KR100453009B1 - Holographic digital data storage/reproducing system and addressing method thereof - Google Patents

Abstract

The present invention relates to a method of addressing a holographic digital data storage and reproducing system. In particular, the holographic digital data storage and reproducing system includes a first reference group and an information group, and a first code and a second reference group each consisting of two bits. After recording the addressing code of each page using two bits sequentially drawn from the including second code, the addressing code of one bit is grouped in m units in the reproduction mode, and the first, By searching the group 2 criteria, information on the currently playing page can be obtained.

That is, the page information can be recorded with the two-bit addressing code, and the page information being reproduced can be read, thereby increasing the recording density of the storage medium and minimizing the code rate loss.

Description

Holographic digital data storage and playback system and addressing method {HOLOGRAPHIC DIGITAL DATA STORAGE / REPRODUCING SYSTEM AND ADDRESSING METHOD THEREOF}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a holographic digital data storage and reproducing system, and in particular, generates addressing codes that can minimize the code rate and improve the recording density of a storage medium, and writes to each page, using the recorded addressing codes A holographic digital data storage and reproducing system for obtaining information and a method of addressing the same.

Currently, holographic digital data storage (Holographic Digital Data Storage) applying semiconductor laser, charge coupled device (CCD), liquid crystal display (LCD), etc. is being actively researched and developed. Holographic digital data storage devices have the advantages of large storage capacity and ultra-fast data transfer speed, so they are not only being used as fingerprint recognition devices and display devices for storing and reproducing fingerprints, but also their application fields are gradually expanding. .

The holographic digital data storage and reproducing apparatus interferes with the object light transmitted from the target object and the reference light, and then reacts the interference fringe generated by the interference according to the amplitude and phase of the interference fringe differently. It records in a storage medium such as a photorefractive crystal to store the three-dimensional hologram data. It blocks the object light and provides only the reference light to the storage medium to reproduce the stored three-dimensional hologram data.

1 is a block diagram showing a holographic digital storage and playback system according to the prior art.

Referring to FIG. 1, a conventional holographic digital storage and system includes a light source 10, a light separator 11, a spatial light modulator (SLM) 11, a first lens 13, and a rotating mirror 14. ), An actuator 15, a reflector 16, a second lens 17, a storage medium 18, a third lens 19, a CCD 20, and a central control unit 30. The optical splitter 11 splits the laser beam of the light source 10 into two, so that the two paths including the plurality of optical systems, that is, the reference light path S ₁ and the object, are separated between the optical splitter 11 and the storage medium 18. An optical path S ₂ is formed.

First, the light separator 11 separates the laser light incident from the light source 10 into the reference light and the light of the object, wherein the reference light of the vertically polarized light is provided in the reference light path S ₂ , and the separated object light Is provided by the object light path S ₁ .

The reference light separated from the optical separator 11 and vertically polarized to the rotating mirror 14 is adjusted through an optical lens (not shown) and extended to an arbitrary size (extended to a sufficient size to cover the size of the object light). The light is incident on the storage medium 18 after being deflected through a reflector 16 at a predetermined angle, for example, a recording or reproducing angle.

On the other hand, the object light which is separated from the light separator 11 and is incident through the opening of the shutter (not shown) is transmitted to the spatial light modulator 12. The shutter keeps open when data is recorded, and keeps cut off when data is reproduced. The spatial light modulator 12 modulates the object light in units of pages of binary data of light and dark, which form pixels, according to external input data. The object light modulated in this manner is incident on the storage medium 18 in synchronization with the reference light.

In the storage medium 18, an interference fringe obtained through the interference between the modulated object light provided from the spatial light modulator 12 and the corresponding reference light is recorded. That is, the light induced phenomenon of the kinetic charge occurs in the storage medium 18 according to the intensity of the interference fringe caused by the interference between the modulated object light and the reference light. An interference fringe of the hologram data is recorded. The holographic digital storage system may move the storage medium 18 to record data or rotate the rotating mirror 14 to record data by using the actuator 15 controlled by the central controller 30.

At this time, the data stored in the storage medium 18 includes an addressing code. The method of recording the addressing code includes a method of recording an addressing code in a test page by inserting one test page for each preset page; There is a method of inserting addressing code by applying a binary differential method to data of each page.

This addressing code is recorded by the vertically polarized reference light in the optical splitter 11. The addressing code recorded in this way can be used to obtain information about the page being played back. You can go directly to the page and play it.

However, the method of recording the addressing code by inserting test pages at preset page intervals sets the test pages at preset intervals, thereby reducing the number of pages that can be recorded by the number of test pages inserted in the storage medium 18. There is a problem of lowering the recording density of the storage medium 18.

The method of inserting an addressing code by applying a binary differential method has a problem in that a code rate decreases because data and an addressing code are recorded together so that data that can be recorded on a page is limited.

For example, when the number of pages to be distinguished is 2 ⁿ , since 2n bits of addressing code are required, the data that can be written on one page is reduced.

On the contrary, during reproduction, the object light separated from the optical separator 12 is blocked by the shutter 14, and the reference light for reproduction is stored through the rotating mirror 14, the reflector 16, and the second lens 17. In the case of the incident signal, the storage medium 18 diffracts the reproduction reference light into which the recorded interference fringe is incident, reproduces the recorded signal, and sends it to the CCD 20. The CCD 20 restores the reproduction signal sent from the storage medium 22 to an electrical signal, outputs three-dimensional hologram data, and transmits an addressing code to the microcomputer 30.

The central control unit 30 obtains the page information reproduced by using the addressing code output from the CCD 20. The addressing code is recorded by inserting one test page for each preset page and recording the addressing code on the test page. When the test page is read, information about which pages are currently being played can be obtained, but accurate page information cannot be obtained.

SUMMARY OF THE INVENTION An object of the present invention is to solve such a problem of the prior art, and includes a first code group consisting of a first reference group, an information group, and m bits having split bits and a second reference group that is shifted by one bit in a predetermined unit. The addressing code of each page is recorded with two bits sequentially drawn from the second code having the second code, and the m addressing codes are grouped in the addressing code of the page being reproduced at the time of reproduction, and the first and second reference among the m bits grouped. A holographic digital data storage and reproducing system capable of reading page information being reproduced using a group and an addressing method thereof are provided.

In order to achieve the above object, the present invention provides a holographic digital data storage and reproducing system for storing holographic digital data and addressing codes on a page basis in a storage medium using reference light and object light separated from a light source. N first reference groups that are successively “on” (or “off”) when the reference page is m, m− (n + 2) between two split bits having a different value from the first reference group Wherein the information group has a combination number S = _{m- (n + 2)} C _a according to the number a being “on” (or “off”), and the first group according to the combination of the information groups. The reference group and two divided bits are repeated to form m * S first codes, and the m bits having b second reference groups are repeated in m * S units, and the second reference group in m * S units. A code for generating second codes formed by shifting by one bit A generation unit, a code recording unit sequentially fetching one bit from each of the first and second codes, and writing them to an addressing area of each page; and a page of a page being reproduced using the addressing code output in units of bits in a reproduction mode. A grouping unit for grouping m addressing codes from an addressing code, a position of the first and second reference groups in the addressing code, and calculating a difference between the start bits of the first and second reference groups; A group reader which reads page information to which the reference group belongs, and reads start page information of the first reference group by using bit values existing before or after the first reference group, and is reproduced from the start page information. The page being reproduced using the value counted up to the addressing code of the page and the page information read by the group reading unit. Include the page read unit for detecting information.

The present invention relates to a method for addressing a holographic digital data storage and reproduction system for storing holographic digital data and addressing codes on a page basis in a storage medium using reference light and object light separated from a light source, wherein the reference page is m When n is the first reference group continuously "on" (or "off"), and "on" (m- (n + 2) of the m- (n + 2) between the two divided bits having a value different from the first reference group) Or “off”) information group having _a combination number (S = _{m− (n + 2)} C _a ) according to the number (a), wherein the first reference group and two groups are determined according to the combination of the information groups. The splitting bits are repeated to form m * S first codes, and m bits having b second reference groups are repeated in m * S units, and the second reference group is shifted by one bit in m * S units. Generating second codes configured to the second codes; Sequentially retrieving each bit one by one and recording them in the addressing area of each page; and grouping m addressing codes from the addressing code of the page being reproduced using the addressing code output in units of bits in the reproduction mode. Searching for the position of the first and second reference groups in the addressing code, calculating a difference between start bits of the first and second reference groups, and reading page information to which the first reference group belongs; The start page information of the first reference group is read using a bit value present before or after the first reference group, and the group reading unit counts the starting page information from the start page information to the addressing code of the playing page. Detecting page information being reproduced using the read page information.

1 is a block diagram illustrating a holographic digital data storage and playback system according to the prior art;

2 is a block diagram illustrating a holographic digital data storage and reproducing system according to the present invention;

3 is a diagram illustrating an addressing area in each page according to the present invention;

4 is a diagram illustrating an addressing code generated by a holographic digital data storage and reproducing system according to the present invention.

5 is an exemplary diagram showing addressing codes grouped for extracting page information during reproduction in the holographic digital data storage and reproducing system of the present invention.

<Description of the code | symbol about the principal part of drawing>

100: light source 101: optical separator

102: spatial light modulator 103: first lens group

104: rotating mirror 105: actuator

106: reflector 107: second lens group

108: storage medium 109: third lens group

110: output unit 120: central control unit

There may be a plurality of embodiments of the present invention, and a preferred embodiment will be described in detail below with reference to the accompanying drawings. Those skilled in the art will be able to better understand the objects, features and advantages of the present invention through this embodiment.

2 is a block diagram illustrating a holographic digital data storage and reproducing system according to the present invention, FIG. 3 is a diagram illustrating an addressing area in each page according to the present invention, and FIG. 4 is a holographic digital data according to the present invention. FIG. 5 is a diagram illustrating an addressing code generated by a storage and reproducing system, and FIG. 5 is an exemplary diagram showing addressing codes grouped for extracting page information during reproduction in the holographic digital data storage and reproducing system of the present invention.

Referring to FIG. 2, the holographic digital data storage and system includes a light source 100, a light separator 101, a spatial light modulator (SLM) 102, a first lens group 103, and a rotating mirror ( 104, an actuator 105, a reflector 106, a second lens group 107, a storage medium 108, a third lens group 109, an output unit 110, and a central control unit 120. Since the optical separator 101 separates the laser light of the light source 100 into two, two paths including a plurality of optical systems, that is, the reference light path S ₁ and an object, are separated between the optical separator 101 and the storage medium 108. An optical path S ₂ is formed.

First, the light separator 101 separates the laser light incident from the light source 100 into reference light and light of an object, wherein the reference light of vertical polarization is provided in the reference light path S ₂ , and the separated object light Is provided by the object light path S ₁ .

The reference light separated from the optical separator 101 and vertically polarized to the rotating mirror 104 is adjusted through an optical lens (not shown) and extended to an arbitrary size (extended to a sufficient size to cover the size of the object light). It is deflected through a reflector 106 at a predetermined angle, for example, a recording or reproducing angle, and then enters the storage medium 108.

Meanwhile, object light that is separated from the light separator 101 and incident through the opening of the shutter (not shown) is transmitted to the spatial light modulator 102. The shutter keeps open when data is recorded, and keeps cut off when data is reproduced. The spatial light modulator 102 modulates the object light in units of pages of binary data of light and dark, which form pixels, according to external input data. The object light modulated as described above is incident to the storage medium 108 in synchronization with the reference light.

In the storage medium 108, an interference fringe obtained through the interference between the modulated object light provided from the spatial light modulator 102 and the corresponding reference light at the time of recording is recorded. That is, the light induced phenomenon of the kinetic charge occurs in the storage medium 108 according to the intensity of the interference fringe caused by the interference between the modulated object light and the reference light, and through this process, interference of hologram data in the storage medium 108 occurs. The pattern is recorded. The holographic digital storage system then records the addressing code in a predetermined area of each page when data is recorded on the storage medium 108.

As shown in FIG. 3, the page stored in the storage medium 108 is divided into a data area 200 in which data to be reproduced is recorded, and an addressing area 210 in which an addressing code is recorded, and the addressing area 210. The current page information being reproduced can be known based on the addressing code recorded in &quot;

The central control unit 120 generates an addressing code consisting of two bits to be recorded in the addressing area 210, records the input data together with the input data in the addressing area of each page through the spatial light modulator 102, and outputs the output from the output unit 110. Read the information of the page currently being reproduced by using the addressing codes, and calculate the deflection angle of the reproduction reference light corresponding to the page requested by the user using the read page information to transmit a control signal to the actuator 105. The transmission is composed of a code generation unit 121, a code recording unit 122, a grouping unit 123, a group reading unit 124, a page reading unit 125, and a page moving unit 126.

The addressing code recorded in the addressing area 210 is generated by the code generating unit 121. The code generating unit 121 continuously shows “on” when the reference page is m as shown in FIG. Or &quot; off &quot; of &quot; on &quot; (or &quot; off &quot;) of m- (n + 2) bits between two division bits 220 having a value different from the first reference group and the first reference group consisting of n bits. Information group having a combination number according to the number (a), wherein the combination of the changed information group and the first reference group and the two division bits are repeated to form m * S first codes, and b second M bits having a reference group are repeated in m * S units, and second codes are generated by shifting the second reference group by one bit in m * S units.

The combination number S of the information groups is expressed by Equation 1 below.

At this time, among the m- (n + 2) bits forming the information group, the number of bits “a” that are “on” (or “off”) should have a value greater than m-2n-2.

The code recorder 122 sequentially draws one bit from each of the first code and the second code generated by the code generator 121 and writes them to the addressing area of each page. Each bit is used as an addressing code.

For example, when the reference page is 10, it has an addressing code as shown in Table 1 below. The first “000” becomes the first reference group, and the fourth and tenth “1” denotes the reference group and the information group. A division bit to be divided, and "A1, A2, A3, A4, A5" is an information group representing page information.

0 0 0 One A1 A2 A3 A4 A5 One

Since the number of “on” (or “off”) in the information group should be greater than 2 from the formula (m-2n-2), the number of combinations is ₅ C ₃ or ₅ C ₄ , and ₅ C ₄ In the case of, ₅ C ₃ is selected since the number of combinations is smaller than 10 of the reference pages.

The code generator 121 generates the first code shown in Table 2 below by repeating the first reference group and the two divided bits according to the combination change of the information group.

Pages One 2 3 4 5 6 7 8 9 10 1 to 10 0 0 0 One 0 0 One One One One 11-20 0 0 0 One 0 One 0 One One One 21-30 0 0 0 One 0 One One 0 One One 31-40 0 0 0 One 0 One One One 0 One 41-50 0 0 0 One One 0 0 One One One 51-60 0 0 0 One One 0 One 0 One One 61-70 0 0 0 One One 0 One One 0 One 71-80 0 0 0 One One One 0 0 One One 81-90 0 0 0 One One One 0 One 0 One 91-100 0 0 0 One One One One 0 0 One

Then, the code generation unit 121 is composed of 10 bits having a second reference group of one bit, for example, by shifting the value of the second reference group by one bit in units of m * S (100) by the following table Generate a second code equal to 3.

Pages One 2 3 4 5 6 7 8 9 10 1 to 100 One 0 0 0 0 0 0 0 0 0 101-200 0 One 0 0 0 0 0 0 0 0 201 to 300 0 0 One 0 0 0 0 0 0 0 301-400 0 0 0 One 0 0 0 0 0 0 401-500 0 0 0 0 One 0 0 0 0 0 501 to 600 0 0 0 0 0 One 0 0 0 0 601-700 0 0 0 0 0 0 One 0 0 0 701-800 0 0 0 0 0 0 0 One 0 0 801 to 900 0 0 0 0 0 0 0 0 One 0 901-1000 0 0 0 0 0 0 0 0 0 One

The code recorder 122 extracts one bit from each of the first and second codes generated by the code generator 121 and records the predetermined bits of each page through the spatial light modulator 102. One bit is repeatedly fetched in hundreds.

The method of recording the addressing code by the code recording unit 122 is controlled by the actuator 105 which rotates the rotating mirror 104 to move up and down the ankle multiplexing and storage medium 108 which records a data page including the addressing code. There is shift multiplexing to move and record the data page 200 including the addressing code. The addressing code is also recorded in the addressing area 210 which is the upper left of each page for recording data.

A case where data having an addressing code recorded by the above method is reproduced will be described below.

When the object light separated from the optical separator 101 is blocked through the shutter and the reproduction reference light enters the storage medium 108 through the rotating mirror 104 and the reflector 106, the recorded interference in the storage medium 108 is recorded. The reproduced reference light is diffracted by the pattern incident, and the recorded signal is reproduced and sent to the output unit 110 through the third lens group 109. The output unit 110 outputs the hologram data by reconstructing the reproduction signal sent from the storage medium 108 into an electrical signal and processing the signal in bits (pixels), wherein the output data is processed in bits instead of pages. CMOS is used to do this.

The third lens group 109 adjusts the interference fringe reconstructed by the storage medium 108 to match the number of bits (pixels) and transmits the adjusted fringe to the output unit 110.

Before outputting data, the output unit 110 processes the addressing code recorded in each page in units of bits and transmits it to the central controller 120.

The grouping unit 123 groups m addressing codes from the addressing codes of the page being reproduced by using the addressing codes output in units of bits.

The group reading unit 124 searches the positions of the first and second reference groups in the grouped addressing code, calculates the difference between the start bits of the first and second reference groups, and reads the start page information to which the first reference group belongs. do.

The page reader 125 counts from the start page information of the first reference group to the addressing code of the page being reproduced using the bits of the predetermined number of information groups existing between the divided bits around the first reference group, and reproduces the current playback. Detects page information in progress.

The page shifting unit 126 calculates the deflection angle of the reproduction reference light for reproducing the reproduction request page using the page information being reproduced by the page reading unit 125 in response to an arbitrary reproduction request signal, and calculated The reference light for reproduction is deflected at the deflection angle to enter the storage medium 108.

The storage medium 108 outputs the reproduction request page to the outside through the third lens group 109 and the output unit 110 according to the incident reproduction reference light.

A process of reading information of a page currently being reproduced by using an addressing code recorded in a predetermined area among a page area composed of a plurality of pixels using the holographic digital storage and reproducing system having the above configuration will be described below. .

First, the code generator 121 generates a first code consisting of 100 bits, as shown in Table 2, with the reference page m as 10 pages, and generates a first code consisting of 100 bits as shown in Table 3. 2 Generate the code. In this case, the first code is a first reference group consisting of three bits of "000", an information group consisting of five bits, and three bits are "1", and two bits for dividing the first reference group and the information group are "1". In splitting bits. The first code is bits indicating information of 1 to 100 pages, and the position of 3 bits which becomes "1" of 5 bits of the information group is changed in units of 10 pages. That is, the position of three bits which becomes "1" out of five bits of the information group is changed while the first reference group and the split bit remain unchanged. The second code consists of a second reference group having a value of "1" and nine bits having a value of "0". The second reference group has its position changed in units of 100 pages. That is, "1000000000" is sequentially repeated from 1 to 100 pages, and "0100000000" is sequentially repeated from 101 to 200 pages by one bit transition of the second reference group. A second code capable of representing information is generated. The code recorder 122 fetches sequentially one bit from the first and second codes generated by the code generator 121 to perform an ankle multiplexing or shift multiplexing method. The data is sequentially recorded in predetermined areas. That is, the code recorder 122 fetches the bits corresponding to 1-100 pages from the first code and then fetches the bits corresponding to 1-100 pages from the second code, but “1000000000” of the second code is 10 pages. The bits are repeatedly retrieved in units and the bits extracted from the first and second codes are recorded in the addressing area of the corresponding page. For example, the addressing code corresponding to one page becomes "01", which is a combination of "0" of the first code and "1" of the second code, and the addressing code of page 9 corresponds to "1" of the first code. A combination of " 0 " of the second code, " 10 ", and the addressing code of page 212 is a bit corresponding to 12 pages in the first code, that is, a bit corresponding to 200 pages in the " 0 " "00", which is a combination of "0".

In the reproduction mode, the output unit 110 processes the addressing code recorded in each page in bit units and transmits the signal to the central control unit 120, and the grouping unit 123 of the central control unit 120 requests an arbitrary page reproduction. In response to the signal, based on the addressing code " 10 " of the page currently being reproduced, as shown in FIG. 5, the previous 10 addressing codes are extracted and grouped.

The group reading unit 124 searches for the position of the first reference group (group consisting of “000”) and the second reference group (“1”) among the grouped addressing codes to search for the second bit in the first bit of the first reference group. The start page information of the first reference group is read by counting up to the reference group. In other words, since the count result from the first bit "0" of the first reference group to "1", the last bit of the second reference group, is 4, the first reference group is included in 400 page units. .

The page reader 125 finds the information group by using the bit " 1101 " in front of the first reference group and the bit " 111 " That is, the page reader 125 has all bits corresponding to the three bits (4, 5, 6) after the first reference group with reference to Table 2, and all four bits (7, 8, 9) before the first reference group. The first reference group “000” becomes an addressing code of 71, 72, and 73 by reading that the bit corresponding to (10) is “1101” in the range of 67 to 76 pages.

Therefore, the page reading unit 124 detects that the page having “10” as the addressing code is 476 pages by reading that the addressing code “10” of the page currently being reproduced is 76 pages.

When the reproduction request page is 900 pages, the page shifter 125 calculates the deflection angle of the reproduction reference light according to the difference 424 between the page 476 currently being reproduced and the reproduction request page, and rotates the calculated deflection angle. An actuator 105 control signal is generated to rotate the mirror 104, and the actuator 105 rotates the rotating mirror 104 by the deflection angle to inject the reference light for reproduction into the storage medium 108.

The storage medium 108 outputs a reproduction request page (page 900) through the third lens group 109 and the output unit 110 in response to the reproduction reference light.

As described above, the present invention addresses each page using two bits sequentially drawn from a first code consisting of a first reference group, an information group, a split bit consisting of two bits, and a second code including a second reference group. After the code is recorded, one bit of the addressing code is grouped in m units in the reproduction mode, and the first and second reference groups are searched in the grouped m bits to obtain page information currently being reproduced.

That is, the page information can be recorded with the two-bit addressing code, and the page information being reproduced can be read, thereby increasing the recording density of the storage medium and minimizing the code rate loss.

Claims (8)

A holographic digital data storage and reproduction system for storing holographic digital data and addressing codes on a page basis in a storage medium by using reference light and object light separated from a light source. N first reference groups that are successively “on” (or “off”) when the reference page is m, of m− (n + 2) between two division bits having a different value from the first reference group The information group having _a combination number S = _{m- (n + 2)} C _a according to the number a being “on” (or “off”), the first criterion according to the combination of the information groups The group and two division bits are repeated to form m * S first codes, and the m bits having b second reference groups are repeated in m * S units, and the second reference group is in m * S units. A code generator for generating second codes configured by shifting by one bit; A code recording unit for sequentially drawing one bit from each of the first and second codes and writing the same to the addressing area of each page; A grouping unit for grouping m addressing codes from the addressing codes of the page being played using the addressing codes output in units of bits in the reproduction mode; A group reader for searching the positions of the first and second reference groups in the addressing code, calculating a difference between start bits of the first and second reference groups, and reading page information to which the first reference group belongs; The start page information of the first reference group is read using a bit value present before or after the first reference group, and the group reading unit counts the starting page information from the start page information to the addressing code of the playing page. And a page reader for detecting page information being reproduced by using the read page information. The method of claim 1, A deflection angle of the reference light corresponding to the reproduction request page is set based on the read page information among pages stored in the storage medium, or the position of the storage medium is changed to change the reproduction request page. And a page shifting unit for reproducing the reproduction request page. The method of claim 1, The addressing area in which the addressing code is recorded is Holographic digital data storage and playback system, characterized in that the upper left of the page. The method of claim 1, The number of bits a that is “on” (or “off”) in the information group is A holographic digital data storage and replay system, characterized in that it has a value greater than m-n-2. A method of addressing a holographic digital data storage and reproduction system for storing holographic digital data and an addressing code in a page unit on a storage medium by using a reference light and an object light separated from a light source, N first reference groups that are successively “on” (or “off”) when the reference page is m, of m− (n + 2) between two division bits having a different value from the first reference group The information group having _a combination number S = _{m- (n + 2)} C _a according to the number a being “on” (or “off”), the first criterion according to the combination of the information groups The group and two division bits are repeated to form m * S first codes, and the m bits having b second reference groups are repeated in m * S units, and the second reference group is in m * S units. Generating second codes constructed by shifting by one bit; Sequentially fetching one bit from each of the first and second codes and writing them to an addressing area of each page; Grouping m addressing codes from the addressing codes of the page being reproduced by using the addressing codes output in bits in the reproduction mode; Retrieving the position of the first and second reference groups from the addressing code, calculating a difference between start bits of the first and second reference groups, and reading page information to which the first reference group belongs; The start page information of the first reference group is read using a bit value present before or after the first reference group, and the group reading unit counts the starting page information from the start page information to the addressing code of the playing page. Detecting page information being reproduced using the read page information. The method of claim 5, A deflection angle of the reference light corresponding to the reproduction request page is set based on the read page information among pages stored in the storage medium, or the position of the storage medium is changed to change the reproduction request page. Replaying the playback request page by moving the data to the playback request page of the holographic digital data storage and reproducing system. The method of claim 5, The addressing area in which the addressing code is recorded is And an upper left corner of the page. The method of claim 5, The number of bits a that is “on” (or “off”) in the information group is A method of addressing a holographic digital data storage and reproducing system, characterized in that it has a value greater than m-n-2.