JPH0473217B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an optical recording information reading method and apparatus for reading data recorded on an optical recording medium, and particularly to a data recording area divided by strip-shaped reference lines. The present invention relates to an optical recording information reading method and apparatus for reading data from an optical recording medium in which a large number of data tracks are arranged in parallel perpendicularly to a reference line in the data recording area.

[Prior Art] In recent years, as an alternative to conventional magnetic recording media,
2. Description of the Related Art Optical recording media in which data is written by forming a pattern of changes in optical properties corresponding to digital information to be written, for example, a pattern of brightness and darkness, are being developed. There are two types of devices of this type: one in disk form and one in card or sheet form. In particular, optical memory cards are attracting attention as a large-capacity card-type storage device that can replace magnetic cards.

The structure of a card-type medium, which is a typical example of this optical recording medium, is shown in FIGS. 10 to 12. The optical recording medium shown in these figures has a card-type substrate 1 with
An optical recording medium 2 is deposited in layers, and the storage medium 2
, a parallel reference line 7 is provided, and a band-shaped area sandwiched between the reference lines 7 is defined as a data recording area 3.

A plurality of data recording areas 3 are usually arranged in parallel, and within each data recording area 3, a large number of tracks 4 forming data strings in the width direction are set at regular intervals. Each track 4 is provided with a memory cell 5, and one or more memory cells 5 record one bit of digital data.

In addition, this optical recording medium has a starting end reference line 6 along the track direction at one end of the entire data recording area 3, which serves as a reference for the starting end of the entire data recording area 3, and a T-shaped mark with respect to the reference line 6. provided in the shape to form,
A reference bus line 8 is provided as a reference for dividing and arranging the plurality of data recording areas 3 into two groups. However, there may be some that are not provided with the starting end reference line 6 and the reference bus line 8.

Data reading from an optical recording medium configured in this way is carried out using a CCD linear sensor, etc., which has a linear or planar field of view with a length slightly longer than the width of the data recording area and a width of at least one track. This is done by using a sensor to read out information recorded by the bright/dark pattern of the memory cells for each track. In this case, it is necessary to move the optical recording medium and the reading sensor relative to each other so that the track from which data is to be read faces the reading sensor in parallel. That is, it is necessary for the reading sensor to accurately follow the data string on the data recording area.

Conventionally, this type of control generally uses a sensor such as a limit switch to detect misalignment or inclination of the card, and uses the detection signal to control a servo system to correct the position of the card or reading sensor. It is.

[Problems to be Solved by the Invention] In the optical recording medium as described above, unlike magnetic cards, etc., the size of the memory cell for recording information,
They are arranged at high density with an arrangement interval of several microns to several tens of microns. Therefore, if the position of the reading sensor relative to the track from which data is to be read is slightly shifted or tilted, the data cannot be read accurately.

However, with conventional general control techniques, it is difficult to precisely detect slight positional deviations, inclinations, etc. of optical recording media. Of course, these detections are not completely impossible, but in order to realize them, it is necessary to specially prepare an ultra-high precision sensor, which is undesirable as it increases the manufacturing cost of the reading device.

The present invention was made to solve these problems, and uses a reading sensor as a sensor for detecting positional deviation, tilt, etc., without the need to specially prepare an ultra-high precision sensor. Therefore, it is an object of the present invention to provide a method and apparatus for reading optically recorded information, which makes it possible to accurately read data from a data string on a data recording area without increasing the manufacturing cost of the reading device.

[Means for Solving the Problems] The first to fourth inventions of the present application provide data recording areas divided by strip-shaped reference lines, and
The present invention relates to an optical recording information reading method and apparatus for reading data from an optical recording medium in which a large number of data tracks are arranged in parallel perpendicularly to a reference line in the data recording area, and each of them has the following structural requirements as a means to solve the problems. It is characterized by being prepared.

The first invention of the present application is an invention of an optically recorded information reading method, which includes: (a) a plurality of data tracks including a data track to be read and a reference line sandwiching these data are anticipated in the field of view of a reading sensor; , sequentially read data from the starting edge of the field of view, (b) extract a signal corresponding to the optical property of the reference line from the output signal of the reading sensor and sequentially detect the reference line, (c) detect the reference line in advance in the field of view; The present invention is characterized in that when a reference line in a set order is detected, data from a track in a data recording area partitioned by the reference line is read as regular data.

The second invention of the present application has in common the constituent features (a) and (b) of the first invention, and furthermore, (d) detects the position of the first reference line within the field of view and temporarily stores the position. (e) If there is no significant change, the position is compared with the memorized position of the previous reading, and (e) If there is no significant change, the position is compared with the position in the previous reading. When a line is detected, the data from the track in the data recording area divided by the reference line is considered normal data, and if there is a significant change, the reference line is determined to be the standard that is earlier or later than the preset ranking in the field of view. The present invention is characterized by the addition of two requirements: when a line is detected, data from a track in a data recording area defined by the reference line is read as regular data.

The third invention of the present application is an invention of an optical recorded information reading device, which includes: (a) a plurality of data tracks including a data track to be read and a reference line sandwiching these tracks in the field of view of a reading sensor; , reading means for sequentially reading data from the starting edge of the field of view; (b) extracting a signal corresponding to the optical property of the reference line from the output signal of the reading means, sequentially detecting the reference line, and generating a reference line detection signal; (c) counting the reference line detection signals and detecting a reference line in a preset order in the field of view from the reference line detection signals; A reading position indicating means for indicating the position of data from a track in a data recording area partitioned by the reference line.

The fourth invention of the present application shares the constituent features (a) and (b) of the third invention, and further includes: (d) a gate circuit for controlling the transmission of the output signal of the reading means; and (e) the field of view. Detects the position of the first reference line within the area, temporarily stores the position, and compares the position with the memorized position of the previous reading to monitor for significant fluctuations. (f) counting the reference line detection signals; and (f) counting the reference line detection signals; , if there is no change command, output a gate signal that opens the gate of the gate circuit when a reference line in a preset order is detected in the field of view from the reference line detection signal; If there is a command, reading position indicating means outputs a gate signal to open the gate of the gate circuit when a reference line located before or after a preset order in the field of view is detected. It is characterized by being

As a representative example to facilitate understanding of the configurations of each of the above inventions, a claim correspondence diagram corresponding to the constituent features of the fourth invention is shown in FIG.

[Operation] In the configurations of the first and third inventions, the reading sensor foresees a plurality of data tracks including the data track to be read and a reference line sandwiching these tracks in the field of view that can be captured at one time. ,
Reading is performed sequentially from the starting edge of the field of view.

Data can be read from the optical recording medium for one or several data recording areas within the field of view. When reading, not only the target data recording area but also the entire range from the beginning to the end of the field of view is scanned one track at a time. After scanning, the reading field of view is moved relative to the adjacent track.

In the first and third inventions of the present application, by detecting the reference line that partitions the target data recording area,
Only the data in the target data recording area is extracted from all the data read by the scan. That is, when a reference line in a preset order is detected in the field of view, data from a track in a data recording area defined by the reference line is read as regular data.

Therefore, as long as the data track to be read is captured within the field of view, data can be read from the target data track even if the field of view F shifts in the vertical direction.

The above-mentioned effect is similarly exhibited in the second and fourth inventions of the present application. However, the second and fourth inventions of the present application further have the following effects.

That is, as shown by the broken line in FIG. 2, while the field of view of the reading sensor and the data track are tilted and facing each other, the field of view F is shifted in the vertical direction by moving the reading sensor relatively along the longitudinal direction of the data recording area. This makes it possible to read data from the target data track even if the data track is

This shift in the field of view is detected from a change in the position of the reference line that first appears within the field of view. A variation is detected by determining whether or not there is a significant difference in the position of a reference line of a particular rank (for example, the first position) appearing within the field of view in two successive scans. In the second and fourth inventions of the present application, when the deviation in the track direction of the field of view is small, that is, when there is no significant change in the position of the reference line, the reference line in the preset order in the field of view is When detected, the data from the track in the data recording area divided by the reference line is regarded as normal data, while if there is a significant change, the reference line that is earlier or later than the preset rank in the field of view is determined as normal data. When detected, the data from the track in the data recording area defined by the reference line is read as regular data.

Therefore, according to the second and fourth inventions of the present application, even if the field of view of the reading sensor shifts in the track direction as the field of view moves in the direction of the data recording area, the shift can be detected using the reading sensor itself as a detection sensor. Moreover,
Data can be read accurately without mechanical position correction.

In the case shown in FIG. 2, the field of view F is approximately as wide as four data recording areas or more.

[Example] An example of the present invention will be described with reference to the drawings.

<Configuration of First Embodiment> FIG. 3 shows the configuration of a first embodiment of the optical recording information reading device. Note that the optical recording information reading device shown in the figure is an embodiment of the fourth invention of the present application, and
This is also an example of an apparatus for carrying out the optically recorded information reading method of the second invention of the present application.

The optical recording information reading device shown in the figure reads data from an optical recording medium in which a data recording area is defined by a strip-shaped reference line, and a large number of data tracks are arranged in parallel perpendicularly to the reference line in the data recording area. The apparatus includes a reading means 10, a gate circuit 20, a reference line detection means 50, a reading position change commanding means 60, a reading position instructing means 70, and a synchronization signal generation circuit 80, and The decoder 30 decodes the decoded signal, and the buffer 40 holds the decoded signal.

The reading means 10 includes a reading sensor 11 that sequentially reads data from the starting end of the field of view, taking into consideration a plurality of data tracks including the data track to be read and a reference line sandwiching these tracks in the field of view, and outputting the data as a video signal. and a binarization circuit 12 that binarizes the video signal output from the sensor 11 and outputs it as a binarized signal Bs.

The reading sensor 11 is composed of, for example, a CCD linear sensor, and a photodetector for detection is arranged in a range longer than about four data recording areas of the optical recording medium. This photodetector has approximately four times as many elements as the number of cells, for example, 2048 elements in this embodiment, arranged at intervals corresponding to each storage cell of one track.

Reading by the reading sensor 11 is performed by serially outputting charges accumulated in proportion to the amount of light received by each photodetector in accordance with a synchronizing signal φR, which will be described later. Its output becomes a video signal Vd for each track.

The binarization circuit 12 is composed of, for example, a differential amplifier, and compares the video signal Vd with a reference value to binarize it into a binarized signal Bs.

The gate circuit 20 is composed of, for example, an AND gate circuit, and controls the output signal of the reading means 10.

The reference line detection means 50 includes a signal level discrimination circuit 51 that extracts a signal of a constant output level corresponding to the reference line from the binary signal Bs, and a duration time that measures the duration of the signal extracted by the circuit 51. The measurement circuit 52 monitors whether the duration exceeds a certain time width and generates a reference line detection signal Ls when the duration exceeds a certain time width.
and a determination circuit 53 that outputs.
An example of the configuration of each part of this reference line detection means 50 is shown in FIG.

As shown in FIG. 4, the signal level discrimination circuit 51
For example, consists of an AND gate circuit 51a,
The synchronizing signal φR and an inverted version of the binary signal Bs are input. In addition, the duration measurement circuit 52
consists of a counter 52a and counts the synchronizing signal φR. This counter 52a is reset by a high level signal from the AND gate circuit 51a. Further, the determination circuit 53 includes a comparator 53
a, the count value of the counter 52a is compared with a preset reference value, and when the value exceeds the reference value, a reference line detection signal Ls is output.

The reading position change command means 60 includes a target reference line detection circuit 6 that detects the reference line that first enters the field of view in the reading based on the reference line detection signal Ls.
1, a readout position detection circuit 62 that detects the position within the field of view of the data being read by the reading sensor 11, and a readout position of the first reference line within the field of view detected by the target reference line detection circuit 61. A shift instruction that monitors whether there is a significant change in comparison with the readout position in the previous scan, and outputs a shift command signal Ss that instructs to change the readout position depending on the direction of the change if there is a significant change. The circuit 63 is configured to include a circuit 63. An example of the configuration of each part of the reading position change command means 60 is shown in FIG.

As shown in FIG. 5, the target reference line detection circuit 61
consists of, for example, a flip-flop circuit 61a and an AND gate circuit 61b. The flip-flop circuit 61a inputs a synchronizing signal φT giving the start timing of each scan to the set terminal S,
The reference line detection signal Ls is input to the reset terminal R, and its Q output is connected to the input of the AND gate circuit 61b. This AND gate circuit 61b
In addition to this, the reference line detection signal Ls is input.

The read position detection circuit 62 includes, for example, a counter 6
2a, reset by the synchronizing signal φT,
Count the synchronization signal φR.

The shift instruction circuit 63 includes a current value memory 63a and a previous value memory 63, which are comprised of, for example, registers.
b, and an arithmetic circuit 63c. The enable terminal E of the current value memory 63a and the arithmetic circuit 63c is connected to the AND gate circuit 61.
When the output of b is input and the output is high level,
Each is configured to import data.

Further, the current value memory 63a and the previous value memory 63b are configured such that the contents of the former are transferred to the latter in response to the synchronization signal φT. Further, the arithmetic circuit 63c has an arithmetic function and a judgment function, and the counter 62a and the previous value memory 63b are connected to its input. Arithmetic circuit 63c
calculates the difference between the two, and when the difference becomes extremely large, +1 or, depending on the sign of the difference,
-1 shift command signal Ss is output.

The reading position indicating means 70 receives the reference line detection signal.
From Ls, there is a reference line counting circuit 71 that counts reference lines to detect the reference lines that partition the data recording area to be read, and data to be read from the counted value from the reference line counting circuit 71 and the shift command signal Ss. Reading position determining circuit 7 that determines the position of the recording area
2. FIG. 6 shows an example of the configuration of each part of the reading position determination circuit 72.

The reference line counting circuit 71 includes, for example, a counter 71a.
and counts the reference line detection signal Ls.

Further, the reading position determining circuit 72 determines the position of the data recording area to be read by comparing, for example, the count value of the counter 71a with a target value. The up-down counter 72b has a preset function for setting, and an up-down counter 72b that has an up-down function for correcting the target value using the shift command signal Ss.

The synchronization signal generation circuit 80 is connected to the reading sensor 11.
On the other hand, there is a synchronization signal φR as a shift pulse for transferring the accumulated charge by the photodetector, and a synchronization signal φT for synchronizing the start of transfer for each track.
In addition, a synchronization signal for starting relative movement between the reading sensor and the optical recording medium is sent to a drive control device (not shown in this embodiment). In this embodiment, this synchronizing signal φR is output as a number of pulses corresponding to the number of elements of the reading sensor 11 between the two synchronizing signals φT and φT.

<Operation of the first embodiment> The operation of the first embodiment configured as described above will be explained with reference to the above figures and FIGS. 7 to 9B. In this example, it is assumed that the reference line of the optical recording medium is set so that the state of low reflectance continues. Therefore, as described below,
In the video signal read from the read sensor, consecutive portions of low output level correspond to the reference line.

To facilitate baseline discrimination, data should be FM
It is better to encode it. According to FM encoding, 1 bit of digital information “1” can be converted into 2 “0, 1” or “1, 0”.
On the other hand, "0" is expressed as two bits, "0,0" or "1,1". Therefore, by forming the reference line 7 so that the low level (or high level) continues for a certain period of time, it can be easily distinguished from the data portion.

First, in order to read data from an optical recording medium, a movement control device (not shown) causes the reading sensor 11 to face the track of the data recording area from which data is to be read. At this position, a synchronizing signal φT as shown in FIG. 7a is sent from the synchronizing signal generating circuit 80 to cause the reading sensor 11 to start the reading operation.
The reading sensor 11 serially transfers the charges accumulated in each photodetector by the synchronizing signal φR (see FIG. 7b) sent from the synchronizing signal generating circuit 80, and generates a video signal as shown in FIG. 7c. Output Vd. This video signal Vd is sent to a binarization circuit 12 and binarized.

After reading the data of one track in this way, the reading sensor 11 is sent to the next track by the movement control device and reads the data by the same operation as described above.

Next, effects specific to this embodiment will be explained.

The reading sensor 11 moves along the data recording area 3 on the optical recording medium C and reads data track by track. Field of view F captured by the reading sensor 11 at one time
range is a plurality of lines, but in this example, the range is the eighth line.
As shown in Figures A and 8B, it is approximately the width of four data recording areas. In this case, four reference lines 7
The standard is to keep the image within the field of view F.

The binarized signal Bs is sent to the gate circuit 20 and the reference line detection means 50. In the former case, the binary signal Bs is sent to the decoder 30 only when the gate is open.

On the other hand, in the reference line detection means 50, the counter 52
At a, the synchronizing signal φR is counted and the counted value is sent to the comparator 53a. Further, in the AND gate circuit 51a, the binarized signal Bs is sampled using the synchronization signal φR as a gate signal. When the synchronization signal φR and the binary signal Bs are both at high level, the output of the AND gate circuit 51a becomes high level. As a result, the counter 52a is reset.

The counter 52a counts the synchronizing signal φR, and counts again each time it is reset. Therefore, in this counter 52a, when the output of the binary signal Bs continues to be at a low level, the counted value is accumulated, and in other cases, it is reset in a short time and accumulated over a long time. It never happens.

The comparator 53a compares the count value of the counter 52a with a preset time width. Assuming that the count value reaches this time width setting value, the comparator 53a outputs the reference line detection signal Ls at that point.

The reference line detection signal Ls is sent to the reading position change command means 60 and the reading position instruction means 70.

The reading position change command means 60 includes a flip-flop circuit 61 which functions as a target reference line detection means.
a and the AND gate circuit 61b.

The flip-flop circuit 61a receives a synchronizing signal φT
It is reset by the reference line detection signal Ls, and its output terminal Q becomes a high level.It is also reset by the reference line detection signal Ls, and its output terminal Q becomes a low level. This synchronizing signal φT is output at the start of reading for each scan, so the flip-flop circuit 6
1a is set for each scan. On the other hand, the reset is performed by inputting the reference line detection signal Ls.

The AND gate circuit 61b operates when the output terminal Q becomes high level and the reference line detection signal
Only when Ls is input, its output becomes high level.

Therefore, the output of the target reference line detection circuit 61 becomes high level only when the reference line detection signal Ls of the reference line that first appears in the visual field is input.
This output serves as an enable signal for a current value memory 63a and an arithmetic circuit 63c, which will be described later. When this output becomes high level, the current value memory 63a and the arithmetic circuit 63c, which will be described later, become ready for data acquisition.

Further, in the reading position change command means 60, a counter 62a counts the synchronization signal φR.
This counting is reset and performed anew every time the synchronization signal φT is input. This count value is taken into the current value memory 64a and the arithmetic circuit 63c of the shift instruction circuit 63. This current value memory 64a
The count value is transferred to the previous value memory 63b in synchronization with the synchronization signal φT. The count value stored in the previous value memory 63b is taken into the arithmetic circuit 63c by the enable signal from the AND gate circuit 61b mentioned above.

The arithmetic circuit 63c compares the counted value of the counter 62a with the counted value stored in the previous value memory 63b, and if there is a significant change in the difference, +1 or -1 signal is output as shift command signal Ss. On the other hand, if there is no significant variation in the difference, these signals are not output.

The reading position indicating means 70 receives the reference line detection signal.
Ls is counted by the counter 71a, and this counted value is
A comparator 72a compares it with a target value to detect a data recording area to be read.

This target value is set in advance by the preset function of the up-down counter 72b. for example,
As shown in FIG. 8A F1, when reading the data recording area sandwiched between the second and third reference lines from the top of the field of view, this up-down counter 72b
Preset “2” to “2”. Also, Figure 8B F3
As shown in FIG. 3, when reading the data recording area sandwiched between the third and fourth reference lines from the top of the field of view, the up-down counter 72b is preset to "3".

Now, from the reading sensor 11, Vd1 in FIG. 9A
A video signal Vd as shown in is output. For this video signal Vd, the reference line detection means 50
In this case, a reference line detection signal Ls as shown in FIG. 9A Ls1 is output as the first signal of the field of view.

In this case, in the reading position instructing means 70, the counter 71a counts the reference line detection signal Ls, and the counted value is counted by the up-down counter 7.
When the target value "2" set in 2b is reached, the comparator 72a outputs a gate signal.

Upon receiving this gate signal, gate circuit 20 opens its gate. As a result, the binary signal Bs outputted from the reading means 10 is sent to the decoder 30, its contents are decoded, and the decoding result is stored in the buffer 40.

Thereafter, the reading sensor 11 is relatively moved in the longitudinal direction of the data recording area and reads data from adjacent data tracks. In this way, the data of adjacent tracks are sequentially read.

By the way, the reading sensor 11 and the data track should originally face each other in parallel, but it is difficult to achieve a completely parallel state. Therefore, in reality, the reading sensor 11 and the data track often lie on parallel planes and face each other with a slight angular deviation. Even if this angular deviation does not interfere with data reading of each track, as the reading sensor 11 is relatively moved in the longitudinal direction of the data recording area, the field of view of the reading sensor 11 is shifted in the data track direction. It will be displaced to.

When this displacement of the visual field becomes so large that the reference line seen within the visual field shifts by one line, the data recording area also shifts accordingly. Therefore, this displacement is monitored by the reading position changing means 60.

The reading position changing means 60 receives the reference line detection signal.
From Ls, the reference line of the monitoring target (in this embodiment, the reference line that first appears in the field of view) is detected by the target reference line detection circuit 61 consisting of a flip-flop circuit 61a and an AND gate circuit 62b. At the same time, the counter 62a is reset by the synchronizing signal φT, and the synchronizing signal φR is generated for each scan.
Count. When the target reference line detection circuit 61 detects the target reference line, this count value is calculated by the current value memory 63a of the shift instruction circuit 63 and the arithmetic circuit 63.
c. The count value stored in the current value memory is transferred to the previous value memory 63b in synchronization with the next synchronizing signal φT.

The arithmetic circuit 63c is activated for each scan by an enable signal output when the target reference line detection circuit 61 detects the target reference line, and calculates the count value from the previous scan from the previous value memory 63b and the counter. The count value from 62a at the time of the current scan is compared and calculated to find the difference. and,
When the difference is small, no signal is output,
When the difference is significantly large, a shift command signal corresponding to the sign of the difference is output.

For example, if the video signal was as shown in FIG. 9A Vd1 during the previous scan, and as shown in FIG. 9A Vd2 during the current scan, the detection position of the reference line detection signal Ls was at It became as shown in Figure Ls1, and when scanning this time, it became as shown in Figure 9A Ls2,
Varies significantly. This is because, as shown in FIG. 8A, the field of view F1 of the reading sensor 11 is shifted upward in the drawing as the field of view F2, and the reference line that did not appear at the beginning of the field of view F1 until the previous time is now located at the beginning of the field of view F2. By appearing. In this case, the arithmetic circuit 6
3c is a shift command signal to increase the target value by 1.
Output Ss.

On the other hand, for example, if the video signal was as shown in Figure 9B Vd3 during the previous scan and as shown in Figure 9B Vd4 during the current scan, the detection position of the reference line detection signal Ls may be different from that in the previous scan. As shown in Figure 9B Ls3,
During the current scan, there is a significant fluctuation as shown in Figure 9B Ls4. This is because, as shown in Figure 8B, the field of view F3 of the reading sensor 11 is shifted downward in the drawing like the field of view F4, and until the previous time, the field of view F3 was
This is because the reference line that had appeared at the starting edge disappeared from the starting edge of field of view F4. In this case, the arithmetic circuit 63c is
A shift command signal Ss is output in order to decrease the target value by -1.

In the reading position indicating means 70, the reference line detection signal Ls is counted by a counter 71a,
The counted value is sent to the comparator 72a. Also,
In the up-down counter 72b, the preset target value is set to + by the shift command signal Ss.
1 or -1. As a result, for example, if the preset target value is "2", the target value is changed to "3" when it deviates as shown in FIG. When counted, the comparator 72a outputs a gate signal Gs.
Further, for example, when the preset target value is "3", when the target value deviates as shown in FIG. 8B F4, the target value is changed to "2" and the counter 71a
When the comparator 72a counts two reference lines, the comparator 72a outputs the gate signal Gs.

In this way, when the gate signal Gs is output, the gate circuit 20 opens, and then the reading means 1
The binarized signal Bs output from the decoder 3
It is input to 0. Then, when the next reference line is detected, the count value of the reference line exceeds the target value, so the comparator 72a stops the gate signal. Therefore,
Only the data of the track in the target data recording area is selectively input to the decoder 30.

<Configuration of Second Embodiment> FIG. 13 shows the configuration of a second embodiment of the optical recording information reading device. The optical recording information reading device shown in the figure is an embodiment of the third invention of the present application, and is also an example of a device for carrying out the method of reading optical recording information of the first invention of the present application.

The optical recorded information reading device shown in the figure includes a reading means 10 having a reading sensor and a binarization circuit, a reference line detecting means 50 having a signal level discrimination circuit 51, a duration counting circuit 52, and a determination circuit 53.
Reference line counting circuit 71 and reading position determining circuit 72
The reading position instructing means 70 has a synchronizing signal generating circuit 80, a decoder 30 that decodes the read signal, and a buffer 40 that holds the decoded signal. This embodiment does not include the gate circuit 20 and the reading position change commanding means 60, and except that the reading position commanding means 70 and the decoder 30 have different configurations. This is the same as that of the first embodiment. Therefore, here, the explanation will focus on the differences.

In this embodiment, the decoder 3 does not have an independent gate circuit, but has a gate function at the input section.
0 is used.

Further, in this embodiment, the reading position change command means 6
0 is not provided, the circuit configuration of the reading position indicating means 70 is correspondingly simplified.

As shown in FIG. 14, this reading position indicating means 70 functions as a reference line counting circuit 71 that counts reference lines to detect reference lines that partition the data recording area to be read from the reference line detection signal Ls. A comparator 72a is provided as a reading position determining circuit 72 that compares the count value from the reference line counting circuit 71 with a preset target value to determine the position of the data recording area to be read.

In this embodiment, the counter 71a and the comparator 72a
This is the same as the first embodiment, but does not include an up-down counter for setting a target value. The target values are set based on the order in which the reference lines that define the data area to be read appear within the field of view, but unlike the first embodiment, they are fixed.
The configuration is such that it is set in the comparator 72a. However, the target value can also be varied, and in that case, for example, a register or the like may be connected as target value setting means.

<Operation of the second embodiment> The operation of the second embodiment configured as described above will be explained with reference to the above figures. The operation of this embodiment is basically the same as that of the first embodiment, but it does not have a reading position changing function. Therefore, since there is a difference in the operation of the reading position determining circuit 72, the explanation will focus on this.

The data read by the reading means 10 is binarized and sent to the decoder 30 as a binarized signal Bs.
and is sent to the reference line detection circuit 50. This binary signal Bs can be input to the decoder 30 only when an input permission signal is sent from the reading position determination circuit 72. On the other hand, the reference line detection circuit 50
Then, a reference line is detected from this binary signal Bs and output as a reference line detection signal Ls.

This reference line detection signal Ls is counted by a counter 71a, and the counted value is sent to a comparator 72a. Similar to the first embodiment, the comparator 72a compares this count value with the target value, and while the count value matches the target value, the input permission signal (the first
It may be the same as the gate signal Gs in the embodiment. ) is sent to the decoder 30.

In this way, target data is selectively input to the decoder 30.

<Modifications of Embodiments> The present invention is not limited to the above embodiments, and may have other configurations.

For example, in the first embodiment, the reading position instructing means is configured to change the target value in response to the deviation of the visual field, but it may also be configured to change the counted value of the reference line. Further, in the first embodiment, the gate circuit is provided independently, but it may be built into the decoder, reading position indicating means, etc.

On the other hand, in each of the above embodiments, the length of the field of view of the reading sensor is set to four data recording areas, but is not limited to this, and may be, for example, five or more. moreover,
In each of the embodiments described above, the monitoring target is the first reference line that appears in the visual field, but it can also be the second or subsequent reference line.

In each of the above embodiments, the description has been made mainly of detection in the case where all the reference lines have the same width, but the present invention is also applicable to cases where reference lines with different widths are included.

[Effects of the Invention] As explained above, the present invention provides a reading sensor that
By using it as a sensor to detect positional deviation, tilt, etc., it is possible to accurately read data on the data recording area without having to prepare a special ultra-high precision sensor and without increasing the manufacturing cost of the reading device. This has the effect of making reading possible.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of the optical recording information reading device of the present invention, FIG. 2 is an explanatory diagram showing the relationship between the field of view F of the reading sensor and the data recording area, and FIG. 3 is the optical recording information reading device of the present invention. 4 is a block diagram showing the configuration of the reference line detection means constituting the above embodiment. FIG. 5 is a block diagram showing the configuration of the reading position change command means constituting the above embodiment. FIG. 6 is a block diagram showing the configuration of the reading position indicating means constituting the above embodiment.
Figure 7 is a waveform diagram showing the waveform of the video signal from the reading sensor together with the synchronization signal, Figures 8A and 8B.
9A and 9B are waveform diagrams showing the relationship between the video signal from the reading sensor and the reference line detection signal, respectively. The figures are a plan view showing an example of an optical recording medium to which the present invention is applied;
FIG. 3 is a block diagram showing the structure of a first embodiment of the optical recording information reading apparatus of the present invention, and FIG. 14 is a block diagram showing the structure of the reading position indicating means constituting the above embodiment. DESCRIPTION OF SYMBOLS 1...Substrate, 2...Optical recording medium, 3...Data recording area, 4...Track, 5...Storage cell, 7...Reference line,
10... Reading means, 11... Reading sensor, 11... Binarization circuit, 20... Gate circuit, 30... Decoder, 4
0... Buffer, 50... Reference line detection means, 51... Signal level discrimination circuit, 52... Continuation time measuring circuit, 5
3... Judgment circuit, 60... Reading position change command means, 6
DESCRIPTION OF SYMBOLS 1...Target reference line detection circuit, 62...Reading position detection circuit, 63...Shift instruction circuit, 70...Reading position indicating means, 71...Reference line counting circuit, 72...Reading position determining circuit, 80...Synchronizing signal generation circuit.

Claims (1)

[Claims] 1. Optical recording information reading that reads data from an optical recording medium in which a data recording area is provided divided by a strip-shaped reference line, and a large number of data tracks are arranged in parallel in the data recording area perpendicular to the reference line. The method includes, in the field of view of the reading sensor, a plurality of data tracks including the data track to be read and a reference line that sandwich these tracks, and sequentially reading data from the starting edge of the field of view; extracting a signal corresponding to the optical property of the reference line from the output signal, sequentially detecting the reference line, detecting the position of the first reference line within the field of view, and temporarily storing the position; The position is compared with the memorized position of the previous reading, and the presence or absence of a significant displacement of the position of the reference line is monitored.Furthermore, if there is no significant displacement of the reference line,
When a reference line in a preset order is detected in the field of view, the data from the track of the data recording area divided by the reference line is regarded as regular data.On the other hand, if there is a significant displacement of the reference line, A method for reading optically recorded information, characterized in that when a reference line located before or after a preset rank in the field of view is detected, data from a track in a data recording area partitioned by the reference line is read as regular data. . 2. An optical recording information reading device for reading data from an optical recording medium having a data recording area divided by a strip-shaped reference line and a number of data tracks arranged in parallel perpendicular to the reference line in the data recording area, A reading means for sequentially reading data from the starting end of the field of view, with a plurality of data tracks including the data track to be read and a reference line sandwiching these tracks in the field of view of the sensor; and sending an output signal of the reading means. a gate circuit for controlling the reference line; a reference line detection means for extracting a signal corresponding to the optical property of the reference line from the output signal of the reading means, sequentially detecting the reference line, and outputting a reference line detection signal; Detecting the position of the first reference line within the field of view, temporarily storing the position, and
The position of the reference line is compared with the memorized position of the previous reading, and the presence or absence of a significant displacement in the position of the reference line is monitored. If there is a significant displacement, the data reading position is moved to a position earlier than the preset order in the field of view. or a reading position change command means for instructing a change to a later data recording area; and counting the reference line detection signal and, if there is no change command, presetting in the field of view from the reference line detection signal. When a reference line in the preset order is detected, a gate signal is output to open the gate of the gate circuit. On the other hand, if the above change command is issued, the reference line in the preset order is detected before or after the preset order in the field of view. When detected,
An optical recording information reading device comprising reading position indicating means for outputting a gate signal for opening the gate of the gate circuit.