JPH0677325B2 - Optical information processing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention will be described in the following order.

A Industrial Field B Outline of the Invention C Prior Art (FIG. 9) D Problems to be Solved by the Invention (FIGS. 10 to 12) E Means for Solving Problems (FIG. 1) ~ Fig. 5) F action (Figs. 1 to 5) G embodiment (G1) Basic configuration (Fig. 1) (G2) Rotation position adjusting device (Figs. 3 to 6) (G3) Second Embodiment of Rotational Position Adjustment Device (Fig. 7) (G4) Third Embodiment of Rotational Position Adjustment Device (Fig. 8) H Effect of Invention A Industrial Field of the Invention The present invention relates to optical information. The present invention relates to a processing device, and is particularly suitable for being applied to a case where optical information is recorded and / or reproduced by scanning a light beam on an optical recording medium in a direction transverse to its traveling direction.

B. SUMMARY OF THE INVENTION The present invention is designed to irradiate an optical recording medium with a scanning light beam through a rotatable cylindrical lens in optical information processing scanning in which a scanning light beam is scanned on the optical recording medium. As a result, the recording position accuracy of the scanning locus can be further improved.

C Prior Art Conventionally, as shown in FIG. 9, it is formed by an optical deflecting means 2 on an optical recording medium 1 such as a tape or a card which travels in the direction of an arrow a so as to cross the traveling direction. By condensing and scanning the scanning light beam LA2 through the condensing lens 3, the optical information light flux LA1 incident on the light deflector 2 is obtained.
An optical information processing apparatus that optically records the data on the scanning locus SCN of the optical recording medium 1 has been considered.

The optical information processing apparatus of this type can form the scanning loci SCN on the optical recording medium 1 at high density in the traveling direction a sequentially by making the light diameter of the scanning light beam LA2 sufficiently small. Therefore, it is considered that an optical information processing device capable of recording and / or reproducing information with high density can be realized.

D Problem to be Solved by the Invention However, when an optical information processing apparatus having such a configuration is to be constructed, the scanning locus SCN formed on the optical recording medium 1 by the optical deflecting means 2 is The light deflecting means 2 is arranged so as to be within a predetermined angle range with respect to the traveling direction a of the recording medium 1.
It is necessary to improve the mounting error.

That is, when the optical information is to be recorded on the optical recording medium 1 at a high density, the scanning locus formed by the optical deflecting means 2 is formed.
If the SCN position accuracy cannot be controlled with high accuracy, there is a risk that the optical information of this time will be overwritten on the recording track formed by the deflecting means 2 during the previous optical scanning. Is.

As a method to solve this problem, as shown in Fig. 10,
When the guide line GL is previously recorded on the optical recording medium 1 so as to maintain a predetermined interval in the scanning direction b, and the recording track TR is formed by the optical deflecting means 2, the optical deflecting means 2 is used. The scanning light beam LA2 is irradiated onto the guide line GL as the auxiliary light beam LA _SUB by this, and a tracking error signal for the optical head HDR is generated based on the reflected light, and thus moves integrally with the auxiliary light beam LA _SUB. A possible method is to form the recording track TR on the optical recording medium 1 by using a possible recording light beam LA _REC .

When reproducing a large number of recording tracks TR formed on the optical recording medium in this way, as shown in FIG. 11, a reproducing light beam LA _PB is irradiated from the optical head HDP onto the recording track TR, reproducing light beam LA by utilizing reflected light from the _PB light for reproduction beam LA _PB (sub connexion light head HDP) recording tracks T
Track to R.

Thus, by reproducing the optical information contained in the reflected light of the reproduction light beam LA _PB, the optical information recorded in the recording track TR can be reproduced.

In this way, the guideline GL or recording track TR previously formed on the optical recording medium 1 is used as the auxiliary light beam LA _SUB.
Alternatively, when the light beam scanning means of FIG. 9 is used when tracking is performed by the reproduction light beam LA _PB , the scanning locus SCN of the light beam LA _SUB or LA _PB is controlled by the tracking control as shown in FIG. In the case where the light deflecting means 2 is attached at a rotational position where there is an angular deviation from the target guideline GL or the recording track TR by an angle α, the light beam LA _SUB or LA _PB is the guideline GL. Or, because the recording track TR cannot be scanned, the light beam LA _SUB
Alternatively, the mounting angle of the optical deflecting means 2 must be adjusted in order to correct the incident position of the LA _{PB on} the optical recording medium 1. If this is not done, the tracking error signal sensitivity does not reach the maximum value when the scanning locus SCN is controlled to track in the traveling direction a.

However, in practice, the guidelines for the optical recording medium 1
It is actually extremely difficult to rotationally adjust the mounting position of the light deflecting means 2 in the direction of α based on the GL or the recording track TR.

For this reason, if the width W of the area for forming the recording track TR on the optical recording medium 1 is selected to be 1 [mm], the scanning locus SCN for the guide line GL or the recording track TR at both end positions thereof.
Error Δx in the running direction a is Δx = ± 0.1 [μm]
It is considered that some degree of accuracy is required.

At this time, the value of the mounting angle error α in the rotation direction of the light deflecting means 2 is As a result, a very small angle of about ± 20.6 ″ is required, and it is actually difficult to perform adjustment with such a high mounting position accuracy.

The present invention has been made in consideration of the above points, and an object thereof is to propose an optical information processing apparatus capable of easily realizing the correction of the scanning angle error of the scanning locus.

E Means for Solving the Problems In order to solve the above problems, in the present invention, the optical information beam LA1 is deflected by the optical deflecting means 2,
In an optical information processing apparatus configured to scan a scanning light beam LA2 on an optical recording medium 1, a cylindrical lens 11 is provided between the optical deflecting means 2 and the optical recording medium 1 and a focal line FOC of the cylindrical lens 11 is a scanning light beam. It is provided so as to extend in the direction along the scanning locus of LA2, and the cylindrical lens 11 can be rotated so as to correct the scanning angle of the scanning light beam LA2.

F action Cylindrical lens 11 incident scanning light beam LA2
Is focused by the cylindrical lens 11 in the direction of its focal line FOC, so that the positional accuracy of the scanning locus on the optical recording medium 1 is further improved even if the accuracy of the incident position from the optical deflecting means 2 is not so high. Can be improved.

In addition to this, by enabling the rotation control of the cylindrical lens 11, it is possible to further improve the tracking error detection sensitivity of the scanning locus with respect to the tracking scanning target.

G Embodiment One embodiment of the present invention will be described in detail below with reference to the drawings.

(G1) Basic Configuration As shown in FIG. 1 in which the same parts as those in FIG. 9 are denoted by the same reference numerals as in FIG. 9, the scanning light beam LA2 emitted from the light deflecting means 2 is converted into a cylindrical lens. Scanning locus SC by condensing on the optical recording medium 1 through 11 and the condenser lens 12.
Form NR.

The cylindrical lens 11 is arranged so that the center line CNT is aligned in a direction in which the focal line thereof is formed in a direction in which the focal line overlaps the guide line GL or the recording track TR formed on the optical recording medium 1 and thus is shown in FIG. As described above, when the light information beam LA1 that has entered the light deflecting means 2 is deflected by the light deflecting means 2 and draws a scanning locus SCNX on the incident surface 11A of the cylindrical lens 11, it enters on this scanning locus SCNX. The scanning light beam LA2 is refracted in the direction toward the focal line FOC, and the refracted light beam is condensed by the condensing lens 12, whereby the focal line of the cylindrical lens 11 is formed.
The irradiation light beam LA3 focused on the guide line GL or the recording track TR extending so as to overlap with the FOC actually forms the scanning locus SCNR on the optical recording medium 1.

With this configuration, the focal line of the cylindrical lens 11
If the angular position of the FOC is adjusted by rotating the cylindrical lens 11 so as to superimpose the FOC on the tracking scan target formed on the optical recording medium 1, that is, the guideline GL or the recording track TR, Formed on the optical recording medium 1 by refracting the scanning light beam LA2 at a position overlapping with the focal line FOC by the cylindrical lens 11 even if the positioning accuracy of the angular position in the rotation direction of the light deflecting means 2 is not so high. Practical scanning trajectory with sufficient accuracy for practical use on the specified tracking scanning target
SCNR can be formed.

(G2) Rotational Position Adjustment Device The cylindrical lens 11 described above with reference to FIGS. 1 and 2 is held by the rotation position adjustment device 15 shown in FIGS. 3 and 4.

The rotary position adjusting device 15 has a dovetail groove 17 formed in an arcuate shape on a fixed stage 16 and a rotator 18 that pivots slightly around a center of rotation O is slidably locked.

The rotation center O is set on the center line CNT which overlaps with the focal line FOC of the cylindrical lens 11, whereby the rotator 18
Is rotated about the rotation center O as indicated by an arrow d, the center line CNT (hence the focal line FOC) is the optical recording medium 1.
It can be rotated with respect to the traveling direction a.

In the case of this embodiment, the protrusion 21 protruding above the rotator 18 is fixed to the fixed stage 16, and the rotator 18 is rotated at the position of the rotator 18 facing the tip end thereof. A stator 23 formed by fixing the child 22 is fixed. The right end of the rotary driver 22 is coupled to the protrusion 21, and when the control voltage is supplied to the rotary driver 22, the rotary driver 22 made of a piezo element expands and contracts according to the value of the control voltage. By doing so, the rotator 18 can slightly rotate with respect to the fixed stage 16 in the direction of the arrow d.

According to the rotational position adjusting device 15 of FIGS. 3 and 4, the guideline GL in which the direction of the center line CNT (and hence the focal line FOC) of the cylindrical lens 11 is formed on the optical recording medium 1 is shown.
Alternatively, when the recording track TR is displaced in the rotational direction as described above with reference to FIG. 2, the position of the focal line FOC is controlled by controlling the expansion and contraction of the rotary driver 22 according to the displacement amount. , The guideline GL or the recording track TR can be aligned with high accuracy.

In this way, if the direction of the focal line FOC of the cylindrical lens 11 can be aligned with the guide line GL or the recording track TR formed on the optical recording medium 1, the optical deflecting means 2 rotates with respect to the cylindrical lens 11. Even if there is a slight error in the direction, the scanning light beam LA2 of the light deflecting means is moved to the center line CNT of the cylindrical lens 11 by the refracting action of the cylindrical lens 11 described above with reference to FIG.
(Consequently, the focal line FOC) can be aligned with high accuracy on the guideline GL or the recording track TR at a position where it is superposed.

In the case of this embodiment, the rotational position of the cylindrical lens 11 in the rotational direction is controlled by the rotational control device 24 configured as shown in FIGS. 5 and 6. That is, when the optical information on the recording track TR formed on the optical recording medium 1 is reproduced by the optical head HDP, the tracking pilot signal recording area RC1 is provided at both ends of the recording track TR (Fig. 5). And RC2 are formed, and in the tracking pilot signal recording areas RC1 and RC2 for tracking, the frequencies are sequentially ₁ , ₂ , ₃ , ₃ , ₁ , ₂ , ₃ ... 3
The frequency tracking pilot signals are sequentially recorded on the adjacent recording tracks TR.

Thus, when the light deflecting means 2 scans the normal scanning locus SCNX1, the 1-track deviation scanning locus SCNX2, or the 2-track deviation scanning locus SCNX3 by the irradiation light beam LA3 (Fig. 5), the optical head HDP is for tracking. According to the frequency of the pilot signal picked up from the pilot signal recording areas RC1 and RC2, the rotation control device 24 (6th
In the figure), a rotation error signal MVE is given to the rotation driver 22.

The rotation driver 22 sets the cylindrical lens 1 so that the rotation error signal MVE becomes 0 according to the rotation error signal MVE.
It is designed to drive 1 to rotate.

The rotation control device 24 applies the reproduction pilot signal PIL obtained from the optical head HDP to the bandpass filters BPF1, BPF2, BPF3.
To the output end of frequency ₁ ,
₂ and ₃ pilot detection signals S ₁ , S ₂ and S ₃ are transmitted.

The pilot detection signals S ₁ , S ₂ and S ₃ are respectively composed of a pair of sample and hold circuits SH11 and SH12, SH21 and SH22, SH.
Given to 31 and SH32.

The first sampling and holding circuits SH11, SH21, SH31 are supplied with the first sampling signal TIM1 from the timing generation circuit TM at the timing when the reproduction light beam LA _PB scans the first tracking pilot signal area RC1. Thus, when the optical head HDP detects the pilot signal PIL of the frequency ₁ , ₂ or ₃ , the pilot detection signals S ₁ , S ₂ and S ₃ sent from the bandpass filters BPF1, BPF2 and BPF3, respectively, are sent to the first Sample hold circuit SH1
Sample-hold to 1, SH21, SH31.

On the other hand, the timing generation circuit TM is
LA _PB is the second tracking signal recording area for tracking
When RC2 is scanned, the sampling signal TIM2 is sent to the second sample hold circuit SH12, SH22, SH32 at that timing.
And thus each of the bandpass filters BPF1,
Pilot detection signals S ₁ , S ₂ , sent from BPF2, BPF3
The S ₃ is sample-held in the second sample-hold circuits SH12, SH22, SH32.

Here, when the reproduction light beam LA _PB scans on the normal scanning locus SCNX1, as shown in FIG. 5, at the timing of the first and second sampling signals TIM1 and TIM2,
By reproducing the pilot signal PIL having the same frequency ₁ , ₂ , or _{3 from} each other, the sample-and-hold output S ₁₁ , or S ₂₁ , or S ₃₁ is output from the first sample-and-hold circuit SH11, SH21, or SH31. First in the comparison circuit COM
Given as a comparison input for.

On the other hand, when the pilot signal PIL of the pilot frequency ₁ or ₂ or ₃ is obtained at the timing when the reproduction light beam LA _PB scans the second tracking pilot signal recording area RC2, the bandpass filter B
Pilot detection signals S ₁ , S obtained from PF1, BPF2, BPF3
₂ and S ₃ are the second sample and hold circuits SH12 and SH2, respectively.
2, SH32 is sampled and held, and the sampled and held outputs S ₁₂ , S ₂₂ , and S ₃₂ are input to the comparison circuit COM.

The comparator circuit COM has sample and hold outputs S ₁₁ and S _{12 to} S _31.
Based on the combined output of S and S ₃₂ , the comparison output CP is given to the rotation error signal forming circuit CONT, and thus the rotation error signal corresponding to the comparison output CP is output from the rotation error signal forming circuit CONT.
The MVE is sent to the rotation driver 22.

That is, the comparator circuit COM outputs the sample-hold outputs S ₁₁ and S ₁₂ , or S ₂₁ and S ₂₂ , from the sample-hold circuits SH11 and SH12, or SH21 and SH22, or SH31 and SH32 at the same time.
Alternatively, when S ₃₁ and S ₃₂ are obtained, an output indicating that the scanning locus SCN is in agreement with the rotation angle of the tracking scanning target as the comparison output CP is output as the rotation error signal forming circuit CONT.
And thus outputs an output indicating the just tracking state as the rotation error signal MVE to the rotation driver 22.

In this state, the cylindrical lens 11 is driven so as to maintain the current rotation angle matching state.

On the other hand, the sample and hold outputs S ₁₁ , S ₂₁ , and S ₃₁ of the sample and hold circuits SH11, SH21, and SH31 and the sample and hold outputs S ₁₂ , S and S of the sample and hold circuits SH12, SH22, and SH32.
₂₂ and S ₃₂ do not match, the reproduction light beam LA _PB is 1
It can be determined that the track deviation scanning locus SCNX2 or the two track deviation scanning locus SCNX3 is being scanned,
A rotation error signal MVE corresponding to this is sent to the rotation driver 22 to control the rotation of the cylindrical lens 11 to a rotation position that matches the normal scanning locus SCNX1.

(G3) Second Embodiment of Rotational Position Adjustment Device FIG. 7 shows a second embodiment of the rotation position adjustment device 15, and parts corresponding to those in FIGS. 3 and 4 are designated by the same reference numerals. As shown, the rotator 26 fixed to the cylindrical lens 11 is supported so that it can rotate about a support shaft 25 provided on the fixed stage 16.

At both sides of the support shaft 25, the fixed stage 16
A spring 27 and a rotary driver 28 made of, for example, a piezo element are inserted between the rotary member 26 and the rotary member 26. When the rotary driver 28 expands and contracts in this way, the rotary member 26 resists the elastic force of the spring 27. Cylindrical lens by rotating the
The rotation angle position of 11 can be corrected.

Even with the configuration of FIG. 7, the scanning locus of the scanning light beam passing through the cylindrical lens 11 is changed to the guideline GL or the recording track TR on the optical recording medium 1 in the same manner as described above with reference to FIGS. 3 and 4. Can be aligned with.

(G4) Third Embodiment of Rotational Position Adjustment Device FIG. 8 shows a third embodiment of the rotation position adjustment device 15, and the same reference numerals are given to the corresponding portions in FIGS. 3 and 4. As shown by the attachment, a pair of connectors 31 and 32 are fixed to both ends of the cylindrical lens 11, and one connector 31 has springs 33 on both sides with the center line CNT of the cylindrical lens 11 interposed therebetween.
Also, a rotation driver 34 is provided between the fixed stage 16 and the connector 31.

At the same time, at the position on the center line CNT of the other connector 32,
A fulcrum projection 35 is provided so as to project outward and is pivotally supported by a fixing portion 36.

According to the structure shown in FIG. 8, by expanding and contracting the rotation driver 34, the cylindrical lens 11 can be rotated around the tip end position of the fulcrum projection 35 against the spring 33, and thus the third lens can be rotated. It is possible to obtain the same effects as those described above with reference to FIGS.

H Effect of the Invention As described above, according to the present invention, the scanning light beam emitted from the light deflecting means is focused in the focal line direction by using the cylindrical lens. The position accuracy can be further improved by controlling the tracking of the scanning light beam on the formed guide line or recording track.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of an optical information processing apparatus according to the present invention, FIG. 2 is a front view showing a cylindrical lens thereof, and FIGS. 3 and 4 are front views showing a rotational position adjusting device. A side view, FIG. 5 is a schematic diagram showing a recording pattern on an optical recording medium, FIG. 6 is a connection diagram showing a rotation control device, and FIGS. 7 and 8 are other embodiments of a rotation position adjusting device. An example is a front view, FIG. 9 is a perspective view showing a conventionally considered optical information processing apparatus, FIGS. 10 and 11 are schematic diagrams showing patterns on the optical recording medium, and FIG. 12 is scanning. FIG. 6 is a schematic diagram for explaining a trajectory error. 1 ... Optical recording medium, 2 ... Optical deflecting means, 11 ... Cylindrical lens, 12 ... Condensing lens, 15 ... Rotation position adjusting device, 22, 28, 34 ... Rotation driver, 24 ... … Rotation control device.

Claims (1)

[Claims] 1. An optical information processing apparatus configured to scan a scanning light beam on an optical recording medium by deflecting an optical information light beam by an optical deflecting means, wherein the optical deflecting means and the optical recording medium. A cylindrical lens may be provided in between so that the focal line of the cylindrical lens extends in the direction along the scanning locus of the scanning light beam, and the cylindrical lens can be rotated so as to correct the scanning angle of the scanning light beam. An optical information processing device characterized by the above.