KR100756247B1 - Holographic Storage consisting the Mirror with translation and rotation - Google Patents

Abstract

The present invention relates to a hologram storage device, and more particularly to a hologram storage device that can easily implement the angle multiplexing technique by changing the reference light reflection angle and position in a three-dimensional hologram drive as a mass storage device. The hologram storage device of the present invention includes a pair of mirrors for reflecting reference light, wherein each pair of mirrors is characterized by translational and rotational motions. According to the present invention, there is an advantage of using a translation stage with easy control of sub-micro units and using only one set of mirrors per optical path.

Hologram, optical disc, recording medium, translation, rotation

Description

Holographic Storage consisting of the Mirror with translation and rotation

1 is a conventional hologram storage device comprising fixed media.

2 is a conventional hologram storage device comprising rotating media.

3A and 3B illustrate a method of storing data on a recording medium.

4A and 4B illustrate a method of reproducing data on a recording medium;

5 is a configuration diagram of a hologram storage device in which a reference light for recording and a reference light for writing are divided;

6 is a block diagram of a hologram storage device having a mirror for translation, rotational movement according to an embodiment of the present invention

7 is an angle multiplexing method of a first translation mirror and a second translation mirror according to an embodiment of the present invention.

{Description of Signs of Major Parts of Drawings}

601: light source 602: first light splitter

603: optical modulator 604: optical pickup

605: second light splitter 606: reference light reflecting mirror

607: 1st mirror mirror 608: 2nd mirror mirror

609: recording medium 610: object light

611: reference light 612: reference light for writing

613: reference light for reading

The present invention relates to a hologram storage device, and more particularly to a hologram storage device that can easily implement the angle multiplexing technique by changing the reference light reflection angle and position in a three-dimensional hologram drive as a mass storage device.

Recently, the multimedia industry is developing into a highly technology-intensive industry in which various industries such as home appliances, computers, communication, video, and broadcasting are converged. To meet this multimedia industry environment, a new information environment is needed. In other words, as the amount of information is enormous, ultra large capacity, ultra high speed, and ultra small size of information storage media are required. For example, in order to commercialize video-on-demand of multimedia information communication, a video server requires 10 ³ Tb or more and a data transfer rate of 1 Gb / sec or more.

However, current semiconductor memories, magneto-optical discs (MOD) and compact discs (CD) have a technical and economic limitation in this information storage process, and a new generation of ultra-large capacity information storage devices is urgently needed. Currently, CD memory has a capacity of 640MB (1 hour 40 minutes of music or more than 300,000 pages of double-sided documents), but hundreds to tens of thousands in hospitals, law, companies, government agencies, libraries, etc. He's using an expensive Jukebox that stacks disks and accesses them with a robotic arm.

Conventional CD / DVD storage has been a two-dimensional storage method for storing information on one side of media using beam spots collected from a laser light source. In this case, the data storage capacity was increased by adjusting the pitch interval between tracks or increasing the number of layers. However, the reduction of the pitch interval and the increase of the layers have physical limitations. It becomes impossible.

Therefore, the hologram storage method, which is a three-dimensional three-dimensional storage method introduced to overcome this problem, can record information inside the storage medium by using the diffraction and interference effects of light, which is several tens to hundreds compared to CD / DVD. The ship's storage capacity can be secured.

The hologram refers to reproducing or storing the same light waves used when being stored. The hologram memory stores and reproduces two-dimensional light patterns. This storage method can read the information stored in the overlapped space by the appropriate multiplexing technique separately from each other, and reads in units of pages in which two-dimensional images are reproduced at once. Implementation of the system becomes possible.

1 illustrates a basic structure of a conventional hologram memory system.

The laser 1 is split into a reference beam 10 and an object beam 9 to which a signal is to be carried by a beam splitter 2. The object light is modulated into a two-dimensional pattern by desired input data while passing through a spatial light modulator (SLM) 4. This light interferes with the reference light 10 in the media 7 of the photorefractive material to store information. When reading the information, only the reference light 10 is irradiated to the photorefractive material. Then, the signal light carrying the original information is reproduced and incident on a detector array 8 such as a CCD (Charge Coupled Device).

2 is a block diagram of a disk rotating hologram storage device. If FIG. 1 is a hologram storage device using fixed media, the hologram storage device of FIG. 2 is rotated by forming a media similar to an optical disc media of a general CD / DVD, and data is sequentially stored along a track. . However, the media of the disk rotating hologram storage device do not rotate at high speed like a normal CD / DVD. ) Is stored and rotated in stepping fashion.

As a technical method of increasing storage capacity in relation to a hologram drive, an angular multiplexing, a phase multiplexing, a wavelength multiplexing method, and the like have been introduced.

3A and 3B show a method of recording data on a recording medium using an angular multiplexing method, and FIGS. 4A and 4B show a method of reproducing data stored on the medium.

In the angular multiplexing method, the disc incident angle of the reference light is adjusted to improve the storage density of the media so that data recorded at a specific angle can be reproduced only by irradiating the laser again at that specific angle.

In this way, the section in which the angle of the reference light can be selected so that data can be recorded and reproduced is called each selectivity. Currently, a method in which the mirror of the reference light is rotated in one direction and overlapped is selected.

In the angular multiplexing method, a galvanometer or a driving motor is used to change the angle of the reference light. However, in order to improve the storage density, the driving angle resolution of the motor unit must be improved. There was a problem with using the product.

In addition, an increase in the control drive unit for controlling these drive motors may cause problems such as an increase in overall product size and an inefficient component configuration.

The present invention has been made to solve the above problems, an object of the present invention is to provide a hologram storage device including a reference light reflection mirror that can easily change the reference light reflection angle and position.

In order to achieve the above object, the hologram storage device of the present invention includes a pair of mirrors for reflecting the reference light, and each of the pair of mirrors is characterized by performing translational and rotational motions.

In the present invention, the pair of mirrors is preferably adjusted so that the reference light is formed at different angles on the same portion of the storage medium.

In the present invention, it is preferable that only one mirror of the pair of mirrors is moved to write the data recorded on the storage medium.

Only one mirror of the pair of mirrors is preferably moved to read the data recorded on the storage medium.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. In adding reference numerals to components of the following drawings, it is determined that the same components have the same reference numerals as much as possible even if displayed on different drawings, and it is determined that they may unnecessarily obscure the subject matter of the present invention. Detailed descriptions of well-known functions and configurations will be omitted.

6 is a block diagram of a hologram storage device of an angular multiplexing system having a pair of translational, rotating mirrors according to an embodiment of the present invention.

In the above embodiment, the hologram storage device includes a light source 601, a first light splitter 602, a light modulator 603, an optical pickup 604, a second light splitter 605, a reference light reflecting mirror 606, A first translation mirror 607, a second translation mirror 608 and a recording medium 609 are included.

In the above embodiment, the first translation mirror 607 and the second translation mirror 608 perform a translational and rotational motion to perform an angle multiplexing method.

Referring to FIG. 6, the laser beam emitted from the light source 601 is divided into the object light 610 and the reference light 611 by the first light splitter 602. The object light 610 is incident to the optical modulator 603, and the object light 610 incident to the optical modulator 603 is modulated into light including a data signal for storing in the recording medium 609.

The reference light 611 is used by the second light splitter 608 for reading the data stored in the recording reference light 612 and the recording medium 609 used for recording the data on the recording medium 609. It is divided into the reference light 613. The writing reference light 612 is input to the first translation mirror 607, and the reading reference light 613 is incident to the second translation mirror 608.

The first translation mirror 607 and the second translation mirror 608 perform translational and rotational motions. Referring to FIG. 6, the first translation mirror 607 and the second translation mirror 608 perform a linear movement left and right. The first translation mirror 607 and the second translation mirror 608 performing the translational motion rotate about the center of the mirror. As described above, an image by angular multiplexing is formed on the recording medium 609 by translation and rotational motion.

Hereinafter, the method of angular multiplexing will be described in more detail.

7 illustrates an angle multiplexing method of a first translation mirror and a second translation mirror according to an embodiment of the present invention.

Referring to FIG. 7, a pair of pairs of the first and second translation mirrors 607a to 607c and 608a to 608c perform image formation by angular multiplexing. The first translation mirrors 607a to 607c rotate in a clockwise direction according to movement from left to right. The second translation mirrors 608a to 608c rotate in a counterclockwise direction as they translate from left to right.

The first translation mirrors 607a to 607c and the second translation mirrors 608a to 608c relatively change their positions, thereby forming an image by changing only angles at the same positions.

The first translation mirrors 607a to 607c move in translation and rotational motion when recording data on the recording medium, and the second translation mirrors 608a to 608c translate when reading data from the recording medium. Movement and rotational movement will be performed.

As described above, it has been described with reference to the preferred embodiment of the present invention, but those skilled in the art various modifications and changes of the present invention without departing from the spirit and scope of the present invention described in the claims below I can understand that you can.

As described above, according to the present invention, there is an advantage of using a translation stage that allows easy control of sub-micro units and uses only one set of mirrors per optical path.

Claims (4)

Hologram Storage, A light splitter separating the incident light into a reference light and an object light; A spatial light modulator for forming a two-dimensional pattern using the object light as input data; An object light reflection mirror for reflecting the object light toward a recording medium; A pair of reference light reflecting mirrors reflecting the reference light toward the recording medium; Each pair of mirrors holographic storage device, characterized in that for translational and rotational movement. The hologram storage device according to claim 1, wherein the pair of mirrors are adjusted such that the reference light is formed at different angles on the same portion of the storage medium. 3. A hologram storage device according to claim 1 or 2, wherein only one mirror of the pair of mirrors is moved to write data recorded on the storage medium. 3. A hologram storage device according to claim 1 or 2, wherein only one mirror of the pair of mirrors is moved to read the data recorded on the storage medium.

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