JPS61236028A - Optical recording medium - Google Patents

Abstract

PURPOSE:To obtain the titled optical recording medium capable of constituting a reader at low cost by providing a strip datum line having specified width in the optical recording region, using the region between the datum lines as a datum recording region and setting many datum tracks on the datum recording region in the direction vertical to the datum line. CONSTITUTION:An optical recording region 2 is provided on a plastic substrate 1 as large as a business card and plural datum lines 5 are furnished at regular intervals in the lengthwise direction of the optical recording region 2. The optical recording region 2 is composed of a substance on which binarily signaled information can be written as an occulting pattern by irradiating a beam such as a laser beam to locally change the optical properties such as reflectance. The datum line 5 is shaped in the form of a strip having specified width. The region between datum lines 5 is used as the datum recording region 3 and many datum tracks 4 are set on the datum recording region 3 in the direction vertical to the datum line 5. The datum track 4 consists of many recording cells 6 constituting the minimum unit of the occulting pattern and the data are recorded by the recording cell 4. Consequently, a reader can be constituted at low cost.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention provides a plurality of data tracks in an optical recording area, and optical tracks corresponding to digital information to be written on the track 2. The present invention relates to an optical recording medium in which data is written by forming a pattern of changing properties.

[Prior Art] In recent years, as an alternative to conventional magnetic recording media, optical recording in which data is written by forming a pattern of changes in optical properties corresponding to the digital information to be written, such as a light and dark pattern, has been developed. A medium is being developed. This optical recording medium is characterized by being capable of high-density, large-capacity recording. When high-density, large-capacity information becomes possible, information that was conventionally stored on magnetic tapes, magnetic disks, etc. can be stored on a recording medium as large as a conventional magnetic disk card.

By the way, in the development of recording media, it is necessary to popularize the recording medium, so it is necessary to construct a writing Φ reading device, particularly a reading device, at low cost.

Conventionally, practical optical recording medium reading devices have already been developed for disk-type media. For example, there is a format in which a light beam such as a laser beam follows a spiral track similar to the track on a record, and the reflected light from the track is detected by a reading sensor to read the written data. There is something.

However, this method cannot be applied to formats that are not suitable for writing and reading data by rotating the medium, such as card-shaped optical recording media in which data tracks are arranged linearly. has problems, and its practical application has been delayed.

That is, in a non-rotating recording medium such as a card-shaped optical recording medium, data is recorded by, for example, setting a large number of data tracks in a rectangular recording area, and recording data on the tracks.
This is done by forming an optical bright and dark pattern corresponding to the digital information to be written and writing the data. Therefore, when writing and reading data, it is necessary to control the movement of the writing/reading head in the X-Y directions. The foundation is ■
Writing and reading data using a spot light beam requires the writing/reading head to be constantly moved in the x-y directions, which poses a problem in that the moving mechanism and control mechanism for this purpose become complex.

On the other hand, it is conceivable to use a linear or planar reading element such as a CCD linear sensor. According to this type of linear sensor, data from one to several tracks can be read at one time over a certain range. Therefore, the mechanical movement of the sensor can be reduced, but this has the following problems.

[Problems to be Solved by the Invention] When reading data from a high-density, large-capacity recording medium using a CODCCD linear sensor, even a slight positional shift or angular displacement causes a reading error. Therefore, the reading device needs to detect the positional shift or angular shift, stop reading the data, and automatically correct the card position based on an instruction to reinstall the card or a detection signal.

However, in order to detect and correct this slight positional deviation using a sensor, a complex and highly accurate detection mechanism and control mechanism are required. Although this is technically possible, the device becomes expensive and becomes an impediment to the widespread use of reading devices.The present invention was made to solve these problems, and it Set your own positioning standards,
To provide an optical recording medium that can detect positional deviations and angular deviations by a reading head of a reading device, does not require a special complicated and highly accurate detection mechanism and control mechanism, and can configure a reading device at low cost. With the goal.

[Means for Solving the Problems] The present invention sets a large number of data racks in an optical recording area, and forms a pattern of changes in optical properties corresponding to digital information to be recorded on the tracks. The present invention is applied to optical recording media in which data is written in a manner similar to that shown in FIG.

First, a belt-shaped reference line having a constant width is provided in the optical recording area, and the area sandwiched between the reference lines a is used as a data recording area, and the data recording area is provided with a strip-shaped reference line having a constant width. Set up multiple data tracks vertically.

Second, the optical property change distribution in the width direction of the reference line is formed to be different from the optical property change pattern used for recording the data.

Next, the above configuration requirements will be explained in more detail.

The optical recording area is an area in an optical recording medium where actual recording is performed, and is made of a material that can record data by forming a pattern of changes in large optical properties using various means. For example, data may be recorded by physically or chemically changing the state of the 111 surface and changing the reflectance to form a bright and dark pattern.

The above reference line is not a line segment in the geometric sense,
This is a band-shaped area having a constant width. This reference line is not limited to being formed continuously and linearly in the longitudinal direction, but may be formed in various forms. For example, it may be formed in the shape of a broken line that accommodates a break corresponding to the interval between adjacent data tracks, or it may be formed not in a straight line. Further, the interval between the reference lines can be set as appropriate depending on the length of the data track.

The distribution of changes in optical properties in the width direction of this reference line needs to be different from the pattern of changes in optical properties used for recording the data. Therefore, when using, for example, optical brightness and darkness as a change in optical properties, when bright and dark states in the data appear at a constant rate regardless of their contents, the reference line It is sufficient to form the dark state so that it continues over a certain width.

[Function] In the above configuration, by providing a strip-shaped reference line in the optical recording area and defining the area between the reference lines as the data recording area, the data area can be easily distinguished from other areas. At the same time, the reference line can be used as a guideline for movement of a linear or planar sensor such as a CCD linear sensor.

In addition, by setting a large number of data tracks perpendicular to the reference line in the data recording area, data of one to several tracks can be recorded using a linear or planar sensor such as a CCD linear sensor. can be read at once.

At this time, by also reading the reference line with a linear or planar sensor such as a CCD linear sensor, it is possible to easily detect the positional or angular deviation between the sensor and the recording area.

Therefore, when reading data from one data recording area, there is no need to move the reading head in the track direction; instead, the reading head can be moved in parallel along the reference line while detecting the reference line on the data recording area. good. Therefore, the head moving mechanism can be easily configured and no special sensor for four positioning is required.

Furthermore, by forming the distribution of optical property changes in the width direction of the reference line to be different from the optical property change pattern used for recording the data, the data written on the track can be The reference line can be easily identified.

There are various methods of changing patterns of optical properties used for recording data. For example, FM encoding is an example. In the present invention, for example, the reference line is made clear at its widthwise end, and is set to "0" or "1".
" state continues, so that it can be distinguished from the binary encoded pattern of data by these FM encoding methods. Therefore, by checking the pattern of the read data in the reading device, the standard The position of the line becomes clear and positioning can be performed easily.

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

The following example is applied to a card-type optical recording medium. In particular, this is an example of an optical recording medium in which a difference in reflectance is adopted as a change in optical properties, and data is read based on the high or low reflectance. be.

<Configuration of Example> The optical recording medium of the example shown in FIG. It is constructed by providing a plurality of reference lines 5 at regular intervals in the direction.

The optical recording area 2 can be formed by locally changing optical properties such as reflectance (reflectance in this embodiment) by, for example, irradiating a light beam such as a laser beam or by using photographic technology. It is made of a material on which binary encoded information can be written as a light and dark pattern. Examples include a material that is locally melted by a light beam to change its reflectance, a photosensitive material, and the like.

This optical recording area 2 may be formed directly on the substrate 1, or may be formed in the form of a film and may be attached.

Each group? The S line 5 is formed into a band shape with a constant width, and in this embodiment, is formed continuously in the longitudinal direction.

The reference line 5 may be formed at the same time as the data is written, or may be formed in advance separately from the data writing. The formation can be performed by various methods depending on the material of the optical recording area 2, etc. For example, when forming the optical recording area 2, it can be formed together with data or alone using photographic technology, printing technology, etc. It is also possible to irradiate the optical recording area 2 with a laser beam to write in a band shape.

The area between each reference line 5 becomes the data recording area 3. In this data recording area 3, a large number of data tracks 4 are set in a direction perpendicular to the reference line 5. This data track 4 consists of a large number of recording cells 6, which constitute the minimum unit of a bright/dark pattern. Data is recorded by this recording cell 6.

Recording of data by this recording cell 6 is most simply as follows.
One recording cell represents one bit, but in this embodiment, data is binary encoded using the FM encoding method, so two consecutive recording cells represent one bit of data. That is, as shown on the right side of the waveform in FIG. 3, two consecutive recording cells are "0.
0” or “1.1” represents data “0”, while two consecutive recording cells are “0.1” or
In the case of "1, 0", it represents "1'" of data.

The width of each reference fi5 is sufficiently longer than the length of 1 bit of data, and as shown in FIGS. 2 and 3, the reflectance pattern in the width direction is clearly the same as the reflectance pattern of the data. It has a recognizable structure. That is, both sides 5a and 5c in the width direction are set to have a width corresponding to one bit of a recording cell used for recording data and have a high reflectance, while the middle part 5b in the width direction is set to have a high reflectance. The bit width is set to be several times as large as the number of recording cells required to represent one digital bit (in this embodiment, two bits), and the reflectance is set to be low.

<Operation of the Embodiment> The operation of the embodiment configured as described above will be explained with a focus on the operation of reading data written in the recording area.

Prior to the description, an overview of the reading device for reading data recorded on the optical recording medium of this embodiment will be explained with reference to FIG.

The optical recording medium reading device shown in FIG. 2 includes a reading sensor 10 that reads data by following the track 4 in the data recording area 3 shown in FIG. The main components include a binarization circuit 20, a buffer 30 for temporarily storing the binarized signal Bs, and a reference line detection means 40 for detecting the reference line 5 from the binarized signal Bs. Ru. In addition to the main parts mentioned above, the optical recording medium reading device also includes a movement control device, a synchronization signal generation circuit, a light source, an output data processing device, etc. (all not shown).
However, since these are not directly related to the operation of this embodiment, their explanation will be omitted.

The reading sensor 10 is composed of, for example, a CCD linear sensor, and has a photodetector for detection arranged in a range longer than the width of the data recording area 3 of the optical recording medium. In this photodetector, 1) the number of elements is twice as many as the number of cells, for example, 1024 elements, in this embodiment, are arranged at intervals corresponding to each recording cell 6 of the rack.

Reading by the reading sensor 10 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. Its output becomes a video signal Vd for each track.

The binarization circuit 20 is a comparator that compares the video signal Vd with a certain threshold, sets a portion of the waveform larger than the threshold to a high level, sets a portion smaller than the threshold to a low level, converts it into a binarized signal Bs, and outputs the signal. It is composed of:

The buffer 30 is configured with an input/output control gate and a register, and alternately opens and closes the control gates on the input side and the output side according to the input of the reference line detection signal Ls, which will be described later, and outputs the binary signal BS. , and outputs a binary signal Bs.

The reference line detection means 40 includes an AND gate circuit 41 that samples the high level portion of the binary signal Bs output from the binary circuit 2o in synchronization with the synchronizing signal φR.
The counter 4 is reset by the output of the AND gate circuit 41 and counts the synchronizing signal φR.
2, and a comparator 43 that compares the counted value output from the counter 42 with a preset time width and outputs a reference line detection signal Ls when the counted value is larger than the set time width. Ru.

This set time width value is set by converting the width of the reference line to be detected into the number of synchronizing signals φR, which corresponds to the time required for reading by the reading sensor 10. In this example,
This is set to 40 pulses of the synchronizing signal φR. This value is set almost permanently.

The operation of the embodiment in the reading device configured as described above will be explained.

First, in order to read data from an optical recording medium, a movement control device (not shown) causes the reading sensor 10 to face the track of the data recording area 3 from which data is to be read. At this position, the reading operation of the reading sensor 10 is started. The reading sensor 10 serially transfers the charges accumulated in each photodetector by a synchronization signal φR sent from a synchronization signal generation circuit (not shown), and as shown in FIG.
It is output as a video signal Vd as shown in a). This video signal Vd is sent to a binarization circuit 20 and binarized.

After reading the data of one track in this manner, the reading sensor 10 is sent to the next track by the movement control device and reads the data by the same operation as described above.

The reading sensor 10 reads the data recording area 3 on the optical recording medium 2.
, and reads data one band at a time. The range of the field of view F that can be captured by the reading sensor 10 at one time is approximately the width of two trees of the data recording area 3, as shown in FIG. In this case, it is standard that the two-tree reference line 5 is always within the field of view F.

The binarized signal Bg output from the binarization circuit 20 is
The signal is sent to the buffer 30 and the AND gate circuit 41.

In the buffer 30, when the gate is open, the binary signal Bs is stored according to the reference line detection signal Ls, which will be described later, and when the gate is closed,
Storage is prevented.

On the other hand, the AND gate circuit 41 receives the synchronization signal φR together with the binary signal Bs. Therefore, the AND gate circuit 41 outputs a pulse synchronized with the synchronizing signal φR when the binary signal BS is at the /S high level.

The counter 42 is reset by the output pulse from the AND gate circuit 41. In this counter 42,
The synchronizing signal φR is counted, and each time it is reset, it is counted again. Therefore, in this counter 42, when the output of the binary signal Bs continues to be at a low level, the counted value is accumulated. In other cases, it is reset immediately and is not cumulatively added.

The comparator 43 compares the count value of the counter 42 with a preset time width. Now, if the count value reaches this time width setting value, the comparator 43 outputs the reference line detection signal Ls at that point. As shown in FIG. 5(b), the reference line detection signal Ls falls at the time when the video signal Vd rises from a continuous low level region to a high level region.

This reference line detection signal Ls is sent to the buffer 30 described above. In the buffer 30, this first reference line detection signal Ls
opens the input gate and closes the output gate.

After this, as shown in FIG. 5(a), in the area where the No/Iro appears alternately at short time intervals, the counter 42 is constantly reset, so that the counted value does not reach the time width setting value. do not.

When the second low level continuation region is reached, the count value of the counter 42 reaches the time width setting value, and the reference line detection signal Ls is outputted, as described above.

This reference line detection signal Ls is sent to the buffer 30 described above. In the buffer 30, this second reference line detection signal L
s closes the input gate and opens the output gate.

This allows only data from the track to be read from the output of the reading sensor 10, which includes the two reference lines, the data of the tracks sandwiched between them, and part of the data of the tracks outside the two reference lines. can be taken out. Therefore, the field of view F of the reading sensor 10 is slightly up and down (in the track direction).
Even if the position shifts, there is no need to make minute and complicated position corrections.
It becomes possible to read data accurately.

Furthermore, it is also possible to detect positional deviation and angular displacement of the reading head based on the time width from the start of reading the video signal to the position of the reference line.

<Modification of the embodiment> In the above embodiment, the reflectance pattern in the width direction of the reference line is set to “1”.
00...001", but it is not limited to this, and other patterns can also be used. For example, 'O
It may be 11...110''.

Further, in the above embodiments, an example of a card-type optical recording medium is shown, but the present invention is not limited to this, and it may be in a sheet-like or tape-like form.

Further, in the above embodiments, data is recorded based on the difference in reflectance, but the invention is not limited to this, and changes in optical properties such as transmittance, polarization, etc. can also be used.

[Effects of the Invention] As explained above, the present invention provides a positioning standard on the recording medium itself, can detect positional deviation and angular deviation with the reading head of the reading device, and has a complex and highly accurate detection mechanism and control mechanism. This has the advantage that the reading device can be constructed at low cost without the need for special components.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing an embodiment of the optical recording medium of the present invention, FIG. 2 is an enlarged plan view of the main part thereof, and FIG. 3 is a waveform diagram showing the reference line and data reflectance pattern in the above embodiment.
FIG. 4 is a block diagram showing the configuration of an example of the reading device for reading data from the optical recording medium of the above embodiment, FIG. 5 is a waveform diagram showing the relationship between the video signal from the reading sensor and the reference line detection signal, and FIG. FIG. 6 is an explanatory diagram showing the relationship between the field of view of the reading sensor and the data recording area. l... Substrate 2... Optical recording area 3
...Data recording area 4...Track 5...Reference line 6...Recording cell 10...Reading sensor 20...Binarization circuit 303.6 buffer
4o... Reference line detection means 41... AND gate circuit 42... Counter 43... Comparator Applicant Computer Service Co., Ltd. Agent Patent attorney Iwao Mishina Figure 1 Figure 2

Claims (1)

[Claims] A type of optical system in which a large number of data tracks are set in an optical recording area, and data is written on the tracks by forming a pattern of changes in optical properties corresponding to digital information to be recorded. In the recording medium, a belt-shaped reference line having a constant width is provided in the optical recording area, and an area sandwiched between the reference lines is defined as a data recording area, and an area perpendicular to the reference line is provided in the data recording area. A large number of data tracks are set in the data track, and the distribution of optical property changes in the width direction of the reference line is formed to be different from the optical property change pattern used for recording the data. optical recording medium.