JPH01124124A - Information reproducing device and information recording carrier - Google Patents

Abstract

PURPOSE:To miniaturize and thin a device by providing a reading part corresponding to the zone of an information track, taking the reading part as the lens array arranging a lens in one dimensional array shape and reading the information of an information track by the lens corresponding to the respective in the state of reducing the crosstalk among the images of each lens. CONSTITUTION:The information track made by arranging informations one dimensionally is arranged in plural lines respectively in the length direction and the direction orthogonal to the length direction and the information is read by the one dimensional lens array 13 corresponding to the zone S of plural information tracks arranged in the length direction of the information track. The pitch in the length direction of the information track coincides with that of a lens array and the length of the information track is made shorter than the pitch of the lens array. The signal of high quality is thus obtd. by evading the reduction of the resolving power by the overlap of images among lenses, reproducing speed and efficiency are improved and a reproducing device can be miniaturized and thinned.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an information reproducing device and an information recording carrier intended for increasing the density of information recording, miniaturizing and simplifying the mechanism, and increasing the speed of reproduction. be.

[Prior Art] In recent years, information has been reproduced using optical information recording carriers such as optical files and compact discs. Furthermore, recently, information reproduction using a card-shaped optical information recording carrier, a so-called optical card, which is more portable than these recording carriers and has a relatively large capacity, has been attracting attention.

FIG. 11 is a schematic plan view of an optical card C showing an example of the recording format of an information track.A recording area S is provided on the optical card C, which is a record carrier, and this recording area S is arranged in a plurality of arrays. Each band B is separated by a reference line R. Further, each band B is formed by arranging a large number of information tracks T, and each information track T has an information capacity of about several tens to 100 bits. Note that the arrow X is the moving direction of the optical card C during reproduction, and the arrow Y is the information reading scanning direction by the optical head during reproduction.

FIG. 12 is a schematic configuration diagram of an apparatus for reproducing an optical card C having the above-mentioned recording format. The information recorded on this optical card C is read and reproduced by the optical card 2 for each track T.

First, a light beam emitted from a light source 3 such as an LED is transmitted to an optical system 4.
The light is focused by and illuminates the optical card C. An image of the track T of the optical card C is formed onto a one-dimensional sensor array 6 by an imaging optical system 5.

Since the optical card C moves in the direction of the arrow X, the image of the information track T on the sensor array 6 changes correspondingly. In the sensor array 6, reading scanning is performed several times while each information track T is imaged on the sensor array 6, and data that can be read correctly is selected and employed. In this way, the recorded information of several information tracks T in the band B is reproduced, and when this is completed, the optical radar 2 is moved as appropriate in the direction of the arrow Y to reproduce other target bands. Information track T in B is sensor array 6
The recorded information is reproduced in the same manner as described above.

By the way, in the above-mentioned playback device, the sensor array 6 is configured to be somewhat longer than the length corresponding to one information track T so that each information track T is read. Arrow X against card C
By relatively moving in the direction of arrow Y, a desired information track T is accessed and information is read. For this reason, a mechanism and control means are required for reciprocating the optical card C relative to the sensor array 6 in two directions, the arrow X direction and the arrow Y direction.

For example, the width of one band B of the optical card C, that is, the length of the information track T, is 800 m, and the width of the recording area S is about 3 m.
If it is 0 mm, the total number of bands B is 37 trees, and in order to reproduce the information of the information tracks T of all these bands B, it is necessary to read the information only during relative movement in one direction in the arrow X direction. is reciprocated 37 times, and if reading is performed during relative movement in both directions of the arrow X, it will be reciprocated 19 times. Furthermore, relative movement in the direction of arrow Y is also performed, and a two-dimensional relative movement means is required for this purpose.

[Problems to be Solved by the Invention] Due to the two-dimensional relative movement during playback as described above, there may be a slight deviation in alignment between the optical card C and the sensor array 6.
In other words, a skew phenomenon often occurs, which is a problem. Furthermore, the mechanical two-dimensional relative movement during playback as described above takes a relatively long time, and some of this movement does not involve reading information, such as relative movement in the direction of arrow Y. It is quite difficult to improve the speed and efficiency of information reproduction. Furthermore, the optical head 2 also becomes large, making it especially difficult to reduce the thickness of the device.

[Objects of the Invention] The objects of the present invention are that the configuration of the means for relative movement between the information recording carrier and the information detector is relatively simple, the device can be easily made smaller and thinner, and the playback speed can be increased. and to provide an information reproducing device with excellent reproduction efficiency.

Another object of the present invention is to provide an information recording carrier suitable for exclusively utilizing the performance of the above information reproducing device.

[Summary of the Invention] The gist of the specific invention for achieving the above-mentioned object is that information tracks each having information arranged in one dimension are arranged in plural rows in the length direction and in a direction perpendicular to the length direction. In an information reproducing apparatus that optically reads the information from a card-shaped information recording carrier, a reading section corresponding to the area of the plurality of information tracks arranged in the length direction of the information track is provided, and the reading section includes a lens. The information reproducing apparatus has a lens array arranged in a one-dimensional array, and information on the information track is read by the corresponding lenses while reducing crosstalk between images of the respective lenses.

The gist of the present invention related to the above-mentioned specific invention is to arrange a plurality of information tracks in which information is arranged one-dimensionally in the length direction and in a direction orthogonal to the length direction, and to transfer the information to the information track. A card-shaped record carrier that is read by a one-dimensional lens array corresponding to the area of the plurality of information tracks arranged in the longitudinal direction, wherein the pitch in the longitudinal direction of the information tracks is equal to the pitch of the lens array.
Accordingly, the information recording carrier is characterized in that the length of the information track is smaller than the pitch of the lens array.

[Embodiments of the Invention] The present invention will be described in detail based on embodiments illustrated in FIGS. 1 to 10.

FIG. 1 is an explanatory diagram of the positional relationship between the optical card C and the reading area of the optical helad 10, FIG. 2 is a partially enlarged view thereof, and FIG. 3 is a perspective view of the information reproducing means. Here, the optical card C has a format similar to that shown in FIG. 11 described above. Additionally, the optical head 10 has a length along the arrow Y direction that is greater than or equal to the width of the recording area S, so that information in the recording area S in the arrow Y direction can be read all at once.

As shown in FIG. 3, the optical herad 10 is structurally composed of a long light source 11, a long mirror 12 for bending a light beam, a rod lens array 13 for imaging, and a sensor array 14. . The elongated light source 11 may be, for example, an LED array and a semi-cylindrical lens integrated into one, and which has a uniform linear light intensity distribution. As the rod lens array 13, gradient index rod lenses are used which are arranged long in one dimension.As will be described in detail later, the problem occurs when the images of each rod lens are overlapped when arranged in multiple rows. This avoids the reduction in resolution that would otherwise occur. The sensor array 14 is, for example, a large number of amorphous silicon sensors arranged one-dimensionally in the direction of the arrow Y. For example, in this embodiment, the size of the sensor cells constituting the sensor array 14 is equal to one bit of the optical card C. Set to 174,
It is constructed so that one bit is sampled by four cells, and the lateral magnification of the rod lens array 13 is set to equal magnification in order to downsize the optical head 10 in the optical axis direction.

FIG. 4 is a side view of the optical head lO shown in FIG.
By bending the light beam of the imaging system approximately parallel to the surface of the optical card C by the bending mirror 12, the optical helmet 10 is made thinner.

Next, FIGS. 5 to 7 show side views of modified embodiments of the optical head 10, respectively. FIG. 5 shows that the light beam 10 is further made thinner by bending not only the light beam of the imaging system but also the light beam of the illumination system, and a long brism mirror 15 is used as a means for bending the light beam. The light beam bending means of the illumination system and the imaging system are integrated. Note that the other components are the same as those in FIG. 4, so their explanation will be omitted.

In FIG. 6, a long beam splitter 16 is used as the first light beam bending means, and a long prism mirror 17 is used as the second light beam bending means. Since the beam splitter 16 has the function of aligning the optical axes of the illumination system and the imaging system, assembly adjustment in the angular direction is easier than in the previous embodiment. In other words, if the optical axis has an angle with respect to the normal line of the optical card C as in the previous example, a special tool jig and observation system tailored to that angle will be required during actual assembly adjustment. However, the structure shown in FIG. 6 can be assembled and adjusted using simple tools. Also, the second
Since the elongated prism mirror 17 is used as a light beam bending means, this is disadvantageous in making the optical head 10 thinner, but since the length in the direction of arrow X is shortened, there is an advantage that the device can be made smaller. Furthermore, the implementation of the driving circuit for the sensor array 14 is much easier than in the previous two embodiments. In other words, in the previous embodiment, the sensor array 14 and the optical card C are brought closer together due to the thinning, and considering the warping of the optical card C, etc.
Although the circuit had to be mounted on one side of the sensor array 14, as shown in FIG.
By inserting the light beam bending means immediately before the light beam bending means, it is possible to realize a small optical head 10 that is easy to mount without significantly impairing its thinness.

However, in the embodiment shown in FIG. 6, since the long beam splitter 16 is used as the beam bending means, the amount of light reaching the sensor array 14 is significantly reduced, and there is a risk that the reading speed will be slowed down. Therefore, in FIG. 7, the elongated light source 11 is a waveguide-entangled LED that emits linearly polarized light, or a semiconductor laser array, and the elongated polarizing beam splitter 18 is used as the first light beam bending means.

A long quarter wavelength plate 19 is inserted between the optical card C and the optical card C, with the axes aligned. Therefore, the incident light on the optical card C is converted into circularly polarized light, and when reflected from the optical card C, it passes through the quarter-wave plate 19 again and becomes linearly polarized light rotated by 90 degrees with respect to the polarized light of the elongated light source 32. Since the light is converted and reflected by the long polarizing beam splitter 18 toward the imaging system, it is possible to achieve almost 100% light utilization efficiency. As described above, in the embodiment shown in FIG. 7, it is possible to increase the amount of light without impairing the features of the embodiment shown in FIG. 6, and the reading speed can be improved. Although the optical head 10 in this case is somewhat expensive, it can be applied to high-end machines as a high-speed type.

Next, a method for reducing crosstalk between the lenses of the imaging rod lens array 13 used in the above embodiment will be described in detail. FIG. 8(a) is a developed view of the imaging system of the optical herad 10, with the light beam bending means omitted. For example, in the case of a gradient index lens, the field of view radius Y
O is expressed by the following equation (1), where rO is the lens radius, ZO11 is the lens length, and P is the meandering period length within the lens.

YO= -ro・5ec(ZO・π/P)
...-(1) For a lens with an aperture angle of 20 degrees, P=
Since it is 14 mm, assuming 1 magnification as equal magnification, the field of view radius Y
To make 90% of O without image overlap,
It is sufficient if ro/YO≧0.9, so ro/YO=0
．． 9 to get ZO=12mm aro==O-5
m m (7) If L/7s, YO=0.56
mm, so the image overlap compensation sphere is 0,06 m
If m is excluded, effective image height without overlap Y1 = 0
, 44 mm is obtained. Therefore, in this case, the width is ±0.44 mm within 1 mm of the information dock T, and the width is 0.88 mm.
If information is recorded only within the effective track width TB,
A high quality signal can be obtained from the elongated light source 11 without overlapping images.

FIG. 8(b) shows an output waveform diagram of the sensor array 14 when a low reflectance density like - is recorded as dummy data in the invalid area within the track T. In this case, it is necessary to match the positional relationship between the track T and the rod lens array 13 in the direction of the arrow Y, but the position can be easily adjusted with an accuracy of about 50 g, m. Note that although a -like low reflectance density is used here as dummy data, it is of course not limited to this, and any pattern that can be easily identified as a dummy may be used.
They may be recorded at intervals.

FIGS. 9 and 10 show other methods of reducing crosstalk. First, in FIG. 9(a), by making the lateral magnification of the imaging system smaller than 1, the image of each lens constituting the lens array 13 becomes the sensor cell 14a of the sensor array 14.
For example, if the magnification is set to about 1/2, images of two tracks each with a width of 2.YO are formed on the sensor array 14.

In this way, since there is no need to provide an invalid area within the track T, not only is there no reduction in capacity, but also the positioning accuracy between the track T and the imaging rod lens array 13 does not need to be coarse.However, the optical card In order to secure four samples of the sensor cell 14a for one bit on C, it is necessary to make the sensor cell 14a small.

FIG. 9(b) shows a part of the output waveform of this sensor array 14, which is approximately ±Y1 (width 2·YO) above the image height YO (width 2·YO).
Information about the track T is detected in the Yl) area.

In FIG. 10, crosstalk between each image is reduced by providing a field stop 20 between each lens of the imaging rod lens array 13. The total lateral magnification is approximately the same as in Fig. 8, but the rod lens array 13
An inverted real image is formed at the center of the lens length, and the magnification m of this inverted real image is expressed by the following equation (2).

m;-1/((4π2/P2)11N02・L12+1
) - (2) Here, NO is the axial refractive index of the gradient index rod lens. In the case of a lens similar to that shown in FIG. 8, the distance L1 from the entrance end surface of the lens to the optical card C is expressed by the following equation (3).

L1= (P/(2π・No)) ・tan(Zoπ
/ P) ・”(3) Here, if NO-=1, 64, the L1 key is 0.66 mm, so the magnification of the image at the center position of the rod lens array 13 is m = −0, 9. Become.

Therefore, the length direction of the information track T of the field diaphragm 20, that is, the size in the direction of the arrow Y, is defined as (information track length)・(−
m)=0.9 mm, it is possible to eliminate crosstalk of the image on the sensor array 14 of the information track T.

Note that here, since the image is read out using the -dimensional sensor array 14, the effective image height in the width direction of the information track T, that is, in the arrow X direction, is limited to the size of the sensor array 14 in the arrow X direction. At most, it is several ILm to several hundred +ILm. Therefore, the field of view in the direction of arrow X is set to 200 gm, and the field diaphragm 20 is rectangular in order to have the effect of reducing noises such as backlight and flare ghosts.

Also, similar to the embodiment shown in FIG. 8, dummy data is inserted or a gap is provided between the reference lines R of the optical card C, so that the effective area within the information track T is slightly shorter than the track length. By this, the reference line R1 of the optical card C, that is, the information track T and the rod lens array 13
The alignment accuracy in the arrow Y direction can be made rougher. Although an example where the magnification is 1x is shown, the same effect can be obtained even if the magnification is 1x or less as shown in FIG. The shape does not need to be rectangular, and may be appropriately selected from circles, ellipses, polygons, etc. according to needs.

In this way, it is relatively easy to provide the field stop 20 in the middle of the rod lens array 13, and it may be processed in the rod state before or after providing the refractive index distribution, or it may be processed in the form of an array. This can be done after the rod lens array 13 has been arranged, or it can be done in the process of manufacturing the rod lens array 13 in one piece.

Note that the rod lens array 13 may be divided in the length direction of the rod, and the field stop 20 may be inserted between them. It can also be integrated by filling a transparent material with a distribution.

Next, the specific operation of the information reproducing apparatus of the present invention will be explained based on FIGS. 1 to 3. The optical card C is held and fixed by a holding and fixing means (not shown), and by moving the holding and fixing means or the sensor array 14 in the direction of arrow X, the recording area S of the optical card C and the optical head 10 are moved relative to each other. . Simultaneously with this relative movement, the output of the sensor array 14 corresponding to each information track T is obtained in the same manner as in the apparatus shown in FIG. 11, and reading scanning is performed in the sensor array 14 at appropriate time intervals. In this way, the information track T of band B is reproduced.

As shown in FIG. 2, the optical head 10 is generally positioned with a slight inclination to the length direction of the information track T, that is, the direction of the arrow Y. In other words, the optical card C is based on its outer shape. The optical card C is positioned and held and fixed by the optical card holding and fixing means of the playback device, but when manufacturing the optical card C, it is difficult to perfect the alignment between the outer shape and the recording format, and the playback device Because it is difficult to perfect the 7-alignment between the optical card holding and fixing means and the optical head 10 during manufacturing,
A slight inclination tends to occur in the correspondence between the recording format of the optical card C and the sensor array 14.

However, when the optical head 10 and the optical card C move relative to each other along the arrow X direction, the relative positional relationship between the optical head 10 and each band B in the arrow Y direction does not change too much. Therefore, if the separation area of each band B and track T, that is, the reference line R, is detected from the output of the sensor array 14, the timing of time division of the output of the sensor array 14 for each track T can be easily obtained. It is possible to reliably determine which band B the track T information belongs to.

Therefore, even with the waveforms shown in FIGS. 8(b) and 9(b), information on one track T can be reliably recognized. Furthermore, in the case as shown in FIG. 9, since there are some common parts in the images of adjacent rod lens arrays 13,
By using this, it becomes possible to predict and confirm the signal, and the detection of the truck T becomes reliable. Further, by assigning a track number to each track T, it is possible to accurately specify which track T the reproduction information belongs to.

This track number may be assigned to each band B, or may be a serial number for all tracks T. In this way, only either the optical card C or the sensor array 14 can be assigned in the direction of the arrow X. The information recorded on all the information tracks T in the recording area S of the optical card C can be reproduced by moving the door once in a fixed direction.

In the above-described embodiment, the optical head 10 is composed of three to four components, but it is of course possible to integrate these components by bonding or integral processing to realize a fixed head. Furthermore, although an example has been shown in which one bit of the optical card C is sampled by four sensor cells of the sensor array 14, the present invention is not necessarily limited to this, and in principle two or more sensor cells are sampled for one bit. The magnification of the imaging system can also be set arbitrarily in accordance with the above relationship and the relationship of image overlap. Furthermore, although an example of an amorphous silicon sensor is shown as the sensor array 14, any photodetector that can be arranged in a one-dimensional array may be used, and for example, a COD element that can form smaller sensor cells can also be used.

Further, although the refractive index distribution type low and drain lens array 13 arranged in one row was used as an imaging system, it is possible to prevent image overlap even when arranged in multiple rows. In addition, although the rod lens length was determined to form an erect real image, it is of course possible to shorten the lens length to form an inverted real image, in which case the optical path length can be reduced to approximately 1/2. can.

It is also possible to use a microlens array or the like. Furthermore, the angle is set so as to guide the specular reflection component of the illumination light beam to the imaging system, but it goes without saying that it is possible to set the angle to other than specular reflection as long as the amount of light is sufficient. The use of multiple long light sources becomes effective. In addition, although mirrors, prisms, and various beam splitters are used as the light beam bending means, the present invention is not limited to these, and the light beam bending means uses diffraction phenomena such as diffraction gratings and hologram elements. is also available,
The beam bending means itself is also not essential.

Further, although an example has been shown in which the information recording carrier is an optical card and the information detector is a photodetector, the present invention is applicable to information recording carriers in which information is recorded by the direction of magnetization, or information is recorded by uneven bits. The present invention can be applied in the same manner to the case where the information is recorded or the information reproducing device is a magnetic detector or the like.

[Effects of the Invention] As explained above, the information reproducing device and the information recording carrier according to the present invention can avoid deterioration in resolution due to image overlap between lenses, obtain high-quality signals, and can be used as an information recording carrier. It is only necessary to move relative to the information detector in one direction, which simplifies the structure of the means for driving and controlling the movement.Furthermore, since there are fewer movements that do not involve reading information, the playback speed can be reduced. and regeneration efficiency is improved. Furthermore, since the playback device can be made thinner and smaller, it becomes possible to incorporate it into various devices and realize a portable device.

[Brief explanation of the drawing]

The drawings show an embodiment of an information reproducing device and an information recording carrier according to the present invention, FIG. 1 is an explanatory diagram of the positional relationship between an optical card and an optical head, FIG. 2 is a partially enlarged view thereof, and FIG. 3 is an information reproducing apparatus. A perspective view of the device, FIGS. 4 to 7 are side views of other embodiments, FIGS. 8 and 9 (a) are configuration diagrams of the imaging system, and (b) are output waveforms thereof. 10 are block diagrams of the imaging system, FIG. 11 is a schematic plan view of the recording format of the optical card, and FIG. 12 is a block diagram of the information reproducing apparatus. 10 is an optical head, 11 is a long light source, 12 is a long mirror, 13 is a rod lens array, 14 is a sensor cell array, 14a is a sensor cell, 15 is a long prism, 16 is a long beam splitter, 17 is a long length 18 is a long polarizing beam splitter, 19 is a quarter-wave plate, 20 is an aperture, C is an optical card, S is a recording compensation sphere, B is a band, T is an information track, and R is a reference line. Patent applicant Canon Co., Ltd. Drawings Figure 1 Figure 2 Figure 4 Y-o X Figure 5 y, OX Figure 6-1Ox Figure 7 Y''''lE'X

Claims (1)

[Claims] 1. The information is optically recorded from a card-shaped information recording carrier in which a plurality of information tracks in which information is arranged one-dimensionally is arranged in a plurality of rows in the longitudinal direction and in a direction perpendicular to the longitudinal direction. an information reproducing device that reads information automatically, a reading section corresponding to an area of the plurality of information tracks arranged in the length direction of the information track, the reading section being a lens array having lenses arranged in a one-dimensional array; An information reproducing apparatus characterized in that information on the information track is read by the corresponding lenses while reducing crosstalk between images of the respective lenses. 2. A gradient index rod lens array is used as the lens array, and the rod is set so that the lateral magnification is approximately equal to the same magnification, and the object height and image height are 1 to 1.2 times 1/2 of the information track length. The information reproducing device according to claim 1, wherein the lens diameter and rod lens length are selected. 3. A graded refractive index rod lens array is used as the lens array, and the length of the rod is set so that the lateral magnification is less than 1:1 and the object height is the reciprocal of the lateral magnification, which is 1/2 of the information track length. The information reproducing device according to claim 1, wherein the lens diameter and rod lens length are selected. 4. The information reproducing device according to claim 1, wherein a gradient index rod lens array is used as the lens array, and a field stop is inserted in the middle portion of the rod of the rod lens. 5. A plurality of information tracks in which information is arranged in one dimension are arranged in a plurality of rows in the length direction and in a direction orthogonal to the length direction, and the information is arranged in the length direction of the information tracks. A card-shaped record carrier that is read by a one-dimensional lens array corresponding to an area of an information track, wherein the pitch in the longitudinal direction of the information track corresponds to the pitch of the lens array, and the length of the information track is An information recording carrier characterized in that the pitch is smaller than the pitch of an array. 6. The information recording carrier according to claim 5, wherein dummy data is recorded in areas satisfying the pitch of the lens array at both ends of the information track.