JPH03192578A - Optical disk device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Summary] Regarding an optical disk device that detects errors and corrects errors when reading and writing data from an optical recording medium, errors caused by dust and the optical disk medium are determined depending on the ratio of the number of error corrections to the number of read commands. The purpose of the present invention is to provide an optical disk device that improves read/write quality by identifying errors caused by defects in the optical recording medium and issuing cleaning instructions. An optical disk device comprising an error detection means for detecting an error and an error correction means for correcting the detected error, the read number command counting means for counting the number of read commands for reading data from the optical recording medium, and the error correction means. an error correction number counting means for counting the number of error corrections in which an error has been corrected; a calculation means for calculating a ratio of the number of error corrections to the number of read commands; and a calculation means for determining that the calculated ratio has exceeded a certain value. and a discriminating means for outputting a cleaning instruction signal.

[Industrial Application Field] The present invention relates to an optical disk device that detects errors and corrects errors when reading and writing data from an optical recording medium.

In recent years, optical disk devices that have a large capacity and can perform high-speed access have come into use. However, since the read and write quality of optical disk devices is not as good as that of magnetic disk devices, when an error occurs, an error correction means is installed to detect the error and correct the detected error. . Here, dust may accumulate on the optical disc medium or the lens of the optical disc device, making reading impossible. In these cases, the writing quality deteriorates, further increasing the impossibility of reading and increasing the frequency of errors.

Therefore, in order to improve read/write quality, it is necessary to distinguish errors caused by such dust from errors caused by normal medium defects and perform error correction.

[Prior Art] As a conventional optical disk device, there is one shown in FIG. 3, for example.

In FIG. 3, reference numeral 1 denotes an optical disk medium, and the optical disk medium 1 is rotationally driven by a spindle motor 2. As shown in FIG.

3 is a laser pickup;
reads data from or writes data to the optical disc medium 1. 4 is a signal reproducing/recording section, and the signal reproducing/recording section 4 reproduces data from the laser pickup 3 or instructs the laser pickup 3 to record data according to instructions from the microprocessor 5.

When the microprocessor 5 receives a read command from the host computer 6, it instructs the laser pickup 3 to read data. The laser pickup 3 reads data from the optical disk medium 1, and the read data is reproduced by the signal reproducing/recording section 4 and sent to the host computer 6 via the microprocessor 5.

An error detection circuit 7 is provided in the signal reproducing/recording section 4.
The error detection circuit 7 detects data errors. When an error is detected by the error detection circuit 7, it is corrected by the error correction circuit 8. Error correction circuit 8 is controlled by microprocessor 5. Note that 9 is a medium detection circuit.

[Problems to be Solved by the Invention] However, in such conventional optical disc devices, when an error is detected, the error is corrected by the error correction circuit, but if the error is detected on the optical disc medium or Since it is not possible to distinguish whether the error is due to dust accumulated on the lens or a normal defect in the optical disk medium, it is not possible to issue instructions to properly clean the optical disk medium or lens when the error is caused by dust. However, there was a problem in that read/write quality could not be improved.

The present invention has been made in view of these conventional problems.The present invention distinguishes between errors caused by dust and errors caused by defects in the optical disk medium based on the ratio of the number of error corrections to the number of read commands, and issues a cleaning instruction to read the data. An object of the present invention is to provide an optical disc device that improves write quality.

[Means to solve the problem] FIG. 1 is a diagram explaining the principle of the present invention.

In FIG. 1, 16 is an error detection means for detecting an error that occurs when reading or writing data from the optical recording medium 11, 17 is an error correction means for correcting the detected error, and 19 is an error detection means for detecting an error that occurs when reading or writing data from the optical recording medium 11. read count instruction counting means for counting the number of read instructions to read;
21 is an error correction number counting means for counting the number of times the error is corrected by the error correction means 17; 22 is a calculation means for calculating the ratio of the number of error corrections to the number of read commands; 13 is an error correction number counting means for calculating the ratio of the number of error corrections to the number of read commands; The determination means outputs a cleaning instruction signal upon determining that the cleaning instruction signal has reached the value of .

[Operation] In the present invention, the calculation means calculates the ratio between the number of read commands counted by the number of read commands counting means and the number of error corrections counted by the number of error corrections counting means, and when the ratio reaches a certain value or more. When the determining means determines that this has occurred, it outputs a cleaning instruction signal for the optical recording medium or lens.

In other words, when the ratio exceeds a certain value, the frequency of errors increases, so such errors are not caused by normal defects in the optical recording medium, but are caused by dust accumulated on the optical recording medium or lens. It determines that it is an error and issues a cleaning instruction signal.

Therefore, by cleaning the optical recording medium or the lens, errors caused by dust can be prevented and read/write quality can be improved.

[Example] Embodiments of the present invention will be described below based on the drawings.

FIG. 2 is a diagram showing an embodiment of the present invention.

In Figure 2, 11 is an optical disk medium (optical recording medium)
The optical disc medium 11 has an information recording surface on, for example, a plastic substrate, and data is recorded on the information recording surface. Reference numeral 12 denotes a spindle motor, and the spindle motor 12 rotates the optical disk medium 11 according to instructions from a microprocessor (discriminating means) (hereinafter referred to as MPU) 13 .

Reference numeral 14 denotes a laser pickup. The laser pickup 14 includes an optical system such as a lens and a drive system, and reads data from or writes data to the optical disc medium 11.

15 is a signal reproducing/recording section, and the signal reproducing/recording section 15 is M
Based on instructions from the PU 13, data from the laser pickup 14 is reproduced or the laser pickup 14 is instructed to record data.

An error detection circuit (error detection means) 16 is provided in the signal reproduction/recording section 15, and the error detection circuit 16 detects the occurrence of a data error.

17 is an error correction circuit as an error correction means;
When the error detection circuit 16 detects an error, the error correction circuit 17 corrects the error according to instructions from the MPU 13. 18 is a medium detection circuit that detects whether or not the optical disk medium 11 is installed, and the medium detection circuit 18 detects the installation of the optical disk medium 11 and outputs MPtJ1.
Report to 3.

Reference numeral 19 denotes a first counter as means for counting the number of read commands.
The number of read commands given to the PU 13 is counted. A second counter 21 serves as a means for counting the number of error corrections, and the second counter 21 counts the number of error corrections that the MPU 13 instructs the error correction circuit 17 to perform error correction.

22 indicates the number of read commands from the first counter 19 and the second
This is an arithmetic circuit (arithmetic means) into which the number of error corrections from the counter 21 is input, and the arithmetic circuit 22 calculates the ratio of the number of error corrections to the number of read commands.

23 is an error rate constant memory, and error rate constants are stored in advance in the error rate constant memory 23. 24 is a comparison circuit into which the error rate constant from the error rate constant memory 23 and the ratio from the arithmetic circuit 22 are input; the comparison circuit 24 compares the error rate constant and the ratio and outputs the comparison result to the MPU 13. Based on the comparison result from the comparison circuit 24, the MPU 13 outputs a cleaning instruction signal to the host computer 20 when the ratio exceeds the error rate constant.

Next, the operation will be explained.

When the host computer 20 gives a read command to the MPU 13, this read command is counted by the first counter 19. The number of read commands counted by the first counter 19 is output to the arithmetic circuit 22.

On the other hand, when an error is detected by the error detection circuit 16, M
The error correction circuit 17 corrects errors according to instructions from the PU 13, and the number of error corrections is counted by the second counter 21 and output to the arithmetic circuit 22. The ratio of the number of error corrections to the number of read commands is calculated by the calculation circuit 22, and the ratio calculated by the comparison circuit 24 is compared with the error rate constant from the error rate constant memory 23. The comparison result of the comparison circuit 24 is output to the MPU 13.
3 outputs a cleaning instruction signal to the host computer 20 when the ratio exceeds the error rate constant.

This cleaning instruction signal causes the optical disk medium 11 to
Or clean the lens of the laser pickup 14. That is, when the ratio exceeds the error rate constant,
Dust accumulates on the optical disk medium 11 or the lens, making it impossible to read, which deteriorates the writing quality, which further promotes the impossibility of reading and increases the frequency of errors. Errors not due to normal defects in
It is determined that the error is caused by dust.

Since the optical disc medium 11 or the lens is cleaned after detecting errors caused by dust in this manner, errors caused by dust can be prevented and read/write quality can be improved.

[Effects of the Invention] As described above, according to the present invention, the ratio of a fixed number of errors to the number of read commands is calculated, and when the ratio exceeds a certain constant, it is determined that the detected error has occurred in the optical disk medium or lens. Since the error is determined to be caused by accumulated dust and an instruction to clean the optical disk medium or lens is issued, read/write quality can be further improved.

[Brief explanation of drawings]

FIG. 1 is a diagram explaining the principle of the present invention, FIG. 2 is a diagram showing an embodiment of the present invention, and FIG. 3 is a diagram showing a conventional example. In the figure, 11... optical disk medium (optical recording medium), 12...
Spindle motor, 13... Microprocessor (discrimination means), 14...
- Laser pickup, 15... Signal reproducing recording section, 16... Error detection circuit (error detection means), 17.
...Error correction circuit (error correction means), 18...Medium detection circuit, 19...First counter (read command number counting means) 2
0...Host computer, 21...Second counter (error correction number counting means) 2
2... Arithmetic circuit (arithmetic means), 23... Error rate constant memory, 24... Comparison circuit. + Kyumeka's n, Mi! The 1st picture of the quality decoy is 1911 and the 1911 of the heather Bonmei and the 1st month of Ho-cho-ki and the 1st 11th and +V decoy 3F! 2I

Claims (1)

[Claims] In an optical disk device that reads and writes data from an optical recording medium (11) and includes an error detection means (16) for detecting an error when an error occurs in the data and an error correction means (17) for correcting the detected error. , a read number command counting means (19) for counting the number of read commands for reading data from the optical recording medium (11), and an error correction number for counting the number of error corrections performed by the error correction means (17). a counting means (21), a calculation means (22) for calculating the ratio of the number of error corrections to the number of read commands, and a determination unit for determining that the calculated ratio has reached a certain value or more and outputting a cleaning instruction signal. An optical disc device characterized by comprising means (13).