JPH07101511B2 - Information recording / reproducing device - Google Patents

Description

TECHNICAL FIELD The present invention relates to control of recording or reproducing conditions of an information recording / reproducing apparatus.

[Prior art]

Conventionally, in this kind of device, the recording power of the laser, the recording bias magnetic field strength, the slice level for binarization, etc.
It was fixed or set automatically every time a recording medium was attached to the device. However, DRAW (Direct Read After Write)
In the case of the optical disc of the type, since the erasing is impossible, the automatic adjustment of the recording power is limited because the recording area and the number of recordings are limited. Further, the size of the pit to be recorded varies depending on the medium due to variations in the sensitivity of the recording medium, which causes an error in recording / reproducing information. In addition, since the erasable magneto-optical disk and the like are automatically set for each mounting, it takes extra time until the mounting actually records and reproduces data.

〔Purpose〕

The present invention has been made in view of the above points, and records measurement data on a recording medium, reproduces the measurement data, and adjusts the recording / reproducing means so that the reproduced measurement data satisfies a predetermined condition. The operation value is determined, and the determined appropriate operation value is recorded in a predetermined area of the recording medium. Further, the appropriate operation value data of the recording / reproducing means already recorded on the recording medium is read out to operate the recording / reproducing means. By determining the conditions, optimum recording conditions and reproduction conditions can be quickly set for various recording media, and as a result, data can be accurately recorded on the recording medium or data can be accurately recorded from the recording medium. The purpose is to improve the reliability of the device.

〔Example〕

 An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of an information recording / reproducing apparatus to which the present invention can be applied.

Reference numeral 1 is a magneto-optical disk medium for recording information, 2 is an optical pickup for recording or reproducing data on the recording medium 1, 3 is an electromagnet for applying a bias magnetic field to the recording medium 1 at the time of recording, and 4 is an optical pickup. A variable gain amplifier 5 that amplifies the information signal reproduced by 2 to a required level, and a reproduction information signal 5 amplified by the variable gain amplifier 4 into two binary signals of "0" and "1". A level comparator (comparator) for conversion, 6 is a duty ratio detection circuit for detecting a duty ratio of a binarized signal, 7
Is a first A / D converter for converting changes in the duty ratio detected by the duty ratio detection circuit 6 into digital data, and 8 is an amplitude detector for rectifying the output of the variable gain amplifier 4 and detecting the amplitude of the reproduction output. , 9 are the amplitude detectors 8
Second to convert analog data from the digital to digital data
A / D converter, 10 is a D / A converter that gives the threshold level of the comparator 5 as an analog value, 11 is a laser drive circuit for driving the semiconductor laser inside the optical pickup 2, and 12 is these A controller that controls the operation of each unit, and 13 is a switch that selects a slice level.

Next, the operation of this apparatus will be described with reference to FIG. Since the recording / reproducing process uses a known method, the description thereof is omitted here. 2 to 4 are flowcharts of the operation of the present invention, which will be described below.

First, when the disk is mounted on a turntable (not shown), as shown in step 52, the gain of the amplifier 4 is set to the disk setting value of the average reproduction level, and the slice level for binarization is set to The value when the ideal signal is reproduced and the peak power of the laser at the time of writing are set in advance to the average disk value. The slice level select switch 13 is connected to the b side. Here, an index area is preset in the innermost circumference (or outermost circumference) of the disk 1 and a data area corresponding to a reproduction signal level, a data area corresponding to a bias magnetic field, and a slice level are set in this area. , And a data area corresponding to the recording peak laser power are set, and an area for recording information indicating whether the disk has been used once or not is also set. In steps 53 and 54, the data in the index area is taken into an information recording / reproducing device (hereinafter referred to as a disk drive), and the disk is a new disk or a disk which has been used once, that is, a slice level, a laser in the index area. power,
It is judged whether or not each data corresponding to the bias strength and the reproduction level is already written.

If the disk is a completely new disk, a signal having a constant frequency with a duty ratio of 50% is recorded in a predetermined area (hereinafter referred to as a tuning area) on the disk (step 55). Next, in steps 56 and 57, the signal recorded in this tuning area is reproduced, and the duty cycle of the reproduced signal is measured. Here, in FIG. 1, the threshold level 21 of the binarization circuit is set in advance to a level of 50% when an ideal signal is input, so that the output of the duty ratio detection circuit 6 is the reproduced signal. A signal corresponding to the duty ratio of is obtained. This value is A /
The digital signal is converted by the D converter 7 and sent to the controller 12.

When it is determined in the controller that the duty ratio is not 50%, it is determined whether the recording power is high or low according to the duty ratio (step 58). 50% duty ratio
In the following cases, that is, when the laser power is small, the laser power is increased by a certain amount, and when the duty ratio is 50% or more, that is, when the laser power is too large, the laser power is decreased by a certain amount. Also, it is detected here whether the laser power has reached the limit of the control range. If it is not the limit, the signal in the tuning area is erased and the same process is repeated again with new laser power (steps 59 to 63). .

When the laser power reaches the control limit, the controller 12 first determines whether the laser power is maximum or minimum. If the laser power is maximum, the recording bias magnetic field is decreased by a certain amount, and if it is minimum, it is increased (step 64). 66), the bias magnetic field is changed by a fixed amount within the control range, and recording / reproduction is performed in the tuning area until the duty ratio reaches 50% or the bias reaches the control range limit (step). 64-71-2). When both the laser power and the recording bias magnetic field have reached the limits of the control range, both the laser power and the recording bias magnetic field are written in the tuning region at the limit values. Then switch 13
Is connected to the a side (step 72) and the signal is reproduced (step 73). At this time, the output of the duty ratio detector 6 is fed back and becomes the threshold value of the binarization circuit 5.
Here, the duty cycle detector forms a kind of integrator, detects the DC component of the binary signal, and detects the duty ratio from the value. By setting the output of the duty ratio detector 6 so that the duty ratio becomes 50% when this closed loop is formed, even if a distorted signal is input to the input, the threshold is automatically set to 50%. It changes so that the output can be obtained (step 73). This threshold value is taken into the controller 12 by the A / D converter 7 (step 7
4) Set the slice level and connect the switch 13 to the b side (step 75). The slice level data is converted to an analog value by the D / A converter 10 and input to the threshold value input of the binarization circuit 5. Added (step 7
6). Next, after the duty ratio of the reproduced signal reaches 50%, the analog reproduced signal from the preamplifier is detected by the amplitude detector 8
Inside the rectifier, it rectifies and smoothes, detects the amplitude of the reproduced signal, converts the amplitude information into digital data by the A / D converter 9, and imports it into the controller 12 (step
77), based on the amplitude data, the controller 12 sends the gain data to the variable gain amplifier 4 so that the reproduction signal has a preset amplitude and keeps the reproduction signal level constant (step 78).

As mentioned above, the recording peak laser power obtained so far,
The four types of data of recording bias magnetic field strength, slice level data, and dyne data are recorded in the memory in the controller 12 at the completion of each detection operation, and when all four data are collected, the index area of the disk is recorded. It is recorded in each area (step 79).

If the disk has already been used once in the new disk judgment operation of step 54, that is, if the above-mentioned four data have already been written, the index area of the disk is reproduced and the laser power, bias magnetic field, and slice level are reproduced. , Read each gain data (Step 8
0), based on the data read by the controller 12, each value is set (step 81) to prepare for normal operation.

Although the magneto-optical disk has been described in the above-mentioned embodiment, the same operation can be performed on the optical disk only with no data on the bias magnetic field.

[Effect]

As described above, according to the present invention, the measurement data is recorded on the recording medium, the measurement data is reproduced, and the appropriate operation value of the recording / reproducing means is set so that the reproduced measurement data satisfies the predetermined condition. Is determined, and the determined proper operation value is recorded in a predetermined area of the recording medium. Further, the proper operation value data of the recording / reproducing means already recorded on the recording medium is read out, and the operating condition of the recording / reproducing means is determined. By deciding,
Data can be accurately recorded on the recording medium in a state adapted to the characteristics of the recording medium, or data can be accurately reproduced from the recording medium.

Furthermore, the range of specially made recording media that can be used is widened, and it is possible to contribute to improvement in productivity of recording media and reduction in cost.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of an information recording / reproducing apparatus to which the present invention can be applied, and FIGS. 2 (a) to 2 (c) are operation flow charts of a controller.

Claims (2)

[Claims] 1. A recording / reproducing device for recording information on a recording medium or reproducing information from the recording medium, recording data for measurement on the recording medium by the recording / reproducing device, and reproducing the recorded measurement data. First control means for determining proper operation value data of the recording / reproducing means such that the reproduced measurement data satisfies a predetermined condition, and the proper operation value data determined by the first control means is recorded / reproduced. Second control means for recording in a predetermined area of the recording medium by means, and reproducing the proper operation value data recorded in the recording medium by the second control means by operating the recording / reproducing means under predetermined operation conditions. And a third control means for determining the operating condition of the recording / reproducing means based on the reproduced proper operating value data. 2. The information according to claim 1, wherein the first control means and the second control means operate when proper operation value data is not recorded on the recording medium. Recording and reproducing device,