparatus for inspecting defects such as deformed portions and scratches on the surface of dust 1 on the surface of an information signal recording disk that significantly deteriorate the quality of reproduced information No. 18.

BACKGROUND OF THE INVENTION Conventionally, analog information signals such as composite video signals and audio signals are subjected to frequency modulation (FM), etc., and then recorded on spiral or concentric tracks as changes in geometric shapes such as intermittent bit strings. information signal recording disc (
(hereinafter referred to as disk) is known. During the manufacturing process of such a disk, a convex deformed portion where a portion of the disk surface is raised like a protrusion or a concave deformed portion where a portion of the disk surface is sunken may occur. Further, during the disk manufacturing process, the surface of the disk may be contaminated with stains, dust, etc., causing the bits to become buried, or may be scratched, resulting in the generation of false bits.

A reproduction needle having an electrode serving as a reproduction scanner is slid on the disk, and the capacitance between the disk having electrode capability and the electrode of the reproduction needle changes in accordance with the geometric shape change. In a disc playback device that reads and plays back recorded information signals by utilizing this fact, if the disc has the above deformed part and the playback needle scans the convex deformed part,
The playback needle jumps up on its convex deformed portion and then lands, bouncing again until a certain amount of time elapses before it gently slides into contact with the disk surface. In this case, depending on the direction of inclination of the convexly deformed portion, the playback needle may jump in a direction other than the track scanning direction, and in that case, the playback needle may move from the track it was scanning to another track. tracking errors may occur. Also, during the period when the playback needle is jumping up as mentioned above, the information signal cannot be picked up and played back, so some signals may be missing in the playback signal (
Dropout) occurs. Furthermore, when the reproducing needle scans a concave deformed portion, stain, dust, or scratch on the surface, a dropout occurs in the reproduced signal, which significantly deteriorates the quality of the reproduced image (3). Therefore, a shipping inspection is required at a disk manufacturing factory to determine the quality of the disk.

Therefore, the present applicant previously proposed a method and apparatus for inspecting the above defects in Japanese Patent Application No. 58-108882. According to this proposed invention, from the playback signal (including at least a composite video signal) of the disc played by the disc playback device, the inspection device determines the dropout occurrence period, its occurrence position, or the presence or absence of tracking error. By automatically detecting the defect and automatically determining the presence or absence of a defect based on the detection, it has the advantage of improving the reliability of inspection.

Problems to be Solved by the Invention However, in the above-mentioned process and equipment, the entire surface of the disk is inspected regardless of the presence or absence of defects, and in addition, a margin is set to suppress variations in the criteria for determining the presence or absence of defects. Therefore, defects that are tolerable to human vision and cause almost no deterioration of image quality may be determined to be defective.Therefore, after the automatic inspection is complete, only discs that are determined to have defects will be inspected. The defect judgment part was played back and the monitor image was viewed by the inspection port, and the inspector visually checked the final result to determine whether there was a defect or not, so the inspection took a long time. There were some problems.

Therefore, the present invention connects multiple inspection units as child units to a master unit that has a separate judgment aspect, and allows multiple inspections to be performed at the same time. It is an object of the present invention to provide a defect inspection method and apparatus for an information signal recording disk, which solves the above-mentioned problems by monitoring playback using a master unit at any time and visually determining the presence or absence of defects.

Means for Solving the Problems/Invention A defect inspection method detects the position of occurrence of dropout or racking error from a reproduced signal containing at least a composite video signal obtained by reproducing an information signal recording disk to be inspected. is detected, and from the time of detection, a certain track section before and after the above-mentioned occurrence position is repeatedly played back, and
Display the reproduced image by the repeated reproduction signal on the monitor,
When it is determined that there is no defect by visual inspection of the reproduced image, the above-mentioned certain track section is continuously played through repeated playback, and playback is started to detect dropouts or tracking errors after recording, and by visual inspection of the reproduced image, The present invention is characterized in that when it is determined that there is a defect, reproduction of the information signal recording disk is completed in the predetermined track section.

Furthermore, the defect inspection device of the present invention has a first function of repeatedly reproducing a certain track section before and after the position where the dropout or tracking error occurs, and reproducing according to an external control signal input during this repetitive reproduction. A plurality of inspection machines having a second function of starting the reproduction of the track after the completion of the track section or a certain track section, and a plurality of inspection machines are respectively connected as a plurality of inspection machines, and the plurality of inspection machines perform the above-mentioned repeated reproduction. The reproduced image based on the reproduction signal of the first inspection machine is displayed on a monitor, and the reproduction operation of the first inspection machine is controlled in the same manner as the above inspection method based on the judgment signal corresponding to the judgment of the presence or absence of defects by visual inspection of the reproduced image. If there is another inspection machine that generates and outputs a control signal that repeatedly performs playback, the same operation as above is repeated.

Function: In the defect inspection method of the present invention, the detection signal obtained by electrically detecting a defect is centered at the position where the defect occurs. The presence or absence of a defect is visually determined by repeatedly reproducing a certain track section, and if it is determined that there is a defect, the reproduction of the disc is immediately terminated and the defect inspection of the disc is completed.

Therefore, compared to the proposed inspection method, which inspects the entire surface of the disk regardless of the presence or absence of defects and then performs a visual inspection to finally determine the presence or absence of defects, it is time-consuming. disappears. Also, if it is visually determined that there are no defects during the above-mentioned repeated playback, everything is cleared, and the tracks after the above-mentioned certain track section are played again, electrical detection of the defect position is started, and the inspection continues. .

In addition, in the defect inspection apparatus of the present invention, multiple inspection machines can be
It will be possible to automatically inspect multiple disks for defects simultaneously through centralized control using AR. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The defect inspection method and apparatus of the present invention will be described in more detail below with reference to embodiments and the drawings.

Embodiment FIG. 1 shows a block system diagram of an embodiment of the present invention, and FIG. 2 shows a schematic connection diagram of an embodiment of the present invention.

In both figures, the same components are given the same reference numerals.

In both figures, 0 (n is a natural number, for example 16) test R1+ to 1n are connected to the master device 2 as child devices.

The main package 2 includes a video switcher unit 3, an I10 unit 4, a personal computer 5, a monitor television receiver (hereinafter referred to as monitor TV) 6, and a monitor device 7.
It consists of - The test sections 11 to 1n are connected to the test sections 81 to 8n and an interface circuit as shown in FIG.
/F) consists of 91 to 9n. Inspection section 81-8n
shows a disc playback device that plays the above-mentioned disc, a reproduced composite video signal, a dropout detection signal, and a status from this disc playback device.

It consists of a testing circuit to which signals such as a video mute signal are supplied, and its configuration is approximately the same as that of the testing device disclosed in Japanese Patent Application No. 108882/1982 proposed by the present applicant. The dropout detection signal mentioned above is a pulse with a time width corresponding to a dropout, which is detected by a known method based on the reproduction FM signal of the disc, and the above inspection circuit is based on this dropout detection signal. For dropouts that appear to humans as only one dropout, such as dropouts that occur multiple times at short intervals, a dropout test signal with a time width that corresponds to the human perception is generated. Dropout test signals obtained by detecting phase dropouts that cause 1-line lag or screen drift in the playback screen, such as a dropout that occurs in the first 1H of a vertical synchronization pulse, even if the dropout is extremely short. etc. occur.

Furthermore, the test circuit detects whether the address signal in the reproduced signal changes regularly or not, and if it does not change regularly, it determines that a tracking error has occurred and outputs a tracking error detection signal. Furthermore, if the test circuit detects the dropout or tracking error described above,
A control operation is performed on the disk reproducing apparatus to repeatedly reproduce a certain track section before and after the detected track position of the dropout or tracking error from the detection time at the same speed as during normal reproduction.

To explain this in more detail, assuming that the track position at which a dropout or tracking error on the disc is detected is in the track section 100 shown by diagonal lines in FIG. As shown in B), the track section 1 is
After scanning 00, by the above detection, a certain track section T before and after centering on the track section 100 is scanned at 1x speed in the opposite direction.
The program returns to the initial position, and from this position, forward single-speed playback is started, and when the last position under the constant track section is reached, reverse single-speed playback is resumed. Hereinafter, this operation is repeated. However, if the dropout in the track section 100 is caused by a convexly deformed portion, the convexly deformed portion may be scraped off by the above-described repeated reproduction and the dropout may disappear. In that case, the disc reproducing device starts reproducing the tracks after the certain track section T at 17 times the speed from that point. Figure 8 (
B) schematically shows the movement of the reproduction needle when the dropout disappears in the third repeated reproduction.

Incidentally, when the track section 100 is detected, it may be arranged to return to the initial position of the constant track section T by a known high-speed search operation.

The inspection units 81 to 8n send a loop signal to notify the personal computer 5 when the disc playback device continues the above-mentioned repeated playback a certain number of times (for example, 4 times), and a loop signal to inform the personal computer 5 that the disc playback device continues the above-mentioned repeat playback a certain number of times (for example, 4 times). The above-mentioned video mute signal indicating that the lead-out section is being played back are sent to l/○ through I/Fs 9+ to 9n, respectively.
On the other hand, the start signal, stop signal, or pass signal from the personal computer 5 is supplied to the I/F 20 in the unit 4 through the I/F 19 in the l/○ unit 4, and the start signal, stop signal, or pass signal is supplied to the inspection unit through I/Fs 9+ to 9n. 81~8n
supplied to

FIG. 3 shows a circuit diagram of an embodiment of any one of the above f/F 9 + to 90 I/Fs. In the figure, terminal 22
A video mute signal from a corresponding one of the test sections 81 to 8n enters the inverter 23, 24, and is output from the terminal 25 to the I10 unit 4 through the inverters 23 and 24, respectively. An audio mute signal is also input to the terminal 26 from the above-mentioned one inspection section, and is applied to the clock terminal of the counter 27, where it is counted. Here, the audio mute signal is a signal that has a different logical value during normal playback (forward constant speed playback) and during other playbacks.On the other hand, the repeated playback of the certain track section is different from that during normal playback. Since forward playback and reverse playback at the same speed are repeated alternately, the counter 27 counts the number of times the above-mentioned repeat playback is repeated.

When the count value reaches r4J, the counter 27 outputs a signal at a predetermined level from its Q3 output terminal, which is applied to the RS flip-flop from the NANO circuits 29 and 30 through the inverter 28 to set it in the set state. As a result, the high-level signal taken out from the two NAND circuits passes through the impark 31 and passes through the terminal 32 to I1.
The loop signal is output to the I/F 20 in the 0 unit 4.

In addition, before the number of repeated plays reaches 4, or 4
The inspection units 81 to 80 are configured to resume high-speed playback if the convex deformed portion on the disk is scraped off by the playback needle and dropout no longer occurs. Therefore, in such a case, the mono multi 36 to which the input audio mute signal of the terminal 26 is supplied
and the output signals of the integrating circuit 37 respectively become high level,
The output signal of the NAND circuit 38 becomes low level.

On the other hand, at the terminal 33, a signal that becomes low level only during reverse playback is transmitted from the corresponding one of the test sections 81 to 8n to the NOR circuit 35 via the inverter 34.
It is supplied together with the output signal of the ND circuit 38, and is further supplied to the monomulti 39. The signal is applied to the reset terminal of the counter 27 through the NOR circuit 40 and the inverter 41, and at the same time as this is reset, the flip-flop consisting of the NAND circuits 29 and 30 is reset by the output signal of the NOR circuit 40.

On the other hand, a low level start signal from the I10 unit 4 is applied to the base of the NPNI transistor 44 via the terminal 42 and the inverter 43, which is turned on and supplied from its collector to the first inspection section via the terminal 45. be done. Similarly, the low level bus signal and stop signal from the I10 unit 4 are applied to the pace of the NPN transistor 48.53 via the terminal 46.51 and the inverter 47.52, and from the collector thereof via the terminal 49.54. It is output to the first inspection section.

As will be described later, the bus signal is a signal that is input by the inspector from the keyboard of the personal computer 5 when it is visually determined that there is no defect, and causes high-speed playback of the next track and subsequent tracks from repeated playback of the disc. . This bus signal is applied to the NAND circuit 50. NOR circuit 40. The signals are applied to the reset terminal of the counter 27 through the inverters 41 to reset it. In addition, the playback of the disc is stopped immediately by the above stop signal,
Furthermore, reproduction of the disc is started by the start signal.

Returning to FIG. 1 again, the reproduced composite video signals taken out from the inspection sections 81 to 8n are sent to the video switcher.
Only the reproduced composite video signal from one inspection machine is supplied to the video switcher 10 in the unit 3, where it is repeatedly reproduced in accordance with the select signal from the l1016, and is selectively outputted through the buffer 11 to the synchronization separation circuit 1.
2 and the monitor TV 6, respectively. Note that when there are two or more inspection machines that are performing repeated playback at the same time, only the repeatedly reproduced composite video signal of the inspection machine that is the most immersed is transmitted to the video switcher 10 according to a predetermined priority order.
The other inspection machines that are selectively outputted and performing repeated reproduction continue to perform repeated reproduction thereafter and enter a standby state. When the repeatedly reproduced image of the first inspection machine that comes first is inspected, the repeatedly reproduced image of the next highest priority inspection machine is inspected, and in the same way, inspections are carried out sequentially according to the priority order. It will be done.

The sync separation circuit 12 supplies a horizontal sync signal and a vertical sync signal to the superimpose circuit 13, respectively. The superimpose circuit 13 receives superimpose data, channel select signals, etc. that are input via a central processing unit (CPU) 14, an input/output device (hereinafter referred to as I10) 15, and an I/F 17 in the personal computer 5. An impose video signal is generated, superimposed on the reproduced composite video signal from the buffer 11, and then output to the monitor TV 6.

CPU 14 is connected to I1015 and 18 of I10 unit 4, respectively, through bidirectional path lines. l1
015 is for controlling the video switcher 10, and superimpose data etc. are sent from the A boat to T/F.
17, and select data is output from the other B and C ports and supplied to the video switcher 10 via the I/F 1a.

On the other hand, l1018 is for controlling the inspection machines 11 to 1n, and supplies 7 bits of its 8-bit A port output to r/F19, and the remaining 1 bit output to I/F
20, and the inspection machines 11 to 1n are supplied to the B and C ports.
A video mute signal and a loop signal passed through I 1020 are provided.

FIG. 4 shows a circuit diagram of one embodiment of l1019.

In the figure, terminals 600 to 606 are the 1st to 7th bit terminals of the A port of l1018.
The 4-bit data for selecting the inspection machine to be controlled, which is inputted at 03, is converted by the decoder 61 into n bits (for example, 16 bits). The n-bit output signal of the decoder 61 is a control signal for specifying any one of the zero inspection machines 11 to 1n, and is a control signal for specifying one of the 0 inspection machines 11 to 1n.
2n respectively to tristates 631-63n.

64+ to 64n and 65+ to 65n, respectively. A start signal enters the tristates 631 to 63n from the terminal 604, and the tristates 641 to 64n
A stop signal is input from the terminal 605 to the tristates 65+ to 65n, and a pass signal is input from the terminals 60 to the tristates 65+ to 65n.

The start signal selectively output from the tri-states 631 to 63n is sent to the terminal 69 through the inverters 661 to 66n.
1 to 69n are output to l109+ to 9n. Also,
The stop signal selectively output from the tri-states 641 to 64n passes through inverters 67+ to 67n to terminal 7.
Output from 0+ to 70n to l1091 to 9n. Furthermore, the pass signals selectively output from the tri-states 651 to 65n are passed through the inverters 68) to 68n to the terminals 71+.
~71n is output to 1109+~9n.

FIG. 5 shows a circuit diagram of one embodiment of 11020.

In the figure, the video mute signal inputted to terminals 731 to 73n is supplied to tristates 751 to 75n,
The loop signals entering terminals 741-74n are supplied to tristates 761-76n. On the other hand, terminal 77
is the 8th bit terminal of the A port of l1018, and the selection signal that comes from this is sent to tristates 751 to 751 through inverters 78 and 79 and Schmitt trigger circuit 80.
5n as a control signal, and the output signal of the inverter 79 is applied to the inverter 81 and the Schmitt trigger circuit 8.
2 as control signals through tri-states 761-76
n. Therefore, tristate 7°51~7
5n and 761 to 76n, one is in a high impedance state while the other is in a state where a signal passes. The output signals of tristates 751 to 75n or 761 to 76n are output through terminals 831 to 83n, and half of them are output to l101.
The remaining half is input to the C port.

In the defect inspection apparatus having such a configuration, all operations are performed using the keyboard of the personal computer 5 (
However, operations such as loading the disk into the inspection machines 11 to 1n are excluded. ). The operating states of the test devices 11 to 1n (such as whether they are in a repeated playback operation or not in operation) are displayed on the monitor display device 7 shown in FIGS. 1 and 2. And inspection R1
+~ When an inspection machine repeatedly performs a reproducing operation within a day, a reproduced image based on the reproduced composite video signal of that one inspection machine is automatically displayed on the monitor TV 6.

Then, the inspector visually checks the reproduced image on the monitor TV 6 to determine whether it is a defective image or an image that cannot be said to have a defect, and if the judgment result is that there is a defect, a stop signal is sent by operating the keyboard of the personal computer On the other hand, when there is no defect, a pass signal is generated by operating the keyboard, and high-speed playback for defect inspection of tracks after a certain track section during repeated playback is restarted. In order to prevent mistakes, the inspection machine number (inspection numbers pre-assigned to numbers 11 to 1n) is superimposed on the monitor TV 6. This display can be turned off if necessary.

Next, an embodiment of the inspection method of the present invention will be described with reference to the flowchart of FIG. CPU14 is the first light setting (
For example, initial settings of I10 unit 11, etc., counter 27
etc.) (Step 90)
Inspection 1 performs high-speed playback of the disc (for example, 17x playback) and detects the positions where dropouts or tracking errors occur. Scans for the presence or absence of video mute signals from 1 and 11 to 1n, and determines which inspection machine It is checked whether the reproducing operation is being performed (step 91). Next inspection)
Shallow 1! ~1n, the CPU 14 scans and imports loop signals from one or more inspection machines that detect dropout or tracking error occurrence positions and repeatedly reproduce a certain track section that includes the occurrence position as the center ( Step 92), the status of each inspection machine is displayed on the monitor device 7 (Step 93).

Next, the CPU 14 determines whether or not there is an inspection machine that is repeatedly playing back depending on whether or not a loop signal has been captured in step 92 (Step 94).・Switcher・
The process passes through the unit 3 (step 95) and waits for an inspector's visual judgment instruction of the reproduced image (step 96). There are three types of instructions: stop, pass, and next, and the inspector operates the keyboard of the personal computer 5 and stops when he or she determines that there is a defect.

If it is determined that there are no defects, it will pass, and the reproduced image will be put on hold for the time being, and if it wants to repeatedly view the reproduced images from other inspection machines, it will instruct next.

The CPU 14 determines whether the instruction is next or not (step 97), outputs a stop signal if it is not a next instruction but a stop instruction, and outputs a pass signal if it is a pass instruction.
Steps 98 and 99) are used to determine whether there are any other inspection machines that are repeating playback, and if the next instruction is issued, the process immediately moves to step 9.

If there is another inspection machine that is repeatedly playing, the CPU 14
If there is no data, the processing operations of steps 95 to 99 described above are repeated again, and if there is no data, the process returns to the first step 90. In addition, C.P.
U14 also returns to the first step 90 when it is determined in step 94 that there is no inspection machine undergoing repeated regeneration. In this way, the reproduced images of the defective parts electrically detected by the n inspection machines 11 to 1n are displayed on the monitor display device at any time, and the images are finally inspected based on the criteria of whether or not they are acceptable on the reproduced screen. The inspection machine that reproduces the disk determined to be defective is allowed to complete the reproduction operation, and there is no need to perform a full-scale inspection, and there is no need for visual judgment after the full-scale inspection.

FIG. 7 is a signal waveform diagram illustrating the operation of one inspection machine. When the start signal shown in FIG. 7 (C) is input by keyboard operation, the video mute signal is
As shown in A), the level becomes high (indicating that the video mute is released), and reproduction of the recorded program section of the disc is started. Thereafter, when a loop signal is output from the inspection state at time tl as shown in FIG. 7(B), the CPU 14 automatically outputs the loop signal at time t2r (FIG.
As shown in [), a signal is output to select () to select this inspection machine, and the reproduced image is displayed on the monitor TV6.Then, if the inspector determines that there is no defect by visually checking the monitor image, the keyboard Figure 7 (
When a pass signal as shown in E) is generated at time t3, and a loop signal as shown in FIG. As shown, the select signal is output, and images based on the reproduced signals that have been repeatedly reproduced since time t5 are displayed on the monitor TV 6. After viewing this reproduced image, the inspector determines that there is a defect and uses the keyboard to set the time t.
When the stop operation is performed at time t6, a stop signal is generated and output from time t6 as shown in FIG. 7(D), thereby ending the inspection of this inspection machine.

Effects of the Invention As described above, according to the method of the present invention, when the position of occurrence of a dropout or tracking error is electrically detected, the vicinity of the occurrence position is repeatedly reproduced, and the presence or absence of defects is visually checked by visually inspecting the repeatedly reproduced image. Since the inspection is immediately terminated when it is determined that there is a defect, more accurate defects can be detected in a shorter time without wasting time, compared to the case where a visual defect inspection is performed after the entire surface inspection. Furthermore, according to the device of the present invention, since multiple inspection machines are centrally controlled at the same time, defect inspection of a large number of disks can be carried out more quickly and automatically. It has the advantage of being able to reduce the number of devices.

[Brief explanation of the drawing]

FIG. 1 is a block system diagram showing an embodiment of the device of the present invention;
Fig. 2 is a schematic wiring diagram of an embodiment of the device of the present invention; Fig. 3;
4 and 5 are circuit diagrams for explaining the operation of an embodiment of each part of the block system shown in FIG. A signal waveform diagram for explaining the operation of one inspection machine according to the invention,
FIG. 8 is a diagram that does not schematically show an example of a track section where dropouts and the like occur and how the reproduction needle scans. 11-1n...-Inspection section, 2... Main modification, 3... Video switcher unit, 4... I10 unit,
5... Personal computer, 6... Monitor television receiver (monitor TV), 7... Monitor device, 81-8n... Inspection department, 91-9n, 16, 17° 19.20 ...Interface circuit (I/F), 1
0...Video switcher, 14...Central processing unit (
CPU), 22.73+ ~ 73n =- video mute signal input terminal, 25... video mute signal output terminal, 26... audio mute signal input terminal, 27
...Counter, 32...Loop signal output terminal, 42
．． 60a...Start signal input terminal, 46°606.
...Pass signal input terminal, 51.60s...Stop signal input terminal, 74+~74n...Loop signal input terminal.

Claims (4)

[Claims] (1) Detect the position where a dropout or tracking error occurs from a reproduced signal containing at least a composite video signal obtained by reproducing the information signal recording disk to be inspected, and A certain track section is repeatedly played back, and a playback image based on the repeated playback signal is displayed on a monitor, and if it is determined that there is no defect by visual inspection of the playback image, dropout is performed after the certain track section following the repeated playback. Alternatively, reproduction is started to detect the position where a tracking error occurs, and when it is determined by visual inspection of the reproduced image that there is a defect, reproduction of the information signal recording disk is completed in the certain track section. Defect inspection method for information signal recording disk. (2) The playback for detecting the position where the dropout or tracking error occurs is performed at a faster speed than during normal playback, and the repeat playback is performed at the same speed as during normal playback. A method for inspecting defects in an information signal recording disk according to scope 1. (3) Detect the position where a dropout or tracking error occurs from a reproduced signal containing at least a composite video signal obtained by reproducing the information signal recording disk to be inspected, and a first function of repeatedly reproducing a fixed track section; and a second function of completing playback or starting the reproduction of tracks after the fixed track section according to an external control signal received during the repeated playback of the fixed track section. displaying on a monitor a reproduced image based on a reproduction signal from one of the plurality of inspection machines which is connected to each of the plurality of inspection machines as slave units and which is performing the repeated reproduction; When it is determined that there is no defect by visual inspection of the reproduced image, based on the determination signal, the first inspection machine starts reproduction for detecting the position where dropout or tracking error occurs after the above-mentioned certain track section, and the other When it is determined that there is a defect, a control signal is generated to immediately complete the regeneration operation of the one inspection machine based on the determination signal, and if there is another inspection machine that is repeatedly performing the regeneration, the above A defect inspection device for an information signal recording disk, characterized in that it consists of a master device that repeats the same operation as the above. (4) The inspection device performs high-speed playback to detect the position where the dropout or tracking error occurs, and during the repeated playback, it alternately repeats forward playback and reverse playback at the same playback speed as during normal playback. A defect inspection device for information signal recording disks according to claim 3, characterized in that: