KR100727776B1 - Method for detecting optical information and optical information detector - Google Patents

Abstract

An optical information detection method and an optical information detector are provided to discriminate whether a data page is abnormal by using head information and remove a detection error of the data page. A photo detector(120) detects an image according to external control. A control module(110) controls the photo detector(120), detects a header of a data page stored in an optical information storing medium(70), analyzes information of the detected header, and judges whether the data page is abnormal. If the data page is normal as a result of the judgment, the control module(110) controls the photo detector(120) and acquires an image of the data page.

Description

Optical information detection method and optical information detector {METHOD FOR DETECTING OPTICAL INFORMATION AND OPTICAL INFORMATION DETECTOR}

1 is an exemplary diagram showing a form of a general data page.

2 is an exemplary diagram showing a structure of a data page for optical information processing according to a preferred embodiment of the present invention.

3 is an exemplary diagram illustrating an example in which initial information and address information are inserted in a header.

4 is a conceptual diagram illustrating a concept in which a data page is stored in an optical information storage medium.

5 is a block diagram showing the configuration of an optical information detector according to a preferred embodiment of the present invention.

6 is a flowchart for describing an operation flow of the optical information detector illustrated in FIG. 5.

<Description of the symbols for the main parts of the drawings>

10: Data page

11: data area

14: Mark

18: header

70: optical information storage medium

100; Optical information detector

110: control module

120: light detector

200: data playback unit

The present invention relates to an optical information detection method and an optical information detector, and more particularly, to detect optical information by using header information to determine whether an abnormality of a data page is detected, thereby eliminating a detection error of the data page. A method, an optical information detector and a data page structure for optical information processing.

In recent years, the demand for mass storage devices has increased due to the popularization of high-definition digital broadcasting services and the high performance of personal computers. In particular, the storage capacity of a compact disk (CD) or a digital versatile disk (DVD) currently being used cannot sufficiently satisfy the above-described requirements, and thus, a next-generation storage device capable of drastically increasing the storage capacity of information and its various Technologies are being actively researched.

One of the systems that are attracting the most attention among systems capable of realizing such a next generation storage device is an optical information processing system using holography, that is, a holographic optical information processing system.

The holographic optical information processing system stores the interference fringe on the optical information storage medium by irradiating a signal light containing data and a reference light provided from an angle different from the signal light at a predetermined position of the optical information storage medium and crossing each other. In addition, when the stored information is reproduced, the reference light is irradiated to the stored interference pattern, and the original data is restored by using diffraction generated by the interference pattern.

In addition, the holographic optical information processing system can store data superimposed on the same location of the optical information storage medium using various multiplexing techniques, and can store the super-large data because the superimposed data can be reproduced separately from each other. You can implement the system. In this case, the multiplexing technique includes angle multiplexing, wavelength multiplexing, phase code multiplexing, and the like.

On the other hand, such a holographic optical information processing system processes data in predetermined page units, and this data in units of pages is called a data page.

1 is an exemplary diagram showing a form of a general data page.

As shown in FIG. 1, the data page 1 has a form in which a plurality of pixels 2a and 2b having an on value or an off value are arranged in a matrix form. In this case, the on pixel 2a generally means a digital bit value '1' and the off pixel 2b means a digital bit value '0', but the reverse configuration may also exist.

The holographic optical information processing system encodes input data and converts the input data into a binary code, and stores the data in an optical information storage medium in a signal light unit in data page units. At this time, the optical modulation to load the data page on the signal light may be performed by a spatial light modulator (SLM).

In the optical information storage medium, data pages stored by the storage process are continuously stored. For example, in the case of a holographic optical disc, tracks are formed according to the rotation direction of the disc, and data pages are continuously stored in each track.

The stored data page is detected through the photo detector. That is, the photodetector photographs and detects an image of a data page appearing by diffraction by reference light. Therefore, the holographic optical information processing system can search for information in data page units.

Since the holographic optical information processing system processes data in units of data pages, it is very important to accurately detect information of a desired data page among a plurality of data pages stored in the optical information storage medium when the optical information is reproduced.

However, in the image of the data page detected through the photo detector, a difference in light distribution occurs due to various causes such as intensity of light, distortion by a lens, scattering and diffraction in the system, and especially between each data page. There is an imbalance. Therefore, in order to accurately detect the information of the data page, a predetermined method for solving an error caused by the imbalance between the data pages is required.

In this manner, conventionally, modulation codes or error correction codes are used to encode data pages, or additional signal processing processes such as interleaving between data pages are applied to increase accuracy when data pages are detected.

However, the above-described methods are difficult to solve when the detection of the data page itself is wrong. That is, if a data page other than the desired data page is detected, the desired data cannot be obtained even with the above methods.

Therefore, the address information of the data page is included in the data area of each data page by another conventional method, and all the images of the data page obtained through the photo detector are decoded to restore the information, and then the address information is searched and analyzed. Thus, a method of identifying whether or not it is a desired data page is also used.

However, even in this case, since address information is detected after the data page information is completely restored, there is a problem that excessive time delay occurs. In addition, when the address information is not the desired data page, it is true that the inefficiency of unnecessary load on the hardware exists because the information of the restored data page must be discarded and a new data page must be detected again.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and a first object of the present invention is to provide an optical information detecting method for efficiently detecting a data page stored in an optical information recording medium.

Another object of the present invention is to provide an optical information detector capable of realizing the optical information detecting method.

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The optical information detecting method according to the present invention for achieving the first object of the present invention comprises the steps of: acquiring an image of the header detection area for detecting the header of the data page stored in the optical information storage medium; Acquiring header information of the data page using the acquired image of the header detection area; Determining whether the data page is abnormal based on the header information; And acquiring an image of the data page if there is no abnormality as a result of the determination.

At this time, in the determining step, it is possible to determine whether the data page is abnormal by comparing the header information with preset header information.

The header may include digital information for determining the validity of the data page and address information of the data page. The digital information may be preset initial information.

In the data page image acquiring step, if there is no abnormality in the determination result, in order to acquire an image of the header detection area, an image of the data page is continuously acquired by acquiring an image of the data page, and the determination result is obtained. If there is a problem, an image of a part of the already scanned data page is discarded.

The optical information detecting method may further include acquiring an image of a mark detection area for detecting a mark of a data page stored in the optical information storage medium and detecting a mark by using the image of the mark detection area. It may also include.

On the other hand, the optical information detector according to the present invention for achieving the above-described second object of the present invention, an optical detector for detecting an image under external control; And controlling the photo detector to detect a header of the data page stored in the optical information storage medium, and analyzing the information of the detected header to determine whether the data page is abnormal. And a control module for controlling to acquire an image of the data page.

The control module controls the photo detector to acquire an image of a header detection area for detecting the header, and detect the header using the acquired image of the header detection area. The control module determines whether the data page is abnormal by comparing the detected header information with preset information. In addition, the control module may control the photo detector to detect a mark for detecting the position of the data page.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. In addition, in describing the preferred embodiment of the present invention illustrated in the drawings, specific technical terms are used for clarity of content. However, it is to be understood that the invention is not limited to these specific selected terms, and that each specific term includes technical synonyms that operate in a similar manner to achieve a similar purpose.

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2 is an exemplary diagram showing a structure of a data page for optical information processing according to a preferred embodiment of the present invention.

As shown in FIG. 2, the data page 10 identifies the data area 11 having data information, the marks 14 and the data area 11 for identifying the position of the data area 11. It consists of a header 18 having information.

The mark 14 is preferably arranged at the upper left of the data page 10. This arrangement is for enabling the quickest detection of the mark 14 at the time of image acquisition of the data page 10. This is because the first step to detect the image of the data page 10 is the position detection of the data page 10, and the photodetector usually starts scanning from the upper left when the image of the data page 10 is detected. Because.

In addition, the mark 14 is disposed outside of the data area 11, i.e., outside the data area 11 so as to facilitate identification. At this time, the mark 14 may have a high light quantity. For example, the mark 14 has a plurality of On pixels arranged in succession. Of course, depending on the implementation environment, vice versa, a continuous arrangement of Off pixels is also possible.

The header 18 has identification information for determining a detection error of the data area 11. In other words, the header 18 may be regarded as an identifier of the data page 10. The header 18 is disposed outside the data area 11 to facilitate identification thereof, but is disposed adjacent to the lower part of the mark 14 as shown in FIG. 2 to enable rapid detection after the mark 14 is detected. desirable.

The header 18 inserts digital information for validity determination and address information of a data area. In this case, the digital information may be predefined initial information. The address information may be track information, layer information, and spot information of a corresponding data area.

The initial information may be n bits of binary data, and the address information may be m bits of binary data, respectively.

For example, the initial information can be represented by 5-bit binary data. In this case, in the case of the alphabet, 'A' = 1, 'B' = 2, ..., 'Z' = 26 may be set and each may be represented by a binary number. If the initial information is 'DAEWOO', 'D' is 4, 'A' is 1, 'E' is 5, 'W' is 23, and 'O' is 15, so that if each is converted to binary, [[00100] , [00001], [00101], [10111], [01111], and [01111].

In addition, address information can be represented with 8-bit binary data. When the address information is '24track-129multiplexed layer-5spot', it is expressed as [[00011000], [10000001], [00000101]] when converted to binary.

3 shows an example in which the initial information and address information converted as described above are inserted into a header, and initial information 18a and address information 18b are inserted into the header 18, It can be seen that it is encoded with a binary differential code to increase reliability.

Meanwhile, the data page 10 having such a data page structure may be stored in an optical information storage medium through a spatial light modulator.

4 is a conceptual diagram illustrating a concept in which a data page 10 is stored in an optical information storage medium.

Referring to FIG. 4, the encoding unit 50 encodes data input from the outside for each data page and provides the encoded data to the spatial light modulator 60. In this case, the encoding unit 50 encodes and provides the aforementioned header information together with the data information and the mark information.

The spatial light modulator 60 loads the data provided from the encoding unit 50 into the signal light in the form of a data page 10 having the structure shown in FIG. 2 and irradiates it to the optical information storage medium 70. In this case, the reference information beam irradiated from an angle different from the signal beam is irradiated to the optical information storage medium 70. Therefore, the interference pattern 71 of the data page 10 is stored in the optical information storage medium 70.

5 is a block diagram showing the configuration of an optical information detector according to a preferred embodiment of the present invention.

As shown in FIG. 5, the optical information detector 100 according to the preferred embodiment of the present invention is composed of a photo detector 120 and a control module 110, and is interoperable with the data reproducing unit 200.

The photo detector 120 detects an image of a data page stored in the optical information storage medium 70 under the control of the control module 110. In this case, the photodetector 120 may be a complementary metal-oxide semiconductor (CMOS) or a charge coupled device (CCD).

In the image detection area of the photodetector 120, a mark detection area and a header detection area are set in an area corresponding to the positions of the mark and the header so as to acquire an image of the mark and the header of the data page.

The control module 110 controls the photodetector 120 to acquire an image of the header detection region, analyzes the information of the header to determine whether the detected data page is abnormal, and if there is no abnormality, the photodetector 120 Control to acquire all the images of the data page. In addition, the control module 110 controls the photodetector 120 to acquire an image of the mark detection region before the image acquisition of the header detection region, and analyzes the image to detect the mark.

The control module 110 may be linked with the data reproducing unit 200. The data reproducing unit 200 receives an image of the acquired data page and reproduces original data. The data reproducing unit 200 may include a channel decoder for decoding the contents of the data page.

FIG. 6 is a flowchart for describing an operation flow of the optical information detector 100 shown in FIG. 5.

5 and 6, first, the control module 110 acquires an image of a mark detection region set in the image detection region by controlling the photo detector 120 to obtain an image of a desired data page. (Step: S1).

In this case, as described above, the photodetector 120 starts scanning horizontally from the upper left of the image detection area and repeats horizontal scanning downward. Thus, the mark may be acquired first because it is located at the upper left of the data page.

When the mark is detected, the control module 110 controls the photodetector 120 to continuously scan the image detection area until the image of the header detection area is completely acquired. At this time, since the header is located adjacent to the lower part of the mark, detection is possible even when only a part of the data area is scanned.

When scanning to the header detection area is completed, the control module 110 acquires an image of the header detection area from the photodetector 120 (step: S2), decodes it, and restores the header information (step: S3). . The decoding may be performed by the control module 110 itself, but may be performed by the data reproducing unit 200 interworking with the control module 110 according to an implementation environment.

When the header information is restored, the control module 110 analyzes the header information to determine whether there is an abnormality of the detected data page (step: S4).

That is, validity is determined by comparing digital information in the header with preset digital information, and address information of the header is compared with address information of a desired data page to determine whether another data page is detected.

For example, if the initial information, which is digital information of the header, is different from the preset information, the data page is detected again because there is a high probability that the information of the data page is invalid. Also, if the address information is different from the desired address information, it can be regarded that another data page has been detected, and thus another data page must be detected. Through this process, an invalid data page or an unwanted data page can be prevented from being detected.

Subsequently, if there is no abnormality in the determination result header information, the control module 110 controls the photodetector 120 to acquire an image of a data page (step S5). In other words, all the images of the data page may be acquired by scanning all remaining portions that have not been scanned by the light detector.

On the other hand, if there is an error in the header result of the determination, the image of the already scanned data area is discarded and a new data page is searched again.

Meanwhile, the obtained image of the data page may be reproduced as original data through the data reproducing unit 200.

Although the present invention has been described above with reference to its preferred embodiments, those skilled in the art will variously modify the present invention without departing from the spirit and scope of the invention as set forth in the claims below. And can be practiced with modification. Accordingly, modifications to future embodiments of the present invention will not depart from the technology of the present invention.

As described above, according to the present invention, after determining whether there is an abnormality of the detected data page by using the information of the header included in the data page, an image of the data page can be obtained, and thus an invalid data page is detected. Therefore, the problem that unwanted data pages are detected can be solved. Therefore, the detection error of the data page can be eliminated.

Claims (20)

Acquiring an image of a header detection area for detecting a header of a data page stored in the optical information storage medium; Acquiring header information of the data page using the acquired image of the header detection area; Determining whether the data page is abnormal based on the header information; And And acquiring an image of the data page if there is no abnormality as a result of the determination. The method of claim 1, wherein in the determining step, the header information is compared with preset header information to determine whether the data page is abnormal. The method of claim 1, wherein the header, Digital information for determining validity of the data page; And And the address information of the data page. The method of claim 2, wherein the digital information is predetermined initial information. The method of claim 1, further comprising: acquiring an image of a mark detection area for detecting a mark of a data page stored in the optical information storage medium; And And detecting a mark by using an image of the mark detection area. The method of claim 1, wherein the acquiring of the data page image comprises continuously scanning an image of a portion of the data page that has already been scanned in order to acquire an image of the header detection area, if there is no abnormality in the determination result. And if there is an abnormality in the determination result, an image of a part of the already scanned data page is discarded. An optical detector for detecting an image according to external control; And The optical detector is controlled to detect a header of a data page stored in an optical information storage medium, and the information of the detected header is analyzed to determine whether the data page is abnormal. If the determination result is not abnormal, the optical detector is controlled. And a control module for acquiring an image of the data page. 8. The method of claim 7, wherein the control module controls the photo detector to acquire an image of a header detection area for detecting the header, and detect the header using the acquired image of the header detection area. Optical information detector. 8. The optical information detector of claim 7, wherein the control module detects a mark for detecting a position of the data page by controlling the optical detector. The optical information detector of claim 7, wherein the control module determines whether the data page is abnormal by comparing the detected header information with preset information. The method of claim 7, wherein the header, Digital information for determining validity of the data area; And And the address information of the data area. 8. The optical information detector of claim 7, wherein the header is located at a location separate from a data area having data information of the data page. delete delete delete delete delete delete delete delete

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