JPH01133221A - Method and device for information reproduction - Google Patents

Abstract

PURPOSE:To reproduce information without receiving the influence of the dust, the flaw of an area except a pattern part by deciding whether the information of an information track having the pattern part can be reproduced or not according to that the pattern part is detected or not. CONSTITUTION:An optical card 1 mounted on a belt 5 is reciprocally moved to the direction shown by an arrow A by a rotating mechanism 6. The information recorded on the optical card 1 is read and reproduced by an optical head 11 for every track. A light from a light source 7 irradiates the optical card 1 through a lens system 8 and the image of the track is formed on one dimensional sensor array 10 by an image forming optical system 9. The identifying area 22 of the information tracks 12a-12c of the optical card 1 consists of a pattern part 13a having a slash part 14 and a non pattern part 13b having no slash. When a signal pattern is detected by scanning the sensor array 10, it is identified that the reading position of the sensor array 10 is situated on the track.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an information reproducing method and an information reproducing apparatus used therefor, and in particular has an identification area on an information track for separating and identifying it from adjacent information trunks, An information reproducing method of an optical information recording carrier having a 9-tang part in which an identification area is formed with a predetermined pattern consisting of a low reflection part and a high reflection part or a low transmission part and a high transmission part, and information reproduction used therein Regarding equipment.

[Prior Art] Conventionally, information recording carriers used for recording information using a light beam and reproducing the recorded information using a light beam have various shapes such as a card shape, a disk shape, and a tape shape. The one made of oak is known.

Among them, optical information recording carriers formed in the form of cards (
2. Description of the Related Art Optical cards (hereinafter referred to as "optical cards") are expected to be in great demand as information recording carriers that are easy to manufacture, have good portability, and have good accessibility.

FIG. 3 is a schematic plan view showing an example of the configuration of an optical card.

FIG. 4 is a partially enlarged view of the recording former 7) of the optical card.

In FIG. 3, an information recording area 2 is provided on the optical card 1, and the information recording area 2 is formed by a plurality of bands 3 arranged in rows. A large number of information tracks 4 are arranged in these bands 3, and each track 4 has several tens to ten information tracks.
It has an information amount of about 0 bits.

Each track has a grid area 21 for creating a synchronized clock for information reproduction, an identification area 22 for separating and recognizing the trunk from other tracks, and information modulated by MF'M modulation etc. is recorded. It consists of an information area 23, an end bit area 24 indicating the end of information, and the like.

The information area 23 consists of a start bit 30 indicating '#I' of information and a recording section 31 in which information is recorded.

Note that arrow A indicates the moving direction of the optical card 1 during reproduction, and arrow C indicates the information reading scanning direction of the optical head during reproduction.

FIG. 5 shows a schematic diagram of a device used for recording and reproducing the optical card as described above.

In the figure, an optical card 1 is placed on a belt 5 and can be moved back and forth in the direction of arrow A by a rotation mechanism 6. Information recorded on the optical card 1 is read and reproduced track by track by the optical card 11. Light from a light source 7 such as an LED is focused by a lens system 8 and illuminates the optical card 1. The image of the track on the optical card 1 is formed by the imaging optical system 9.
An image is formed on the one-dimensional sensor array 10 by. Thus, an electrical signal corresponding to the information recorded in the trunk 4 is output from the sensor array 10.

The operation of reading the information track by the sensor array 10 will be described below.

FIG. 6 is a partially enlarged schematic diagram of the identification area of the optical card 1 shown in FIG. 4. However, the shaded area in the figure indicates a low reflectance area and represents information "1". Further, a blank area indicates a high reflectance area and represents information "0".

In the figure, 12-a, 12-b, and 12-c are three information tracks that are continuous in the direction of the arrow on the optical card 1, and 22 is an identification area.

If the minimum bit width in the optical card 1 is IT, the identification area 22 has diagonal line portions 17.20 on both sides, IT blank portions 18.19 from both sides toward the center, and 4T in the center. It is formed with a diagonal line portion 14 . However, the width of the central hatched portion 14 in the track arrangement direction (direction A) is 1/1/2 of the width of the information track (for example, 12-a).
2, and is located approximately at the center of the information track in the width direction. That is, the identification area 22 has the diagonal line part 14 in the direction A in the figure! Turn portion 13a and diagonal line portion 1
4 and a non-pattern portion 13b without a pattern.

Figure 7 (,) and Cb) are the identification area 1 in Figure 6.
3 is a binary signal obtained as a result of modulating the above-mentioned minimum bit width IT in correspondence with the minimum inversion interval of the signal. However, FIG. 7(,) shows the case where the reading position of the sensor array 10 is in the on-track state, that is, the thick line 1
FIG. 7(b) shows a binary signal corresponding to the position shown in FIG. 5 (on the pattern section 13a), and FIG. This is a binary signal when the signal is on the pattern section 13b), for example, when it straddles the information trunks 12-b and 12-C. As shown in the figure, when the reading position of the sensor array 10 is at the position indicated by the thick line 15 in FIG. 6, the detected signal has a maximum inversion interval of 4T (FIG. 7(a)).

Furthermore, when the reading position of the sensor array 10 is at the position indicated by the thick line 16, the detected signal has a maximum inversion interval of 6T (FIG. 7)).

However, when signals having such inversion intervals of 4T and 6T are recorded in the information area by, for example, the MFM modulation method, only signals with widths of IT, 1.5T, and 2T can be obtained in the information area. The signal in the information area can be clearly identified.

Thus, by scanning the sensor array 10, FIG.
) is detected, it can be determined that the reading position of the sensor array 10 is on track, and after the signal pattern of FIG.
If the signal pattern a) is detected, it can be determined that the reading position of the sensor array 10 has moved to a new track.

[Problems to be Solved by the Invention] However, in the conventional information reproducing method as described above, if there is dust or scratches on the bits, the bits in the high reflectance part will be damaged. If there are any scratches, it becomes impossible to detect the signal pattern shown in FIG. 8(b), and there is a problem in that it is impossible to identify that a new track has been moved.

[Means for Solving the Problems] The information reproducing method of the present invention has an identification area on an information track for separating and identifying it from an adjacent information track, and this identification area has a low reflection part and a high reflection part or In an information reproducing method of an optical information recording carrier having a pattern section in which a predetermined pattern consisting of a low transmittance section and a high transmittance section is formed, a signal when the pattern section is detected and the above J? The present invention is characterized in that information on a predetermined information track is reproduced by separating and identifying adjacent information tracks using a signal when a turn cannot be detected.

The information reproducing device of the present invention has a pattern section in which a predetermined /IP turn consisting of a low reflection part and a high reflection part or a low transmission part and a high transmission part is formed, and an identification for separating and identifying it from adjacent information tracks. means for irradiating light onto the identification area of an optical information recording medium having a region; a light detection means for detecting transmitted light or reflected light from the identification area; the light detection means and the optical information recording carrier; and means for detecting, from the output signal from the light detection means, a signal indicating the main turn portion and a signal indicating the absence of the pattern portion.

[Operation] The information reproducing method of the present invention determines whether or not it is possible to reproduce the information of the information track having the pattern portion, depending on whether or not a pattern portion in which a predetermined pattern is formed is detected. By making this determination, it is possible to reproduce information without being affected by dust, scratches, etc. in areas other than the pattern portion.

Note that if the pattern part is detected by detecting the low reflection area or low transmission area of the /4 turn part, the low reflection area that is resistant to dust and scratches (the part with dust and scratches is The pattern portion can be detected using only the low reflection area), and the accuracy of the detection can be improved.

Furthermore, if an optical information recording carrier is used in which the width of the turn portion in the direction perpendicular to the information alignment direction of the information track is shorter than the width of the track, a sensor array for reproducing information on the information track and a sensor array for reproducing the information on the information track can be used. The inclination with respect to the arrangement direction can be detected more reliably. In this case, when the information tracks of the information tracks are sequentially reproduced in the information arrangement direction of the information tracks, a signal when a pattern part is detected and a signal when the pattern part cannot be detected are as follows.
After obtaining a signal when the pattern part cannot be detected through alternating detection, if a signal is obtained when the pattern part is detected, it is determined that the system has moved to the next information track and the information on the information track is reliably read. Can be played.

The information reproducing device of the present invention is used for the information reproducing device of the present invention described above, and irradiates the identification area of an optical information recording medium with light, and optically detects the transmitted light or reflected light from the identification area. and from the output signal from this light detection means, a signal indicating the pattern portion and the putter/
The information is reproduced while determining whether or not the information on the information track is being reproduced accurately based on this detection signal.

[Example] Hereinafter, an example of the present invention will be described in detail using the drawings.

FIG. 1 is a signal waveform diagram for explaining the information reproducing method of the present invention.

FIG. 2 is a block diagram of the information reproducing circuit of the information reproducing apparatus of the present invention.

As shown in FIG. 2, when the optical card is set in a predetermined location, the sensor array 10 is driven by a control signal 108 from the sensor array driver 101. An analog waveform signal 10 corresponding to the image of the track on the optical card projected by the optical system is output from the sensor array 10.
7 enters the sensor array driver 101 and further enters the binarization circuit 102 as a signal 109. The signal 110 digitized by the circuit is sent to the identification area detection circuit 103.
, information demodulation circuit 104 and end bit detection circuit 105.

The identification area detection circuit 103 sends a signal 114 indicating an on-track state to the information demodulation circuit 104.

In addition, a signal 111 indicating the on-track state and a signal 111 indicating moving to a new track is transmitted to the circuit 1 including the information area 9.
Send to 06. The information demodulation circuit 104 synchronizes the data read clock in the preamble area and sends a signal 115 indicating synchronization to the identification area detection circuit. Also, after receiving the on-track signal 114 after synchronization, it determines the beginning of the information,
For example, a signal modulated by MFM modulation is demodulated and sent to the information acquisition circuit 106 as an information signal 112. The end bit circuit 105 detects the end bit and sends a signal indicating the end of the information and a signal 113 indicating that the track has moved to a new track to the information acquisition circuit 106. The information acquisition circuit 106 makes a judgment based on the signals 111, 112, and 113, and acquires a correct signal once from among the signals obtained by the sensor array 10 scanning one track multiple times.

Thereafter, the tracks are sequentially scanned to reproduce information.

Next, an information reproducing method of the present invention using the above information reproducing circuit will be explained with reference to FIG.

In FIG. 1, signal a shows a binarized signal at the time of on-track. Note that the signal 21a in the figure.

22 a e 23 a + 24 m + 30 m
+ 31 a indicates each area in the information track 4 in FIG.
, information area 23, end bit 24, start bit 3
These signals correspond to the 0° information part 31 and are obtained from each area.

When the information demodulation circuit 104 shown in FIG. 2 synchronizes the data read clock in the preamble area 21 (in this embodiment, only 6 bits are written for convenience), the signal
This signal has a level of "0".Signal C is a dirt signal that has a size within the range where the identification area 22 is detected when the falling edge of the signal C is "1" in the dirt range of signal C. ” level length (for example, by sampling consecutive 11# levels at a frequency faster than the data read clock and counting the number), the first time is 4 (actually, the range is a certain range, for example, 3.5T to 4). .5T.)
When measured, an on-track signal d is output. Signal e indicates f-) produced by on-track signal d.
The signal f is an information signal demodulated by the information demodulation circuit 104.

With the signal obtained as described above, the signal r−h
When a level of 11'' is detected for the first time within 30 minutes, it is determined as a start bit and the level of signal g is set to 10''.

On the other hand, when off-track, the "1" level of 4T in the binary digital signal disappears within the dirt of signal C,
The signal d remains at 1". Therefore, the f-) of the signal e is not generated, and the level of the signal g remains at "1". In other words, the signal g is By sampling after the position, if the level is "0", you can know that it is off-trunk.If the on-trunk signal was obtained in a scan after the scan that obtained this off-track signal, Then, it can be determined from this scanning that a new track is being scanned.

[Effects of the Invention] As described in detail above, according to the information reproducing method and information reproducing apparatus of the present invention, shadows of dust, scratches, etc. in areas other than the pattern portion can be removed! # Information can be reproduced without being completely lost, and malfunctions during reproduction can be prevented.

Note that if the pattern part is detected by detecting the low reflection area or the low transmission area of the pattern part, the low reflection area that is resistant to dust and scratches (the part with dust and scratches is the low reflection area). The pattern portion can be detected using only the area), and the accuracy of the detection can be improved.

Further, if an optical information recording carrier is used in which the pattern portion has a width in the direction perpendicular to the information alignment direction of the information track that is shorter than the width of the track, a sensor array for reproducing the information on the information track and a sensor array for reproducing the information on the information track can be used. The inclination with respect to the alignment direction can be detected more reliably. In this case, when the information tracks of the information track are sequentially reproduced in the information arrangement direction of the information track, a signal when a pattern part is detected and an equal sign when the pattern part cannot be detected are alternately detected. After obtaining the signal when the pattern part cannot be detected, if you obtain the signal when the pattern part is detected,
The information on the information track can be reliably reproduced by determining that the information track has moved to the next information track.

[Brief explanation of the drawing]

FIG. 1 is a signal waveform diagram for explaining the information reproducing method of the present invention. FIG. 2 is a block diagram of the information reproducing circuit of the information reproducing apparatus of the present invention. FIG. 3 is a schematic plan view showing an example of the configuration of an optical card. FIG. 4 is a partially enlarged view of the recording format of the optical card. FIG. 5 shows a schematic diagram of a device used for recording and reproducing the optical card as described above. FIG. 6 is a partially enlarged schematic diagram of the identification area of the optical card 1 shown in FIG. 4. FIG. 7 is a waveform diagram showing a binarized signal corresponding to the identification area shown in FIG. 6. 10: Sensor array, 101: Sensor array driver, 102: Binarization circuit, 103: Identification area detection circuit, 1
04: Information demodulation circuit, 105: End bit detection circuit,
106: Information acquisition circuit. Agent Patent Attorney Sekihei Yamashita Figure 1

Claims (5)

[Claims] (1) An identification area is provided on the information track to separate and identify it from adjacent information tracks, and this identification area is formed with a predetermined pattern consisting of a low reflection part and a high reflection part or a low transmission part and a high transmission part. In the method for reproducing information from an optical information recording carrier having a pattern portion, the information track is separated and identified from an adjacent information track using a signal when the pattern portion is detected and a signal when the pattern portion is not detected. An information playback method for playing back information on an information track. (2) The information reproducing method according to claim 1, wherein the pattern portion is detected by detecting a low reflection area or a low transmission area of the pattern portion. (3) The information reproducing method according to claim 1, using an optical information recording carrier in which the pattern portion has a width in a direction perpendicular to the information arrangement direction of the information track that is shorter than the width of the track. (4) The method according to claim 1, wherein, after obtaining a signal when the pattern portion cannot be detected, a signal when the pattern portion is detected is obtained to determine that the information track has moved to the next information track. Information reproduction method. (5) having a pattern part in which a predetermined pattern consisting of a low reflection part and a high reflection part or a low transmission part and a high transmission part is formed;
and a means for irradiating light onto the identification area of an optical information recording medium having an identification area for separating and identifying from adjacent information tracks; a light detection means for detecting transmitted light or reflected light from the identification area; means for relatively moving a detection means and the optical information recording carrier; means for detecting a signal indicating the pattern portion and a signal indicating the absence of the pattern portion from the output signal from the light detection means; An information reproducing device having: