JPS63166025A - Optical information recording and reproducing device - Google Patents

Abstract

PURPOSE:To improve an information recording rate, by deciding the normal/ defective condition of the recording state of information at every constant period by comparing the reproducing signal of a signal recorded by 0th order light with a delayed information signal to be recorded, and performing the recording of the information as recording the above result. CONSTITUTION:Light flux emitted from a light source 1 is divided into three light flux of the 0th order light and + or - 1st order light in total by a diffraction grating 3, and those light flux are projected on the same information track on an information recording medium 7 as three light spots 13a-13c, and the reflected light of each spot is detected by photodetectors 10a-10c respectively. Out of those spots, the 0th order light is used in the recording and reproduction of the information. Also, at the time of recording the information, the difference of the output signals by the + or - 1st order light detected by the photodetectors 10a and 10b is taken, and the signal is compared with the delayed information signal, and the normal/defective condition of the information is decided, and the result is recorded appropriately. Those operations can be performed continuously by a single light source. In such a way, it is possible to improve the information recording rate.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an optical information recording/reproducing device that can realize an improvement in information recording rate using an inexpensive optical head.

(Prior Art) Conventionally, in an optical information recording and reproducing device that optically records and reproduces information on a recording medium, a certain unit of data is used to improve the reliability of multiplication information recorded on the medium. Every time information is recorded, the recorded portion is reproduced to evaluate the recorded state of the information. At this time, if there is a significant omission in the recorded information, measures are taken such as recording the same information again at another location on the medium.

(Problem to be solved by the invention) However, when performing such table operations, for example, when using an optical head of the type that records and reproduces information by irradiating a single radar beam onto the medium, the information When recording, recording and reproducing operations must be performed alternately, which causes a problem in that the recording rate is significantly reduced. Furthermore, when using an optical head that records and reproduces information using, for example, two Rade light sources, the recording process can be performed by following the Rade light of the recording layer with the Rade light for reproduction. By performing the playback operation at the same time as the operation, it is possible to evaluate the recording state of information in real time. However, even in this case, since the Raded light emitted from the two Raded light sources passes through the same objective lens and is irradiated onto the medium, it is troublesome to adjust the position of each Raded light source, and an expensive Raded light source is required. It requires two light sources, and there is also a problem in terms of cost.

An inexpensive optical information recording/reproducing apparatus that solves these problems and has a high recording rate is desired in the field of continuous recording of large amounts of information such as audio data or image data.

Therefore, the present invention solves the problems of the conventional device as described above, improves the information recording rate using an inexpensive optical head, and provides an optical head suitable for continuously recording a large amount of information. The purpose is to provide an information recording and reproducing device.

(Means for Solving the Problem) The problem with the prior art described above is that a diffraction grating is provided between a light source and an information recording medium, and the light beam emitted from the light source is converted into zero-order light and It is equipped with an optical head that divides the beam into three beams of ±1st order light, irradiates these three beams onto the same information track on the information recording medium, and detects each reflected beam from the medium with a light receiving element. an information recording and reproducing apparatus according to the present invention; means for comparing the reproduced signal with a delayed version of the information signal given to be recorded and determining whether the recording state of the information is good or bad at regular intervals; This problem can be solved by an optical information recording/reproducing device that is characterized by recording information while recording results.

(Function) According to the configuration of the present invention described above, the light beam emitted from the light source is divided by the -diffraction grating into a total of three light beams, the 0th-order light and the ±1st-order light, and these light beams are divided into three light switches. The same information track on the information recording medium is irradiated with the light, and the reflected light from each switch is detected by a light receiving element. Of these switches, the zero-order light can be used for recording and reproducing information. Also, when recording this information, the difference between the output signals detected by the light receiving element and the 9±1st order light is taken, and this signal is compared with the information signal to be recorded, which is to be delayed, and the signal is recorded. The quality of the information is judged. The result of this judgment is then recorded as appropriate. These operations can be performed continuously using one light source, thereby reducing the cost of the optical head and
Moreover, an improvement in the information recording rate is realized.

(Example) An example of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic diagram showing the configuration of an optical system of an optical head according to this embodiment and a light switch irradiated onto an information track of an information recording medium.

In FIG. 1, a light beam emitted from a light source 1 such as a semiconductor radar and diffused into a parallel light beam is made into a parallel light beam by a collimator lens 2, and is split into three light beams, 0th-order light and ±1st-order light, by a diffraction grating 3. . The divided light flux passes through the polarization beam sinter 4, is converted from linearly polarized light to circularly polarized light by the r/4 plate 5', passes through the objective lens e6, and is converted into the same information on the information recording medium 7. Main strip 4 in the center on track 11
The lights are irradiated on both sides of the lights 13b and 13m as sub lights 13m and 13c.

Here, the arrow in FIG. 1 indicates the moving direction of the information recording medium 7, and the medium 7 is moved in the direction of the arrow by a drive device (not shown), and the main switch 4 is moved according to predetermined information. 1
3b irradiation causes information to appear on the information track 11) 14
is recorded. Note that, as described above, the sub-slots 13m and 13b are arranged to be about the length of the main slot 13eK, with the sub-slot 13m preceding the main slot 13a.

Therefore, the sub spot 13m always illuminates the unrecorded portion of the information track 11, and the sub spot 13b always illuminates the recorded portion of the information track 11.

Furthermore, the light intensity of these sub-spots 13m and 13b is such that even when the light intensity of the main spot 13e is not increased to the recording level, the sub-slits 13m and 13b cause a change in the information recording medium 7. This can be done by setting the diffraction grating 3.

Next, the three light beams irradiated onto the information recording medium 7 are each reflected on the surface of the medium 7, and are again reflected by the objective lens e.
6. The beam passes through the r/4 plate 5 and enters the polarization beam sinter 4. Next, the optical path is changed to a right angle by the polarizing beam sinter, and the beam is focused by the condensing lens 8 and enters the cylindrical lens 9 . The three reflected beams are given astigmatism by this cylindrical lens, and then a photodetector 100 and three light receiving elements 10m, 10b, 10e
Detection is made in each of the following. 10 of these photodetectors
Since the reflected light from the sub-spot 131 is received at &, the light receiving element 10m detects a change in the amount of light obtained by multiplying the change in the amount of light due to the recording/reference pulse by the reflectance from the unrecorded portion of the information track 11. In addition, since the light receiving element 10b receives the reflected light from the sub-slit 13b, the mosquito light receiving element 10b receives a change in reflectance due to the change in the light amount due to the recording/4 lus and the non-reflection of the information pit 14 of the information track 11. The change in light intensity multiplied by .

The good signals detected in this way are processed by the signal processing circuit shown in FIG. Drawing 2, the light receiving element 10
A subtracter 15 calculates the difference between the signals detected at m and 10b and h. Next, this signal difference is compared with the base fjA voltage in the con/4 rake 16 and binarized. The output from this input 74 regulator 16 is sent to the data comparator 171.
The data comparator compares the recorded signal 18 delayed by the delay circuit 19 with the output signal from the comparator 16, and outputs an O signal depending on whether they match or do not match.
Or a signal of 1 is output. Then, this output is compared with the output state of the data comparator 17 for a certain fixed period in a state determiner 20, and is outputted as a check mark 21.

On the other hand, the reflected light from the main switch 13e is reflected from the light receiving element 1.
It is detected at 0c. This light-receiving element 10c is composed of a four-part light-receiving element.

Is each output of the light receiving element 10cO? The signal is processed by the signal generation circuit, and the focuser generates the signal 23. ) Luxar? It is converted into a signal and used for various controls.

The operation and effect of this embodiment will be explained in detail below with reference to various drawings. 3 is a diagram showing a recording signal system of a recording 7t-mat in an information recording medium recorded according to the configuration of the optical head shown in FIG. 1 and according to the signal processing circuit shown in FIG. 2; FIG. 2 is a waveform diagram formed by each part of the signal processing circuit shown in FIG. 2, and FIG. 5 is a recording operation sequence diagram in the signal processing circuit shown in FIG. 2. The following description will be made with reference to each figure, centering on FIG.

As shown in FIG. 5, when a recording command is issued during information recording, the optical head is moved to a predetermined information track, and an unrecorded portion on the information track IIK is detected. Next, on the information track 11h, a recording clock is pulled in by the famic header 2, and an address 27 and data 28 are recorded. With this ζ, the recording signal sequence in the information track 11 becomes as shown in FIG.

In FIG. 3, the f-lock header 26 is recorded in advance on the information track 1 when recording the information.
1 undistributed part is detected.

Then, at the same time as the recording of data 28 is completed, K is pressed.

By the signal processing circuit shown in FIG. 2, the recording state is determined by the state determiner 2°.

Furthermore, regarding the determination of the recording state of
I4 formed by each part of the signal processing 31 circuit shown in the figure
This can be explained using a pulse waveform diagram. In Figures 2 and 4, the output of the light receiving element 10m is information track 1.
Since this is due to the reflected light from the unrecorded area of 1, a pulse waveform matching the recorded pulse by the main switch 43e is obtained as shown in FIG. 4(1). On the other hand, the light receiving element 10
The output b is due to reflected light that is varied according to the recording state of the information track 11 recorded by the main spot 13c, and a pulse waveform as shown in FIG. 4(3) is obtained. In other words, the base pulse waveform shown in FIG. 4 (3) is
The signal shown in FIG. 4(1) is obtained as having been modulated by the recording signal on the information track 11 shown in FIG. 4(2). Next, the above Figure 4 (1) and (3)
) is input to the subtracter 15, the difference between the two signals is taken by the subtracter, and as a result, a /f pulse waveform as shown in FIG. 4 (4) is obtained. Furthermore, this signal all con/4
Conno 4 rate reperma at rate 16. When the waveform is concatenated at , a f pulse waveform as shown in FIG. 4 (5) is obtained. The signal output from the converter 16 thus obtained matches the signal shown in FIG. 4(2).

This means that the signal recorded on the information track IIK at the main spot 13c is output from the converter 16. However, the data comparator 17 determines whether or not the signal output from the Hun-9 register 16 matches the signal shown in FIG. 4(2), that is, the information signal to be recorded. A delay circuit 19 is connected to this data comparator 17, and the information to be recorded is delayed by the delay circuit, and the difference between the light receiving element 10a and the light receiving element 10b is recorded together with this delayed signal. The data comparator 17 compares the information signal with the reproduced information signal. The result of comparing these signals, that is, whether they match or not, is determined by the state determiner 20. If they match, a signal O, for example, is recorded as a go od flag in the check flag 29 in FIG. 3, and the next data is recording is performed. If they do not match, the signal 1, for example, is recorded as a bad flag in the check flag 29, and the same address and data are recorded again in the next recording block, and the same operation is performed thereafter.

Therefore, according to the optical information recording and reproducing apparatus of this embodiment,
Recording of information to be recorded and determination of the quality of the recorded information can be performed continuously using one light source, and an improvement in the information recording rate can be expected.

Further, since the recording state determination result recorded in the check flag 29 of the information track 11 can be used for processing such as error correction during information reproduction, the reliability of the recorded signal is also improved.

It should be noted that the optical head used in the above embodiments is not intended to limit the present invention, and the optical head used in the above embodiment is not limited to the present invention. For information recording media with high recording sensitivity as shown in the figure, a polarizing beam smitter 4 is used.
It is also conceivable that a parallel plate half mirror 32 be used as a mirror to increase the utilization efficiency of the semiconductor radar and reduce the number of parts.

Furthermore, even if the subtracter 15 is replaced by a divider in the signal processing circuit of FIG. 2, the effect remains the same. Further, the embodiments of the present invention can be applied to information recording media 1 in which the reflectance changes depending on the recording state, for example, a phase change optical memory medium, but it can also be applied to an information recording medium 1 in which the reflectance changes depending on the recording state. The present invention can also be applied to information recording media of different formats. An example of the configuration of the optical head in this case is shown in FIG. 8, and an example of the configuration of the signal processing circuit is shown in FIG. Furthermore, in the embodiment of the present invention, the three light spots are set to be arranged in a straight line along the information track, but as shown in FIG. They may be arranged in a staggered manner. In this case, by peak-holding the detection output of the reflected light from each sub-spot and taking the difference, a sit-track therme signal can be obtained from the sub-spots during recording, and a stable track therme I can be obtained.

(Effects of the Invention) As described above, according to the optical information recording and reproducing apparatus of the present invention, even if there is only one light source, information can be recorded and the quality of the recorded information can be continuously determined. Therefore, an improvement in the information recording rate can be achieved. Therefore, according to the present invention, a large amount of information can be continuously recorded using a low-cost optical head.

Further, according to the present invention, the reliability of the recorded signal is also improved because the determination result of the recording state can be used for processing such as error correction during information reproduction.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing the configuration of the optical system of the optical head used in the optical information recording/reproducing apparatus of the present invention and a light spot irradiated onto the information track of the information recording medium, and FIG. 3 is a diagram showing the recording signal series of the recording format, FIG. 4 is a diagram of the f pulse waveform formed by each part of the signal processing circuit shown in FIG. 2, and FIG.
Recording operation sequence diagram in the signal processing circuit shown in the figure,
6 and 7 are schematic configuration diagrams showing modified examples of the optical head used in the present invention, and FIG. 8 is a schematic diagram showing a configuration example of an optical head used when the present invention is applied to, for example, a magneto-optical medium. FIG. 9 is a block diagram of a signal processing circuit used in the optical head shown in FIG. 8, and FIG. 10 is a schematic plan view showing another arrangement example of three divided light spots. 3... Diffraction grating, 9... Cylindrical lens, 1
0... Light receiving element, 11... Information track, 13a. 13b... Sub-slit, 13c... Main spot, 1
5...Subtractor, 16...Conno 4lator, 17...
- Data comparator, 19... Delay circuit, 20... Status determiner, 21... Check flag. Agent Patent Attorney Jo Taira Yamashita @Figure 1 Figure 3 Figure 5

Claims (1)

[Claims] A diffraction grating is provided between a light source and an information recording medium, and the light beam emitted from the light source is converted into zero-order light and ±1 by the diffraction grating.
splitting the secondary light into three light beams and irradiating these three light beams onto the same information track on the information recording medium,
An information recording and reproducing device comprising an optical head that detects reflected light from the medium with a light receiving element, the information recording and reproducing device records information using the zero-order light and detects the difference in reflected light due to the ±first-order light. means for reproducing the signal recorded by the zero-order light, and means for comparing the reproduced signal with a delayed information signal given to be recorded and determining whether the information recording state is good or bad at each fixed period. An optical information recording/reproducing apparatus comprising: an optical information recording/reproducing apparatus which records information while subsequently recording the determination result within the certain period of time.