JPH02128326A - Optical recording and reproducing device - Google Patents

Abstract

PURPOSE:To always obtain an optimum recording condition even against a recording sensitivity difference of an optical recording and reproducing medium and a variation of an ambient temperature and to improve the quality and the reliability of a recorded signal by detecting and setting an optimum recording light quantity immediately before recording an information signal. CONSTITUTION:This device is provided with an RF amplifier 1, peak detectors 2, 3, an error amplifier 4, an A/D converter 5, an input port 6, an optical head 7, an output port 8, a RAM 9, a ROM 10, a CPU 11, a D/A converter 12, a recording amplifier 13, a magneto-optical disk 14 and a magnetic field generating device 15. In this state, immediately before recording an information signal, a signal is recorded to a track for recording the information signal or its adjacent track, while varying stepwise or continuously the light emission quantum of a laser light source, and from the reproduced signal, the light emission quantum of the laser light source being optimum for recording is detected and set. In such a way, by a result of detection, the light emission quantity of the laser light source at the time of recording is set and the recording light quantum being optimum for a recording and reproducing medium is always obtained, and the quality and the reliability of a recorded signal are improved.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to an optical recording/reproducing device.

[Conventional technology]

In conventional optical recording and reproducing devices, the amount of light emitted by a laser light source when recording an information signal is a fixed value set in advance.

[Problem to be solved by the invention]

The above-mentioned conventional optical recording and reproducing apparatus has a problem in that it is not possible to obtain a light emission amount of a laser light source that corresponds to changes in the optimum recording light amount due to differences in recording sensitivity of optical recording and reproducing media, changes in ambient temperature, etc. Ta.

[Means to solve the problem]

The present invention has been made in order to improve the above-mentioned conventional problem. Immediately before recording an information signal, a laser light source emits light in a recessed or continuous manner on the track where the information signal is recorded or on the track near the track. It has a recording/reproducing means that records a signal while changing the amount, and detects and sets the optimum light emission amount of the laser light source for recording from the reproduced signal.

[Effect]

In the present invention, the amount of light emitted from the laser light source during recording is set based on the detection result, so that the optimum amount of recording light for the recording/reproducing medium can always be obtained.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of an optical recording/reproducing apparatus according to the present invention. In the same figure, 1 is an RF amplifier, 2
, 3 is a peak detector, 4 is an error amplifier, 5 is an A/D converter, 6 is an input port, 7 is an optical head, 8 is an output port, 9 is a RAM, 10 is a ROM, 11 is a CPU, 1
2 is a D/A converter, 13 is a recording amplifier, 14 is a magneto-optical disk, and 15 is a magnetic field generator.

FIG. 2 is a detailed diagram showing the structure of the optical head 7. As shown in FIG. In the figure, 21 is a semiconductor laser, 22 is a collimating lens, 23 is a beam shaping prism, 24.25 is a polarizing beam splitter, 26 is a condensing lens, 2T is a knife, 28 is a servo signal photodetector, and 29 is a condenser. lens, 3
0 is an information signal photodetector, 31 is a coil, and 32 is an objective lens.

Next, the operation will be explained.

In FIG. 1, recording is performed on determined tracks on a magneto-optical disk 14 using a preset recording current. After that, playback is performed immediately. The reproduced signal output from the RF amplifier 1 has its DC component removed by a capacitor, and is output to peak detectors 2m and 2b. The peak detectors 2m and 2b detect positive and negative peaks of the reproduced signal, and input the positive peaks as they are and the negative peaks after inverting their polarity and inputting them to the error amplifier 4. If the recording current is optimal, the input signal level of the error amplifier 4 will be equal and the output will be GND. If the recording current is not optimal, the error amplifier 4 outputs a positive or negative voltage. The output of the error amplifier 4 is converted into digital data by the A/D converter 5 and output to the data bus 9 through the input port. The CPU 11 outputs data to the output port 8 so that the input data is given the GND level. After the data is converted to analog by the D/A converter 12,
It is output to the recording amplifier 13 to provide a recording current.

In this example, the data to the D/A converter 12 is changed in 10 steps during the recording operation of 1 track (16.7 msec), and in the next 16.7 msec, the data is synchronized with the timing at which the data is changed. Data is read from the A/D converter 5 one after another at the appropriate timing. The changed data is stored in RAM
9, and the data when the data from the A/D converter 5 reaches the GND level (80H) is fixed data, and this value is used from the next recording operation. A/
If the data from the D converter 5 does not reach 80H, another recording operation is performed with the data that gives data closest to 80H reduced in the range of change. The optimum recording current can be obtained in the above manner.

〔Effect of the invention〕

As explained above, the present invention detects and sets the optimum recording light intensity immediately before recording an information signal, thereby ensuring optimum recording at all times even when there are differences in recording sensitivity of optical recording and reproducing media and changes in ambient temperature. the conditions obtained and the quality of the recorded signal,
This has the effect of improving reliability.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of an optical recording/reproducing apparatus according to the present invention, and FIG. 2 is a configuration diagram of the optical head in FIG. 1. 1...ψ-RF amplifier, 2a, 2b...peak detector, 3...inverting amplifier (Av=-1), 4@-...
Error amplifier, 5...A/D converter, 6-...
・Input port, 7...Optical head, 8...Output port, 9...RAM, 10..., @ROM
, 1 1 ・ Φ dispute CPU, 1
2 ・ Φ ・ ・D/A: l inverter, 13...
・Recording amplifier, 14...Magneto-optical disk, 15...
...Magnetic field generator, Book 21...Semiconductor laser, 22.
... Collimating lens, 23... Beam shaping prism, 24, 25... Fist/polarizing beam splitter, 26
...Condensing lens, 27...φ Naifetsuji, 28
・・e・Servo signal photodetector, 29・・・Condensing lens, 30・・・Information signal light detection! , 31... Coil, 32--... Objective lens.

Claims (1)

[Claims] In an optical recording and reproducing apparatus that records or reproduces information by irradiating an optical recording and reproducing medium with a light beam emitted from a laser light source, immediately before recording the information signal, a staircase is installed on the track where the information signal is to be recorded or on a track in the vicinity thereof. Recording a signal while changing the amount of light emitted from the laser light source at a specific time or continuously, reproducing the recorded signal at the same time or immediately after, and detecting and setting the amount of light emitted from the laser light source that is optimal for recording from the reproduced signal. 1. An optical recording and reproducing device characterized by having a recording and reproducing means.