JPH0536112A - Optical card information reproducing device - Google Patents

Abstract

(57) [Summary] [Structure] The optical system irradiates a plurality of information tracks on the optical card 1 with light and reflects the reflected light from the optical card 1 to the information detector 2 of one photodetector 11. The light is focused on the photodetector 11 so that the two cells correspond to each other. The correction circuit uses the optical card 1 to set the cell difference signal from the photodetector 11 to zero.
The objective lens 9 and the optical head 5 are driven. The reproduction circuit
Information of a plurality of information tracks on the optical card 1 is simultaneously reproduced by the sum signal of the cells from the photodetector 11. [Effect] Information of a plurality of information tracks on an optical card can be reproduced simultaneously and accurately.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical card information reproducing apparatus for optically reproducing information from an optical card.

[0002]

2. Description of the Related Art As one of optical card formats,
It is well known that an information track is formed in the longitudinal direction of an optical card as shown in FIG. An optical card information reproducing apparatus for reproducing information from such an optical card irradiates the information track of the optical card with light from a light source in the optical head, and the reflected light is read by a photodetector in the optical head. Is becoming When the format of the optical card is as described above, the relative movement between the optical card and the optical head becomes a linear reciprocating movement, and it takes a lot of time if the optical head reproduces information one track at a time.

Therefore, conventionally, in order to increase the reproduction speed for an optical card, light from a light source in an optical head is applied to a plurality of information tracks of an optical card, and the reflected light is reflected by, for example, a CCD.
Photodetector 1 having a plurality of cells 14 such as a line sensor
3 (see FIG. 5), and as shown in FIG. 5, one cell 14 of the photodetector 13 corresponds to one information track of the optical card to simultaneously reproduce information of a plurality of information tracks. I am trying to. In addition, FIG.
FIG. 11 is a diagram in which an information track of an optical card is imaged on a photodetector in an optical head of a conventional optical card information reproducing apparatus. In the figure, 19 is an information pit image, arrow 15 indicates the optical card scanning direction (direction in which the information track of the optical card extends), and the information track 4 of the optical card 1 (see FIG. 2) and the optical track. The cells 14 of the detector 13 have a one-to-one correspondence.

[0004]

However, in the simultaneous reproduction method of a plurality of pieces of information of an optical card by the above-mentioned conventional optical card information reproducing apparatus, when the optical card 1 itself is mounted on the apparatus and the optical card 1 is mounted on the apparatus. Due to the positional deviation of the information detector 4 and the like, a relative positional deviation between the cell 14 of the photodetector 13 and the information track 4 occurs. In particular, it is difficult to accurately match the angle between the information track 4 direction of the optical card 1 and the arrangement direction of the cells 14 of the photodetector 13, and while the optical card 1 and the optical head are relatively moved in the reproducing direction. Then, the information track 4 and the cell 14 are displaced. Therefore, there is a problem in that accurate information cannot be reproduced. The purpose of the present invention is to
An object of the present invention is to provide an optical card information reproducing apparatus capable of accurately and simultaneously reading a plurality of information even if the information track of the optical card and the photodetector are misaligned or tilted.

[0005]

The optical card information reproducing apparatus of the present invention is an optical card information reproducing apparatus capable of simultaneously reproducing a plurality of information tracks from an optical card having a plurality of information tracks linearly by one scanning. A photodetector having twice as many cells as information tracks that can be reproduced by one scan;
An optical system that irradiates a plurality of information tracks of an optical card with light and collects reflected light from the optical card on the photodetector so that two cells of the photodetector correspond to one information track. A correction means for detecting a relative displacement between the information track of the optical card and the photodetector based on the output from the photodetector and performing control to correct the displacement, and an output from the photodetector And reproducing means for simultaneously reproducing information on a plurality of information tracks on the optical card.

[0006]

In the optical card information reproducing device having the above structure, the optical system irradiates a plurality of information tracks on the optical card which can be reproduced simultaneously by one scanning, and reflects light reflected from the optical card into one information. The light is focused on the photodetector so that the two cells of the photodetector correspond to the track. The correction means detects a relative positional deviation between the information track of the optical card and the optical detector based on the output from the optical detector, and performs control to correct the positional deviation. The reproducing means simultaneously reproduces information on a plurality of information tracks on the optical card based on the output from the photodetector. Thus, even if the information track of the optical card and the photodetector are misaligned or tilted, a plurality of pieces of information can be read accurately and simultaneously. Further, if the correction unit detects the positional deviation at a plurality of points and performs the positional deviation correction control, the positional deviation can always be accurately corrected even if the optical card has defects, scratches, dust, or the like. ..

[0007]

Embodiments of the present invention will now be described with reference to the drawings. FIG. 2 is a partially enlarged plan view showing an embodiment of the optical card. In the figure, the optical card 1 is provided with an information recording area 2. In the information recording area 2, a plurality of information tracks 4 are linearly recorded.
The information track 4 is a row of information pits 3 arranged in the longitudinal direction of the optical card 1.

In the figure, 5 is a plurality of information tracks 4
Is an optical head for simultaneously reproducing the information. The optical head 5 includes a light source 6 for illuminating the information track 4 on the optical card 1, a lens 7, a beam splitter 8, and
It is composed of an objective lens 9, an imaging lens 10, and a photodetector 11. Here, the lens 7 supplies the light from the light source 6 to the beam splitter 8. Further, the beam splitter 8 transmits the light from the lens 7 to the objective lens 9
Optical card 1 supplied to and from the objective lens 9.
The reflected light from the upper information track 4 is supplied to the imaging lens 10. Further, the imaging lens 10 focuses the reflected light supplied from the beam splitter 8 on the photodetector 11. Further, the photodetector 11 has a cell number twice as many as the number of information tracks that can be reproduced by one operation. Then, two cells of the photodetector 11 correspond to one information track 4 on the optical card 1. The optical system of the present invention is composed of a light source 6, a lens 7, a beam splitter 8, an objective lens 9 and an imaging lens 10 here, and a plurality of information tracks to be reproduced by the optical card 1. 4 is irradiated with light, and the reflected light from the optical card 1 is focused on the photodetector 11 so that two cells of the photodetector 11 correspond to one information track 4.

Although not shown in the figure, the correction circuit as the correction means of the present invention is the same as the photodetector 1.
The information track 4 of the optical card 1 is supplied by using a cell difference signal (a relative positional deviation signal between the information track 4 on the optical card 1 and the photodetector 11) according to a predetermined combination, The optical card 1, the optical head 5, or the optical head 5 is used to constantly detect the relative positional deviation between the optical detector 1 and the photodetector 11 and correct the positional deviation, that is, the cell difference signal is always zero. It drives the objective lens 9 therein. Although not shown in the figure, the reproducing circuit as the reproducing means of the present invention is the reproducing circuit.
The information of a plurality of information tracks 4 on the optical card 1 is reproduced at the same time based on the output (sum signal of cells) supplied from the optical card 1.

FIG. 1 is a schematic block diagram showing an embodiment of an optical card information reproducing apparatus according to the present invention. In the figure,
The light emitted from the light source 6 in the optical head 5 is reflected by the lens 7,
Optical card 1 through beam splitter 8 and objective lens 9
The light is focused over a plurality of information tracks 4 that can be simultaneously reproduced by one scan. The reflected light is again focused on the photodetector 11 via the objective lens 9, the beam splitter 8 and the imaging lens 10. Meanwhile, optical card 1
Is driven by an optical card loading mechanism (not shown) in a direction parallel to the information track 4 (direction of arrow 16). Then, the reproducing circuit outputs the output (2
Information of a plurality of information tracks 4 to be reproduced is simultaneously reproduced based on the sum signal of one cell). Next, when it is desired to reproduce the information on the other plurality of information tracks 4, the optical head 5 is moved in the direction perpendicular to the information tracks 4.

Simultaneous reproduction of information on a plurality of information tracks 4 will be described below. FIG. 3 shows a state in which the information track 4 of the optical card 1 is imaged on the photodetector 11. In FIG. 3, 12 is a cell of the photodetector 11, 18 is an information pit image (hatched portion), and 17 is an optical card scanning direction. As can be seen from FIG. 3, here, the size of the cells 12, the spacing, and the imaging magnification of the optical system are preset so that each information track 4 is located at the center of the two cells 12 of the photodetector 11. .. The image forming magnification of the optical system can be easily set by appropriately selecting the objective lens 9 and the image forming lens 10.
The information recorded on the optical card 1 is supplied from the photodetector 11 to the reproducing circuit as a sum signal of two cells 12, for example, the cells 12a and 12b and the cells 12c and 12d,
Played here.

Next, when the information track 4 and the photodetector 11 are displaced or tilted relative to each other, the information track 4 of the optical card 1 is imaged on the photodetector 11 as shown in FIG. .. In FIG. 4, 12 (12a to 12j) is a cell,
Reference numeral 18 is a pit image (hatched portion). When such a positional deviation occurs, the reproducing circuit cannot accurately reproduce information by the sum signal of the two cells 12 as described above.
However, in the present invention, the correction circuit constantly detects the difference signal between two cells, for example, the cells 12e and 12f in a predetermined combination, so that the relative position between the information track 4 and the photodetector 11 is detected. The displacement is always detected, and the displacement of the position is always zero, that is, the difference signal between the two cells, for example, the cells 12e and 12f, is always zero. Drive the card 1. As a result, the reproducing circuit enters a state in which the information of the plurality of information tracks 4 can be reproduced accurately at the same time, as shown in FIG.

As the output supplied from the photodetector 11 to the correction circuit, the difference signals of the cells 12 formed by a plurality of predetermined combinations, for example, the difference signals of the cells 12b and 12i, the cells 12h and 12c are output. As in the case of the difference signal, by selecting a plurality of signals, the correction circuit can detect a relative displacement signal (cell 12) between the information track 4 and the photodetector 11 from a plurality of locations.
The difference control signal of 1) is detected, and the above-described correction control can be performed based on the detected signal. Therefore, even if a part of the optical card 1 has a defect, a scratch, a dust, or the like, the positional deviation can be always corrected. The present invention is not limited to this embodiment, and various applications and modifications are conceivable without departing from the gist of the present invention.

[0014]

As described above, according to the present invention, the following effects can be obtained. (1) The number of cells of the photodetector is made twice as many as the number of information tracks read in one scan, and two cells are made to correspond to one information track, and the reproducing means outputs from the photodetector. The information of a plurality of information tracks on the optical card is reproduced at the same time based on the (sum signal of two cells), and the correction means outputs the difference between the two cells due to the output from the photodetector (a predetermined combination). Since the positional deviation between the information track and the photodetector is always detected and corrected based on the signal), the information of a plurality of information tracks can be reproduced simultaneously and accurately. (2), the correction means detects a relative positional deviation between the information track of the optical card and the photodetector at a plurality of points,
When performing the position misalignment correction control,
Even if the optical card has defects, scratches, dust, etc., it is always possible to accurately correct the positional deviation.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment of an optical card information reproducing apparatus according to the present invention.

FIG. 2 is a partially enlarged plan view showing an embodiment of an optical card.

3 is an explanatory diagram showing a state in which an information track 4 of the optical card 1 is imaged on the photodetector 11 of FIG.

FIG. 4 is an explanatory diagram showing a state in which an information track 4 of the optical card 1 having a relative positional deviation with the photodetector 11 is imaged on the photodetector 11 of FIG.

FIG. 5 is an explanatory view showing a state in which an information track 4 is imaged on a conventional photodetector 13.

[Explanation of symbols]

 1 Optical Card 3 Information Pit 4 Information Track 5 Optical Head 6 Light Source 7 Lens 8 Beam Splitter 9 Objective Lens 10 Imaging Lens 11 Photodetector 12, 12a to 12j Cell

Claims (3)

[Claims] 1. An optical card information reproducing apparatus capable of simultaneously reproducing a plurality of information tracks from an optical card having a plurality of linear information tracks by one scanning, and twice the number of information tracks which can be reproduced by one scanning. And a plurality of information tracks of the optical card, and the reflected light from the optical card is reflected by one of the two cells of the photodetector for one information track. An optical system for focusing on the photodetector so as to correspond thereto, and a relative positional deviation between the information track of the optical card and the photodetector is detected based on the output from the photodetector, and the position is detected. It is provided with a correction means for performing control to correct the deviation, and a reproduction means for simultaneously reproducing the information of the plurality of information tracks on the optical card based on the output from the photodetector. Card information reproducing apparatus. 2. The correcting means detects relative positional deviation between the information track of the optical card and the photodetector at a plurality of points, and performs correction control of the positional deviation. Item 1. The optical card information reproducing device according to Item 1. 3. The optical card information reproduction according to claim 1, wherein the correction control of the positional deviation by the correction means is performed by driving the optical card or the optical head or an objective lens in the optical head. apparatus.