JPS6316423A - Optical card reproducing device - Google Patents

Abstract

PURPOSE:To accurately read out data despite an error produced between the track direction and the scan direction of a detector, by setting a period when the information recorded on one plural track trains is reproduced by a reproducing means and reading an optical card where the information is recorded to an optical recording medium on plural track trains. CONSTITUTION:The reproduction signal of an optical card 100 is sampled by a sampling clock CK corresponding to a scan position. The reproduction signals obtained from the scan carried out between two no-signal scan periods are stored once in a RAM35 and then rewritten into reproduction signals of high levels for each scan. The data on a single track can be perfectly reproduced with use of the reproduction signals obtained from plural scans even though the perfect coincidence is obtained between the image forming direction of a line sensor 101, and the direction of a recording track T. As a result, the perfect reproduction signals equivalent to a single track are stored in a RAM35.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an optical card reproducing device for reading information recorded on an optical card.

[Summary of the invention]

The present invention provides an optical card reproducing device including a reproducing means having a detector for reproducing information by receiving reflected light from an optical recording medium of irradiated light from a light source, and a clock generator for supplying a sampling clock to the detector. and a period setting means for setting a period during which the reproducing means reproduces information recorded on the rear tracks of a plurality of trunk rows, the optical card having information recorded as a plurality of tracks on an optical recording medium. By reading the data, even if there is an error between the direction of the track and the scanning direction of the detector, the data can be read out accurately.

[Conventional technology]

Optical cards have been developed in which an optical recording medium film is sputtered or vapor-deposited on a card-shaped substrate, and various data are recorded as a track array on the optical recording medium film.

In other words, a laser beam modulated by a digital signal is scanned and irradiated onto this optical card through a galvanometer mirror, thereby forming a recording trunk on the optical recording medium film, and thereby data is written. Ru. The reflectance of the portion where the track is formed is changed depending on the recorded data.

Data recorded on an optical card is read by irradiating light onto a trunk formed on an optical recording medium film of the optical card and receiving the reflected light. Since the reflectance of the portion where the track is formed is changed according to the recorded data, data can be reproduced from the reflected light.

To read this data, a laser beam is irradiated while scanning along the track through a galvanometer mirror.
The reflected light may be received by a photodetector, or the track may be irradiated with light from a light emitting element, and this reflected light may be received by a line sensor consisting of an image sensor such as a CCD.
The light may be received for each line.

This optical card is a write-once recording medium, and data can be written on it, but data cannot be erased or re-recorded.

Optical cards are characterized by a much larger storage capacity than magnetic cards. Therefore, for example, information on bank deposit balances, medical chart information, etc. can be recorded on this optical card. In this way, various services can be realized by using optical cards.

To deal with optical card deterioration, the data recorded on the optical card is
An error correction code is added to improve reliability. This error correction code is applied in units of sectors, each consisting of a plurality of tracks, in order to perform powerful error correction.

(Problem to be solved by the invention) As mentioned above, reading data written on an optical card has conventionally been carried out by irradiating a laser beam along the trunk via a galvanometer mirror, and then detecting the reflected light. Alternatively, the track is irradiated with light from a light emitting element, and the reflected light is received using a line sensor consisting of an image sensor such as a CCD.

When reading is performed by irradiating with a laser beam while scanning, the recorded information of the l trunk cannot be completely obtained unless the laser beam scans along the track. Further, when using a line sensor, if the imaging angle of the line sensor and the angle of the track do not match, the recorded information of one track cannot be completely obtained. In order to match the scanning direction of the laser beam and the direction of the track, or the direction of imaging of the line sensor and the direction of the track, it is necessary to increase the accuracy of the optical card feeding mechanism. In order to improve the precision of the feed mechanism, it is necessary to improve the dimensional accuracy of the optical card and the precision of the feed mechanism of the reader. Therefore, improving the precision of the feed mechanism of the optical card will increase the cost. In addition, there are limits to the improvement of accuracy.

Conventionally, when reading an optical card by scanning a laser beam, a tracking servo is used to
The laser beam is controlled to scan over the recording trunk. Furthermore, when reading is performed using a line sensor, as shown in Japanese Patent Application No. 59-260398, for example, a timing signal formed on a recording track is detected, and a line sensor imaging angle and an angle of the recording track are detected. There has been proposed a system in which the error between the two lines is calculated and the cylindrical lens for forming an image of optical information on the line sensor is controlled to rotate so as to eliminate this error.

However, as described above, in order to perform tracking servo control and control of the imaging position of the line sensor, a circuit for performing feedback control and an actuator for the feedback control are required. Therefore, the structure becomes complicated and the cost increases.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an optical card reproducing apparatus that can completely reproduce recorded information even when the scanning direction of a beam or the direction of a line sensor is inclined with respect to a recording track.

Another object of the present invention is to provide an optical card reproducing device that does not require complicated feedback control, has a simple configuration, and can reduce costs.

[Means for solving problems]

This invention relates to an optical card in which information is recorded as a plurality of track rows on an optical recording medium, and a reproducing means having a detector that reproduces information by receiving reflected light from the optical recording medium of light irradiated from a light source. , a clock generating means for supplying a sampling clock to the detector; and a period setting means for setting a period during which the reproducing means reproduces information recorded on one track of a plurality of track strings. It is a card playback device.

[Effect]

Even if the scanning direction of the beam or the imaging direction of the line sensor and the direction of the recording track do not completely match,
By using the reproduction signal obtained through multiple scans, one track of data can be completely reproduced. The reproduction signal of the optical card is sampled by a clock corresponding to the scanning position. The reproduction signal obtained by scanning from the no-signal scanning period to the no-signal scanning period is once stored in a memory, and is rewritten to a higher level reproduction signal every time scanning is performed. This results in
A complete playback signal for one track is stored in the memory.

〔Example〕

Examples of the present invention will be described in the following order.

a, optical card used in one embodiment, b, reading device C0 in one embodiment, error detection between the direction of the scanning beam and the direction of the track d, one embodiment e, another embodiment r, modification a, one implementation Optical card used in the example FIG. 2 shows the optical card 1 as a whole. The optical card 1 includes, for example, an optical recording medium film (for example, a Te-C film) 3 sputtered or vapor-deposited on a resin substrate 2 . The optical card 1 is irradiated with a laser beam modulated by a digital signal while being scanned through a galvanometer mirror, thereby recording data. A recording trunk T is formed along the portion irradiated with the laser beam, and the reflectance of the portion where the track T is formed changes depending on the recorded data. Data is recorded on the optical card 1 by irradiating the track T with light and receiving the reflected light.

The optical card 1 used in one embodiment of the present invention includes a second
As shown in the figure, a track T is recorded perpendicularly to the longitudinal direction of the optical card 1. A plurality of tracks T constitute one sector S, and the sectors S are arranged in a matrix on the optical card 1. The size of one sector S is 512 bytes to 4 bytes. The recorded data is interleaved in units of sectors S,
An error correction code is attached.

b. Reading device in one embodiment FIG. 3 shows an outline of a reading device in one embodiment of the present invention. In Figure 3, 11 is optical card 1
This is a semiconductor or laser that serves as a light source for reading out the data recorded on the device. A laser beam emitted from a semiconductor laser 11 is collimated into a parallel beam by a collimating lens 12, and then is passed through a beam splitter 13 and an A wavelength plate 1.
4 and is reflected by the galvanometer mirror 15. The laser beam reflected by the galvanometer mirror 15 is focused by the objective lens 16 and irradiated onto the track T formed on the recording medium film 2 of the optical card 1. The galvanometer mirror 15 is swung as shown by the arrow B, whereby the laser beam irradiated onto the optical card 1 is scanned as shown by the arrow B.

The reflected light of the laser beam irradiated onto the optical card 1 returns to the objective lens 16 and is reflected by the galvanometer mirror 15.
The light passes through a two-wavelength plate 14. A 90° error occurs between the polarization axis of the laser beam emitted from the semiconductor laser 11 at the two-wavelength plate 14 and the polarization axis of the reflected light from the optical card 1 . The beam splitter 13 reflects the reflected light from the optical card 1 whose polarization axis has shifted at an angle of 90°. The reflected light from the optical card 1 reflected by the beam splinter 13 is focused by an objective lens 17, and is received by a photodetector 18 consisting of a photodiode. The photodetector 18 converts the optical signal into an electrical signal, and the output is taken out from the terminal 19.

As mentioned above, data is recorded in the track T of the optical card 1 as a track string, and the reflectance of the recording medium film 3 of the portion of the optical card 1 where the track T is formed is determined according to this recorded data. has been changed. Therefore, as described above, the laser beam from the semiconductor laser 11 is irradiated onto the track T of the optical card 1 while being scanned by the galvanometer mirror 15, and the reflected light is received by the photodetector 18. The recorded data is read.

20 is a guide roller, and the optical card 1 is fed stepwise by this guide roller 20.

When the laser beam is scanned once, the optical card 1 is moved along the guide roller 20 in the direction shown by arrow C, and the data of the next trunk is read.

21 is a semiconductor laser provided to detect positional information of a laser beam scanned onto the optical card l.

A laser beam emitted from a semiconductor laser 21 is collimated into a parallel beam by a collimating lens 22 and reflected by a galvanometer mirror 15. The laser beam reflected by the galvanometer mirror 15 is focused by the objective lens 23 and irradiated onto the photodetector 25 via the -dimensional grating 24 .

When the galvano mirror 15 is swung as shown by arrow A and the laser beam irradiated onto the optical card 1 is scanned,
Along with this, the laser beam emitted from the semiconductor laser 21, reflected by the galvanometer mirror 15, and received by the photodetector 25 is also scanned. This laser beam is
Since the light is irradiated onto the photodetector 25 through the -dimensional grating 24, the galvanometer mirror 1
A one-dimensional grid Rofuku corresponding to the movement of 5 is extracted.

Position information of the laser beam scanned onto the optical card 1 can be obtained from this -dimensional lattice clock.

C6 Error detection between scanning beam direction and trunk direction As described above, the laser beam emitted from the semiconductor laser 11 is scanned in parallel to the recording track T as shown by the arrow B by the galvanomirror 15. When one scan is completed, the optical card is moved stepwise along the guide roller 20 in the direction indicated by arrow C. Therefore, if the scanning direction of the laser beam and the direction of the recording track T completely match, as the optical card 1 is moved stepwise in the direction shown by the arrow C, the laser beam will move, for example, to the fourth Scan as shown.

That is, from the Nth scan to the (N+2)th scan, as shown in FIG. 4, each time the optical card 1 is moved in the direction shown by the arrow C, the scanning trajectory , and in the (N+2)th scan, the scanning locus X of the laser beam approximately coincides with the center of the track T. After the (N+2)th scan, the scanning trajectory X of the laser beam moves away from the center of the trunk T every time the optical card 1 is moved in the direction shown by the arrow C, and
After the (N+4)th scan, the scanning trajectory X approaches the center of the next track after the track T (.

Therefore, the reproduced signal of track T becomes as shown in FIG. In other words, the reproduction signal cannot be obtained in the Nth scan, and from the Nth scan to the (N+2)th scan, as the optical card 1 is moved in the direction shown by arrow C, the reproduction signal becomes thicker ( In the (N+2)th scan, when the laser beam scanning trajectory In the ('N+4)th scan, the reproduced signal of the track T is not obtained (from now on, the reproduced signal of the next track is gradually obtained).

If the direction of the scanning trajectory X of the laser beam and the direction of the recording track T completely match, the (N+1)th to The (N+3)th reproduction signal reproduces the entire information section of one track T.

However, if the scanning direction of the laser beam is different from the direction of the track T, the laser beam scans as shown in FIG. 6, for example. That is, in the Nth scan, in the first part of the scan, the scan trajectory
0 exists, but the scanning locus X0 is no longer on the track T in the latter half of the scan. Each time the scan is repeated, the scanning trajectory
The first part of the scanning trajectory X0 and the first part of the track T move away from each other, and the second half of the scanning trajectory X0 and the second half of the trunk T become close to each other. In the (N+3)th scan, the scanning trajectory X0 is present on the trunk T in the latter half of the scanning, but the scanning trajectory X0 is no longer on the track T in the first half of the scanning. In the (N+4)th scan, the entire scanning locus X0 is no longer on the track T.

Therefore, the reproduced signal of track T becomes as shown in FIG. That is, in the Nth scan, a large reproduced signal is obtained in the first half (2+-21) of the track T, after which the reproduced signal gradually becomes smaller, and eventually no reproduced signal is obtained. From the Nth scan to the (N+3)th scan, the part where a large reproduction signal is obtained moves to the latter half of the track T with each scan, and in the (N+1)th scan, the part (22 to zi) of the track T A large reproduction signal is obtained, and in the (N+2)th scan, the (ffi
A large reproduced signal is obtained at the part (z~J4), and (N+
3) In the second scan, a large reproduced signal is obtained in the Cp4 to Cp15) portion of the track T. In the (N+4)th scan, no reproduction signal can be obtained.

As is clear from FIG. 7, when the direction of the scanning trajectory X0 of the laser beam and the direction of the track T are different, the 1 The entire information section of the track is not being played.

However, as shown in FIG. 7, in the information section of one trunk, the section from (I18. to I) is completely reproduced in the Nth scan, and the section up to (lt-zs) is (N+1). completely scanned in the second scan,
The section from <is to 1m) is completely reproduced in the (N+2)th scan, and the section from
+3) Completely reproduced in the second scan. Therefore, by using the reproduced signal obtained between the Nth scan and the (N+3)th scan, it is possible to obtain all the reproduced signals for the information section of one track. In other words, (1
, ~h) is the Nth time.

Using the scanning reproduction signal, in the interval (it~13), (N
+1) Using the reproduced signal of the scan, (l, ~It4)
In the interval, the reproduction signal of the (N+2)th scan is used, and (
In the interval from j24 to l, ), if the reproduction signal of the (N+3)th scan is used, the information of one track can be completely reproduced, as in the case where the scanning direction is one line away from the direction of the recording track.

d. One Example As mentioned above, even if the scanning direction of the laser beam does not completely match the direction of the recording track, by using the reproduced signal obtained by multiple scans, it is possible to completely read the data of one track. Can be played.

FIG. 1 shows an embodiment of the present invention, in which the data of one trunk can be completely reproduced by using reproduction signals obtained by scanning a plurality of times in this manner.

In FIG. 1, terminal 1 of the photodetector 18 (see FIG. 3)
The reproduced signal of the optical card 1 taken out from the optical card 9 is supplied to the A/D converter 31. The A/D converter 31 includes
A one-dimensional grid lock CK is supplied which is taken out from a terminal 26 of a photodetector 25 (see FIG. 3). Photodetector 18
The reproduced signal output from the A/D converter 31 is sampled by this one-dimensional grid lock CK and digitized.

The output of the A/D converter 31 is supplied to a digital comparator 32 and also to a no-signal detection circuit 33. The no-signal detection circuit 33 detects whether or not no reproduced signal is obtained in one scan.

The detection output of the no-signal detection circuit 33 is supplied to the RAM controller 34. R by the RAM controller 34
The operation of AM35 is controlled.

Further, the one-dimensional grid lock CK output from the photodetector 25 is supplied to the address generation circuit 36. The address generation circuit 36 generates an address signal AD that is incremented by the one-dimensional grid lock CK. This address signal AD
is incremented during one scan and is set when one scan is completed. As described above, the -dimensional grating clock CK is generated corresponding to the scanning position of the laser beam, so this address signal AD corresponds to the scanning position of the laser beam.

When reading while scanning a laser beam, the swinging speed of the galvanometer mirror 15 varies with each scanning word, so if a constant period clock is used as the sampling clock of the reproduced signal and the step clock of the address generation circuit 26, , the position at which the reproduced signal is sampled for each scan varies, and the address signal AD for each scan may not completely correspond to the scanning position of the laser beam.

In this embodiment, a one-dimensional grid clock CK that changes in accordance with the movement of the galvanometer mirror 15 is used as the sampling clock of the reproduced signal and the step clock of the address generation circuit 26.

Therefore, the position at which the reproduction signal is sampled is always constant for each scan, and the address signal AD for each scan completely corresponds to the scanning position of the laser beam.

The RAM 35 is cleared when the no-signal detection circuit 35 detects no signal. Next, the reproduced signal data obtained in one scan is stored at the address designated by address AD.

In the next scan, the reproduced signal data from the A/D converter 31 is supplied to the digital comparator 32, and the address signal A corresponding to the position of the reproduced signal data of the A/D converter 31 at this time is supplied from the address generation circuit 36.
D is supplied to the RAM 35. Data at this address is read from the RAM 35, and this data is supplied to the digital comparator 32.

The digital comparator 32 compares the output data of the A/D converter 31 and the output data of the RAM 35, and outputs the larger data. This data is written to the corresponding address in RAM 35. Then, until one scan is completed,
The data with the larger corresponding address is written to the RAM 35 (.

Thereafter, the same process is repeated in the next scan, and the same operation as described above is repeated until the no-signal detection circuit 33 detects no signal.

By repeating such processing, the RAM 35
At each address, the reproduced signal data that was at the maximum level during multiple scans of the corresponding scan position is stored, respectively.

As described above, even if the scanning direction of the laser beam is different from the recording track direction, some portion of one track is reproduced in each of the plurality of scans. The reproduced part has a thick reproduced signal. Therefore, as mentioned above, the reproduced signal that was at the maximum level in multiple scans of the corresponding address is
By storing the data in the AM 35, all reproduced signal data obtained in one track is stored in the RAM 35.

When no signal is detected by the no signal detection circuit 35, the RAM3
The reproduced signal data for l tracks stored in 5 is read out. This reproduced signal data MD/A converter 3
7, and the output of the D/A converter 37 is output from the output terminal 38.

From the output terminal 38, a reproduction signal containing all the information of one track is taken out.

In this way, according to this embodiment, it is possible to extract an accurate playback signal containing all the emotional beats of one track from the output terminal 38 without performing torasoking control.

e. Another Embodiment If the inclination error in the scanning direction of the laser beam with respect to the direction of the recording track becomes so large that the laser beam scans across two tracks, the process shown in the above-mentioned embodiment cannot handle it. That is, as shown in FIG. 8, there is a recording track T and the following tracks Tk, l.
If the direction of the scanning trajectory XI is significantly different from the direction of In the (N+5)th scan, the first half of track Tk*1 is scanned. Therefore, the reproduced signal becomes as shown in FIG. 9. That is, in the Nth scan, the first half of the track Tk is reproduced, and in the (N+1)th scan, the first half to the center of the track Tk is reproduced, and the (N+2)th scan reproduces the first half of the track Tk.
) In the second scan, the center of the track air is regenerated,
In the (N+3)th scan, track T is reproduced from the center to the latter half. In the (N+4)th scan, the first half of tracks T and l are played back, as well as the second half of trunk T, and in the (N+5)th scan, from the first half to the center of track T1. or is played. In such a case, there will be no scanning period during one scan that results in a thermal signal.

Then, it becomes unclear which position of which scan is obtained from the reproduced signal data of one trunk.

FIG. 10 shows another embodiment of the invention. In this embodiment, the reproduced signal data obtained from the first half of the scan and the reproduced signal data obtained from the second half of the scan are divided, and the reproduced signal data obtained by multiple scans in each of the first half and the second half are divided. By using this method, reproduced signal data for the first half and the second half of one track are obtained, respectively, so that even if there is a large tilt error in the scanning direction of the laser beam with respect to the trunk direction, it can be handled.

In FIG. 10, an optical card reproduction signal taken out from a terminal 52 of a photodetector 51 is supplied to an A/D converter 53. In FIG. A one-dimensional grid lock CK taken out from a terminal 55 of a photodetector 54 is supplied to the A/D converter 53 . Optical card feeding mechanism and photodetector 51. The configuration of the photodetector 54 is similar to that of the previous embodiment. The reproduced signal output from the photodetector 51 is sampled by a one-dimensional grid lock CK in an A/D converter 53 and digitized.

The one-dimensional grid lock CK output from the photodetector 54 is supplied to an address generation circuit 56. The address generation circuit 56 generates two address signals ADI and AD2 that are incremented by the -dimensional lattice clock CK. The address signal ADI is advanced from the initial address A0 to the address Ak+p, as shown in FIG. address, large signal AD2 is address Ak-@
It is possible to proceed from the address to the address Al. As shown in FIG. 9, addresses (A, ~A7) correspond to one scanning section. Address A corresponds to approximately the center of one scanning section. Therefore, In the first half of one scan, the address signal ADI is output, and in the second half, the address signal AD2 is output.

At the center of one scan, addresses A1. -, to address Ak4. During this period, address signal ADI and address signal A
D2 is over-ramped and output.

In FIG. 1O, the output of the A/D converter 53 is supplied to no-signal detection circuits 57A and 57B, and also to digital comparators 58A and 58B. The no-signal detection circuit 57A detects whether there is no signal in the reproduced signal in the first half of one scan. The no-signal detection circuit 57B detects whether there is no signal in the reproduced signal in the latter half of one scan. Detection outputs of no-signal detection circuits 57A and 57B are supplied to RAM controllers 59A and 59B, respectively. RAM controllers 59A and 59B control the operations of RAMs 60A and 60B, respectively.

The RAMs 60A and 60B are cleared when no signal is detected by the no-signal detection circuits 57A and 57B, respectively.
Next, the reproduced signal data obtained in the first half of one scan is stored at a predetermined address in the RAM 60A by the address signal ADI, and the reproduced signal data obtained in the second half is stored in a predetermined address in the RAM 60B by the address signal AD2. It will be done.

In the first half of the next scan, the reproduced signal data from the A/D converter 53 is supplied to the digital comparator 58A, and the address generation circuit 56 outputs the reproduced signal data from the A/D converter 53 at this time.
An address corresponding to the position of the reproduced signal data of converter 53 is supplied to RAM 60A, and data at this address is read from RAM 60A and supplied to digital comparator 58A. Digital comparator 58A
The output data of the A/D converter 53 and the output data of the RAM 60A are compared, and the larger data is output from the digital comparator 58A. This data is R
Written to the corresponding address of AM60A.

In the second half of this scanning, the reproduced signal data from the A/D converter 53 is supplied to the digital comparator 58B, and the address generation circuit 56 outputs the reproduced signal data from the A/D converter 53 at this time.
An address corresponding to the position of the reproduced signal data of converter 53 is supplied to RAM 60B, and data at this address is read from RAM 60B and supplied to digital comparator 58B. Digital comparator 5
Output data of A/D converter 53 and RAM 60 in 8B
The output data of B is compared, and the larger data is output from the digital comparator 58B. This data is written to the corresponding address of RAM 60B.

Thereafter, similar operations are repeated in the first half and the second half of scanning until no signal is detected by the no-signal detection circuits 57A and 57B.

By repeating such processing, the RAM60
In each address of A, the reproduction signal data that was at the maximum level in the scanning of multiple circuits at the corresponding scanning position in the first half of scanning is stored, and in each address of RAM 60B, the reproduction signal data of the corresponding scanning in the second half of scanning is stored. The reproduced signal data having the maximum level in multiple scans of the position are stored respectively.

As a result, all reproduced signal data for the first half of the track is stored in the RAM 6()A, and all data for the second half of the track is stored in the RAM 60B.

When no signal is detected by the no signal detection circuits 57A and 57B, the data in RAM 60A is transferred to RAM 61A,
Data in RAM 60B is transferred to RAM 61B. R
AM61A and RAM61B are RAM controller 6
2A and RAM controller 62B.

Next, when no signal is detected, the data in RAM61A is
The data in RAM61B is transferred to AM63A, and the data in RAM61B is transferred to RAM63A.
63B. At the same time, data in RAM 60A is transferred to RAM 61A, and data in RAM 60B is transferred to RAM 61B. The RAM 63A is controlled by the RAM controller 64A, and the RAM 63B is controlled by the RAM controller 64A.
It is controlled by M controller 64B.

RAM 60A and RAM 60B store 1 data between the time when no signal is detected and the time when the next no signal is detected.
The reproduced signal data for the first half and the reproduced signal data for the latter half of the track are respectively stored.

Therefore, in this way, RAM60A and RAM60
The data stored in B is transferred to RAM61A, RAM63A and RAM61B, RAM63B, respectively, so that the reproduced signal data of the first half of two consecutive trunks is stored in RAM61A and RAM63B, and the data is transferred to RAM61A and RAM63B.
B. The reproduced signal data of the latter half of two consecutive tracks is stored in the RAM 63B.

The reproduction signal data of the first half of two consecutive tracks stored in RAM61A and RAM63A and RAM61B,
The reproduction signal data of the latter half of two consecutive tracks stored in the RAM 63B is transferred to the data comparator 65. This data comparator 65 is provided to detect reproduced signal data in the latter half of the track corresponding to reproduced signal data in the first half. This detection detects addresses that are overlapped between the first half and the second half (
This is done by using the reproduced signal recording data of Ak-, ~Ak,-).

In other words, as mentioned above, the address signal ADI and the address signal AD2 are the address (A knee, ~A1+@)
There is an overlap between Therefore, if the reproduced signal data of the first half and the reproduced signal data of the latter half are obtained from the same track, the data will be obtained between the overlapped addresses (A II-a to Ah-) of the two. There is a correlation between the reproduced signal data.

RAM61A, RAM63A with data comparator 65
The reproduction signal data of the addresses (A k-a to All+-) and the addresses of RAM61B and RAM63B (A k-
The reproduced signal data of *~A, , , ) is subjected to matrix calculation, and the correspondence relationship is determined. This determination output is supplied to the data comparison controller 66.

The data comparison controller 66 selects RAM 61A, RAM 63A, RAM 61B, and RAM according to this determination output.
It controls reading of M63B and also controls RAM 68 via RAM controller 67.

In other words, the address of RAM63A (Ak-, ~A1,)
The reproduced signal data and the address of RAM63B (A11-
, ~Ak, -), and if there is a correlation, the data stored in the RAM 63A is written to the RAM 68, and then the data stored in the RAM 63A is written to the RAM 68.
Write the data stored in 3B to RAM 68.

If there is no correlation here, the reproduced signal data at the addresses (A k-a to Ak4.) of RAM 63 A and the RAM 6
Determine whether there is a correlation with the reproduced signal data of the 1B address (A, -, ~Aゎ,), and if there is a correlation,
After writing the data stored in RAM63A to RAM68, the data stored in RAM63B is written to R.
Write to AM68.

If there is no correlation here, the address of RAM61A (A,
-, ~A110. ) and the reproduced signal data at the addresses (A k-s to Am-) of the RAM 63B. If there is a correlation, the RA
After writing the data of M61A to RAM68, the RAM
Write 63B of data to RAM 68.

If there is no correlation here, the address of RAM61A (A,
-, ~Ah, , ) and the reproduced signal data at the address (A, ~As5s) of RAM61B. If there is a correlation, the RAM
After writing 61A data to RAM68, RAM6
Write 1B data to RAM68.

By controlling in this manner, the reproduced signal data for one track is stored in the RAM 6B. R
When the reproduced signal data for one track is stored in the AM 68, the data in the RAM 68 is read out. The output of the RAM 68 is supplied to the D/A converter 69, and the output terminal 7
taken from 0. From the output terminal 70, a reproduction signal containing all the information of one track is taken out.

Note that if the error in the scanning direction of the laser beam with respect to the direction of the recording track is even larger, the scanning period may be further divided. How many times the scanning period is divided is determined by taking into consideration the accuracy of the feeding mechanism.

f. Modified Example The present invention can be similarly applied to a case where reading is performed using a line sensor consisting of an image sensor such as a CCD.

A reading device using a line sensor consisting of an image sensor such as a COD is configured as shown in FIG. 11th
In the figure, 101 is a line sensor consisting of an image sensor such as a CCD. The reflected light from the track T of the optical card 100 passes through the cylindrical lens 103 to the line sensor 1.
The image is focused on 01. The optical card 100 has a guide roller 1
04 in the direction of the arrow. Light is irradiated onto the tracks T of the optical card 100, and the reflected light is imaged on the line sensor 101 for each track T. A transfer lock is supplied to the line sensor 101, and the output of the line sensor 101 is transferred and taken out by this transfer lock.

In the case of a reading device using a line sensor, the transfer lock of the line sensor corresponds to the scanning position of the track. Therefore, in this case, the transfer lock of the line sensor can be used as the sampling clock of the reproduced signal and the sidewalk clock of the address.

That is, FIG. 12 shows a case where the embodiment shown in FIG. 10 is realized by a reading device using a line sensor. When using the line sensor 101, the first
As shown in FIG. 2, a transfer lock is supplied to the line sensor 101 from the clock generation circuit 110. This transfer lock is then supplied to the A/D converter 53 and also to the address generation circuit 56.

The present invention can be similarly applied to the case of reproducing an optical card in which tracks T are formed parallel to the longitudinal direction of the optical card as shown in FIG.

〔Effect of the invention〕

According to this invention, the reproduction signal of the optical card is sampled by the sample clock corresponding to the scanning position,
The reproduction signal obtained by scanning from the no-signal scanning period to the no-signal scanning period is once stored in a memory, and is rewritten to a high-level reproduction signal for each scan. The scanning direction of the beam or the imaging direction of the line sensor and the direction of the recording trunk may not match perfectly (but if you use the reproduction signal obtained from multiple scans, you can reproduce one track of data completely). As a result, a complete reproduction signal for one track is stored in the memory.Therefore, even if the scanning direction of the beam or the imaging direction of the inner sensor and the direction of the recording track do not completely match, Recorded information can be completely reproduced.

In this way, the accuracy of the feed mechanism can be improved and the recorded information on the track can be completely reproduced without performing complicated feedback control, so the configuration can be simplified and costs can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an embodiment of this invention, FIG. 2 is a plan view of an example of an optical card used in an embodiment of this invention, and FIG. 3 is an example of a reading device in an embodiment of this invention. Fig. 4 is a route map used to explain the case where no angular error occurs, Fig. 5 is a waveform diagram showing the reproduced signal when no angular error occurs, and Fig. 6 shows a route diagram when an angular error occurs. Figure 7 is a waveform diagram showing the reproduced signal when an angular error occurs, and Figure 8 is a route map used to explain when an angular error occurs. FIG. 9 is a waveform diagram showing a reproduced signal when a large angle error occurs, FIG. 10 is a block diagram of another embodiment of the present invention, FIG. 11 is a perspective view of another example of the reading device, and FIG.
The figure is a block diagram of still another embodiment of the invention, and FIG. 13 is a plan view of another example of the optical card. Explanation of main symbols in the drawings 1: Optical card, 3: Optical recording medium film, 11゜21
: Semiconductor laser, 24 one-dimensional lattice, 31.53:
A/D converter, 32.58A. 58B: Digital comparator, 35.60A,
60B: RAM in which playback signals are stored. Agent Patent Attorney Tadashi Sugiura Tomogu 1' Ma・Shiba h Suniri Device Diagram 3 N N+I N+2
N+3 N+4 AjiZ situation where there are no people. Figure 4 N N+I N+2 N+3
The pillars where N + 4T squares meet are also shown in Figure 6.
At the end of the image is large/) 4 Raw work 3 Figure 9 Lines, wrinkles and use R-customization, 1 Figure 11 Car F ゛ image 4 Figure 13 Hand ''' Corrector November 21, 1985 Hand-held Application No. 160588 2 Name of the invention Optical card reproducing device 3 Relationship with the person making the amendment Patent applicant address 6-chome, Kitashinyo, Tokyo Parts Co., Ltd. No. 7 No. 35 Name (2
18) Sony Corporation Representative Director Norio Ohga 4, Agent 170 Address: 1-48-10-6 Higashiikebukuro, Toshima-ku, Tokyo, Detailed description of the invention and drawing 7 in the specification subject to the amendment, Contents of the amendment ( 1) In the specification, on page 6, lines 12 to 13, the phrase "tracking servo" is corrected to "tracking servo." (2) Same, page 12, lines 2 to 7, "20 is a guide roller" to "reading is performed." are corrected as follows. ``20 is a table, and table 20 has an optical card l.
A mechanism (not shown) is provided for suppressing flapping in a direction perpendicular to the surface direction of the plate. This table 20 is a table that is movable in the X direction and the X direction by a driving source (not shown) such as a stenting motor.
The optical card 1 is fed step by step. Note that, instead of moving the optical card l in the X direction, it is also possible to move the optical system side. When the laser beam is scanned once, the optical card 1 is moved by the table 20 in the direction shown by the arrow C, and the data of the next track T is read. (3) Same, page 13, line 13, "guide roller 20" is corrected to "table 20." (4) Same as above, on page 20, line 16 and page 22, line 13, "no signal detection circuit 35" is corrected to "no signal detection circuit 33." (5) Same, page 28, line 18, "multiple circuits" is corrected to "multiple times." (6) In the drawings, Figure 3 will be corrected as shown in the attached drawing. 1. Low weight Fig. 3

Claims (1)

[Scope of Claims] An optical card in which information is recorded as a plurality of track rows on an optical recording medium, and a detector that reproduces the information by receiving reflected light from the optical recording medium of light irradiated from a light source. a clock generating means for supplying a sampling clock to the detector; and a period setting means for setting a period during which the reproducing means reproduces information recorded on one track of the plurality of track strings. An optical card reproducing device characterized by: