JP2015135711A - Optical information reproducing apparatus and optical information reproducing method - Google Patents

Abstract

An optical information reproducing apparatus capable of improving the information reproducing speed is provided.
An optical information generation apparatus 10 irradiates a reference light to generate a reproduction light including header information, and divides the generated reproduction light into a plurality of pieces so as to include the header information, respectively. A light east dividing section, a photographing section for photographing each of the divided reproduction lights, and a control section for processing header information of the photographed reproduction lights.
[Selection] Figure 1

Description

  The present invention relates to an optical information reproducing apparatus and an optical information reproducing method for reproducing an information signal by irradiating an optical information recording medium with reference light.

  As a background art, there is a technique disclosed in Patent Document 1. Patent Document 1 describes an information reproducing apparatus that reproduces information from a hologram recording medium in which an interference pattern is recorded as page data.

JP 2012-138148 A

  As a computer information storage device, a next-generation holographic memory type storage device is required to increase the speed in order to instantaneously read and retrieve a large amount of information.

  In Patent Document 1, one spatial light modulator and one photodetector are arranged adjacent to the polarization beam splitter.

  However, in the information reproducing apparatus described in Patent Document 1, the upper limit of the information reproducing speed is determined by the frame rate of the image sensor that detects a two-dimensional image (the number of images that can be captured per second). In order to increase the current information reproduction speed, the imaging system must have a higher resolution and a higher frame rate. However, as described above, there is a limit in the current image sensor, and the information reproduction speed cannot be greatly improved with the configuration as in Patent Document 1 described above.

  In order to solve the above problems, an object of the present invention is to provide an optical information reproducing apparatus capable of improving the information reproducing speed.

  The above object can be achieved, for example, by the invention described in the claims. Specifically, an optical information reproducing apparatus that reproduces information by irradiating a reference light to an optical information recording medium, the header information corresponding to the information by irradiating the optical information recording medium with the reference light The reproduction light generation unit that generates the reproduction light including the beam, the light beam division unit that divides the reproduction light generated by the reproduction light generation unit into a plurality of pieces so as to include the header information, and the division unit. An optical information reproducing apparatus comprising: an imaging unit that captures each of the reproduction lights; and a control unit that processes header information of the reproduction light imaged by the imaging unit.

  According to the present invention, a suitable optical information reproducing apparatus and optical information reproducing method can be provided.

It is a figure which shows the structural example of the pick-up optical system by this invention. It is a figure which shows the example of whole structure (block structure) of the information reproduction apparatus by this invention. It is an example of the recording data pattern of the medium used for this invention. It is a figure which shows the mode of the light beam splitting by the light beam splitting part by this invention. It is an example of the reproduction | regeneration image received on the image pick-up element in this invention. It is a figure which shows the mode of the optical path of the light beam of the reproduction | regeneration light in this invention. It is a figure which shows the specific structure of the light beam splitting part by this invention, and image pick-up element arrangement | positioning at the time of using a prism as a light beam splitting part. It is a figure which shows the relationship of the angle of the entrance plane of the light beam splitting part by this invention, a reflective surface, and an output surface at the time of using a prism as a light beam splitting part. It is a figure which shows the specific structure of the light beam splitting part by this invention, and image pick-up element arrangement | positioning at the time of using a reflective mirror as a light beam splitting part. It is a figure which shows the example of the transmittance | permeability / reflectance at the time of providing a semi-reflective area | region in the light beam splitting part by this invention when a prism is used as a light beam splitting part. It is a figure which shows the structure of the signal processing circuit which decompress | restores data from an image by this invention. It is a figure which shows the procedure which reads the address information from the reproduced image by this invention. FIG. 6 is a diagram illustrating a procedure for determining an effective address value according to the present invention. It is a figure which shows the decoding procedure of digital data by this invention. It is a figure which shows the decoding procedure of digital data by this invention. It is a figure which shows the decoding procedure of digital data by this invention. It is a figure which shows the example of the process timing from an imaging to a decoding process by this invention. It is a figure which shows the structure of the signal processing circuit which decompress | restores data from an image by this invention. FIG. It is a figure which shows the synthetic | combination method of the imaged image by this invention. It is a figure which shows the structure of the signal processing circuit which decompress | restores data from an image by this invention. It is a figure which shows the structure of the signal processing circuit which decompress | restores data from an image by this invention. It is an example of the recording data pattern at the time of 4 division | segmentation using the cross-shaped header by this invention. It is a structural example of the imaging optical system at the time of 4 division | segmentation using the cross-shaped header by this invention. It is a figure which shows the positional relationship of the pattern on a reproduced image, and arrangement | positioning of a division | segmentation boundary in the imaging optical system at the time of 4 division | segmentation using a cross-shaped header by this invention.

    Embodiments of the optical information reproducing apparatus and optical information reproducing method of the present invention will be described below.

(Purpose of configuration)
The performance of a typical CMOS camera device as a high-speed imaging device depends on the wafer process, but generally, the smaller the number of pixels in charge per horizontal / vertical signal line for the same pixel size, The frame rate can be increased. In addition, the wider the pixel pitch (pixel pixel interval), the thicker the horizontal / vertical signal lines, the lower the wiring resistance, the parallelization of multiple lines, and the addition of high speed buffers in the pixel circuit. The frame rate can be increased. As an example, a CMOS camera element with a vertical and horizontal 2000 pixel angle (4 megapixels) and a pixel pitch of 10 μm is 1500 frames / second, and a CMOS camera element with a vertical and horizontal 1000 pixel angle (1 megapixel) and a pixel pitch of about 30 μm is 15000 frames / second. About seconds are possible. Here, the frame rate is improved (15000 frames / 1500 frames = 10 times) more than the ratio of the total number of pixels (4 megapixels / 1 megapixel = 4 times) because the pixel pitch can be widened. This is the effect of the above speeding up.

Therefore, by adopting an optical system and apparatus configuration utilizing these effects, an optical information reproducing apparatus capable of performing an imaging process at a higher resolution and a higher frame rate by using an imaging element manufactured by the current process technology. The configuration.
(Configuration example of optical information reproducing device)
Hereinafter, an embodiment of the present invention will be described with reference to FIGS.

(Example of overall device configuration)
First, the overall configuration (block configuration) of the optical information reproducing apparatus according to the present invention will be described with reference to FIG.

  The optical information reproducing device 10 is connected to an external control device 91 via an input / output control circuit 90. The optical information reproducing apparatus 10 receives an operation command signal from the external control device 91 by the input / output control circuit 90. At the time of reproduction, the optical information reproduction apparatus 10 transmits the reproduced information signal to the external control apparatus 91 by the input / output control circuit 90. When recording, the input / output control circuit 90 receives the information signal to be recorded from the external control device 91.

  The optical information reproducing apparatus 10 includes a pickup 11, a cure optical system 13, a disk rotation angle detection optical system 14, and a spindle motor 215, and the disk 214 can be rotated by the spindle motor 215.

  The pickup 11 serves to read out digital information from the recording medium using holography by emitting and irradiating the reference light and signal light onto the disk 214. When recording on the disk 214, the information signal is sent to the spatial light modulator in the pickup 11 by the controller 89 via the signal generation circuit 86, and the signal light is modulated by the spatial light modulator. The irradiation time of the reference light and the signal light irradiated on the disk 214 is controlled by the controller 89 via the shutter control circuit 87.

  When reproducing the information recorded on the disk 214, the reproduction light reproduced by irradiating the laser light with the reference light at a predetermined position and angle is detected by an image pickup device (to be described later) in the pickup 11, and a signal processing circuit. The signal is processed by 85 to reproduce information.

  The cure optical system 13 is used at the time of recording, and plays a role of generating a light beam used for pre-cure and post-cure of the disk 214. Precure is a pre-process for irradiating a predetermined light beam in advance before irradiating the reference light and signal light to the desired position when recording information at a desired position in the disk 214. Post-cure is a post-process for irradiating a predetermined light beam after recording information at a desired position in the disk 214 so that additional recording is impossible. The disk rotation angle detection optical system 14 is used to detect the rotation angle of the disk 214. When the disk 214 is adjusted to a predetermined rotation angle, a signal corresponding to the rotation angle is detected by the disk rotation angle detection optical system 14, and the controller 89 uses the detected signal via the disk rotation motor control circuit 88. Thus, the rotation angle of the disk 214 can be controlled.

  A predetermined light source driving current is supplied from the light source driving circuit 82 to the light sources in the pickup optical system 11, the cure optical system 13, and the disk rotation angle detection optical system 14, and each light source emits a light beam with a predetermined amount of light. can do.

  The pickup optical system 11 and the disc cure optical system 13 are provided with a mechanism capable of sliding the position in the radial direction of the disc 214, and the position is controlled via the access control circuit 81.

  By the way, in the reproduction and recording using the principle of angle multiplexing of holography, the tolerance for the deviation of the reference beam angle tends to be extremely small.

  Therefore, a mechanism for detecting the deviation amount of the reference beam angle is provided in the pickup 11, a servo control signal is generated by the servo signal generation circuit 83, and the deviation amount is corrected via the servo control circuit 84. It is necessary to provide a servo mechanism for this in the optical information reproducing apparatus 10.

  Further, the pickup 11, the cure optical system 13, and the disk rotation angle detection optical system 14 may be simplified by combining several optical system configurations or all optical system configurations.

  In addition, the access control circuit 81, the light source drive circuit 82, the servo signal generation circuit 83, the servo control circuit 84, the signal processing circuit 85, the signal generation circuit 86, the shutter control circuit 87, the disk rotation motor control circuit 88, and the controller 89 are several. Such a circuit or all the circuits may be combined into one and simplified. Together, these will be collectively referred to as a control system in the following description and will be referred to as a control system 224 in FIG.

(Pickup configuration example)
Next, the detailed configuration of the pickup 11 will be described with reference to FIG. The disk 214, the spindle motor 215, and the control system 224 are the same as those in FIG. 2, but will be described again in the drawing and in the following description to clarify the positional relationship and control.

  Laser light 201 output from the laser light source 200 is divided into reference light 203 and signal light 204 by a beam splitter 202.

  The signal light 204 is reflected by the reflecting mirror 205, passes through the shutter 206, the beam expander 207, the phase mask 208, and the relay lens set 209, and is irradiated to the spatial light modulator 211 by the polarization beam splitter 210. The spatial light modulator 211 is a combination of a polarizing plate, a drive circuit chip, and a liquid crystal substance. The spatial light modulator 211 modulates (rotates) the polarization direction of light two-dimensionally and reflects it according to an input pattern signal. To do. The light reflected by the spatial light modulator 211 passes through the polarization beam splitter 210 and the relay lens 212 and is irradiated onto the disk 214 by the objective lens 213. The disk 214 is mounted on a spindle motor 215, and the irradiation position on the disk can be changed by rotation.

  On the other hand, the reference beam 203 is sequentially reflected by the reflecting mirror 220, the first galvanometer mirror 221, and the second galvanometer mirror 222, and is irradiated onto the disc 214 so as to cross the irradiation position of the signal light, and passes through the disc 214. Thus, the light is reflected by the third galvanometer mirror 223 and irradiated onto the disk 214 at substantially the same angle as the forward path. Each galvanometer mirror is a movable mirror configured such that the angle can be accurately controlled by the control system 224.

  The reference light 203 reflected by the galvanometer mirror 223 and incident on the disk 214 is diffracted by the hologram recorded on the disk 214 to generate reproduction light. The reproduction light passes through the objective lens 213 and the relay lens 212, is reflected by the polarization beam splitter 210, forms a reproduction image at the first image plane position 225, and enters the imaging optical system 230.

  The reproduction light incident on the imaging optical system 230 passes through the imaging system relay lens 231, and is split into transmitted light 234 and reflected light 235 by the light beam splitting unit 232 at the split boundary 233. The transmitted light 234 is received by the first image sensor 236, and the reflected light 235 is received by the second image sensor 237. FIG. 1 shows a configuration using a prism as an example of a light beam splitting unit 232 described later. In addition, the lens group of the imaging system relay lens 231 enlarges the image on the exit side with respect to the incident reproduced image by making the focal length of the exit side lens larger than the focal length of the entrance side lens ( Magnifying optical system). In this configuration, the focal length of the exit side lens is doubled that of the entrance side lens. When enlargement is unnecessary, the focal lengths of the exit side lens and the entrance side lens may be the same. This relay lens system is also called a 4F optical system. By inserting this relay lens system, it is possible to secure the optical path length before the image pickup element necessary for splitting the luminous flux. By inserting this relay lens system, the optical path length from the polarization beam splitter 210 becomes longer than the spatial light modulator side by 4 times or more of the beam diameter on the image pickup device side.

The first image pickup device 236 and the second image pickup device 237 are synchronously controlled by the control system 224. The reproduction image received at the same timing is synchronized with the exposure by the synchronization trigger signal 238 generated by the control system 224. 239a and 239b are output respectively. The output image data is subjected to signal processing in the control system 224,
By decoding, the digital data recorded on the disk 214 is restored.

  When data is recorded on the disk 214 in the same apparatus, the shutter 206 is opened when recording, and when the data is reproduced from the disk 214, the shutter 206 is closed and the presence / absence of signal light supply is switched.

  Note that the arrangement of the spatial light modulator 211 and the imaging optical system 230 with respect to the polarization beam splitter 210 can be changed according to the polarization direction.

(Relationship between recording pattern and imaging optical system)
Next, the relationship between the recording pattern recorded on the medium and the imaging optical system will be described with reference to FIGS.

(Recording pattern)
First, a recording pattern recorded on the disk 214 will be described with reference to FIG. FIG. 3 is an example of a recording data pattern 100 given to the spatial light modulator 211 when recording. The recording data is given to the above-described spatial light modulator 211 and irradiated onto the disk 214 together with the reference light, thereby causing light interference and recording on the disk 214.

  As shown in FIG. 3A, in the recording data pattern 100, a band-shaped header region 101 is arranged in the center through the top and bottom of a circular whole light beam, and recording is performed in the remaining region other than the header region 101. A data area 102 in which digital information to be encoded is two-dimensionally arranged is arranged. The header area 101 includes address information, clock information, and sync information, and information necessary for reproducing the data recorded in the data area 102 is recorded.

  FIG. 3B is an enlarged view of the upper part of FIG. More specifically, the band-shaped header region 101 has a three-column configuration, in which a clock pattern 103 is arranged in the center column and an address pattern 104 is arranged in the left and right columns. The clock pattern 103 is a periodic pattern that gives a reference position of an image when reading the address pattern, and the address pattern 104 is a pattern in which address information such as page number information and position information of recording data is encoded. ing. The left and right address patterns 104 in two columns contain the same information. A sync mark 105 is arranged on the clock pattern 103. The sync mark 105 is a position reference mark for dividing the header area 101 into a plurality of sections and synchronizing the start and end points of the data in each section, and allows each data to be read out on the divided sections. Thus, the reliability can be improved, and it can also be used as a position reference mark for image alignment when the header area 101 is photographed by a plurality of image sensors.

(Basic configuration of imaging optical system)
Next, a detailed structure of the imaging optical system 230 will be described with reference to FIGS.

  As described above, in the imaging optical system 230, the light beam splitting unit 232 splits the light beam into the first image sensor and the second image sensor.

  Specifically, the light beam splitting unit 232 may be a prism or a reflecting mirror, and may have a plurality of configurations including the direction of emission of the split light beam. Regardless of the configuration, the position of the reflection boundary, which is the boundary line of the light beam splitting unit 232, is adjusted so that it overlaps the band-shaped header area 101 of the recording data pattern applied to the spatial light modulator 211 during reproduction. Arrange. This state will be described first with reference to FIGS.

  FIG. 4 shows how the light beam splitting unit 232 splits the light beam. The reproduced hologram pre-division reproduction image 240 is the same pattern as the recording data pattern 101 except for deterioration. As shown in FIG. 4A, the division boundary 233 of the light beam dividing unit 232 is adjusted by adjusting the position of the light beam dividing unit 232 so as to overlap the band-shaped header region 101 on the reproduced image of the recording data pattern 100. . As a result, the reproduced image is divided into a left half and a right half as shown in FIG. The light beam splitting unit 232 uses a prism, but even when a reflecting mirror is used, the reflected light beam is reversed left and right as shown in FIG. 5 by mirror image reversal. Specifically, the reproduced image received by the first image sensor 236 remains as shown in FIG. 5 (b1), whereas the reproduced image received by the second image sensor 237 is as shown in FIG. 5 (b2). Reverse horizontally. Therefore, when the image data 239a and 239b are signal-processed and decoded in the control system 224, processing is performed corresponding to the reversal of the reproduced image.

  Returning to FIG. 4 (a), the left and right images to be divided do not change in a stepwise manner with respect to the division boundary 233, but only by the spread angle of the light beam of the reproduction light. , It will be a gradual (gradual) change. Specifically, in FIG. 4A, when the post-split light efficiency 251 is plotted against the position 250, the left half light efficiency 252 (dotted line) starts to decrease slightly to the left of the split boundary 233, and the split boundary It decreases linearly to the right and becomes zero. Conversely, the right half light efficiency 253 (solid line) starts to rise slightly to the left of the dividing boundary 233, increases linearly to the right of the dividing boundary, and reaches 100%. The reason for this will be described with reference to FIG.

  FIG. 6 shows an optical path when the light beam of the reproduction light having a spread angle is divided using a reflecting mirror. The central light beam separated at the division boundary 233 is divided in half by the reflection surface 254. Since the amount of light reaching the first image sensor 236 and the second image sensor 237 changes according to the spread angle and position of the light beam, the light efficiency changes gently. A typical value of the spread angle is 0.5 degrees to 3 degrees.

  The spread angle of the light beam is determined by the setting of the hologram optical system. If the setting of the hologram optical system is not supported, when the position of the division boundary 233 deviates from the center on the band-shaped header area 101, the pattern of the header area 101 divided right and left as shown in FIG. Division is also unbalanced. When the division of the header area 101 becomes unbalanced, the clock mark 103 and the sync mark 105 are not included in one header area 101, and the address information cannot be reproduced. A countermeasure structure for this will be described later.

(Multiple configuration examples of the beam splitting unit)
Various specific configurations of the arrangement of the light beam splitting unit and the image sensor are possible in addition to the configuration of FIG. Hereinafter, an example in which a prism is used as the light beam dividing unit and a case in which a reflecting mirror is used will be described with reference to FIGS.

  First, FIG. 7 to FIG. 8 show configuration examples in the case where a prism is used as the light beam splitting unit.

  When the prism is used, it is large, as shown in FIG. 7 (a), in which the light beams are reflected in a direction in which the light beams do not cross each other, and the reflected light beams are reflected as shown in FIG. 7 (b). There are two types, a configuration in which the remaining half of the light beam is internally reflected in the direction of crossing within the prism.

  At this time, as shown in FIG. 8, the angle of the reflecting surface 261 with respect to the incident surface 260 is defined as a reflecting surface angle 262 (θ). In the configuration in which the light beams are reflected in directions that do not cross each other (FIG. 8A), θ is slightly shallower than 45 degrees (θ <45 degrees: closer to the transmitted light side (θ = 42 to 44 degrees)). . When crossing inside the prism (FIG. 8B), it is slightly deeper than 45 degrees (θ> 45 degrees: closer to incident light (θ = 46 to 70 degrees)). The reason for this is to prevent irregular reflection inside the prism due to the angular deviation of the optical component, so that there is a margin of about 1 degree in angle. If θ is too large (θ ≧ 70 degrees), a wide reflecting surface is required and a long optical path length is required. Therefore, θ should be less than 70 degrees.

  When the angle of the exit surface 263 with respect to the entrance surface 260 of the prism is the exit surface angle 264, the exit surface angle 264 is 2θ in accordance with the above. As a result, aberration generation and diffuse reflection of the beam in the prism can be prevented, and the reflected light image can be correctly collected on the camera.

(Configuration with semi-reflective area)
As described above, when the position of the division boundary 233 is shifted from the center on the strip-shaped header area 101, the division of the pattern of the header area 101 divided into left and right is also unbalanced as shown in FIG. 4B. . In order to detect an address with high reliability, it is desirable that the clock pattern 103 and the sync mark 105 in the center of the header area are included on both of the divided image receiving patterns. As a countermeasure against this, a semi-reflective region 270 can be provided near the reflection boundary 233 of the reflection surface 261 as shown in FIG. The semi-reflective region is a semi-reflective mirror surface that reflects light about half (near 50%: 30 to 70%) and transmits about half (near 50%: about 70 to 30%). By making the semi-reflective region a partly semi-reflective region in the vicinity of the boundary, as shown in FIG. 10 (a), the semi-reflective region can be obtained in the divided light efficiency 251 on the header region near the reflective boundary. By providing a small step in the middle of the width 271, the change in reflectance can be made substantially gentle. As a result, as shown in FIG. 10B, the imbalance in light efficiency is alleviated, and the signal in the header region 101 can be more reliably divided into both the first image sensor 236 and the second image sensor 237. As a result, the relative positional deviation margin between the light beam of the reproduction light and the light beam splitting unit 232 is widened, and the header information can be read more reliably.

  Even when a reflecting mirror is used, as shown in FIG. 9A, half of the light beam is reflected in a direction in which the light beams do not cross each other, and the reflected light beam remains as shown in FIG. 9B. There are two types, a configuration in which half the luminous flux intersects the optical path.

  When a reflecting mirror is used, there is no problem of internal reflection inside the component like a prism, and astigmatism does not occur due to a deviation in the mounting angle of the component like a prism, so the angle (θ) of the reflecting surface is free. The emission direction can be adjusted over a wide angle range. It is also possible to simply set θ = 45 degrees.

  When the divided light beam crosses the transmitted light beam (arrangement), it is not necessary to sharpen the mirror end of the reflecting mirror (it may be a normal right angle), and the cost is low.

  When the light beams are reflected in directions that do not cross each other, as shown in FIG. 9A, one side (mirror end) of the reflecting mirror that is the reflecting boundary is processed at an acute angle (<θ), and near the boundary of the transmitted light Prevents hiding by the thickness of the reflector. For this reason, it is easy to create a crossing configuration when a reflecting mirror is used. However, particularly when θ = 45 degrees (θ = 30 to 60 degrees) and a structure that does not cross (cross), the structure is set immediately after the reflecting mirror. Since the second imaging element can be arranged and the optical path length can be shortened, there is an advantage that the entire imaging optical system can be made compact.

  As described above, in both cases of using a prism and a reflector, the reflected split light (reflected light) is reflected, and the reflected light is detected. The image captured by the second image sensor 237 is an image that is reversed left and right. If the image pickup system relay lens 231 is an enlarged optical system, the reproduced image becomes an enlarged image. Therefore, the pixel pitch is widened, and the width of horizontal and vertical signal lines arranged vertically and horizontally in the pixel region can be increased. it can. For this reason, since the wiring resistance of the signal line is reduced, the number of pixels per scanning line is halved, and the processing in the first image sensor 236 and the second image sensor 237 is accelerated, which is more preferable.

  The divided reproduced images include a header region in both images in FIGS. 5B1 and 5B2. Address information may be read from the header area 101 photographed by either the first image sensor 236 or the second image sensor 237.

  In this configuration, the header area 101 uses a pattern having a margin in S / N, so that the header can be read correctly even if it is divided and the amount of light is reduced. In addition, the header area 101 is divided so that the left half and the right half include the same data, so that even if the data pattern 100 is divided into a plurality of image pickup devices and received, the data pattern 100 is received by each image pickup device. Can read the header information necessary to play In addition, since one data pattern 100 is photographed by two image sensors, the number of pixels per scanning line can be halved. Therefore, with a CMOS camera or a CCD camera of the same processing process, the frame rate can be approximately doubled. The reproduction speed of the optical information reproducing apparatus can be doubled by adding one image sensor.

  Note that the exposure time and pause period can be shortened to nearly zero by using a pulse laser together. With this configuration, even when data is read from two image sensors at the same pixel transfer rate, data is reproduced using only one image sensor. Compared with the case, the information reading speed can be improved almost twice.

  In addition, in this configuration, an optical path having a predetermined length is secured by using a relay lens in the previous stage of splitting the light beam, so that a margin for arrangement can be secured even if the light beam splitting unit is inserted. .

  In addition, by using a magnifying optical system, if the CMOS camera or CCD camera has the same processing process, the width of the horizontal and vertical signal lines arranged vertically and horizontally in the pixel area is increased by increasing the pixel pitch. Since the wiring resistance of the signal line is reduced, the number of pixels per scanning line is halved, so that the frame rate can be further improved. When the frame rate is improved, the processing speed of each image sensor is increased, and the apparatus reproduction speed can be increased more than the number of image sensors.

  When a prism is used as the beam splitting unit, the optical path length is changed by inserting the prism, but the beam spread angle of the reproduction beam in the hologram optical system is small (<2 to 3 degrees), and the beam diameter is about 15 mm and the thickness is 15 mm. Even when a glass prism is inserted in the optical path, the aberration due to the prism insertion is about 0.001 λrms, and image degradation due to the prism insertion can be ignored. In addition, since the optical path length is shorter by the refractive index than in the air, the focal length of the relay lens can be set shorter, and there is an advantage that the entire imaging optical system 230 can be made compact accordingly. Furthermore, since the reflecting surface is embedded in the prism glass, the reflecting boundary can be protected with a mechanically robust structure, and it is resistant to aging.

(Signal processing unit configuration)
Next, the configuration of the signal processing circuit and the specific processing flow until the original digital data is restored from the received data of the two image sensors will be described with reference to FIGS.

(2 system independent signal processing)
First, FIG. 11 to FIG. 17 show a configuration in the case where image reception data of two image sensors is separately processed.

  11 shows the image data 239a and 239b imaged by the first image sensor 236 and the second image sensor 237 in FIG. 1, and is signal-processed and decoded by the signal processing circuit 85 in the control system 224. The configuration of the processing circuit until output to the input / output control circuit 90 is shown. The components from the first image sensor 236 and the second image sensor 237 to the controller 89 are included in the signal processing circuit 85. The configuration will be described below in order.

  First, the image data 239a and 239b captured by the first image sensor 236 and the second image sensor 237 are first stored in the frame buffers 370a and 370b, respectively. Each frame buffer receives each image data and outputs buffered images 371a and 371b in synchronization with each other. The data area detectors 394a and 394b receive the buffered images 371a and 371b, respectively, detect the entire data area including the header area, extract the image of the area, and output the data area images 395a and 395b, respectively. The header detectors 372a and 372b receive each data area image, detect the position of the header area 101 in the image, and output header address values 373a and 373b read from the header area 101. The address comparison / selection device 375 receives each header address value and outputs an effective address value 376 and an error flag signal 377. The image inverter 378 receives the data area image 395b, reverses the image horizontally, and outputs an inverted image 379. The image corrector 382a receives the data area image 395a from the frame buffer 370a, and the image corrector 382b receives the inverted image 379 from the image inverter 378. Each of the image distortions and the brightness is a reference mark included in the data area 102. Are used to output corrected images 383a and 383b. The two-dimensional decoders 384a and 384b decode the two-dimensional codes for the corrected images 383a and 383b, thereby converting them into digital bit data, and output the decoded data 385a and 385b. The deinterleavers 386a and 386b receive the decoded data 385a and 385b, and output the deinterleaved data 387a and 387b. Error correctors 388a and 388b receive post-interleave data 387a and 387b, and output post-error correction data 389a and 389b. Descramblers 390a and 390b receive error-corrected data 389a and 389b, and output restored digital data 391a391b. The controller 89 receives the restored digital data 391a and 391b, the effective address value 376, and the error flag signal 377, confirms that the read request page number matches the page number included in the address information, and correctly reads the data of both image sensors. The output is output as a normal read notification signal 396 to notify the input / output control circuit 90. The input / output control circuit 90 receives the normal read notification signal 396 and the restored digital data 391a391b, and transmits / receives data to / from the external control device 91.

  In this configuration, the image data (right column) imaged by the first image sensor 236 and the image data (left column) imaged by the second image sensor 237 are separately decoded, via the input / output control circuit 90. The data is output to the external control device 91. In this configuration, since the processing of image data of each image sensor can be made independent, the signal processing circuit becomes smaller and the load on the signal processing circuit is reduced as compared with the case where processing is performed by one signal processing circuit. There is an advantage that the processing is speeded up.

Next, the outline of the process using the above configuration will be described in detail with reference to the flowcharts of FIGS.
FIG. 12 is a flowchart showing a procedure for reading address information included in the address pattern 104 of the header area 101 by each of the two image sensors. The procedure is common to the two image sensors.

  When the processing start is started, first, in step S110, image data photographed by the first image sensor 236 and the second image sensor 237 is acquired from the frame buffers 370a and 370b. Next, in step S111, the header detectors 372a and 372b detect the coordinate values of the header area 101 from the images acquired by the frame buffers 370a and 370b. Next, in step S112, it is determined whether the coordinates of the acquired header area 101 are correct. The reference whether the coordinate value of the header area 101 is correct is determined when the system is designed. If the acquired coordinate value of the header area 101 is not correct (No), the error flag is stored in a storage unit (not shown) provided in the controller 89 in step S118, and the process is terminated. If the coordinate value of the header area 101 is correct (Yes), the clock pattern 103 included in the header area 101 is searched in the next step S113. When the clock pattern 103 is not searched by the clock pattern detection determination 314 (No), the error flag is stored in a storage unit (not shown) provided in the controller 89 in step S118, and the process is terminated. If a search is made (Yes), the process proceeds to step S115. In step S115, the address pattern 104 included in the header area 101 is read. In the read address pattern 104, a verification code (checksum, parity, CRC code, etc.) is added to the address value. In step S116, a checksum check is performed on the address information of the address pattern 104 searched using the verification code, error correction is performed, and the process proceeds to step S117. In step S117, the address checksum check result and error corrected address information are sent to the address comparison / selection device 375, and the process of reading the address information is terminated.

  The above process is performed on the semicircular imaging data acquired by the first imaging element 236 and the semicircular imaging data acquired by the second imaging element 237.

  Next, the address comparison / selector 375 determines the two pieces of address information obtained by the above processing. This determination process is also performed in the signal processing circuit 85.

  FIG. 13 shows a procedure for determining a valid address value from the two pieces of address information obtained by the above processing.

  First, when the process is started, it is determined in step S130 whether the address pattern 104 can be read correctly from the image data 239a acquired by the first image sensor 236 from the address information and the inspection result obtained by the procedure of FIG. If it cannot be read correctly (No), the process proceeds to step S131 in the right column. In step S131, it is determined whether the address pattern 104 can be read correctly from the image data 239b photographed by the second image sensor 237. If it cannot be read correctly (No), the process proceeds to step S134, the error flag is stored in a storage unit (not shown) provided in the controller 89, and the process ends. If it can be read correctly (Yes), the process proceeds to step S136, and the address information included in the image data 239b acquired by the second image sensor 237 is stored as a valid address value in a memory (not shown) provided in the input / output control circuit 90. To finish the process.

  If it can be read correctly in Step S130 (Yes), the process proceeds to Step S132 in the left column, and it is determined whether the address information included in the image data 239b acquired by the second image sensor 237 can be read. If it cannot be read correctly (No), the address information included in the image data 239a previously acquired by the first image sensor 236 can be read correctly, so the process proceeds to step S135 and is included in the image data 239a acquired by the first image sensor 236. The stored address information is stored in an effective address value of a memory (not shown) included in the input / output circuit 90, and the process is terminated. If it can be read correctly in step S132 (Yes), both address information can be read correctly, so the process proceeds to step S133, and the address information included in the image data 239a acquired by the first image sensor 236 and acquired by the second image sensor 237. The address information included in the image data 239b is compared to determine whether the address information matches. If they do not match (No), the error flag is stored in the storage unit (not shown) of the controller 89 in the error flag storage 334, and the process is terminated. If they match (Yes), the process proceeds to step S135, and the address information included in the image data 239a acquired by the first image sensor 236 is converted to an effective address value of a memory (not shown) provided in the input / output circuit 90. Store and finish the process.

  In this process, the address pattern 104 in which the verification code is added to the address information is photographed by the two image pickup devices 236 and 237, and the address is read by the verification code of the address pattern 104 included in each of the image data 239a and 239b. Validate information. For this reason, by adopting the address information verified by the address pattern 104 included in one of the image data as valid address information, the number of cases where the address information can be read increases. In addition, since the address information included in the image data 239a acquired by the first image sensor 236 is compared with the address information included in the image data 239b acquired by the second image sensor 237, one of the image sensors is Even when an incorrect value of address information is read, it can be determined as an error, so that the reliability of address reading in the header area 101 can be improved.

  14 to 16 show a processing procedure from the data area 102 of the recording data pattern 100 to decoding the recorded digital data.

  First, a procedure for decoding digital data from image data 239a acquired by the first image sensor 236 will be described with reference to FIG.

  When the process is started, in step S200, coordinate range information of the image data 239a included in a predetermined range is obtained. The coordinate range of the data area 102 is a two-dimensional coordinate and is divided into a plurality of rectangular areas. Reference marks are added to the divided rectangular areas every predetermined number. The processing in step S200 is performed by the data area detector 394a, and the obtained coordinate range information is sent to the image corrector 382a. Next, in step S202, the position coordinates of the reference marker within the coordinate range obtained by the data area detector 394a are obtained. There are a plurality of reference markers in the data area 102. Next, in step S203, re-sampling is performed using the reference marker detected earlier to correct image displacement and image distortion. Next, a luminance level serving as a reference for correction of brightness (luminance) is obtained from the pixel at the position of the obtained reference marker. Next, in step S204, the brightness (luminance) of the image is corrected based on the detected luminance level of the marker. At the same time, equalization processing is performed. The processes in steps S202, S203, and S204 are performed by the image corrector 382a, and the obtained image is sent to the two-dimensional decoder 384a. Next, in step S205, the image obtained from the image corrector 382a is two-dimensionally decoded by the two-dimensional decoder 384a, and the digital data is extracted by decoding the code modulation from the luminance pattern of each image. And sent to the deinterleaver 386a. In step S206, deinterleaving processing is performed. In the digital data obtained by the two-dimensional decoder 384a, bit information is mixed (or replaced) with each part data in the data area by the interleaving process at the time of recording in order to increase error resistance. Return to the original. As a result, even if a part of the reproduced image is damaged due to a physical factor, the damaged data can be dispersed and the correction capability can be improved. Then, the data restored by the interleave canceller 386a is sent to the error corrector 388a.

  Next, in the error correction processing in step S207, the data sent from the deinterleaver 386a is compared with the content of the error correction code and the main data by the error corrector 388a, and the data is not correctly read (bit). Correct the process. In step S208, it is determined whether the error correction process has been correctly corrected. If there is a lot of noise and correction processing cannot be performed (No), the process proceeds to step 209. If correct correction processing can be performed (Yes), the corrected data is sent to the descrambler 390a, and the process proceeds to step S210. In step S209, the error flag is stored in a storage unit (not shown) provided in the controller 89, and the process ends. In step S210, the data corrected by the error corrector 388a is descrambled by the scrambler 390a to obtain finally restored digital data, and the process ends.

  The above is the procedure for restoring the image data from the first image sensor 236.

  In the procedure for restoring the image data from the second image sensor 237, since the image obtained on the image sensor first is mirror-inverted, an image inversion process is added. As a specific method, as shown in FIG. 15, before and after the data area detection, in step S201, image inversion processing is performed using the image inverter 378. The subsequent processing is the same as in FIG. In FIG. 15, the image inversion process is performed after the data area detection process in step S200. However, the image inversion process may be performed before the data area detection process in step S200, or two-dimensional decoding process at the time of decoding instead of the image inversion process. Instead of this, the two-dimensional decoding process for the reverse image in step S211 may be performed. At this time, the image inverter 378 is omitted, and instead, the two-dimensional decoder 384b is provided with an inverted image corresponding function. The configuration of FIG. 16 is possible when a symmetrical reference marker pattern is used as the reference marker, and there is an advantage that many processes can be shared between the image of the first image sensor and the image of the second image sensor. is there.

  FIG. 17 shows the processing timing when this embodiment is used. FIG. 17A shows a case where a single image pickup device is used without using the main beam splitting, and FIG. 17B shows an image pickup device when processing is performed with two image pickup devices divided as in the present configuration. 6 is a timing chart of data output and image signal processing. In this figure, each signal and processing timing are shown with respect to time 400 on the horizontal axis. In general, the hologram recording / reproducing apparatus synchronizes the movement of the galvanometer mirror and the imaging timing of the imaging device. When the exposure synchronization trigger signal 401 is supplied, a pulse is generated at an exposure synchronization timing 402a that is a timing at which exposure is to be synchronized, and is supplied to the image sensor.

  As a comparison, first, in the case of a single image sensor, the hologram reproduction image is exposed on the image sensor at the exposure synchronization timing 402a, and a single image sensor output data signal 403 is output. Based on this data signal, signal processing as shown in FIGS. 11 to 16 is performed, and decoded data 404 is output. After completion of the decoded signal processing, exposure can be started at the next exposure synchronization timing 402b.

  Next, when two image sensors using this embodiment are used, the number of processed pixels per unit is halved. Therefore, as shown in FIG. 17B, images from each image sensor. The periods of the first image sensor output data signal 405 and the second image sensor output data signal 406, which are data, are each halved. In addition, since the first image sensor image decoded data 407 and the second image sensor image decoded data 408, which are subsequent decoded signal processes, can be processed in parallel in this configuration, compared to the case of FIG. The period is half, and the overall frame rate is increased to about twice.

(Two-system linkage signal processing)
Next, regarding the configuration when the error correction capability is increased by synthesizing the received data of the two image sensors in the middle of the signal processing into one composite data and processing the composite data. This will be described with reference to FIGS.

  First, with reference to FIG. 18, the overall configuration of the signal processing unit when image reception data of two image sensors is combined at the image stage will be described.

  The configurations of the frame buffers 370a and 370b, the data area detectors 394a and 394b, the address comparison selector 375, and the image inverter 378 are the same as those in FIG. The header detectors 372a and 372b output address position information 374a and 374b in addition to the header address values 373a and 373b.

  The left-right image combiner 380 receives the address position information 374a and 374b including the position coordinates of the sync mark, the data area image 395a output from the data area detector 394a and the inverted image 379 output from the image inverter 378. As shown in FIG. 19, the two images are aligned in the vertical direction and combined based on the position coordinates of the sync mark 105, and a combined image 381 is output. When the relative positional relationship between the two image sensors is mechanically fixed, coordinates for alignment can be stored in advance in a storage unit (not shown) of the control system 224. Or you can learn and update the coordinates. By storing in advance, the initialization operation can be speeded up. In addition, by updating the coordinates by learning, reliability can be maintained even if a change with time due to a temperature change or a mechanical position shift due to a change with time occurs.

  The image corrector 382 receives the combined image 381, corrects the distortion and brightness of the image with reference to a reference mark included in the image, and outputs a corrected image 383. The two-dimensional decoder 384 decodes the two-dimensional code, converts it into digital bit data, and outputs decoded data 385. The deinterleaver 386 receives the decoded data and outputs the deinterleaved data 387. The error corrector 388 receives the data after deinterleaving and outputs error corrected data 389. The descrambler 390 receives the error-corrected data and outputs restored digital data 391. The controller 89 receives the restored digital data 391a and 391b, the effective address value 376, and the error flag signal 377, and outputs a normal read notification signal 396. The input / output control circuit 90 receives the normal read notification signal 396 and the restored digital data 391 and transmits / receives data to / from the external control device 91.

  In this embodiment, data obtained from a plurality of images obtained from a plurality of image sensors can be combined in the state of an image to restore the entire original reproduced image, and therefore, an interleaving process was performed on the entire data area. Discs recorded with a recording pattern can be played back. When the reproduced image is locally damaged, it is diffused over a wider area by the interleaving process, and the error density can be reduced. Therefore, the apparatus can have a higher error correction capability.

  Next, with reference to FIG. 20, the entire signal processing unit in the case where the data from the two image sensors is combined after the two-dimensional decoding process is completed in the two-dimensional decoders 384 a and 384 b instead of the image state. The configuration will be described.

  The configurations of the frame buffers 370a and 370b, the data area detectors 394a and 394b, the header detectors 372a and 372b, the address comparison selector 375, the image inverter 378, the image correctors 382a and 382b, and the two-dimensional decoders 384a and 384b are as follows: This is the same as FIG. The two-dimensional decoders 384a and 384b decode the two-dimensional code, convert it into digital bit data, and output decoded data 385a and 385b. The data combiner 392 mixes the decoded data 385a and 385b on the data, combines them, and outputs the combined data 393. Specifically, since it is a combination on data, the two stream data may be mixed alternately in units of sectors, or the data may be mixed while rearranging according to the physical arrangement of recording patterns. The deinterleaver 386, the error corrector 388, and the descrambler 390 are the same as those in FIG. The descrambler 390 outputs the restored digital data 391 to the controller 89 and the input / output control circuit 90.

  In the configuration of this embodiment, data obtained from a plurality of images obtained from a plurality of image sensors is combined with decoded digital data to restore the information of the entire original reproduced image. Since the digital data after decoding is combined, the combining process is simple. The entire data area can be interleaved, and the error correction capability is the same as in the case of combining before correcting the image by the image corrector 382 as in the example of FIG. In this embodiment, since the combining process is performed after the decoding process by the two-dimensional decoders 384a and 384b, the data combining process is simplified, and the apparatus can be made at a lower cost.

  In addition to the present embodiment, it is also possible to combine left and right data at an arbitrary stage between the correction processing by the image correctors 382a and 382b and the deinterleaving processing by the interleave canceller 386. The effect in that case is also the same.

  Next, with reference to FIG. 21, an example of the overall configuration of another signal processing unit when image reception data of two image sensors is combined in an image state will be described.

Compared to FIG. 18, there is no address comparison / selection device 375. Instead, a header detector 372 is provided with the combined image 381 obtained by combining the left and right images as an input. Unlike the header detectors 372a and 372b, the header detector 372 reads all the address patterns included in the entire header area on the combined image, and when some of the address patterns are damaged. Performs more powerful error correction processing, performs address determination by majority decision, and outputs a valid address value 376 and an error flag signal 377. For this reason, the reliability of address detection (reading) can be further improved. Note that the reliability of the restored digital data in the data area can also realize a high error correction capability similar to the configuration of FIGS.
(Composition in 4 divisions using cross pattern)
Next, a configuration example in the case where a recording data pattern in the case where a cross-shaped header region 280 is provided as a header, as shown in FIG. In this case, the light beam can be further divided into four. When recording, a pattern as shown in FIG. 22 is applied to the spatial light modulator to record a hologram on the disk.

  FIG. 23 is a configuration example of the light beam splitting unit and the image sensor when the recording data pattern is used when the cross-shaped header pattern is used. In this configuration, it is possible to detect the light beam divided into four parts by dividing the light beam into four image pickup elements using three reflecting mirrors. Specifically, the pre-division reproduced image 240 that has entered the light beam incident area 281 is first divided into half of the upper half transmitted light and the lower half reflected light by the light beam dividing unit 232a. Subsequently, the upper half of the transmitted light is divided into the right half of the transmitted light and the left half of the reflected light by the light beam splitting unit 232b. The right half transmitted light is received by the first image sensor 236, and the left half reflected light is received by the second image sensor 237.

  The reflected light in the lower half is reflected upward, and is divided into the transmitted light in the left half and the reflected light in the right half by the light beam splitting unit 232c. The transmitted light in the left half is received by the third image sensor 282, and the reflected light in the right half is received by the fourth image sensor 283.

  FIG. 24 shows an arrangement relationship between the reproduced image of the recording pattern and the division boundaries 233a, 233b, and 233c on each light beam dividing section. The division boundaries 233a, 233b, and 233c received by each image sensor are arranged so as to overlap the header pattern.

  A recording data pattern is received by combining a cross-shaped header pattern and four image sensors. In the header area, as in the case of FIG. 3, address information including the same contents is arranged in each of the header patterns in the four directions of the cross so that the addresses can be detected even in the divided state.

  By doing in this way, the reliability of address information acquisition from the image received by the image sensor is improved. In addition, since the data of each image sensor is processed in parallel, signal processing up to decoding is accelerated. Since the data received by each image sensor is small, the length of the horizontal and vertical signal lines arranged vertically and horizontally in the pixel area is shortened, thereby reducing the wiring resistance of the signal lines and improving the frame rate. The information reproducing apparatus can be configured with a higher speed. Furthermore, since the data to be received is small, the size of the IC chip relating to image processing and transfer processing of each image sensor can be reduced, and the transfer processing can be speeded up. As a result, the overall data reproduction speed of the apparatus can be improved more than the speeding up of the process by the four parallel processes.

  The signal processing of this embodiment may be the same as that in the example (FIGS. 11 to 21) when the recording data pattern is divided into two.

  Specifically, in FIG. 23, the first image sensor 236 does not reflect and is therefore non-inverted, and the process of the flow of FIG. The three image sensors 282 are inverted to reflect and are processed by the flow of FIG. 15 or FIG. 16, and the fourth image sensor 283 is not reflected and are non-inverted to be processed by the flow of FIG. When a pattern that is symmetrical in the vertical and horizontal directions is used for the reference marker, the process is the same up to the two-dimensional decoding process in step S205 in FIG. There is an advantage that many processes can be shared.

  Also, the four received data obtained from the four image sensors are combined in the middle of signal processing into one combined data, and the interleave processing and error correction processing are performed on the combined data, so that the data on the entire image area Error correction processing can be performed on data. For this reason, compared with the case where individual data are separately subjected to interleave processing and error correction processing, it is possible to improve error correction capability against local image damage and optical noise, such as the first image plane position and the pre-division reproduced image. The entire light beam can be maintained in the same manner as when the image is received by one image sensor, and reliability can be ensured.

  In addition, the arrangement shown in FIG. 23 allows the first to fourth imaging elements to be spaced sufficiently apart, and even when the imaging element is mounted on the circuit board, a space for arranging the board can be secured. .

  In addition, this invention is not limited to an above-described Example, Various modifications are included. For example, the above-described embodiments have been described in detail for easy understanding of the present invention, and are not necessarily limited to those having all the configurations described. Further, a part of the configuration of one embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of one embodiment. Further, it is possible to add, delete, and replace other configurations for a part of the configuration of each embodiment.

  In addition, each of the above-described configurations may be configured such that some or all of them are configured by hardware, or are implemented by executing a program by a processor. Further, the control lines and information lines indicate what is considered necessary for the explanation, and not all the control lines and information lines on the product are necessarily shown. Actually, it may be considered that almost all the components are connected to each other.

DESCRIPTION OF SYMBOLS 10 Optical information reproducing | regenerating apparatus 11 Pickup 12 Reference light optical system for reproduction | regeneration 13 Cure optical system 14 Optical system for disc rotation angle detection 81 Access control circuit 82 Light source drive circuit 83 Servo signal generation circuit 84 Servo control circuit 85 Signal processing circuit 86 Signal generation Circuit 87 Shutter control circuit 88 Disk rotation motor control circuit 89 Controller 90 Input / output control circuit 91 External controller 100 Recording data pattern 101 Header area 102 Data area 103 Clock pattern 104 Address pattern 105 Sync mark 200 Laser light source 201 Laser light 202 Beam splitter 203 Reference Light 204 Signal Light 205 Reflector 206 Shutter 207 Beam Expander 208 Phase Mask 209 Relay Lens Set 210 Polarizing Beam Splitter 21 Spatial light modulator 212 Relay lens 213 Objective lens 214 Disk 215 Spindle motor 220 Reflector 221 First galvanometer 222 Second galvanometer 223 Third galvanometer 224 Control system 225 First image plane position 230 Imaging optical system 231 Imaging system relay lens 232 232a, 232b, 232c Beam splitting unit 233, 233a, 233b, 233c Split boundary 234 Transmitted light 235 Reflected light 236 First image sensor 237 Second image sensor 238 Synchronous trigger signal 239a, 239b Image data 240 Pre-division reproduced image 250 Position 251 Light efficiency after division 252 Left half light efficiency 253 Right half light efficiency 260 Incident surface 261 Reflecting surface 262 Reflecting surface angle 263 Exiting surface 264 Exiting surface angle 270 Semi-reflecting region 271 Semi-reflecting region width 280 Character-shaped header area 281 Light flux incident area 282 Third image sensor 283 Fourth image sensor 310 Image sensor image data acquisition 311 Header position detection 312 Header position detection determination 313 Clock pattern detection 314 Clock pattern detection determination 315 Address pattern read 316 Address checksum Inspection 317 Address value / inspection result storage 318 Error flag storage 330 First imaging element address value readable determination 331 Second imaging element address value readable determination 332 Second imaging element address value readable determination 333 First and second imaging element address value match Determination 334 Error flag storage 335 First image sensor effective address value storage 336 Second image sensor effective address value storage 350 Data area detection 351 Image inversion 352 Reference marker detection 353 Image distortion correction 354 Degree correction 355 Two-dimensional decoding process 356 Interleave cancellation 357 Error correction process 358 Error correction process determination 359 Error flag storage 360 Descramble 361 Reverse image two-dimensional decoding process 370a, 370b Frame buffer 371a, 371b Buffered image 372, 372a, 372b Header detector 373a, 373b Header address value 374a, 374b Address position information 375 Address comparison selector 376 Effective address value 377 Error flag signal 378 Image inverter 379 Inverted image 380 Left and right image combiner 381 Combined image 382, 382a, 382b Image corrector 383, 383a, 383b Corrected image 384, 384a, 384b Two-dimensional decoder 385, 385a, 385b Decoded data 386, 386a, 86b Deinterleaver 387, 387a, 387b Deinterleaved data 388, 388a, 388b Error corrector 389, 389a, 389b Data after error correction 390, 390a, 390b Descrambler 391, 391a, 391b Reconstructed digital data 392 Data combiner 393 Post-combination data 394a, 394b Data area detector 395a, 395b Data area image 396 Normal read notification signal 400 hours 401 Exposure synchronization trigger signal 402a, 402b Exposure synchronization timing 403 Single image sensor output data signal 404 Decoded data 405 First Image sensor output data signal 406 Second image sensor output data signal 407 First image sensor image decoded data 408 Second image sensor image decoded data

Claims (11)

An optical information reproducing apparatus for reproducing information by irradiating a reference light to an optical information recording medium,
A reproduction light generator that irradiates the optical information recording medium with the reference light and generates reproduction light including header information corresponding to the information;
A light beam splitting unit that splits the reproduction light generated by the reproduction light generation unit into a plurality of pieces so as to include the header information, respectively;
An imaging unit that captures the reproduction light divided by the dividing unit;
A control unit that processes header information of the reproduction light imaged by the imaging unit;
An optical information reproducing apparatus comprising: The optical information reproducing apparatus according to claim 1,
A magnifying optical unit that magnifies the information contained in the reproduction light before the reproduction light is divided by the light beam dividing unit;
An optical information reproducing apparatus comprising: The optical information reproducing apparatus according to claim 1,
A reflection unit that reflects the reproduction light so as to be incident on the imaging unit;
An optical information reproducing apparatus characterized in that a distance from the reflecting unit to the imaging unit is larger than four times the diameter of the light beam of the reproducing light. The optical information reproducing apparatus according to claim 1,
The light beam splitting unit is a beam splitter prism,
The beam splitter prism includes an incident surface perpendicular to the incident optical axis of the reproduction light, and a reflective surface inclined by θ degrees with respect to the incident surface,
One side of the reflection boundary of the reflecting surface is on the incident surface and is arranged at the approximate center of the incident light flux,
The exit surface of the reflected light reflected by the reflecting surface is disposed at 2θ degrees with respect to the incident surface,
An optical information reproducing apparatus in which θ is set to an angle between 45 degrees and 70 degrees. The optical information reproducing apparatus according to claim 4,
The optical information reproducing apparatus, wherein the beam splitter prism includes a semi-reflective region in the vicinity of the reflection boundary on the one side. The optical information reproducing apparatus according to claim 1,
The beam splitting unit is a reflecting mirror,
The reflecting mirror is disposed at an angle of θ with respect to the incident optical axis of the reproduction light,
The output optical axis of the reproduction light reflected by the reflecting mirror forms 2θ degrees with respect to the incident optical axis of the reproduction light,
The optical information reproducing apparatus according to claim 1, wherein the one side serving as a reflection boundary of the reflecting mirror has an angle of θ degrees or less. The optical information reproducing apparatus according to claim 6,
The optical information reproducing apparatus, wherein the reproduction light reflected by the reflecting mirror is arranged in a direction intersecting with a light beam of the reproducing light not reflected by the reflecting mirror. The optical information reproducing apparatus according to claim 1,
The controller is
An address pattern in which a verification code is added to the address value is acquired from the header information included in the reproduction light, the address value is verified using the verification code included in the address pattern, and the verified address value is validated. An optical information reproducing apparatus, wherein the address information is selected as a unique address value. The optical information reproducing apparatus according to claim 1,
When a sync mark is included in the header information, an image photographed by the imaging device is aligned with respect to the sync mark as a reference, and is combined into one composite image data, and a decoding process is performed on the composite image data. An optical information reproducing apparatus which performs error correction processing after performing interleaving processing. The optical information reproducing apparatus according to claim 1,
Optical information characterized by decoding an image photographed by the imaging device, synthesizing the decoded decoded data into a single synthesized data, performing an interleaving process on the synthesized data, and then performing an error correction process Playback device. An optical information reproducing method used in an optical information reproducing apparatus for reproducing an information signal by irradiating an optical information recording medium with reference light,
Irradiating an optical information recording medium with reference light to reproduce an information signal having header information;
Dividing into multiple parts each including header information;
Photographing each of the divided information signals;
An optical information reproducing method for use in an optical information reproducing apparatus.

Images