JP2649038B2 - Optical disk inspection device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for inspecting an optical disc or a magneto-optical disc (collectively referred to simply as an optical disc) for the presence or absence of a dropout and a well.

[Conventional technology]

It is a well-known matter that one of quality inspections of an optical disk or a magneto-optical disk is an inspection for the presence or absence of a dropout and a well.

None of the conventional apparatuses for performing this inspection can accurately determine the position on the disk where the dropout and the well are present.

[Problems to be solved by the invention]

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and has as its object to provide an inspection apparatus that can accurately determine a position where a dropout and a well exist.

[Means for solving the problem]

An inspection apparatus according to the present invention includes: a generation unit that generates inspection pit pattern data including inspection pit pattern data for each pit position; and a recording unit that records the pit pattern data generated by the generation unit on a disk to be inspected. Means, reading means for reading pit pattern data recorded on the disk by the recording means, and collating pit pattern data read by the reading means with pit pattern data generated by the generating means in pit units. Matching means for outputting an error signal and an error identification signal for identifying whether the error is a dropout or a source corresponding to a pit having a dropout or a source, and a dropout based on the error signal. Or error location information to identify the pit location where Is characterized in that comprises means for outputting, and storage means for storing in the said error identification signal and error position specifying information pair.

[Action]

After the inspection bit pattern data generated by the generating means is recorded on the disk by the recording means, and the data is read from the disk by the reading means, the collating means compares the data with the pit pattern data from the generating means. Matching is performed on a pit-by-pit basis, and an error signal and an error identification signal for identifying whether the error is a dropout or a well are output in response to a pit having a dropout or a well. Based on this error signal, error position specifying information for specifying a pit position where a dropout or a well is present is output. The error identification signal and the error position specifying information are paired and stored in the storage unit.

As described above, according to the present invention, since the position where the dropout or the well is present is detected in pit units,
The error position is determined with high accuracy. Also,
It can be determined whether the error is a dropout (data “1” disappears and changes to “0”) or an error (data “0” causes “1” to appear).
Further, since the error identification signal and the error position specifying information are stored in a pair in the storage means, the error position and the error type can be specified without storing all the data read from the disk. The result can be stored in data compressed form.

〔Example〕

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows an embodiment of the inspection apparatus according to the present invention. In this device, the pit pattern generation circuit 1
The pit pattern data a for inspection is generated. The generated data a is given to the recording control circuit 2 and the collation and error type discrimination circuit 3.

The recording control circuit 2 receives the given data a and the data a
Is supplied to the laser recording drive circuit 4 including a signal for recording control when recording is performed on the optical disc. The circuit 4 records the data a on the optical disc t to be inspected using the laser light c based on the recording control signal.

The amplifier and reproduction circuit 6 inputs a reproduction detector output d obtained by reading recorded contents of the optical disk 5 by well-known reading means (not shown), and outputs a reproduction digitized signal e obtained by digitizing the output d. The output signal e is supplied to the above-mentioned matching and error type discriminating circuit 3, position information and timing generating circuit 7.

The collation and error type discrimination circuit 3 collates the signal e with the data a from the circuit 1 in pit units, and responds to the error signal f,
An error type signal (a signal for discriminating between a dropout and a source) h is output.

On the other hand, the position information and timing generation circuit 7 outputs the signal e.
(Position information start pulse and clock pulse) for obtaining position information of each pit on the optical disk 5 based on the
Output g.

The output error signal and pulse g are supplied to the intra-sector position information generating circuit 8. Using the pulse g, the circuit 8 uses the intra-sector position information signal i representing the position in the sector of the pit corresponding to the signal f (that is, the pit having the dropout or the well) among the pits on the optical disk 5. Is output. The circuit 8 outputs an address signal j specifying a memory address corresponding to each pit on the optical disk 5 using the pulse g. These circuits
3,7,8 correspond to the matching detection means.

The error type signal h and the intra-sector position information signal i corresponding to the error position are given to the data input of the two-port memory 9. The address signal j is applied to an addressing input of the memory 9 via the OR circuit 10. The memory 9 stores the signals h and i at the address specified by the signal j.

The editing processing unit ED is also used for the address designation input of the memory 9.
An address signal K is also supplied from T via an OR circuit 10.
And is given to the editing processing device EDT, subjected to appropriate editing processing and stored in the memory MEM.

Next, an example of the inspection operation in this inspection apparatus is described in the second section.
This will be described with reference to the drawings.

First, positioning to a track on the optical disk 5 to be inspected is performed (step 101 in FIG. 2). And
Data a is generated from the circuit 1, and the data a is recorded on the track to be inspected on the optical disk 5 by the circuit 4 (step 102 in the figure).

When the recording is completed, the positioning to the track to be inspected is performed again (step 103 in the figure). Then, the data a recorded on the track is sequentially read out, the data a is generated again from the circuit 1, and the circuits 3, 7, 8 are generated by using the signal e obtained based on the read and the data a from the circuit 1. To obtain the signals h and i (step 104 in the figure).

The signals h and i obtained in this way are stored in the memory 9 (step 105 in the figure). Then, the signals h and i stored in the memory 9 are appropriately read out and classified / edited (step 10 in FIG.
6). For example, when the storage of the two-port memory 9 is saturated (the inspection results are recorded in pit units, the saturation is likely to be reached with a limited capacity), the storage contents are transferred to the editing and processing apparatus EDT, where they are dropped out. And extract only the error type information and position information corresponding to the source,
This information is stored in memory with the data compressed in this way.
Store in MEM.

In this way, the position of the optical disk 5 where the dropout or the well is present is accurately detected in pit units in the form of a signal hi, and the inspection result data is compressed in the pit unit inspection. Can be memorized.

〔The invention's effect〕

As described above, according to the present invention, for an optical disk or a magneto-optical disk, the position where a dropout or a well is present can be detected in pit units, so that the error position can be detected with high accuracy. This has an excellent effect that it is possible to determine whether the error is a dropout or a well. Further, since the error identification signal and the error position specifying information are stored in pairs in the storage means, the error position and the error type can be specified without storing all the read data of the disk. This provides an excellent effect that the inspection result can be stored in a compressed form.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of an inspection apparatus according to the present invention, and FIG. 2 is a flowchart showing an example of an inspection operation in the inspection apparatus. 1 ... pit pattern generation circuit, 2 ... recording control circuit, 3 ...
... Verification and error type discrimination circuit, 4 ... Laser recording drive circuit, 5 ... Optical disk, 6 ... Amplifier and reproduction circuit, 7 ... Position information and timing generation circuit, 8 ... Sector position information generation circuit, 9 …… 2 port memory, 10 …… OR circuit

Claims (1)

(57) [Claims] 1. An apparatus for inspecting an optical disk or a magneto-optical disk for the presence or absence of dropout and spout at each pit position, comprising: pit pattern data for inspection comprising pit pattern data for inspection at each pit position. Generating means for generating pit pattern data generated by the generating means on a disk to be inspected; reading means for reading pit pattern data recorded on the disk by the recording means; and the reading means The pit pattern data read from the pit pattern data and the pit pattern data generated from the generating means are collated on a pit basis, and an error signal and the error are generated at the dropout and the source corresponding to the pit having the dropout or source. Output an error identification signal for identifying the Combining means, means for outputting error position specifying information for specifying a pit position where a dropout or a well exists based on the error signal, and storage means for storing the error identification signal and the error position specifying information in pairs. An optical disk inspection device, comprising: