KR100619050B1 - Method of recording information on hologram memory medium - Google Patents

Abstract

An object of the present invention is to provide an information recording method of a hologram memory medium which can simplify the control of a recording or reproduction optical system while increasing the recording capacity.

Each piece of information is sequentially recorded in an information recording area (area) of a hologram memory medium in the form of a card along a predetermined route while maintaining a predetermined interval.

Description

Method of recording information on hologram memory medium

1 is a conceptual diagram when information is recorded in a spiral shape.

2 is a diagram illustrating an adjacent gap.

3 is a conceptual diagram when an interference stripe is recorded in a spiral shape.

4 is a conceptual diagram when information is recorded in another recording form.

5 is a diagram illustrating an adjacent gap.

6 is a conceptual diagram in the case where an interference stripe is recorded by another recording type.

7 is a diagram illustrating a configuration of a hologram memory medium.

8 is a diagram illustrating a configuration of an information recording apparatus.

9 is a diagram illustrating a configuration of an optical system.

10 is an information recording processing flowchart in this embodiment.

11 is a conceptual diagram showing a conventional recording method.

<Description of the code>

1: hologram memory medium

2, 6: substrate

3: hologram recording layer

4: total reflection layer

5: protective layer

7: feet

10: Motor for moving hologram memory medium

11: optical pickup

12: feed motor

13: signal processing IC

14: CPU

15: Driver IC

20: Optical system for data recording reproduction

30: optical system for positioning control

TECHNICAL FIELD The present invention relates to a memory medium, and more particularly, to an information recording method of a hologram memory medium for recording information in a hologram memory medium as interference stripes by object light and reference light.

Recently, a rewritable optical disc such as a phase change type or a magneto-optical type is widely used as a recording medium for information. In order to further increase the recording density, such an optical disc requires a technique of shortening the distance between adjacent tracks or adjacent bits by reducing the beam spot diameter.

As described above, the density of optical discs is increasing year by year. On the other hand, since the optical disc records data in plane, its recording density is limited to the diffraction limit of light, and the physical limit of high density recording is approaching. Therefore, three-dimensional (volume-type) multiple recording including the depth direction is necessary for the large capacity.

Thus, attention has been paid to hologram memories having both high capacity derived from three-dimensional multiple recording areas and high speed derived from two-dimensional collective recording and reproduction methods as next-generation computer file memories. The hologram memory irradiates object light and reference light corresponding to the recording information onto a recording medium formed by sandwiching two glass plates with a recording layer made of photopolymer or the like, for example. By recording the interference stripe as a change in the refractive index of the recording material, when the information is reproduced, only the reference light is irradiated to the recorded interference stripe, and optical information corresponding to the recording information is extracted.

In addition, various types of hologram memory have been proposed, such as a cube type or a card type. For example, a hologram memory having a multi-layered recording layer in which a waveguide is formed to increase the recording capacity is known. For example, see Japanese Patent Laid-Open No. 2000-67204.

In general, however, in the case of recording or reproducing information in the hologram memory, for example, as shown in Fig. 11, the information is recorded or reproduced in the horizontal direction along the reference line, and once the end of the reference line is reached, the recording is performed. Alternatively, the reproducing operation is stopped to move to the next reference line adjacent to each other, and as described above, the operation of executing recording or reproducing of information in the horizontal direction along the reference line is repeated. However, in the recording and reproducing method, since the recording or reproducing operation is stopped once at each end of each reference line, the continuity of the recording or reproducing operation is lost, and the control of the recording or reproducing optical system becomes complicated. There was.

SUMMARY OF THE INVENTION The present invention has been made in an effort to provide an information recording method of a hologram memory medium which can simplify the control of a recording or reproduction optical system while increasing the recording capacity.

In order to achieve the above technical problem, the present invention proposes an information recording method of a hologram memory medium, characterized in that each information is sequentially recorded at predetermined intervals according to a predetermined route in an information recording area of a card-shaped hologram memory medium. Doing.

According to the present invention, a series of information can be recorded sequentially on a card-shaped hologram memory medium without interruption. Also in the reproduction of information, it is possible to continuously reproduce the information without causing unnecessary operation to an optical system such as an optical pickup that reads information from a card-like hologram memory medium.

In order to achieve the above technical problem, the present invention proposes an information recording method of a hologram memory medium, wherein the predetermined route has a spiral shape in the information recording method of a hologram memory medium.

According to the present invention, since the recording route is a spiral shape, the information recording area of the card-shaped hologram memory medium can be used as effectively as possible, and a series of information can be recorded sequentially without interruption.

In order to achieve the above technical problem, the present invention sequentially records information recorded in the information recording area of the card-shaped hologram memory medium from the center of the card to the outer edge, or from the outer edge to the center in the information recording method of the hologram memory medium. There is proposed an information recording method of a hologram memory medium characterized by recording.

According to the present invention, since the information is recorded from the center of the card to the outer edge or from the outer edge to the center, the information recording area of the card-shaped hologram memory medium can be used as effectively as possible, and the operation unnecessary for the recording optical system. You can record the information continuously without making it work.

In order to achieve the above technical problem, the present invention is characterized in that in the information recording method of a hologram memory medium, the predetermined route has a plurality of reference lines parallel to each other, and the end of each reference line and the start of the subsequent reference line are connected to each other. An information recording method of a hologram memory medium is proposed.

According to the present invention, since the recording route has several reference lines parallel to each other, and the end portion of each reference line and the starting end portion of the subsequent reference line are connected to each other, the information recording area of the card-shaped hologram memory medium is effectively as effectively as possible. At the same time, a series of information can be recorded sequentially without interruption.

In order to achieve the above technical problem, the present invention provides an information recording method of a hologram memory medium in which the information recorded in the information recording area of the card-shaped hologram memory medium is opened from the corresponding end of one reference line having an open end among the reference lines. There is proposed an information recording method of a hologram memory medium, which is sequentially recorded up to the corresponding end of the other reference line having the defined end.

According to the present invention, since the recording route is recorded from the end of one reference line having an open end of the reference line to the end of the other reference line having an open end, the information recording area of the card-shaped hologram memory medium is as long as possible. At the same time, the information can be recorded continuously without causing unnecessary operation to the recording optical system.

In order to achieve the above technical problem, the present invention proposes an information recording method of a hologram memory medium, wherein in the information recording method of a hologram memory medium, a recording shape of a close distance at which the recording direction of the information changes is curved. have.

According to the present invention, since the recording shape between the close distances in which the recording direction of the information changes is curved, the servo followability of the optical system such as optical pickup can be sufficiently secured even in the portion where the recording direction of the information changes.

In order to achieve the above technical problem, the present invention proposes an information recording method of a hologram memory medium, in which the information is recorded by a two-dimensional shift multiplexing method in the information recording method of a hologram memory medium.

According to the present invention, a large capacity of recording information can be realized in that a two-dimensional shift multiplexing method is used as the information recording method.

In order to achieve the above technical problem, the present invention is characterized in that, in the information recording method of a hologram memory medium, adjacent intervals of several parallel reference lines forming the spiral shape are equal to the amount of shift in two-dimensional shift multiplexing. An information recording method of a hologram memory medium is proposed.

According to the present invention, since adjacent intervals of several parallel reference lines forming a spiral shape are the same as the amount of shift in the two-dimensional shift multiple recording method, the information is continuously recorded without increasing unnecessary recording capacity without causing unnecessary operations on the recording optical system. Can be recorded.

In order to achieve the above technical problem, the present invention provides an information recording method of a hologram memory medium, wherein the adjacent intervals of several reference lines parallel to each other are equal to the amount of shift in two-dimensional shift multiple recording. A recording method is proposed.

According to the present invention, it is possible to continuously record information without increasing the recording capacity without unnecessary operation in the recording optical system in that adjacent intervals of several reference lines parallel to each other are equal to the shift amount in the two-dimensional shift multiple recording method.

Hereinafter, the information recording method of the hologram memory medium according to the embodiment of the present invention will be described in detail with reference to FIGS.

1 to 6 are diagrams illustrating a hologram memory medium in which information is recorded by the information recording method of the hologram memory medium according to the present invention, and FIG. 7 is an example, which is a surface having a cross-sectional view of the hologram memory medium and an information recording area; Servo information (positioning information) provided on the opposing surface is shown.

1 to 3 are formed in a spiral shape in the interference stripe recorded on the hologram memory medium, and FIGS. 4 to 6 each reference line with respect to various reference lines in which the interference stripe recorded in the hologram memory medium is parallel to each other. The end part of and the start end part of the subsequent reference line are formed in the shape which mutually connected.

As shown in Fig. 7, the hologram memory medium 1 includes a substrate 2, a hologram recording layer 3, a total reflection layer 4, a protective layer 5, a coat layer (not shown), and an adhesive layer (not shown). (Not shown), the substrate 6 on which the pits are formed, and the pits 7 are formed. Here, the substrates 2 and 6 are members forming the base of the hologram memory medium 1. The hologram recording layer 3 is made of a photosensitive material such as a photopolymer, for example, and records information of the object light as an interference stripe by irradiating the object light and the reference light at the same place.

The total reflection layer 4 is a layer that reflects the object light and the reference light incident on the hologram recording layer 3, and prevents the object light and the reference light from passing through the surface facing the surface having the information recording area. The protective layer 5 physically protects the servo information (pit 7) formed on the substrate 6, for example, in a concave or protruding shape from the outside.

The pit 7 has optical system servo information such as an optical pickup for recording or reproducing information. Therefore, the position of the recording / reproducing optical system can be controlled very appropriately by optically reading the servo information from the substrate 6 side.

Further, the pit rows have a symmetrical shape with that of the interference stripe recorded on the hologram memory medium. For example, when the recording of the interference stripe has a spiral shape, the pit row has a spiral shape that is symmetrical with this.

In addition, as shown in Figs. 2 and 5, the adjacent intervals W _S of several reference lines parallel to each other are set to be the same as the shift amount in the two-dimensional shift multi-recording method because they are adapted to the two-dimensional shift multi-recording method. It is. Thus, similarly the distance pit string, and it is configured such that W _S. In the above-described recording form, conceptual diagrams in the case where the interference stripe is actually recorded by the two-dimensional shift multiplexing method are shown in FIGS. 3 and 6.

Further, recording information corresponding to TOC information on the CD is recorded at a predetermined position in the information recording area. The information recorded in the information recording area includes the actual record information and the position information (address information) recorded for each predetermined data column. Therefore, by using the information corresponding to the TOC information and the address information of each data string, it is possible to access the desired data string.

Subsequently, the information recording apparatus for executing the information recording method of the hologram memory medium according to the present invention includes a motor 10 for moving the hologram memory medium, an optical pickup 11, a feed motor 12, as shown in FIG. The signal processing IC 13 is composed of a central processing unit (CPU) 14 and a driver IC 15.

The hologram memory medium moving motor 10 moves the hologram memory medium 1 in a direction different from the reference line in the hologram memory medium 1 by a distance equal to the shift amount in the shift multiplexing. In addition, the movement of the motor 10 for hologram memory medium movement is controlled by the output of the driver IC 15 mentioned later.

The optical pickup 11 includes a laser light source by a semiconductor laser, an optical lens such as an object lens driven by a collimator lens, a focus actuator or a tracking actuator, a polarizing beam splitter, a light receiving element, and the like.

The feed motor 12 moves the optical pickup 11 to a desired position in the hologram memory medium 1, in particular to the hologram memory medium 1 supplied from the driver IC 15 in the search operation, for example. The position of the optical pickup 11 is controlled by an appropriate drive voltage obtained based on the recorded address information and the like.

The signal processing IC 13 generates a reproduction signal based on the amount of returned light from the hologram memory medium 1 incident on the light receiving element, and simultaneously detects a focus error of the irradiation laser in the optical pickup 11. The signal FE is generated by the astigmatism method or the like based on, for example, the amount of returned light obtained by the light receiving element in the optical pickup 11, and further, the error in the reference line direction of the irradiation laser in the optical pickup 11 is generated. The track error signal TE to be detected is generated by, for example, a push pull method. Also, based on the generated FE and TE, a focus driving signal FODDR and a tracking driving signal TRDRV are generated.

The CPU 14 performs control of the entire apparatus based on a control program stored in a ROM (Read Only Memory) or the like. In the present invention, various servo operations are controlled in the operation of writing information to the hologram memory medium. In particular, in the retrieval operation, a drive voltage for the feed motor 12 necessary for the optical pickup 11 to move is calculated from the current address information and the address information of the target position, and this is performed by the signal processing IC 13. To the driver IC 15.

The driver IC 15 inputs the focus drive signal FORDRV or tracking drive signal TRDRV generated by the signal processing IC 13, amplifies it to a desired magnitude, and supplies the same to a focus actuator or a tracking actuator.

In addition, as shown in FIG. 9, the optical system of the information recording apparatus includes a data recording and reproducing optical system 20 for recording information in an information recording area of the hologram memory medium 1 and reproducing the recorded information, and a hologram. And a positioning control optical system 30 for performing positioning control of the optical pickup 11 when recording and reproducing information to the memory medium 1. In addition, the data recording and reproducing optical system 20 and the positioning control optical system 30 are mechanically integrated, and the positioning control optical system 30 also moves in conjunction with the movement of the data recording and reproducing optical system 20. .

Next, the information recording method of the hologram memory medium according to the present invention will be described with reference to FIG.

First, when the hologram recording medium 1 is attached to the information recording apparatus (step S101), the CPU 14 feeds necessary for the optical pickup 11 to move based on the address information obtained from the optical system 30 for positioning control. The drive voltage for the motor 12 is calculated, and is then supplied to the driver IC 15 via the signal processing IC 13, whereby the optical pickup (in the home position where the recording information in the hologram recording medium 1 is recorded) 11) to move (step S102).

Subsequently, the CPU 14 reads out information corresponding to TOC information recorded near the home position from the reproduction signal from the positioning control optical system 30 to determine whether the information has already been recorded on the hologram recording medium 1. (Step S103). As a result of determination, when nothing is recorded on the hologram recording medium 1, the data recording and reproducing optical system 20 is moved to a predetermined recording start position (step S104).

On the other hand, when information is already recorded on the hologram recording medium 1, the optical system 20 for data recording and reproduction is shifted to an address shifted by an amount corresponding to the shift multiple shift amount with respect to the address of the last recorded information. Move (step S105). When the data recording and reproducing optical system 20 moves to a predetermined position, the object light and the reference light are irradiated to the information recording area of the hologram recording medium 1 from the data recording and reproducing optical system 20, and the desired information is recorded as an interference stripe. (Step S106). Thereafter, the data recording and reproducing optical system 20 performs a recording operation while shifting by a predetermined amount based on the positioning information obtained from the positioning control optical system 30.

Therefore, according to the information recording method of the hologram memory medium according to the present embodiment, the information recording area of the card-type hologram memory medium can be effectively used, and a series of information can be continuously recorded and reproduced. In addition, the two-dimensional shift multiple recording method can be easily coped with.

As mentioned above, although the Example of this invention was described above with reference to drawings, the specific structure is not limited to these embodiment, The design change etc. of the range which do not deviate from the summary of this invention are included. For example, in this embodiment, the card type hologram memory medium is not specifically specified, but the information recording method of the hologram memory medium according to the present invention is a recordable medium by photopolymer, a rewritable medium by LiNb03, or the like, or It can be widely applied to a multilayer waveguide-type medium and the like.

Although the foregoing description has been focused on the novel features of the invention as applied to various embodiments, those skilled in the art will appreciate that the apparatus and method described above without departing from the scope of the invention. It will be understood that various deletions, substitutions, and changes in form and detail of the invention are possible. Accordingly, the scope of the invention is defined by the appended claims rather than in the foregoing description. All modifications within the scope of equivalents of the claims are to be embraced within the scope of the present invention.

According to the present invention, since the control of the recording or reproducing optical system can be simplified while increasing the recording capacity, there is an effect that an efficient recording and reproducing operation of information can be realized.

Claims (9)

An information recording method of a hologram memory medium, characterized by sequentially recording each information along a predetermined route in a spiral shape in an information recording area of a hologram memory medium in the form of a card. delete The method of claim 1, The information recording method of the hologram memory medium, characterized in that the information recorded in the information recording area of the card-shaped hologram memory medium is sequentially recorded from the center of the card to the outer edge portion or from the outer edge to the center portion. . The information recording area of the card-shaped hologram memory medium has various reference lines parallel to each other, and each piece of information is arranged along a predetermined route, which is a shape in which the end of each reference line and the start of the subsequent reference line are connected to each other. Records sequentially while maintaining a predetermined interval, And the information is recorded by a two-dimensional shift multiplexing method, wherein adjacent intervals of several baselines parallel to each other are equal to the amount of shift in the two-dimensional shift multiplexing. The method of claim 4, wherein Information recorded in the information recording area of the card-shaped hologram memory medium is sequentially recorded from the corresponding end of one reference line having an open end to the corresponding end of the other reference line having an open end. An information recording method of a hologram memory medium. The method according to any one of claims 1 and 3 to 5, An information recording method of a hologram memory medium, characterized in that a recording shape between near distances at which the recording direction of the information changes is curved. The method according to claim 1 or 3, And the information is recorded by a two-dimensional shift multiplexing method. The method of claim 7, wherein The information recording method of a hologram memory medium, characterized in that an interval in which multiple reference lines parallel to each other forming the spiral shape are adjacent to each other is equal to the amount of shift in two-dimensional shift multiplexing. delete

Images