JPH05303744A - Device for recording and reproducing optical information - Google Patents

Abstract

PURPOSE:To improve probability making a reproduction defect track repro-ducible by retry. CONSTITUTION:When a track becomes reproduction defect and the retry is performed, by reproducing by a recording light spot becoming the light quantity of an extent by which information is not recorded on an optical card 11 instead of a reproducing beam, the probability making the track reproducible is improved. Switching from a reproducing spot to the recording spot is performed by switching a selector 5 by the selective signal 44 of a data controller 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical information recording / reproducing apparatus for optically recording / reproducing information on a recording medium.

[0002]

2. Description of the Related Art In recent years, an optical information recording capable of recording and reproducing information on an optical recording medium (optical card, optical disk, etc.) by converging and irradiating a light beam. Playback devices have become widely used.

For example, in an optical information recording / reproducing apparatus (optical card recording / reproducing apparatus) using an optical card as a recording medium, an optical card having a plurality of tracks parallel to each other and information is optically transmitted to the optical card. The information recording / reproducing is performed by relatively moving the recording / reproducing optical head in the track direction.

In the optical card recording / reproducing apparatus, the optical card is reciprocally moved to record / reproduce information, so that there is a drawback that the reproducing speed cannot be made very high. For this reason,
It has been considered to increase the reproduction speed by reading a plurality of tracks at one time during reproduction (hereinafter referred to as multi-track read).

A conventional method of this multi-track read will be described below. FIG. 2 is a diagram showing an optical card. The optical card 11 has ID sections 12a and 12b in which information such as track addresses is recorded in advance, and a data recording section 13 for recording and reproducing data. There is.

FIG. 3 shows an example of a multi-track readable optical head, and FIG. 4 shows an image formation state on an optical card using this optical head. When enlarged, the optical card 11 is composed of a plurality of guide tracks 27, a plurality of tracks (e.g. 28, 29, 30) between the guide tracks, and data pits 31 recorded on each track, as shown in FIG. As shown, the vertically long reproduction light beam 32 illuminates a plurality of tracks.
The light image shown in FIG. 4 is formed on the light receiving elements 35 to 39 as shown in FIG. 5 via the optical system shown in FIG. (3)
The data of the track is read.

FIG. 8 shows the structure of a conventional device.
The respective outputs of the light receiving elements 35, 36, 37 are respectively amplified and current / voltage converted by the I / V conversion circuits 1, 2, 3 and binarized by the binarization circuits 6, 7, 8, respectively. The data is demodulated by the data demodulation circuit 9. Then, each demodulated data is processed by the data controller 10 and output to the host computer 34 as reproduction data.

[0008]

However, in the multi-track readable optical head, since the reproducing beam 32 has an expanded illumination range, the reproducing optical beam for reproducing only one track is different from the conventional reproducing light beam. For example, the amount of light is about 1/100. This is inevitably generated because what is conventionally irradiated as one spot is expanded in a plane and then irradiated. Although the attenuation value varies depending on the number of tracks to be read, it is an example in the case of using a semiconductor laser having the maximum output (about 50 mW) that is currently available and obtaining the light emission amount (20 mW to 30 mW) in consideration of the life. When the following output is used, the light quantity will be further reduced. In addition, a high-power light-emitting element that serves as a light source is generally high in cost, and has a short life under high light emission, so that there is a limitation that the output of the light source cannot be increased unnecessarily.

As described above, in the multi-track read, the amount of light is reduced, and the S / N of the reproduced signal is deteriorated. Therefore, the reproduction becomes defective during reproduction, and the number of cases of retry is increased.

At this time, the cause of the defective reproduction is other than the card.
For example, in the case of a single electric noise or the like, the cause is removed at the time of retry, so that the reproduction can be performed by the retry. However, if the cause of the reproduction failure is a defect such as dust or scratches on the card, or a defect at the time of recording, the cause also exists at the time of retry, and therefore reproduction cannot be performed no matter how many times the retry is performed under the same conditions.

The present invention has been made in view of the above circumstances, and an object thereof is to provide an optical information recording / reproducing apparatus capable of improving the probability that a defective reproduction track can be reproduced by a retry.

[0012]

An optical information recording / reproducing apparatus according to claim 1 comprises a first light source for generating a recording light beam and a second light source for generating a reproducing light beam. An optical information recording / reproducing apparatus for reproducing information on a recording medium while recording information on the recording medium. When reproduction is poor, information is not recorded on the recording medium again. The reproduction is performed again by using the recording light beam having an amount of light not to be recorded.

An optical information recording / reproducing apparatus according to a second aspect of the invention includes a light source for generating a reproducing light beam for irradiating a plurality of tracks on a recording medium, and a plurality of reproducing the information of the plurality of tracks. An optical information recording / reproducing apparatus including a light-receiving element, wherein, when reproduction is defective, when reproducing again, the light-receiving element corresponding to the defective reproduction track among the plurality of light-receiving elements is Reproduction is performed again using the outputs of different light receiving elements.

[0014]

[Operation] According to the structure of claim 1, when the reproduction becomes defective and the reproduction is performed again, the reproduction is performed by the recording light beam having a light amount such that information is not recorded on the recording medium,
It improves the probability of being renewable.

According to the second aspect of the present invention, the reproduction failure occurs, and when the reproduction is performed again, the reproduction light beam is moved relatively to the recording medium, so that the reproduction failure among the plurality of reproduction light receiving elements. By using a reproducing light receiving element different from the reproducing light receiving element corresponding to the track,
It improves the probability of being renewable.

[0016]

Embodiments of the present invention will be described with reference to the drawings. 1 to 6 relate to a first embodiment of the present invention, FIG. 1 is a block diagram of an information recording / reproducing apparatus including a main part of the present embodiment, FIG. 2 is a general configuration diagram of an optical card, and FIG. FIG. 4 is a configuration diagram of an optical head incorporated in the information recording / reproducing apparatus according to the present embodiment, FIG. 4 is an explanatory diagram showing an image formation state on an optical card, and FIG. 5 is an explanatory diagram showing an optical image projected on a photodetector. 6 is an explanatory view showing the movement of the beam on the optical card.

The apparatus of this embodiment is an example of a multi-track readable apparatus capable of reading information recorded on a plurality of tracks on a recording medium.

In this kind of multi-track readable optical information recording / reproducing apparatus, a light source for generating a recording light beam and a light source for generating a reproducing light beam are independently provided.

FIG. 3 shows an optical system of an optical head incorporated in an optical information recording / reproducing apparatus capable of multi-track reading. The recording light beam generated by the semiconductor laser 14, which is the recording light source, becomes a substantially elliptical parallel beam by the collimator lens 15. In the shaping prism 16, the parallel beam is reduced only in the major axis direction of the ellipse,
Shaped into a nearly circular shape. Further, the diameter of the parallel beam is narrowed by the circular diaphragm 17 so that the spot size of the recording light beam becomes a predetermined value. The circular beam for recording which has thus become circular enters the polarization beam splitter 18. Since the circular beam is composed of almost S-polarized component due to the property of the semiconductor laser, most of the beam is reflected by the reflecting surface of the polarization beam splitter 18 and is incident on the optical axis of the objective lens 19. This incident light is condensed on the optical card 11 by the objective lens 19 to form a circular light spot 33 as shown in FIG. The energy density is locally increased by this light spot, and the recording layer of the optical card 11 is thermally added and reversely changed to form a recording pit.

The optical card 11 includes a track guide 27.
When a pulse modulated by the information to be recorded is given to the semiconductor laser to emit light in a pulsed manner, pits 31 are successively generated on the optical card 11, and in FIG. Information is recorded on the recording track 29 as an example of pits.

On the other hand, the light beam for reproduction uses, for example, a light emitting diode 20 such as an end face light emitting diode having a slit-shaped light emitting surface as a light source, becomes substantially parallel light by a collimating lens 21, and then P at the polarizing beam splitter 18. Only the polarized component is transmitted. This transmitted light passes through the objective lens 19
Incident on a position decentered from the optical axis with respect to the optical card 1
An image of the light emitting surface of the light emitting diode 20 is formed on the surface 1. The image formed by the objective lens 19 is the optical image 3 shown in FIG.
It is 2.

FIG. 4 shows a light image 32 of a light emitting diode formed on an optical card and a light spot 3 formed by a semiconductor laser.
3 is shown. The relative distance between the light image 32 and the light spot 33 is determined by the objective lens 1 when the optical head is assembled and adjusted.
It is obtained by giving a relative angular difference between the optical axis of the recording light beam before entering 9 and the optical axis of the reproducing light beam.

On the other hand, the light image 32 of the light emitting diode formed on the optical card 11 is specularly reflected on the optical card 11 with the track guide 27 and the light quantity modulated depending on the presence or absence of pits, and the reflection. The light passes through the objective lens 19 in the opposite direction and is guided to the polarization beam splitter 18 in the state of substantially parallel light. Since the reflected light is specularly reflected, it holds almost P-polarized light, almost passes through the polarization beam splitter 18, is reflected by the reflection mirror 22, and is condensed by the condenser lens 2.
It is condensed by 3 and enters the half mirror 24. The incident light is further divided into two by the half mirror 24, and each of the divided lights magnifies the optical image 32 on the optical card 11 on the light receiving surfaces of the photodetector 26 and the focus photodetector 25. To project. As described above, the reproduction light beam is incident on the position decentered from the optical axis of the objective lens 19, and so-called off-axis type focus detection is performed. On the focusing photodetector 25, for example, a two-divided light receiving element is arranged so as to detect the movement of the image of the reproducing light beam spot due to the focus shift.

FIG. 5 shows the light image 4 projected on the photodetector 26.
1, a light spot 42 is shown. On the photodetector 26, reproducing light receiving elements 35, 36, 37, a recording light beam corresponding light receiving element 38, and a tracking light receiving element 39.
a and 39b are provided. Reproduction beam light image 32
The image 41 enlarged and projected is formed at an appropriate position on these light receiving elements. Further, the light spot 42 forms an image at an appropriate position on the light receiving element 38.

Tracking detection is performed by taking the difference between the outputs of the track light receiving elements 39a and 39b divided into two. That is, the change in the position of the image of the track guide due to the track deviation is detected as the change in the amount of received light, and the tracking error signal is generated. Also, during playback,
The presence or absence of pits on the three tracks is detected by the light-receiving elements for reproduction 35, 36, 37 based on the change in the amount of light, and a reproduction signal is output.

FIG. 1 shows the configuration including the essential parts of the first embodiment. The outputs of the reproducing light receiving elements 35, 36, 37 and the recording light beam corresponding light receiving element 38 are respectively I / V.
The signals are input to the conversion circuits 1, 2, 3 and 4 and amplified and converted into current / voltage. The outputs of the I / V conversion circuits 1 and 3 are binarized by the binarization circuits 6 and 8 and the data demodulation circuit 9. The data is demodulated, processed by the data controller 10, and output as reproduction data to the host computer 34.

The outputs of the I / V conversion circuits 2 and 4 are input to the selector 5, and one output selected by the selector 5 is binarized by the binarization circuit 7. That is, the selector 5 selectively selects the I / V conversion circuit 2 or I / V according to the selection signal 44 output from the data controller 10.
The output of the V conversion circuit 4 is output to the binarization circuit 7. The data binarized by the binarization circuit 7 is demodulated by the data demodulation circuit 9.

In normal reproduction, the selection signal 44 output from the data controller 10 binarizes the output of the reproduction light receiving element, which is the output of the I / V conversion circuit 2, to reproduce the data, and As a result, the data of the tracks 28, 29 and 30 shown in FIG. 4 are reproduced.

In the reproduction processing, it is assumed that reproduction failure occurs in one of the three tracks attempted to be reproduced. The track in which the reproduction failure occurs is the track irradiated with the recording light beam (track 2 in FIG. 4).
In the case of 9), in this apparatus, the recording light beam is left in the same position in the retry operation, the output of the I / V conversion circuit 4 is selected by the selection signal 44, and the output is binarized, thereby performing the retry operation. Playback processing is performed.

Further, when the track in which the reproduction failure occurs is different from the track on which the recording light beam is irradiated (for example, the track 28 in FIG. 4), this apparatus determines that the recording light beam has failed. Move to the truck that occurred,
The output of the I / V conversion circuit 4 is selected by the selection signal 44,
By binarizing this output, a retry reproduction process is performed. FIG. 6 shows how the recording light beam 33 and the reproducing light beam 32 move on the card.

By performing the retry operation as described above, in the present embodiment, the track in which the reproduction failure occurs can be reproduced by using the recording light beam at the time of retry.

In this embodiment, since the recording light beam has a larger amount of light than the reproducing light beam, a signal having a good S / N can be obtained, and therefore the reproduction at the time of retry has better conditions than the reproduction at the time of occurrence of a defect. Since it can be done in the state, the probability of being reproducible by retry is high.

Of course, it is necessary that the light quantity of the recording light beam is smaller than the light quantity at the time of data recording so that no pit is recorded on the optical card 11. Incidentally, in order to reduce the light quantity of the recording light beam, a method of controlling the current supplied to the light source is generally used, but other than that, a filter for attenuating the light quantity is provided on the optical path of the recording beam. It may be done.

FIG. 7 is a block diagram of an information recording / reproducing apparatus including an essential part of the second embodiment of the present invention. As shown in FIG. 7, in the second embodiment, the selector 5 of the first embodiment is removed and a binarization circuit 43 is added. I /
The output of the V conversion circuit 2 is input to the binarization circuit 7, while the output of the I / V conversion circuit 4 is input to the binarization circuit 43. In addition, the drawings showing the image formation state on the optical head and the optical card and the optical image of the photodetector are the same as those of the first embodiment, and the operation thereof is also the same, and therefore the description thereof is omitted.

The outputs of the reproducing light receiving elements 35, 36, 37 and the recording light beam-corresponding light receiving element 38 are respectively I
The outputs of the I / V conversion circuits 1, 3 are binarized by the binarization circuits 6, 8 and amplified by the / V conversion circuits 1, 2, 3, 4 and the I / V conversion circuit 4 Output is 2
It is binarized by the binarization circuit 7. The respective outputs are demodulated by the data demodulation circuit 9, processed by the data controller 10, and output to the host computer 34 as reproduced data.

Therefore, the data on the track irradiated with the recording light beam is always the light receiving element 38 corresponding to the recording light beam.
Played by.

In the reproduction process, it is assumed that reproduction failure occurs in one of the three tracks. In the retry operation, the track with defective playback
When the track is irradiated with the recording light beam (track 29 in FIG. 4), the retry reproduction process is performed at the same position as the recording light beam.

However, since the defective reproduction under the above conditions is reproduced by the recording light beam, the probability of occurrence is not so large as that of other reproducing beams.

When the track in which the reproduction failure occurs is different from the track irradiated with the recording light beam (for example, track 28 in FIG. 4), as shown in FIG.
The recording light beam is moved to the track where the reproduction failure has occurred, and the retry reproduction processing is performed.

As described above, in this embodiment,
Since at least one of the plurality of tracks is reproduced by the recording light beam, the probability of defective reproduction can be reduced. Further, in the present embodiment, even if the reproduction failure occurs, the recording light beam is moved so that the reproduction at the time of retry can be performed under better conditions than the reproduction at the time of occurrence of the failure, so that the reproduction can be performed by the retry. The probability is high.

It should be noted that the output of the light receiving element 36 is input, as shown in FIG.
The structure shown within the wavy line is for verifying at the time of recording. That is, the recording light spot 3 shown in FIG.
It is used when reading and confirming whether or not the pits recorded in 3 are correctly formed.

Next, a third embodiment of the present invention will be described. The present embodiment has the same configuration as the conventional configuration shown in FIG. 8, but improves the probability of being reproducible by moving the retrieving light beam and retriing when retriing at the time of poor reproduction. Is possible.

This means that in the case of a multi-track readable reproduction light beam, the outputs of the light receiving elements corresponding to the respective tracks are not all under the same condition. For example, the output corresponding to the central part of the reproduction light beam However, the condition may be better than the output corresponding to the peripheral portion.

In the above example, when a reproduction failure occurs in a track reproduced in the peripheral portion of the reproduction light beam, for example, in the track 28 of FIG. 4, the reproduction failure track is reproduced as shown in FIG. The beam may be moved so as to be located at the center of the light beam and the retry operation may be performed.

In the present embodiment, when the number of multi-track reads increases, the difference in the reproduction condition depending on the position of the reproduction light beam becomes remarkable. This is because the reproduction light beam has to have a longer length in the vertical direction in FIG. 4 as the number of tracks to be read increases, resulting in a large light amount difference between the central portion and the peripheral portion.

Further, in this case, not only the recording / reproducing apparatus but also the reproduction only apparatus can be applied.

Although each of the above embodiments has been described by using the optical card as the recording medium, it is also effective for an apparatus using a disc.

[0048]

According to the optical information recording / reproducing apparatus of the present invention, it is possible to remarkably improve the probability that a defective reproduction track can be reproduced by reproduction again.

[Brief description of drawings]

FIG. 1 is a block diagram of an information recording / reproducing apparatus including a main part of the first embodiment of FIG.

FIG. 2 is an overall configuration diagram of an optical card.

FIG. 3 is a configuration diagram of an optical head incorporated in the information recording / reproducing apparatus according to the present embodiment.

FIG. 4 is an explanatory diagram showing an image formation state on an optical card.

FIG. 5 is an explanatory diagram showing an optical image projected on a photodetector.

FIG. 6 is an explanatory view showing the movement of a beam on an optical card.

FIG. 7 is a block diagram of an information recording / reproducing apparatus including a main part of the second embodiment.

FIG. 8 is a block diagram of an information recording / reproducing apparatus in a third example and a conventional example.

[Explanation of symbols]

 1, 2, 3, 4 ... I / V conversion circuit 5 ... Selector 6, 7, 8 ... Binarization circuit 9 ... Data demodulation circuit 10 ... Data controller 11 ... Optical card 14 ... Semiconductor laser (recording light source) 20 ... Light emitting diode (light source for reproduction) 28, 29, 30 ... Tracks 35, 36, 37, 38 ... Light receiving element

Claims (2)

[Claims] 1. A first light source for generating a recording light beam, and a second light source for generating a reproducing light beam,
In an optical information recording / reproducing apparatus for reproducing information on a recording medium while recording information on the recording medium, when reproduction becomes defective, when reproducing again, information is not written on the recording medium. An optical information recording / reproducing apparatus characterized in that reproduction is performed again by using the recording light beam having the light amount. 2. An optical information recording / reproducing apparatus comprising a light source for generating a reproducing light beam for irradiating a plurality of tracks on a recording medium, and a plurality of light receiving elements for reproducing information on the plurality of tracks. When a reproduction failure occurs, when reproducing again, the reproduction is performed again by using the output of a light receiving element different from the light receiving element corresponding to the defective reproduction track among the plurality of light receiving elements. An optical information recording / reproducing apparatus characterized in that