TW200832388A - A system and method for determining the position of a plurality of laser spots on an optical disc - Google Patents

Abstract

A system for determining an angular measure (AM) of a plurality of spots intended to be applied to an optical disc, with respect to said optical disc, said system comprising: -a detecting unit for detecting light signals derived from said plurality of spots, said detecting unit comprising a set of detectors aligned according to a same direction D, each of said detectors being intended to receive one light signal derived from one spot of said plurality of spots, each of said detectors having a first light-sensitive area and a second light-sensitive area positioned on both sides of said direction D; a first output signal (OS1A; OS1B) being derived from said first light-sensitive area and a second output signal (OS2A; OS2B) being derived from said second light- sensitive area and -a generating unit (320) comprising: (a) a first module (320) for generating, for each of said detectors, a set of first offset signals by calculating, the difference between said first output signal (OS1A; OS1B) and said second output signal (OS2A; OS2B); (b) a second module for generating a set of second offset signals by calculating the difference of each pair of first offset signals; and c a third module for determining said angular measure (AM) according to said set of second offset signals.

Description

200832388 IX. DESCRIPTION OF THE INVENTION: TECHNICAL FIELD OF THE INVENTION The present invention relates to a system and method for determining the position of a plurality of laser points on a compact disc, and more particularly, a method for determining A system and method for measuring the angle of a plurality of laser spots on a disc. [Prior Art] In an optical storage drive, it is necessary to precisely control the position of the dots on the optical disc. For a single point drive, the radial actuator of the objective lens is in charge of this control. In the case of multiple points, both radial and rotational motion must be controlled. Therefore, an additional so-called angle actuator is needed for rotating the laser spot on the optical storage disc. Not only is this angle actuator required to ensure that all points are tied to the track, but it also needs to have the possibility of an advanced jumping strategy (i.e., various displacements of points on the disc). There is a method of generating an angular error signal from the difference between the radial push-pull error signals from two points (push-pull method). The control scheme includes converting a plurality of radial tracking signals into a radial error signal and a rotational error signal to the y module and converting the radial error signal and the rotational error signal into a radial actuator input and a rotation Actuator input one of the controller modules. The rotation error signal can also be referred to as an angular error signal. Therefore, a radial actuator will obtain an edge-actuated input and control the radial movement of the two points through a servo loop, and the angle actuator will use the angular error signal to control two through a servo loop. An angular movement of points. Therefore, the two points can be held on the magnet. This push-pull method can also be applied to situations where more than two points have been involved. H8361.doc 200832388

It may happen that a plurality of points must be shifted along a relatively long distance on a disc, such as a jump in finding a piece of material stored on the disc. In such motions, the point travel on a plurality of magnetic handles, and the actual angular position of the points cannot be indicated using a push-pull method. Indeed, the push-pull method only allows for angular errors when the points are slightly off-track, and after a relatively long-distance jump, they do not function properly due to their periodic characteristics. For example, in the case where the optical discs happen to be on the magnetic track (for example, in the case of A, B or C in Fig. 1, it displays 3 points of a set of tracks of the comparative optical disc continuously positioned at different angles)" by using The output signal of the push-pull method is the same, meaning that it cannot indicate the angle of the three points with respect to the tangent of the optical track: Therefore, the angle information will be lost after a jump. SUMMARY OF THE INVENTION One object of the present invention is to provide a system and method for determining the angular measurement of a plurality of points relative to a disc. To this end, a system for determining an angle measurement for application to a disc relative to the disc is presented, the system comprising . Debt test saponin, which is used for debt measurement from the plurality of points, the detection unit includes a set of benefits according to the direction of the relative direction D, each of the detectors of the detectors , , , / / 敦夕. You are used to receive one from the complex |

The optical signal from the point V of the μ, the detection of J 5 | H from the ancient * warrior 丄 1 beta measurement of the mother of a detector 4 2, there is a _ photosensitive in the direction of the 〇 Zone 2, 200832388 a) One brother and one twist group, which is used for each detector of the look-ahead beta detector, by calculating the first output signal Jin Chu Chu - /, ° Hai first round The difference between the signals is generated to generate a set of first offset signals; b) - a second module for use by arsenic. Deriving a difference between the first offset signals to generate a set of second offset signals; and c) a third module for determining the angle measurement according to the far-distance offset signal .

A method has also been proposed, the JL package and the Gushan a #^ 八b 3, having the functional steps defined by the features of the system according to the invention. The angle measurement is determined by using a fixed relationship between the second offset signal and the angle measurement. This and other aspects of the present invention will be described and understood by reference to the <RTIgt; [Embodiment] The technical measurement of the present invention will be described in detail below with reference to the drawings. Figure 2 illustrates one of three points on different planes and one of the output signals obtained therefrom, in accordance with an embodiment of the present invention. The first line shows the three points (A, B, C) on the disc at different angles to the track. 〇 The first line indicates that the laser points land on the corresponding tracks on the information plane of the disc. After the laser is reflected by the surface of the disc, each beam is directed by an optical path to its corresponding photon detector, which converts the intensity signal from the laser beam into an electrical signal. 118361.doc 200832388 The first line shows these two points (A, B, C) in the detector plane with the same angle as on the disc. Each detection system is further divided into two quadrants. The laser beam that is landed on the detector is shown in line two. The electrical signal from the 裔 裔 象 quadrant is proportional to the beam intensity and the area of the beam landing on this quadrant. Therefore, the signal changes as the position of the laser beam landing position changes. The different angles of the beams will therefore have different angle measurements, as shown in row three. The angle of the points relative to the tangential direction of the magnets can be obtained by subtracting the tangent signals at different points. These arrows show the center of rotation of the array of points. The third line shows the offset signal from the point +1 minus the corresponding offset signal of the point q. The method of obtaining the offset signal of each point is subtracted from the signal of the right partial detector by the left partial detector. signal. For example, the angle measurement AMI is measured between a line B interconnecting the plurality of points and a tangent T of the track of the optical disc, as shown in Fig. 2 (α, β). Figure 3 illustrates a system 300 for determining A% of a plurality of points for application to a disc relative to an angle of the disc in accordance with an embodiment of the present invention. For the sake of understanding, the present invention is illustrated using only three points, but similar interpretations apply to a higher number of points or only two points. The present invention provides a system that includes: a detection unit 310 for detecting (also corresponding to a detection step) an optical signal derived from the plurality of points? 'The detection unit 310 includes the same direction according to 〇 Aligned set of detectors A, B, C, each of the detectors A, b, c of the detectors are each receiving 118361.doc 200832388 - light derived from one of the plurality of points Signal, material: each of the detectors has a first light positioned on both sides of the direction: the left part of each detector as shown in FIG. 3) and the second light (four). Each of the - (four) devices are right part); - the first: (for example, '〇~ and 〇SlB) are derived from the first photosensitive region, and a tiger output signal (for example, os2a and 0S2B) B) is the U brother - the photosensitive area is derived. Love B, C can also be a traditional four-quadrant predator. Here, each of the &#;white... and second photosensitive areas contains two quadrants. The signals from the two quadrants are summed to form the first pass or the second output. °: The debt detectors A, B, and C are aligned in the same direction d, and the directions D and 2. are in the tangential direction of the track on the first disk. The direction does not span the respective center points of each of the probes, but preferably spans the center of gravity of the set of detectors. The system also includes a generating unit, and the generating unit 32 includes a module 321 'for each detector of the detectors, # is calculated by calculating a difference between the first output signal and the second output signal (in response to a generating step) Group the first offset signal. The first module 321 can, for example, include a set of subtractors ~ and ^. The subtractor obtains the inputs 〇S1 八 and 0S2a from the pain detector eight and calculates the difference (OS2a_os1 a) as the first offset signal; likewise the subtractor Sb obtains the inputs 〇siB and 〇§2β from the detector B and calculates the difference (OS2b - 〇 S1b) as the first offset signal. The generating unit 320 further includes a second module 322 for generating (also corresponding to a generating step) a set of 118361.doc 200832388 second offset signals by calculating a difference between each pair of first offset signals. The second module 322 can, for example, be a packet switcher. In Fig. 3, 徭_u, subtraction and switching s/ and two knives around the subtractor s: the subtractor s obtains a pair of first signals (eg from the subtractor:: shift signal and from the subtractor) The first offset signal of %) ((10)(10)b-〇S1b) is the second offset. In this case, the two switches SWa and SWb are switched to: from - similarly, other subtractors in the second module can produce different first offset signals. In the present invention, the second offset signal is also referred to as a tangent error signal. Figure 4. The relationship between the tangent error signal TE and the angle of the plurality of points - the angle between the line connecting the plurality of points and the tangent of the track of the optical disc. The curve is considered linear near the angle zero. When the angle is ~added, there will be a _saturation area. As the angle increases further, the point leaves the traverse, so the signal returns to zero. The working area used to have the correct tangential error signal is a linear region. Therefore, the second offset signal corresponds to a tangent displacement of a point, since the distance between the points is fixed, so the angle measurement can be determined. The generating unit 320 further includes a third module 323 for determining (also corresponding to a determining step) the angle measurement according to the set of first offset signals. The angle measurement am is determined by using a fixed relationship between the second offset signal and the angle measurement Α. One method of determining the angle measurement (AM) is by calculating (also corresponding to the different steps) the average of the set of second offset signals. Possible system presence 118361.doc 200832388 Multiple generated second offset signals 'In this case the third module (2) is used to calculate the average of the second set of offset signals in order to obtain a more accurate AM 〇

If the - point is being written 'while other points are being read, or when a point is landing on the - part of the disc, while other points are landing on the blank part of the disc (different reflectivity)' then reflect the light Large differences require normalization of the error signal. Considering this factor, the generating unit 32A further includes a normalization mode, and 324, which is used to normalize (also corresponds to a calculation step) the set of first offset signals to overcome the set of first offset signals. Different reflectivity. For example, as shown in FIG. 3, the normalization module 324 can include a set of adders (e.g., Aa and Ab) and a set of dividers (e.g., d^Db). OS1^〇S2a is fed into Aa, which then outputs the sum: 〇s1a+〇S2a. The divider Da takes OS1a + OS2a &amp; S2a-OS1a as an input and calculates an output (〇S2a - OS1a) / (OS1a + 〇 S2a). Since the signal 〇s1a+〇S2a reflects the overall light intensity of the detector a, the difference in light reflectance is compensated. In this case, the S WA switches to obtain an input from Da and s Wb to switch to obtain an input from the DB. There is a case where the angle measurement (AM) can be determined only by using two detectors, a first detector A and a second detector B. In this case, the generating unit generates the angle measurement (AM) according to the following formula: AM = K 7 (952, -051^ [057 广 {〇SlA^〇S2Aj {〇SlB^OS2B)_ Κ represents a parameter 〇S1A indicates that the first photosensitive signal generated by the first photosensitive region of the first detector (A) has a first output signal 'OS2A indicating 118361.doc generated by the second photosensitive region of the first detector (A). 12-200832388 A second output signal, 0S 1β represents a first output signal generated by the first photosensitive region of the second detector (B), and 0S2B represents a second photosensitive of the second detector (B) The region produces one of the second output signals. Based on the above formula of AM, the first module 321 includes a first subtractor sA and a second subtractor Sb. The heart and % respectively generate a first offset signal (OS2A-〇SlA) and (〇S2B-〇siB).

It should be noted that the first offset signals (0S2a-0S1a) and (0S2b-0S1b) can be directly input into the second module 322, and the second module 322 includes a subtractor S° subtractor S and then generates a first The second offset signal (〇S2a_〇s1a)_(〇S2b_ os ib) ' is proportional to am. In this case, sWa switches to get input from Da and SWB switches to get input from db. The processing module 324 is configured to normalize the first offset signals (〇S2a_〇s1a) and (OS2b-〇S 1B). The processing module 324 can include a first divider da, a first adder Aa, a second divider, and a second adder &amp; Aa produces the output signal (OS2a + 〇 s1a) which is fed into the heart. Ab generates the output signal (OS2B+OSlB), which is fed into db. DA and DB respectively produce output ##(0S2a-0S1a)/(0S2a+0S1a) and (〇S2b-〇S1b)/(〇S2b + 〇SlB) 〇(〇S2a^osiA {〇S1a^〇S2aJ [〇SlB ^〇S2BJ_ δ海弟一模块 322 may include a subtractor s and two switches swA and SWB. The switches SWA and SWB are switched to obtain inputs from da and DB, respectively, and then the subtractor S generates a second offset signal. It is proportional to the angle measurement (AM). 〇S2b - 052 J [〇SlB^OS2B)_ The second offset signal is transmitted to the 118138.doc -13- 200832388 two module 323 'last angle The measurement (AM) is generated according to the following formula: Γ 052^-051,] J, 051, + 052 J {〇SlB^OS2Bj^

AM = K Figure 5 illustrates a pattern of multiple points on the detector plane. The present invention is also applicable to the case where two or more points are used for the angle measurement. It is assumed that there are η+m+1 detectors in total (n, m is an integer greater than 〇). There is a randomly selected base detector, and there are n detection benefits on one side of the base detector (n is an integer greater than 〇), and there are m on the other side of the base detector Detector (m is an integer greater than 〇). The formula for providing this angle measurement is as follows:

AM n^m Σ:&amp; ^ R^Li Σ 7=o RJ^LJ c〇_ and . -A) dJ Rj^Lj dj ~F0+L0 In this equation, the formula and A respectively represent the distance from the H detector and the j detector to the base detective; c• and ~ are parameters; The first photosensitive area of the reader generates an output signal, and the expression represents a round-out signal generated by the second photosensitive area of the detector, as shown in FIG. In FIG. 5, the distance between the center of the detector and the center line of the detector is 0. The present invention also provides a system rb ^ ^ . A detector A and the second 4 贞 裔 B 定位 定位 定位 定位 定位 定位 接收 接收 接收 接收 接收 接收 接收 接收 接收 接收 接收 接收 接收 接收 接收 接收 接收 接收 接收 接收 接收 接收 接收 接收 接收 接收 接收 接收 接收 接收 接收 接收 接收 接收The detector A and the detector B are relative to the shape of the moon, and the obtained angle measurement is more accurate. Because in the case of the zero degree, the music is of the right and the poem has the right 118361.doc - 14- 200832388 The working area of the tangential signal is a linear area, so the system can include a unit (not shown) that limits the angle measurement (also corresponding to the - limiting step) within a predetermined range. The predetermined range is between 10. and 10. W is in - for playing/recording 1. The disc player/recorder can include a system as described above. For example, the player/recorder player/record The first disk first computer may also include a system as described above. The invention may also be used to determine a relative point for application to a point. The computer program product contains the instruction code for implementing the above steps in the production of the appropriate program computer program product at the corner of the optical disc, Δ λ Γ / Γ, ', the number of turns, angle measurement (ΑΜ). The present invention has been illustrated and described in detail in the drawings and the claims. From the drawings, the disclosure, and the accompanying patents, the scope of the patents, the inventions of the inventions may be understood and implemented in the practice of the invention. , the word contains "or &quot;includes&quot; does not exclude other components or steps, and the indefinite article &quot;one&quot;=&quot; does not exclude plural. - A single-processor or other unit can perform the functions of several items described in the scope of the patent application. Any reference signs in the scope of patent application should not be considered as limiting. [Simple description of the diagram] Figure 1 shows that the group compares the tracks of the disc to three points at different angles: 11836l.doc -15· 200832388. Figure 2 illustrates a diagram of one of the output signals obtained at no false point and obtained therefrom in accordance with an embodiment of the present invention. Figure 3 illustrates a system for measuring an angle of a point in accordance with an embodiment of the present invention. Figure 4 illustrates the relationship between the tangent error signal and a plurality of points.

The three on the same plane are used to determine the relationship between the complex angles. Similar or corresponding to the figure. Figure 5 illustrates the pattern of multiple points on the detector plane. In the above figures, the same reference number indicates the same, piece or function. . [Main component symbol description] 300 310 320 321 322 323 324 A Aa Ab AM BC 118361.doc System detection unit generation unit / first module first module second module brother three module normalization module point /First Detector First Adder Second Adder Angle Measurement Point / Second Detector Point / Detector-16 - 200832388

Da First Divider Db Second Divider S Subtractor SA First Subtractor Sb Second Subtractor SWa Switcher SWb Switcher -17- 118361.doc

Claims (1)

200832388 X. Applying for a patent Fan Park·· 1. A system (300) for determining an angle (AM) of a plurality of points for application to a disc relative to an optical disc, the system comprising: a detecting n unit (31G) for use in 彳贞Detecting the optical signal derived from the plurality of points, the detecting unit (310) includes a set of _ according to a pair of the same direction (D), and each of the detectors is used by each of the detectors And receiving: (four) optical signals from the plurality of points-points, each of the detectors of the (four) metrics each having a first photosensitive area and a second photosensitive position positioned on both sides of the direction (D) a region; the first output signal (OS1A; 〇S 1b) is derived from the second sensible region ... 〇 S2a; 〇 S2b is derived from the second photosensitive region; The unit (320) includes: a) a first module (321) for each of the detectors to be different by the first output signal (OS1A; 0S1b) a difference between the second output signals (os2a, os2b) to generate a set of first offset signals; b) a first module (322) 'for calculating each pair of first offset apostrophes Yilai A second set of raw offset signal; and C) a third module (323), which is used according to the set of second signals to determine the offset angle measurement (AM). 2. As requested! The system (32〇〇)&apos; the generating unit (32〇) further includes a processing module (324) for normalizing the set of first offset signals. 3. t request item or system 2 (300), wherein the third module (323) also averages the second offset signal of the palm juice group 6 hai group for determining the angle measurement 118361.doc 200832388 (ΑΛ4) ο 4. The system (300) of claim 1, wherein the group of price detectors includes a first detector (eight) and a second side device (8), wherein the first device (the half detector) The device (8) is a system for locating the received light signals at the plurality of points. The system (300) of claim 1, further comprising a unit for limiting the measurement (AM) within a predetermined range. The angle is 6. The system (3.〇) wherein the predetermined range is a method for determining a MW for a plurality of points applied to a disc relative to the optical disc, the method comprising the steps of: A single unit detects the optical signal derived from the plurality of points. The detection unit packs a group of debt detectors in the same direction. Each of the detectors of the group detects Wu Hao. The mother-in-laws are each used to receive an optical signal derived from the point-point of the plurality of points, each detector of the group of detectors Since there is a first photosensitive region and a second photosensitive region positioned on both sides of the direction (9), a first mountain &gt; i month 51 output (OS 1a; OS 1b) is derived from the first photosensitive region And the _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ A difference between the output signal (0S1) and the first-one round-out signal (0S2) to generate a set of first offset signals; the difference between the signals to generate a set of second offset signals by calculating each pair of _ No.; and 118361.doc 200832388 According to the group of the first - value # w + - partial private 4唬 to determine the angle measurement (AM) 〇. Kiss method 7 method, the method who + 勹人田έΒ m ^ 夭 violation of the package Each of them is used to normalize the steps of the offset signal. 9. If the request item 7 or 8 eve, + ^ ^^ ^ ^ decision step is completed by calculating the average value of the second set of the group. 10. If the request item 7 is ρρ φΙ . , , /, the step contains a step for limiting the angle measurement to a predetermined range.如. If the request item 1〇 is the next time, the predetermined range is [-10. Between 10". J 12 · - a player / recorder for playing / remembering a disc, the player / (10) μ contains a system such as a request item. 14. A type containing the request item j Computer of the system of 2, 3, 4, 5 or 6. - Determining the computer program product for a plurality of points applied to a disc relative to the optical duo angle n (ΑΜ), the computer program product 〇 3 The instruction code for implementing the method steps of claim 7, 8, 9, 10 or 11. 118361.doc