WO2013100656A1 - Optical information processing apparatus and method for controlling same - Google Patents

Abstract

The present invention relates to an optical information processing apparatus and to a method for controlling same. Provided is an optical information processing apparatus and a method for controlling same, the optical information processing apparatus comprising: a light source for irradiating light; an optical modulator for modulating the light irradiated from the light source; an optical system for collecting the light modulated by the optical modulator and enabling the modulated light to be incident to an optical medium; a stage on which the optical medium is placed; an optical detection unit for detecting the pattern of the light reflected from the optical medium; and a control unit for analyzing the pattern of the light detected by the optical detection unit so as to control the optical system and the location of the stage.

Description

Optical information processing device and control method thereof

The present invention relates to an optical information processing apparatus and a control method thereof, and more particularly, to an optical information processing apparatus for recording information on an optical medium by reading light onto an optical medium or to read information recorded on the optical medium and a control thereof. It is about a method.

Recently, research and development on optical information processing devices such as digital versatile disc (DVD), HD-DVD, Blu-ray disc (BD), near field light processing device, and holographic light processing device have been actively conducted. It's going on.

Among them, the optical information processing apparatus using holography induces a polymerization reaction by irradiating a focused light onto an optical medium made of a photosensitive material such as a photopolymer to record information on the optical medium or to record information on the optical medium. It is operated by reproducing information.

In order for the optical information processing apparatus to operate normally, optical characteristics such as a focal position of the focused light irradiated onto the optical medium, the size of the focused light, the irradiation angle, and the like must meet predetermined criteria. Accordingly, various techniques have been proposed for determining whether such focused light is properly irradiated onto an optical medium.

However, the conventional technique for analyzing the characteristics of the focused light is to acquire an image to which the focused light is irradiated in the side direction of the optical medium, or to obtain an image to which the focused light is irradiated from the rear side of the optical medium to analyze it Therefore, it is difficult to accurately grasp the state in which the focused light is irradiated onto the optical medium.

The present invention is to solve the above problems, an optical information processing apparatus capable of accurately measuring the pattern information of the focused light by detecting a pattern in which the focused light is irradiated on the optical medium in the direction in which the focused light is irradiated to the optical medium And to provide a control method thereof.

The above object of the present invention is to provide a light source for irradiating light, an optical modulator for modulating the light irradiated from the light source, an optical system for condensing the light modulated by the light modulator and entering the optical medium, the optical medium is located And a control unit for controlling a position of the optical system or the stage by analyzing a pattern of the light detected by the light detection unit, and a stage for detecting a pattern of light reflected by the optical medium. Can be achieved.

Herein, the light detector detects the pattern of the light at the first position and the second position, respectively, and the controller compares the position, the size, or the distribution of the pattern of the light at the first position with the pattern of the light at the second position. The position of the optical system or the stage is controlled, and the second position refers to a position where the position of the optical system is moved by a predetermined interval or the position of the stage is moved by a predetermined interval compared to the first position. For example, the position of the stage may be spaced apart from the first position by a predetermined interval in the direction of light travel.

The controller may determine that the optical axis direction alignment of the stage coincides when the pattern of the light at the first position detected by the light detector and the center of the pattern of the light at the second position coincide with each other. And, by analyzing the position of the center of the pattern of the light at the first position and the pattern of the light of the second position detected by the light detector, the position change amount of the predetermined feature point in each pattern, and whether the stage is tilted It is also possible to judge.

On the other hand, it may further include a first position adjusting unit for controlling the position of at least one of the plurality of optical elements constituting the optical system and a second position adjusting unit for adjusting the inclination angle of the stage.

The controller controls the first position adjusting unit and the second position adjusting unit to control at least one of a focus position, a spot size, an irradiation angle, or an intensity distribution of light irradiated onto the optical medium. can do.

Here, the light incident from the light source is reflected in the direction of the light conversion unit, the light incident from the light conversion unit passes through the first beam splitter and the light incident to the optical medium to pass in the direction of the optical system and the optical The light reflected from the medium and incident may further include a second beam splitter that reflects the light toward the light detector.

Meanwhile, an object of the present invention described above is a light irradiation step of irradiating light modulated through an optical modulator to an optical medium through an optical system, a light pattern detection step of detecting a pattern of light reflected from the optical medium, and the light pattern detection step It may be achieved by a control method of the optical information processing apparatus including an analysis step of analyzing a pattern of light detected in the step, a position adjusting step of adjusting the position of the optical system or the optical medium in accordance with the information analyzed in the analysis step. .

Wherein the optical patum detection step includes a first detection step of detecting a pattern of light reflected from the optical medium at a first position and a second detection step of detecting a pattern of light reflected from the optical medium at a second position; The first position and the second position may be different from one of the optical system or the optical medium.

As an example, the second detection step may be located by moving the optical medium by a predetermined interval in the advancing direction of light compared to the first detection step.

In the analyzing step, when the center of the pattern detected in the first detection step and the pattern detected in the second detection step coincide with each other, the optical axis direction alignment of the optical medium may be determined to match.

In the analyzing step, the tilting of the optical medium is performed by analyzing a position change of each center position or a predetermined feature point in the pattern detected in the first detection step and the pattern detected in the second detection step. It is also possible to judge whether or not.

Further, the position adjusting step may control at least one of a focus position, a spot size, an irradiation angle, or an intensity distribution of the light irradiated onto the optical medium by adjusting the position of the optical system or the optical medium. have.

Here, the position adjusting step may control the position of at least one of the plurality of optical elements constituting the optical system or adjust the inclination angle of the stage on which the optical medium is located based on the information obtained in the analyzing step.

According to the present invention, since the pattern of the focused light can be measured on the optical medium in the direction in which the focused light is irradiated, accurate information can be obtained.

Further, by adjusting the position of each component of the optical information processing apparatus using the measured pattern information of the focused light, it is possible to minimize the error operation.

1 is a block diagram showing the configuration of an optical information processing apparatus according to an embodiment of the present invention;

FIG. 2 is a block diagram illustrating an example in which light is irradiated on an optical medium when the optical medium is moved in FIG. 1;

3 is a plan view illustrating a pattern of light detected through the light detector at each position of FIG. 2;

4 is a block diagram illustrating another example in which light is irradiated onto the optical medium when the optical medium is moved in FIG. 1;

5 is a plan view illustrating a pattern of light detected through the light detector at each position of FIG. 4;

6 is a plan view illustrating a light pattern according to a wavelength in FIG. 1;

7 is a plan view showing a state in which the reference light is irradiated in FIG.

FIG. 8 is a cross-sectional view illustrating a cross section irradiated to an optical medium and an irradiation cross section of the reference light in FIG. 7;

9 is a flowchart showing a control method of the optical information processing apparatus according to the present embodiment,

10 is a flowchart showing an additional control method of the optical information processing apparatus according to the present embodiment.

Hereinafter, an optical information processing apparatus and a control method thereof according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings. In the following description, the positional relationship of each component is explained based on the drawings in principle. In addition, the drawings may be displayed by simplifying the structure of the invention or by exaggerating if necessary for the convenience of description. Therefore, the present invention is not limited thereto, and various other devices may be added, modified or omitted.

In the present embodiment, a holographic optical information processing apparatus capable of recording information on an optical medium on which information is recorded is described as an example. However, the present invention is not limited thereto, and the information on the optical medium is reproduced by irradiating light. It is noted above that the present invention can be applied to various optical information processing devices including the device.

1 is a block diagram showing the configuration of an optical information processing apparatus according to an embodiment of the present invention. As shown in FIG. 1, the optical information processing apparatus 1 according to the present exemplary embodiment includes a light source 10, an optical modulator 20 that modulates light incident from the light source, and condenses the modulated light toward an optical medium. The optical system 30, the stage 40 on which the optical medium M is located, the optical detector 50 for detecting the pattern of the light reflected from the optical medium, and the pattern of the detected light are analyzed to determine the position of the optical system or the optical medium. It is configured to include a control unit 60 for controlling, hereinafter will be described in detail with respect to each component with reference to the drawings.

The light source 10 generates light used for recording information on the optical medium M or reproducing the information. The light source 10 may use light having coherent characteristics, such as a laser. The light source 10 may be configured to generate one monochromatic light according to an embodiment, but in the present embodiment, the light source 10 may be configured to generate a plurality of lights having different wavelengths. Specifically, in the present embodiment, a red laser having a wavelength of 635 to 660 nm, a green laser having a wavelength of 525 to 540 nm, and a red laser having a wavelength of 420 to 473 nm are generated. It is configured to be.

Light generated by the light source 10 is reflected by the first polarizing beam splitter (PBS) 31 and is incident to the light modulator. Here, the first beam splitter 31 has an optical characteristic that reflects light having a polarization characteristic of S wave and passes light having a polarization characteristic of P wave. Therefore, although not specifically illustrated in FIG. 1, the light generated by the light source 10 is converted into the S-wave form by using an optical element such as a half-wave plate (not shown), and then, the first polarized beam splitter 31. You can investigate.

In this way, the light generated from the light source is irradiated to the light modulator 20. In this case, the optical modulator 20 is configured to modulate incident light, and in the present exemplary embodiment, the optical modulator 20 may be configured using a liquid crystal on silicon (LCoS). Therefore, when the light modulator 20 is normally driven, the polarization characteristics of the incident polarization may be changed and reflected. In the present embodiment, the light incident from the light source 10 is reflected by the light modulator 20 and the polarization characteristic is changed from S wave to P wave.

The light modulator of the present embodiment uses a structure that reflects incident light, but this is an example and may be configured using a transmission type light modulator that modulates light while transmitting incident light. In addition, when the optical modulator is used in an apparatus for recording predetermined information on an optical medium, the optical modulator may be configured to include information to be recorded on light incident from a light source and to irradiate the optical medium in the direction of the optical medium.

Meanwhile, the light reflected from the light modulator 20 travels in the direction of the first polarization beam splitter 31 and the second polarization beam splitter 32 again. Here, the second polarizing beam splitter 32 has a property of passing P waves and reflecting S waves similarly to the first polarizing beam splitter 31. Accordingly, the light modulated by the light modulator 20 into the P wave passes through the first polarization beam splitter 31 and the second polarization beam splitter 32 and is incident in the direction of the optical system 30.

Here, the optical system 30 may form a path through which light travels, and may include a plurality of optical elements disposed in the optical axis direction. The plurality of optical elements may be configured to collect light incident from the light modulator 20, so that light passing through the optical system 30 may be irradiated on the optical medium M in a focused state.

The optical system 30 may be installed to move at least one of the optical system as a whole or a plurality of optical elements constituting the optical system to adjust the focal length, the irradiation area, and the distribution of light irradiated on the optical medium M. FIG. Can be.

In detail, the optical information processing apparatus 1 according to the present exemplary embodiment may include an optical system or a first position adjusting unit 70 capable of adjusting the position of at least one of the plurality of optical elements configuring the optical system. The first position adjusting unit 70 may be configured as a separate component that is installed adjacent to the optical system, or may be a component installed in the optical system. Therefore, the first position adjusting unit 70 changes the characteristics of the light irradiated onto the optical medium M by controlling the position of the whole optical system or a part of the optical elements constituting the optical system by the control signal of the control unit 60. You can.

On the other hand, the stage 40 is configured to position the optical medium (M), it is disposed on the other side of the optical modulator 20 on the basis of the optical system (30). The stage 40 may be configured in various forms according to the type of the optical medium (M) and the irradiation direction of light, and a detailed description thereof will be omitted. Accordingly, the optical medium M is positioned by the stage 40, and the light focused through the optical system 30 is irradiated onto the optical medium M to record information or to be reflected on the optical medium M. It is possible to acquire previously stored information.

On the other hand, the optical information processing device 1 according to the present embodiment may further include a second position adjusting unit 80 that can adjust the position of the optical medium (M) located on the stage (40). The second position adjusting unit 80 may be configured as a separate component that is installed adjacent to the stage, or may be a structure that is installed in the stage. The second position adjusting unit 80 may move the optical medium M in the horizontal or vertical direction or adjust the inclination of the optical medium M installed in the stage 40. Accordingly, the second position adjusting unit 80 may control the position or tilt of the optical medium M by the control signal of the control unit 60.

On the other hand, the light collected and irradiated in the direction of the optical medium (M) is reflected on the optical medium (M). In this case, the reflected light does not maintain polarization characteristics due to diffuse reflection on the optical medium, and thus may include both light having P wave characteristics and light having S wave characteristics.

The light reflected on the optical medium M travels in the opposite direction to the light path that was incident in the optical medium M direction. Accordingly, the reflected light reaches the second polarization beam splitter 32 with the focused state released while passing through the optical system 30 again. Among them, the light having the S-wave characteristic may be reflected by the second polarization beam splitter 32 and irradiated to the light detector 50 provided at one side.

The light detector 50 is configured to detect light reflected from the optical medium M, and may be configured as an imaging device such as a charged coupled device (CCD) or a complementary metal-oxide semiconductor (CMOS). Therefore, the light detector 50 can detect the pattern of light reflected from the optical medium M by detecting light formed on the surface of the CCD or CMOS. Here, the pattern of light means that the reflected light is formed in the light detector 50 and may exhibit various characteristics according to the position, shape, size and distribution of light. Accordingly, by detecting the pattern of the light reflected from the optical medium M, the light detector 50 can determine how the focused light is irradiated onto the optical medium.

Accordingly, the controller 60 analyzes the pattern of the light detected by the light detector 50, analyzes whether the light is normally irradiated onto the optical medium M, and according to the analyzed content, the first position controller 70 and By adjusting the position of the optical system 30 or the optical medium M by using the second position adjusting unit 80, it is possible to control so that light is normally irradiated onto the optical medium.

Hereinafter, an example in which the controller controls the light pattern detected by the photo detector will be described in detail with reference to FIGS. 2 to 8.

As described above, the controller 60 analyzes the characteristics of the light irradiated onto the optical medium M using the pattern of the light detected by the light detector 50. Here, the light detector 50 may detect a pattern of reflected light in the state where the optical medium M is positioned at different positions. Then, the controller 60 uses the plurality of light patterns detected in this manner to characterize the light irradiated onto the optical medium M, more specifically, the focus position, the spot size, the irradiation angle of the light, or the intensity of the light. Analyze information about distribution, etc.

In particular, when the optical medium M moves in the vertical direction along the optical axis direction (vertical direction as shown in FIG. 1), information such as the focal position of the light passing through the optical system and the tilt of the optical medium is analyzed by analyzing the pattern of light before and after the movement. It is possible to confirm.

FIG. 2 is a view illustrating an example in which light is irradiated onto an optical medium when the optical medium is moved in FIG. 1, and FIG. 3 is a plan view illustrating a pattern of light detected through the light detector at each position of FIG. 2.

2A illustrates a state in which the optical medium M is positioned at the first position. As shown in FIG. 2A, the optical medium M is inclined by a predetermined angle θ. Therefore, even when light focused in the vertical direction is incident, the light reflected by the optical medium proceeds obliquely by a predetermined angle 2θ in the vertical direction.

Accordingly, as shown in FIG. 3A, the light pattern formed on the surface of the light detector 50 is formed in a state in which the light pattern is biased in one direction from the center of the light detector 50. And, even in the case of irradiating circular light, as shown in a of FIG. 3, it is formed in the shape of an ellipse while extending in a specific direction.

2B illustrates a state in which the control unit 60 controls the second position adjusting unit 80 to move the optical medium M to the second position. In this case, the second position corresponds to a position spaced apart by a predetermined interval d along the optical axis direction (vertical direction) compared to the first position. Although the second position is located farther from the end of the optical system 30 in the present embodiment, this is an example and may be a position moved upward in a direction closer to the end of the optical system.

Even when the position of the optical medium M is moved as shown in b of FIG. 2, the inclination of the optical medium is kept the same. Therefore, when the light focused in the vertical direction is incident from the optical system 30, the reflected light proceeds obliquely by 2θ from the vertical direction as in a of FIG. However, compared to a of FIG. 2, a path through which light travels between the optical medium M and the optical system 30 increases. Thus, as shown in b of FIG. 3, the light pattern formed in the light detector 50 has the same shape as the a pattern of FIG. 3 but is more oriented in one direction and is larger than the a pattern of FIG. 3. Has a pattern.

Therefore, the control unit 60 analyzes the first pattern (pattern a of FIG. 3) and the second pattern (b pattern of FIG. 3) obtained by the optical medium M at the first position, such that the optical medium M is tilted. You can see it's in the true state. In addition, by comparing the normal light pattern with the first pattern and the second pattern, the tilt direction and the tilt angle of the optical medium may be calculated (for example, when a circular light pattern is designed to detect a normal case, It is possible to calculate the inclination angle using the ratio of the long axis and short axis of one pattern or the second pattern). Accordingly, the controller 60 may control the second position adjusting unit 80 to position the optical medium M to maintain the direction perpendicular to the optical axis.

However, when the optical medium M is inclined, a light pattern having a shape extending in one direction compared to a normal light pattern is detected by being biased in one direction from the center of the light detector 50. Therefore, even when the patterns obtained at the two positions are not compared as described above, the inclination of the optical medium may be expected, but it may be unclear whether such a phenomenon is caused by the position defect of the optical system or the position defect of the optical medium. have. Therefore, it may be more accurate to analyze the alignment state using a plurality of light patterns detected at different positions as described above.

Meanwhile, FIG. 4 is another example illustrating a state in which light is irradiated on the optical medium when the optical medium moves in FIG. 1, and FIG. 5 is a plan view illustrating a pattern of light detected through the light detector at each position of FIG. 4.

4A illustrates a state where the optical medium M is positioned at the first position, and FIG. 4B illustrates a state where the optical medium M is positioned at the second position. 4, the optical medium M is not inclined as compared with FIG. 2, and is positioned horizontally in a direction perpendicular to the optical axis.

Therefore, as shown in FIG. 5A, the light pattern with the optical medium M positioned at the first position is circularly detected at the center of the light detector 50. As shown in b of FIG. 5, the optical pattern of the optical medium M in the second position is circularly detected at the center of the light detector 50, and is enlarged compared to a of FIG. 5. Can be detected.

Therefore, the controller analyzes the first pattern (a of FIG. 5) and the second pattern (b of FIG. 5), and when the two patterns have the same shape and center position and only different sizes, the horizontality and the optical system of the optical medium. It can be determined that the alignment of the optical axis direction is normally performed, and the focus position and the spot size can be controlled.

Here, the control of the focus position and the spot size may be performed in a manner that matches the size of the preset light pattern with the light pattern detected by the photo detector. To this end, the controller 60 controls the first position adjusting unit 70 to move the position (eg, the objective lens) of some optical elements of the optical system in the optical axis direction, or the second position adjusting unit 80. By controlling the position of the optical medium (M) can be moved in the vertical direction. When the light pattern acquired at each position coincides with the preset light pattern, it is possible to grasp the state where the focus position and the spot size coincide to complete the setting.

As described above, according to the present exemplary embodiment, the controller 60 may align the positions of the optical system and the optical medium by using the information of the light pattern obtained from the light detector 50. However, although only some application examples have been described above, light information may be obtained by using information on the position of the light pattern (the position of the center or the feature points such as the major axis and the minor axis), the size, the shape, and the intensity distribution of the light obtained by the light detection unit. Not only the focus position and the spot size, but also the irradiation angle and the light intensity distribution can be variously corrected.

Hereinafter, a usage example according to the present embodiment will be described with reference to FIGS. 6 to 8.

First, FIG. 6 is a plan view illustrating a light pattern according to a wavelength in FIG. 1. As described above, the light source according to the present embodiment may be configured to irradiate light of various wavelengths. However, since some optical elements constituting the optical system have different aberrations depending on the wavelength of the traveling light, even when the optical system and the optical medium are in the same position, the light pattern detected by the light detection unit differs depending on the wavelength of light emitted from the light source. can do.

6A is a light pattern obtained by the light detector 50 when the red laser is irradiated, b of FIG. 6 is a light pattern obtained by the light detector 50 when the green laser is irradiated, and FIG. When irradiated, the light pattern may be a light pattern obtained by the light detector 50.

As such, even if the same optical path is performed, errors of a predetermined interval may occur in the light pattern detected according to the wavelength of light. Therefore, in this case, the controller 60 may calculate the correction value according to the wavelength by analyzing the light pattern according to the wavelength of each light. For example, it may be calculated as (x1, y1) for a red laser, (x2, y2) for a green laser, and (x3, y3) for a blue laser.

Therefore, the control unit 60 stores the correction value for each wavelength of the light, and then selectively controls the position of a part of the optical element constituting the optical system 30 according to the wavelength of the light irradiated from the light source, thereby reducing the amount of light irradiated from the light source. It is possible to minimize the errors that can be caused by the wavelength.

7 is a plan view illustrating a state in which the reference light is irradiated in FIG. 1, and FIG. 8 is a cross-sectional view illustrating a cross section of the irradiation light of the reference light and an optical medium in FIG. 7.

As shown in FIG. 7, the optical information processing apparatus 1 according to the present embodiment may further include a reference light irradiator 90 for irradiating reference light. In an optical medium such as a holographic storage medium, information is recorded by an interference phenomenon of light, wherein the reference light is irradiated to the optical medium M at a predetermined irradiation angle with the light irradiated from the light source.

In this case, in the case of the optical medium to which the angle multiplexing method is applied, different information may be recorded or reproduced at the same position according to the angle at which the reference light is irradiated, and even when the angle multiplexing method is not applied, The intensity may be different. Therefore, in order to operate the optical information processing apparatus normally, the reference light should be irradiated to the optical medium at a predetermined irradiation angle, and the optical information processing apparatus according to the present embodiment uses the reference light pattern formed in the light detector 50 to reference the optical medium. It is possible to analyze and correct the irradiation angle of the light.

FIG. 8 is a view illustrating a cross section of the reference light and a light pattern detected by the reference light on plane A in FIG. 7. When the reference light is irradiated onto the optical medium M, diffuse reflection occurs on the optical medium M, and a portion of the reference light reaches the light detector 50 through the optical system 30. Therefore, when the reference light is irradiated, it is possible to calculate the irradiation angle of the reference light using the light pattern detected by the light detector 50.

When the reference light has a circular cross section (left side of a in FIG. 8) and is irradiated to the optical medium at an angle as shown in FIG. 8A, the light pattern detected by the light detecting unit 50 has an elliptic shape (right side in a of FIG. 8). Is detected. Thus, similar to that described with reference to FIG. 3, the light pattern is configured to have a shape extending in a predetermined direction according to the irradiation angle of light. Therefore, it is possible to determine whether the reference light is normally irradiated at the irradiation angle by using the ratio of the long axis d2 and the short axis d1 of the ellipse.

8A illustrates an example in which the reference light is irradiated in a circular cross section, but even when the reference light has a specific cross section as shown in FIGS. 8B and 8C, the ratio of the long axis and the short axis of the light pattern is referred to. It is possible to calculate the irradiation angle of the reference light.

Therefore, the controller 60 analyzes the detected light pattern to calculate the irradiation angle of the reference light, and then, when the irradiation angle is different from the preset angle, the control unit 60 uses the third position adjusting unit (not shown) to operate the reference light irradiation unit 90. By controlling, it is possible to correct the irradiation angle.

As described above, the present embodiment can automatically control not only the alignment of the optical medium and the optical system, but also the error correction and the irradiation angle of the reference light according to the wavelength of light. have.

Hereinafter, a method of controlling the optical information processing apparatus according to the present embodiment will be described with reference to FIGS. 9 and 10. First, FIG. 9 is a flowchart showing a control method of the optical information processing apparatus according to the present embodiment.

First, in a state where the optical medium M is positioned at the first position, the step of irradiating the first light by driving the light source 10 is performed (S10). In this case, the light irradiated from the light source 10 may be light for recording information on the optical medium M, or may be separate alignment light for measuring the alignment state of the optical system or the optical medium.

The first light irradiated from the light source 10 is reflected on the optical medium M and is incident on the light detector 50, and the light detector 50 detects the first light pattern formed on the surface by the first light. (S20).

In addition, the controller 60 controls the second position adjusting unit 80 to move the optical medium M to the second position, and then irradiates the second light (S30). In this case, as described above, the second position corresponds to a position spaced at a predetermined interval in the vertical direction compared to the first position. The second light uses light having the same characteristics as the first light.

Like the first light, the second light is reflected on the optical medium and is incident to the light detector 50, and the light detector 50 detects the second light pattern formed on the surface by the second light (S40).

However, in the control method, the light irradiated from the light source is divided into the first light and the second light, and the light is intermittently irradiated according to the position of the optical medium. However, the present invention is not limited thereto. The optical medium moves in a state where light is continuously irradiated, and the light detector may be configured to selectively detect the first pattern and the second pattern.

As such, when the first light pattern and the second light pattern are detected, the controller 60 compares the two patterns to determine whether the optical medium M is tilted (S50). If it is determined that the positions of the centers of the two light patterns are at the same position, it is determined that the optical medium M is kept horizontal. However, when it is determined that the optical medium M is inclined by a predetermined angle, the second position adjusting unit 80 is controlled to correct the inclination of the optical medium M (S60). Determine the correct slope correction by obtaining.

If it is determined that the optical medium M is horizontal, the controller 60 controls the focus position while controlling the first position adjusting unit 70 or the second position adjusting unit 80. After one (S70) can be finished.

10 is a flowchart showing an additional control method of the optical information processing apparatus according to the present embodiment. In FIG. 9, the method of adjusting the inclination and the focus position of the optical medium using the light pattern is described. In addition, as shown in FIG. 10, the light pattern is analyzed to calculate a correction value according to the wavelength. It is also possible to additionally perform the step of controlling the irradiation angle of the reference light.

For example, after the step of adjusting the focus position (S70) is completed, the light source irradiates the red laser (S81), detects the light pattern, calculates the correction coordinates according to the red wavelength band, and stores it (S82). The light source irradiates the green laser again (S83), and then calculates and stores correction coordinates according to the green wavelength band in the same manner (S84). Further, the light source irradiates the blue laser again (S85), and then calculates and stores correction coordinates according to the blue wavelength band in the same manner (S86).

Therefore, the controller 60 controls the position of the optical system 30 by considering the correction coordinates according to the wavelength of light generated by the light source when the optical information processing apparatus 1 is driven, using the calculated correction coordinates for each wavelength. It is possible to minimize the error due to the wavelength.

On the other hand, when the step of calculating the correction coordinates according to the wavelength is finished, the step of aligning the irradiation angle of the reference light can be further proceeded. To this end, the reference light irradiator 90 irradiates the reference light with the optical medium (S91). In addition, the light detector 50 detects a light pattern formed by the reference light transmitted from the optical medium M. Then, the controller 60 analyzes the irradiation angle of the reference light by using the detected light pattern, and determines whether or not it corresponds to the preset irradiation angle (S92). If the irradiation angle of the reference light is different from the preset irradiation angle, the irradiation angle of the reference light is adjusted by controlling the third position adjusting unit (S93). Further, by repeating the step of irradiating the reference light again and analyzing the light pattern to determine whether the irradiation angle of the reference light corresponds to the preset angle, it is possible to accurately align the irradiation angle of the reference light.

As described above, in the case of the optical information processing apparatus according to the present embodiment, the installation state of the optical medium, the alignment state of the optical system, the alignment state of the reference light irradiator, etc. are automatically detected using the light pattern acquired by the light detection unit. By automatically adjusting and optimizing this, it is possible to minimize the occurrence of an error when the optical information processing apparatus is driven.

However, FIGS. 9 and 10 merely illustrate an example of controlling the optical information processing apparatus using the present invention, and of course, the present invention may be modified in various ways using the technical idea of the present invention. .

Claims (19)

1. A light source for irradiating light;

   An optical modulator for modulating light emitted from the light source;

   An optical system for condensing light modulated by the light modulator and incident the light on the optical medium;

   A stage on which the optical medium is located;

   A light detector detecting a pattern of light reflected from the optical medium; And,

   And a controller configured to control the position of the optical system or the stage by analyzing the pattern of the light detected by the light detector.
2. The method of claim 1,

   The light detector detects the pattern of the light at the first position and the second position, respectively, and the controller compares the position, the magnitude, or the intensity distribution of the pattern of the light at the first position with the pattern of the light at the second position. To control the position of the optical system or the stage,

   And the first position and the second position are different from each other in the position of the optical system or the position of the stage.
3. The method of claim 2,

   And the second position is a position spaced apart from the first position by a predetermined interval in the optical axis direction.
4. The method of claim 3,

   The control unit determines that the optical axis direction alignment of the stage coincides when the pattern of the light at the first position detected by the light detector and the center of the pattern of the light at the second position coincide with each other. Device.
5. The method of claim 3,

   The controller analyzes the position of the center of the pattern of the light at the first position and the pattern of the light of the second position detected by the light detector, and the position change amount of a predetermined feature point in each pattern, thereby tilting the stage. An optical information processing apparatus, characterized in that determining whether or not.
6. The method of claim 2,

   And a first position adjusting unit capable of controlling the position of at least one of the plurality of optical elements constituting the optical system, and a second position adjusting unit capable of adjusting the inclination angle of the stage.
7. The method of claim 6,

   The controller controls the first position adjusting unit and the second position adjusting unit to control at least one of a focus position, a spot size, an irradiation angle, or an intensity distribution of light irradiated to the optical medium. An optical information processing apparatus characterized by the above-mentioned.
8. The method of claim 3,

   The light incident from the light source is reflected in the direction of the light conversion unit, and the light incident from the light conversion unit passes in the direction of the optical system and the first polarizing beam splitter and the light incident to the optical medium passes through the optical medium And a second polarizing beam splitter which reflects light incident from the incident light toward the light detector.
9. The method of claim 1,

   The light source is configured to generate at least two lights having different wavelengths, and the controller calculates correction coordinates according to each wavelength by analyzing each light pattern detected by the light detector by light of each wavelength. An optical information processing apparatus, characterized in that.
10. The method of claim 1,

    And a reference light irradiation unit for irradiating the reference light with the optical medium, wherein the controller calculates an irradiation angle of the reference light by using a shape of the light pattern formed by the reference light.
11. A light irradiation step of irradiating light modulated through the optical modulator to the optical medium through an optical system;

    A light pattern detecting step of detecting a pattern of light reflected from the optical medium;

    An analysis step of analyzing a pattern of light detected in the light pattern detection step;

    And a position adjusting step of adjusting the position of the optical system or the optical medium in accordance with the information analyzed in the analyzing step.
12. The method of claim 11, wherein the detecting of the light pattern is performed.

    A first detecting step of detecting a pattern of light reflected from the optical medium at a first position and a second detecting step of detecting a pattern of light reflected from the optical medium at a second position,

    And the first position and the second position are different from each other in the position of the optical system or the optical medium.
13. The method of claim 12,

    The second detection step is a control method of the optical information processing apparatus, characterized in that the optical medium is moved by a predetermined interval in the travel direction of the light compared to the first detection step.
14. The method of claim 12,

    In the analyzing step, when the center of the pattern detected in the first detection step and the pattern detected in the second detection step coincide, the optical axis direction alignment of the optical medium is determined to match. Control method
15. The method of claim 12,

    The analyzing step analyzes the position of each center in the pattern detected in the first detection step and the pattern detected in the second detection step or the position change amount of a predetermined feature point to determine whether the optical medium is tilted. The control method of the optical information processing apparatus, characterized in that the judging.
16. The method of claim 12,

    The position adjusting step may include adjusting the position of the optical system or the optical medium to control at least one of a focus position, a spot size, an irradiation angle, or an intensity distribution of light irradiated onto the optical medium. A control method of an optical information processing apparatus.
17. The method of claim 16,

    The position adjusting step includes controlling the position of at least one of the plurality of optical elements constituting the optical system based on the information obtained in the analyzing step, or adjusting the inclination angle of the stage on which the optical medium is located. Control method of processing device.
18. The method of claim 11,

    The light irradiation step sequentially irradiates light of different wavelengths,

    The optical pattern detecting step detects each optical pattern formed by the light of each wavelength,

    And said analyzing step calculates correction coordinates according to the wavelength.
19. The method of claim 11,

    Irradiating a reference light to the optical medium by driving a reference light irradiator;

    Detecting a reference light pattern formed on a light detector by the reference light; And

    And calculating an irradiation angle of the reference light by using the reference light pattern.

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