Classifications

• • G—PHYSICS
  • G11—INFORMATION STORAGE
  • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
  • G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
  • G11B7/002—Recording, reproducing or erasing systems characterised by the shape or form of the carrier
  • G11B7/0033—Recording, reproducing or erasing systems characterised by the shape or form of the carrier with cards or other card-like flat carriers, e.g. flat sheets of optical film

Definitions

• the present invention provides for each track on which data is recorded, a light with an optically detectable mark to determine the position of the track. Regarding force reading devices.
• the light signal has an information recording signal on each of a plurality of parallel tracks. It is recorded so that it can be read optically by the g column in the table.
• an optically readable mark is formed at one end of each track at a position corresponding to that track.
• the light power 6 is transmitted in the width direction of the track, and the information of each track is stored in an array of charge-accumulating photodetectors (shown in the figure). Not detected), it is detected together with the relevant mark.
• This detection content is electrically driven and extracted. This electrical scan was performed several times at different positions on the 1 * track, and FIG.
• the detection signal 8 of the mark 4 fluctuates stepwise upward and downward depending on the detection position. Predict this signal 8
• the track displacement signal 9 is obtained by comparison with the determined judgment level 7, and the predetermined position in the track width direction based on the signal 9 is obtained. To obtain valid read information.
• the track displacement signal is determined by various factors such as the level of the judgment level, the sensitivity of the detection element, and the optical loss of the optical system. If the rise and fall times of the data fluctuate, it may be difficult to determine the proper timing to capture valid data. There was a problem.
• An object of the invention is to provide a light-powered reader capable of obtaining a constant track displacement signal irrespective of the various causes described above.
• the invention has a mark section at the end or inside of a plurality of data tracks parallel to each other, which can be read by optical reading means.
• Part consists of the first and second marks that are different in the track direction, and the first and second marks are separated by the track interval.
• An optical power reading device which is arranged at a certain interval and in a different phase relationship according to said optical power reading device, said optical power reading device being relative to said optical reading means.
• the reading device of the present invention comprises a light detecting means for optically detecting the data tracks and the corresponding marks, and a light detecting means for the optical reading means.
• the detection content of the light detection means is electrically scanned while the light power is relatively moved in the width direction of the track.
• First and second extraction and holding means for extracting and holding the detection signals of the first and second marks, respectively, and the first and second extractions
• First and second low-pass filters for extracting low-pass signals output from the output / holding means, and the first and second filters; That make up Ri by the comparator you compare both the output of the data ⁇ You can in this and force S.
• the optical head to which the present invention is applied is a mirror that can be read by optical reading means at the end or inside of a plurality of parallel data tracks.
• a mark portion, and the mark portion has a different position in the track direction from the first and second marks, and the first and second marks have different positions. These marks are arranged at regular intervals synchronized with the track intervals and in different phase relationships.
• the first mark column and the second mark column are adjacent. The reason is that the proximity This is because the change in light amount due to the change in position can be almost ignored.
• the optical card which is the premise of the invention unlike the above-mentioned known example, it is not necessary to provide a gap between the data tracks to be connected and disengaged. . Thus, the data recording density is improved.
• both the first and second marks are affected even if the light amount loss of the optical system, the sensitivity of the detecting element, etc. change.
• Fig. 1 is a block diagram of the circuit of the reading device of the present invention
• Fig. 2 (A) is an enlarged view of a main part of an optical card applied to the present invention.
• FIG. 2B is an explanatory diagram for explaining the timing of a read circuit signal corresponding to the optical card.
• FIG. 3 is a schematic diagram of an example of a light source to which the undiscovered is applied.
• Fig. 4 is an enlarged view of the main part of Fig. 3,
• FIG. 5 is a schematic view of the mechanism of the reading device according to the invention.
• Fig. 6 is a schematic diagram of a conventional optical card.
• FIG. 7 (A) is an enlarged view of the main part of a conventional optical card
• Fig. 7 (B) illustrates the timing of the readout circuit signal corresponding to the optical card.
• Explanation diagram for FIG. 8 (A) is an enlarged view of a main part of another optical card applied to the present invention.
• FIG. 8 (B) is an explanatory diagram for explaining the timing of the read circuit signal corresponding to the light source.
• FIG. 9 (A) is an enlarged view of a main part of still another light source applied to the present invention.
• FIG. 9 (B) is an explanatory diagram for explaining the timing of the reading circuit signal corresponding to the optical card.
• FIG. 3 has a plurality of rows of bands 32 on its surface.
• Each of the bands 32 has a data section 34 and a mark section 3. 6 and strength.
• This one band 32 as shown in FIG. 4, consists of a large number of tracks 38 that have been inscribed.
• the direction of track 38 is perpendicular to the longitudinal direction of the band.
• the mark section 36 of each band 32 has marks 1 and 2 whose positions are alternately different in the track direction for each track.
• the mark section 36 is provided at the end of the track 38, at the Z or inside thereof, and at a force S, the mark within one mark section 36.
• mark 1 and mark 2 be in close proximity as shown.
• the invention can be applied to a light source where the track and mark have a different phase relationship, as shown in Fig. 8 (A). Also, if recording and detection are possible, as shown in Fig. 9 (CA), each track has both Mark 1 and Mark 2 provided. Applicable.
• a reading device 40 With such a light source 30, recorded information is read by a reading device 40 as shown in FIG.
• the light from the light-emitting element 42 is focused on the card 30 through a lens 46, and the reflected light is passed through a lens 48 to detect the light.
• Received by array 44 for example, charge-coupled device: CCD).
• the light beam 30 is sent from the one end to the other end in the band direction by the transmission mechanism 47, and all the information of one band 32 is read. .
• the moving speed of the light source 30 should be a speed that allows data to be read multiple times per track 1 ⁇ .
• the reading of a different band 32 is performed by moving the optical system 45 in a direction perpendicular to the band 32. Since it is sufficient that the above operation is relatively achieved between the optical system 45 and the light source 30, either of the two may be moved.
• FIG. 1 shows a circuit configuration of the reader.
• This circuit includes a photodetector array 44, a scanning circuit 50, Mark 2 and Mark 1 signal extraction circuits 51, 52, sample hold circuits 53, 54, low-pass filters 55, 56, It consists of a comparator 57.
• the light detection element array 44 is electrically scanned by the running means 50 and the detection information is read. From the detection information, the light and dark signals (detection signals) of Mark 2 and Mark 1 are discharged by the oil discharge circuits 51 and 52, respectively. It is held by the sample hold circuits 53 and 54. As described above, since the electrical scanning is performed a plurality of times at different positions in the width direction of the track 1 *, a sample hold time is required. The light and dark signals of the marks 1 and 2 held in the paths 54 and 53 fluctuate up and down in a stepwise manner as shown in FIG. 2 (B). This input signal is converted into a smooth waveform by the low-pass filters 55 and 56, and then compared by the comparator 57.
• the result of this comparison is a track displacement signal for defining the track boundary in the * embodiment. Based on this track displacement signal, it is possible to determine valid data acquisition timing. For example, the number of scans is counted from the time when the rising and falling of the displacement signal is reset, and the predetermined number of times of running data is set as valid data. Can be imported to Next, the light power of FIG. 8 (A) will be described. As described above, in the optical power supply shown in FIG. 7A, the mark section 36 is displaced from the data section 34, so that the mark The detection signal of the clock also shifts with respect to the data track, as shown in FIG. Therefore, the track displacement signal in this case rises or falls inside the track, not at the boundary of the track. Therefore, if the above phase relationship is properly determined, it is possible to determine effective data acquisition timing without counting the number of scans. Wear .
• both the mark 1 and the mark 2 are provided for each track, as described above.
• the detected signal has twice the frequency, and the frequency of the track displacement signal is also doubled.
• the falling edge of the track displacement signal can be used as a reference for valid data acquisition.

Landscapes

• Optical Recording Or Reproduction (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=17231010

Family Applications (1)

Country Status (2)

Families Citing this family (1)

Citations (2)

• 1987
  • 1987-10-06 JP JP62251990A patent/JPH0194534A/ja active Granted
• 1988
  • 1988-10-06 WO PCT/JP1988/001020 patent/WO1989003576A1/ja unknown

Patent Citations (2)

Also Published As

Similar Documents

Legal Events