TWI277963B - Optic disk recognizing method - Google Patents

Abstract

Disclosed is an optic disk recognizing method, which determines the type of a source optic disk in a movement period of an optic pickup. The method includes the steps of detecting to obtain a first focusing error signal, wherein the first focusing error signal has a trough value less than a first threshold; and detecting a second focusing error signal peak value of a second focusing error signal that is greater than a second threshold within a predetermined time period starting from the time when the first focusing error signal is acquired, and in case there is no such a second focusing error signal peak value satisfying the condition, then detecting to obtain an RF level signal peak value of an RF level signal that is greater than a third threshold at a time after the predetermined time period to the movement period of the optic pickup. As such, an optic disk drive can correctly determine if the type of the source optic disk belongs to a single-layer disk, a DVD dual-layer disk or an SACD dual-layer disk and then correctly read the contents of the optic disk.

Description

1277963 --------- V. DESCRIPTION OF THE INVENTION (1) Technical Field of the Invention The present invention relates to disc discrimination and double method, and is particularly relevant for discriminating according to the disc The party successively appears with the signal size to judge: ί: f and an RF level signal layer disc discrimination method. J disc type disc discriminating and double [previous technology]

Ik has developed the level of information technology, in order to make it more savvy, and the various storage media have been awarded a lot. The noise is small and the life is:: store = body,;! High recording density (replacement, low cost, and a wide range of applications during the reading process, which can be influenced by the effects of dust and dust, etc., which makes it not only music, but also music. The consumer goods of the people's livelihood has become the heart of today's electric power. The existing storage media products can be divided into three types according to their different records: Becky meritorious 匕1·Read Only CD, such as Ray Recording ((3)

Audio), CD-ROM, CD ©Video, digital video disc (DVD-Vide) and digital light (DVD-ROM). ', 2, Write Once and Read Only, or Recordable, such as a recordable disc (Γη - R). ' ν ... 1277963 V. Invention description (2) 3 · Repeatable reading and writing ( · (Erasable) W ; eWFltable) or wipeable type _, phase change disc "chip = (M0), mini disc (RW) And digital tongue "PD", re-readable optical disc (CD-in which, ton-稷 is a type of optical disc (DVD-RAM), etc.. Writeable type of light monument 5SH type mat light ^ disc main 甩For the production of audio discs and video discs, the function is mainly applicable to this one-time writing action, and there is no wipeable material, such as a document file that can be erased for a long time and cannot be erased. ^ ΐ Ϊ Ϊ The establishment of medical records, etc., and the importance of the new number = two times of recording, reading and wiping in recent years. d,! Advantages, for example, because the memory capacity of dvd is at least peak = more than the disc 2° times, so the capacity is larger, and (image resolution is very good, Γ σ quality is very good, its horizontal resolution is as high as 500, 1 \ ^ / 匕 force far exceeds VCD), 32 kinds of subtitles, number of channels

Dvm tail W can accommodate multi-language, multi-national subtitles, etc., and all of them show toughness; 丄, and some CDs are produced. It is expected that DVD discs will gradually become mainstream products in the optical disc market within a few years. It is called SACD (Super Audio Compact Disc).

^ Also known as the "Super CD" storage media, after the invention of the CD, the new products and music discs that exceed the CDI voice quality. ^(3)=The sample frequency is 282 2·4ΜΗζ, which is the 64 hearts of the general CD 44·1ΚΗζ sample and the SACD frequency range is more than 1〇〇ΚΗζ, which makes the ^D improve the original c D music. A chilly stereotype, with a more subtle, more detailed, softer sound. Looking further, SACD

Page 6 1279963 5, invention description (3) The recording method is to use DS DI voice technology (Direct Stream Digital) to record, eliminate the traditional PCM recording method, all signals are • 2. 8224 ΜΗζ (seed CD 44.1 kHz sampling 64 times) high sampling mode, that is, 2800 samples per second, with 〇 and 1 continuous quantization, the dynamic range of the audible frequency domain is about 120dB, and may be recorded in the frequency domain about l〇〇〇 kHz, directly, the analog music signal waveform is pulsed into a digital signal, which is called the "direct bit stream digit", because the music is left in the space of nearly four times the CD, so it can provide better sound. The effect, plus the high number of samples, so the sampled waveform is very round, closer to the original analog-like waveform, so the sampled waveform is very close to the original analog waveform. In addition, since SA(3) does not use multi-bit, it can eliminate the bit conversion program, reduce the distortion and noise that may occur due to digital filtering, and is not as easy as multi-bit system (the higher the bit is, the more It's easy to be affected by power or external dryness, so the theoretical quality will be stable, and SACD can also accommodate multi-channel and video. SACD multi-channel sound quality includes 6 independent 曰 masters and one track. : You can read the full DSD bit rate without any compression. Compared to the normal DVD, you can only hear the sound quality of 96K/24Bi t. Because SACD's own positioning and lbi t quantify the DSD direct data flow in terms of technical aspects and advantages, the SACD has a better sound quality. Another: = surface 'CD drive data access technology is also improved with a variety of storage media' its main structure includes the responsibility of reading and recording from the optical disc °, optical write head, moving the optical read head to a specific location The I-zone moving mechanism maintains the rotating mechanism of the stable rotation of the optical disc, and controls the optical reading and writing

Page 7 1277963 V. Description of the invention (4) • Head control circuit and signal processing circuit, etc. Among them, the key components of the optical reading system are composed of laser light, straight lens, condensing objective lens, cylindrical lens, light sensor (or light::), etc. = optical system, by optical Objective lens group, elastic support body This mechanical energy transducer consists of a focus-circulating system (or classified as mechanical, system) and an electromagnetic drive system consisting of focus servo, seek servo, tracking servo and master control ( Or classified as a servo control system). It is mentioned here that due to factors such as rotation and external vibration, the mechanical precision of the machine will be affected, causing the trajectory of the laser light to be up and down, left and right, or rotating and shaking. Therefore, the optical disk machine needs focus and tracking action respectively to accurately measure the laser spot. Appropriate to the pit and land. At present, several widely used methods of focusing and correcting, including astigmatic, critical angle (spot size), knife edge and foucau it, etc. De-driven focus actuation is achieved by comparing the received differences in the shape of the focus, near focus and far focus to the photosensor to obtain a focusing error signal (FES) The focus actuator corrects the focus and provides the servo control system to adjust the spot. The near focus and far focus caused by the objective lens moving up and down near the point will cause the focus error to change positively and negatively. Therefore, the focus error The signal is usually a curve; the more common methods of tracking and correction include single beam, three beam and wobble, which are used to compare the four-photon photoreceptors. With six write head source, receiving and electric drive shaft horse optical disc offset to drive astigmatism spot focusing signal 7 tiger voltage, focus differential pull method method 1279963 five, invention description (5) photon light The difference in light intensity received by the detector to obtain a tracking error signal (TES), thereby serving as a basis for tracking correction, wherein the tracking error signal is similar to the focus error signal The shape curve is generated by feedback to drive the actuator. As described above, taking the astigmatism method as an example, the waveform error exhibited by the focus error signal and the RF signal (radio frequency signal) in the photo sensor is as shown in the first figure, wherein the upper part of the first figure is astigmatism. The focus error signal value change diagram of the method 'the horizontal axis of the right angle represents the distance between the objective lens and the reflective layer of the optical disc. The vertical axis represents the amplitude of the focus error signal value, and the focus error singular value waveform can be classified as the near focus area. 11 〇, the positive focal region 1 2 〇 and the far focus region 1 3 0, the waveform segments in these regions represent the change of the focus error signal value in the near focus, positive focus to far focus, and the positive focus 1 4〇 At this time, the focus error ' is displayed and the width of the positive focus area 120 is the range of the appropriate optical disc data acquisition timing. On the other hand, the lower half of the first figure is a schematic diagram of the change of the signal value of the astigmatism method, wherein the horizontal axis of the rectangular coordinate represents the distance between the objective lens and the reflective layer of the optical disk, and the vertical axis represents the amplitude of the RF signal value. In this case, the peak-to-peak value (ie, the value of C) of the RF level signal (RF 1 eve 1 si gna 1) is defined as the reflection intensity of the RF signal, and the positive focus of the focus error signal is 1 4 〇 corresponds to The RF signal peaks at a position of 150, meaning that the RF signal reaches the maximum value at the correct focus' and the RF signal amplitude is greater than a critical value of 16 〇. Furthermore, each of the above focusing methods generates a focus error signal, and the signal waveforms are similar S-shaped curves. When the objective lens reaches the correct focus position, the focus error signal value is zero, and the distance is at the correct t focal position. In the positive direction and the negative direction, each will produce a positive and negative focus error of 1278963. 5. Inventive Note (6) The maximum value of the signal, H ' κρ is applied to the curve between the two extreme values by linear control. In this linear region error The waveform of the signal and the RFtfL ^ number is ~ down to the week. When the optical read/write head boundary value, it means that the polygraph will be on the correct focus day ^, and the RF signal will be listed as 'FZC (focus zero point 140. The focus error signal peak and valley respectively, and the dielectric is nearly linear) Therefore, in the second method to achieve the focus of the servo system work requirements. Each control loop design, usually use the characteristics of the poly two to determine whether the focus is correct, the secondary parabolic curve of the opening, that is, the sine wave is positive ^ Moves from the bottom up so that the RF signal is above a linear range where a certain focus has entered the s-curve, and the 'rf signal' reaches the maximum value, so it can be crossed by the focus error signal whether it is close to the focus zero-interlacing point representing the correct focus. P〇int), which is the aforementioned coke. In view of the fact that the development of optical discs and optical discs is in line with the integration trend of various types of products, it has grown and evolved with the growth of many optical and health products. It is used to read disc video and audio data and the mouth of the 丨 丨 丨 有 有 有 有 有 有 有 有 有 有 有 在 在 在 在 在 在 在 在 在 储存 储存 储存 储存 储存 储存 储存 储存 储存The design of circuits and wafers is also increasingly sophisticated. The trick is that J will develop a mechanism to meet the above-mentioned correct and fast interpretation of the storage media type = demand, and provide a smooth storage media data reading process for the CD player, and one of the research and development topics that Dad needs to handle. It is hoped that the present inventors are hereby, and the inventors have been based on many years of experience in research, application and related product development and maintenance of optical storage medium read/write device control circuits and chip design related technologies. The idea of improvement, the lack of personal expertise, through multi-disciplinary research design and topical discussion,

Page 10 1277963 V. Description of invention (7)

The law can solve the above problems that have finally been studied. Disc discriminating and data reading side [square piece its misfocus, gathering signal capacity learning in the ft method disc invention content] The method of the invention 'is used in the category 'the first step in the first step ¥ first Focus error signal valley difference signal - error signal and focus error signal cycle end number and its peak value, the optical disk drive can take the head to move the SACD CD CD layer to the correct course. According to the present invention, the film is also used to directly detect the peak value of the first error time, which is less than the first predetermined time. Therefore, it is sufficient to use the optical recording disc in the current cycle instead of reading the data once. The optical disc is a single-layer film, and provides a double-layer optical disc discriminating reading head movement period to discriminate a double-layer optical disc detection. Measured to obtain a first focus error ^:, the number includes a first focus error signal peak value, a value and a first threshold, and the first focus threshold, and then the first focus detection is greater than a second convergence of the second threshold and if the first condition of the condition is not determined after the predetermined time period until the optical read head shift is greater than a third threshold, the Μ level is for reading The invention discloses a double-layer disc discriminating method for the invention of the SACD disc, and determines and discriminates the double-layer disc type as a DVD double-layer film, and then focuses the laser light source for smooth storage of the media data. The invention provides a disc discriminating method for discriminating a disc type in a moving period of a disc, which may be a SACD disc and a DVD double-layer light, etc., and when the disc player is not inserted into the disc

Page 11 I277963 Disc Judgment Operation - The first focus threshold is based on taking the second one. After the third time, the third side is confirmed by the JL and the relevant purpose and method. The RF level is judged by the speed. Interpretation or single-layer correct reading of the review committee's understanding of the program, such as the method can also be programmed, the disc focus, η difference signal error signal peak 'and the above-mentioned threshold conditions to the optical limit of the invention of the fast-track program into the advantages , is in ~. Signal Peak CD player disc source CD, which takes the disc player to the book and after the recognition 0. First, the first first of the first reading head, an RF quasi-optical disc, and the optical Read the value of the read head is one of the kind of film, the film content of the invention, I would like to be judged by the film, which 'a first focus error tomb error: focus error two focus moving position signal to determine the source light to read When the double-layered head is moved and the correct reading is performed, the human genus is used for the optical sputum technology, and the invention is described (8). The correlation and the correct I first detect to obtain the J signal including a value and a -th to the threshold value, and the detection within the connection is greater than Ϊ: and if the untested person is at the predetermined T to obtain greater than - The CD player can take the head movement period and then focus and follow the above method and the disc discriminates the focus error signal and the source disc type data. Therefore, it can be quickly taken, and can be correct, SACD disc To take the head to the relevant position, in order to make the function more advanced - step-by-step detailed description, 'then, to indicate that the method steps are the first focus error, the focus error signal signal valley value is less than the signal from the predetermined difference signal and Its peak error signal detects its peak before the end of the period. Because of the law, the type of optical reading, the data. In the disc discriminating direction, the disc is determined by the timing to take the disc inside the disc player for the DVD double decking and optical reading and the achieved embodiment and matching

Page 12 1279963 V. INSTRUCTION DESCRIPTION (9) [Embodiment] The present invention relates to an optical disc discriminating method for discriminating optical disc types based on the occurrence time and size of a focus error signal and an RF level signal. . Please refer to the second figure, which is a double-layer disc discriminating method of the present invention. A preferred embodiment. In this embodiment, the flow of the method for discriminating the two-layer disc includes the following steps: First, the position of an optical pickup is moved from low to high in step S20, and the total time taken for the whole process is an optical The first head focus error signal FE 1 includes at least a first focus error signal peak FE l_Peak, and a first focus error signal FE 1 is detected in step S 2 2 0. A focus error signal valley FE l_Bottom and a first threshold FE l_Thr 1, and the first boundary error signal valley FE 1 - Bottom is smaller than the first threshold FE 1 _Thr_1. Then, in step S24 0, the detection of the first focus error signal 'FE 1 for a predetermined time T 0 (for example, half of the optical pickup movement period) is greater than one; the threshold FE 2_thr_2 Whether the second focus error signal peak FE 2_Peak appears in one of the two focus error signals FE 2, and if so, it can be determined that the double-layer optical disc belongs to a DVD double-layer optical disc; if there is no greater than this second period during this period For the threshold value FE 2_thr_2, the second focus error signal peak FE 2_Peak appears, and then step S 2 60 is performed, and after the predetermined time TO reaches the end of the optical pickup moving period, it is detected whether there is more than a third. The RF level signal RF RFLL 2_Peak of the RF level signal of the RFLVL 2_thr_3 is present. If it occurs, it can be determined that the double-layer disc belongs to a SACD disc. Here, step by step

Page 13 (s) 1277963 V. Invention Description (10) Step S 2 6 0 may include first detecting to take 彳曰i, wherein the first level of the first level of the signal hunger VL LPeak is greater than the -L 1 The first RF level signal peak • Peak RFLVL 2_Peak appears ° ^ & beam detection" level signal. Here, it is gathered to identify the ^ (3) disc. ^ m ^ a M r 2 is used to monitor the distance between the optical disc and the objective lens to maintain the correct reading focal length, and to further illustrate the shape of the focus error signal and the RF level signal of the preferred embodiment = two == using the focusing method and The focus error signal and the above-mentioned different mode are used to assist the % Ming. The third system is based on the astigmatic method focusing and photo sensor of a preferred embodiment of the prior art. Since the astigmatic method uses an objective lens 310 a cylindrical lens 32 〇 and a quarter-light sensor 33 〇, the quarter-light sensing when the distance between the reflective layer of the optical disk 300 and the objective lens 3 of the optical pickup is changed to cause a different focus position The spot on the 3 3 3 呈现 presents a different shape. Therefore, the 'focus error signal value can be used, for example. Formula FE s = (A + C) - ( B + D) to obtain:, and the rF signal can be, for example, the formula rF = (A + B + C + D) or RF = ( a + C) + ( B + D) is obtained, and the peak-to-peak value of the RF level signal RFLVL is “the reflection intensity of the signal, where the light two f body A 331 , B 3 3 2, C 3 3 3 and D 334 will receive different drinking reflections respectively. The light intensity produces different signal values, for example, when it is located in the near-focus region 1 1 0 shown in the first figure, because the photodiodes A 3 3 1 and C 3 3 3 are weakly received, and the photodiode B 3 3 2 It is stronger with D 3 3 4 , as shown by the quarter-light sensor 3 3 0 a, so a negative focus error signal will be generated. For example, in the positive focal region 120, because the four photodiodes 33丨 to 334 are received by the light intensity phase

Page 14 1279963 V. Description of the invention (11) Similarly, the focus error signal obtained during correct focus is zero, such as the result of the quad-split sensor 3 3 0b, and the RF signal and the RF level signal are maximized. The value means that the RF level signal peak RFLVL_ Peak is generated. In addition, when located in the far focus region 1 130, the photodiodes A 3 3 1 and C 3 3 3 receive strong light, and the photodiodes B 3 3 2 and D 3 3 4 receive weak light, such as a quarter light sensation. The result of the detector 3 3 0 c, thus producing a positive focus error signal. Then, the focus servo system can use this focus error signal and RF signal as input, and then provide appropriate compensation with the compensation circuit to adjust the focus action and result. The third B diagram is a schematic diagram of a knife edge method and a photo sensor according to a preferred embodiment of the prior art. Since the knife edge method uses an objective lens 310, a cylindrical lens 3 2 0, a blade 3404, and a dichotomous sensor 350, etc., the focus error signal value can be calculated by the formula FES = D D2 is obtained, and if the light intensity of the light diodes D 1 3 5 1 and D 2 3 5 2 of the photosensor 350 is the same when focusing, the focus error signal is zero; D 2 3 5 2 When the near focus is received, the light intensity is greater than D1 3 5 1, so a negative focus error signal is generated, and D1 351 receives a light intensity greater than D2 352 at the far focus, thus generating a positive focus error signal. In addition, the Fuke method is based on the disadvantage that the knife edge method is difficult to control at near focus, so the rim is replaced by 稜鏡, and the light intensity is sensed by four photodiodes D, D 2, D 3 and D 4 . The principle is similar to the edge _, so it will not be described here. On the other hand, the critical angle method of the light sensor structure is also similar to the knife edge method, which uses a reflection 稜鏡 to detect the focus error signal by adjusting the angle of the light entering the reflection ,, wherein If the light enters the 平行 parallel, it will produce total reflection, so that the two photodiodes in the photosensor receive the same light intensity, so the focus error

1277963 V. INSTRUCTIONS (12) The signal is zero; in the far focus and near focus, the convergence or divergent light formed by the focus error will cause the light to partially refract, so the light intensity received in the two photodiodes The difference produced can be used as a focus error signal. The third C-picture is a schematic diagram of a spot-focusing and photosensor according to a preferred embodiment of the prior art. Since the spot method uses a three-spot light sensor • 360, and the light sensor 360 has three photodiodes A 3 6 1 , Β 3 6 2 and C 3 6 3, the focus thereof The error signal value can be obtained using the formula FES= ( A + C) -B. When in the positive focus, the sum of the light intensities of the photodiodes A 3 6 1 and C 3 6 3 is equal to the value of the photodiode B 3 6 2, thus making the focus error signal zero; #在近焦, will produce positive The value of the focus error signal, while located at the far focus, will produce a negative focus error signal. Please refer to the fourth figure, which is a preferred embodiment of the optical disc discriminating method of the present invention. In this embodiment, the flow of the disc discriminating method comprises the following steps: First, the position of an optical pickup is moved from low to high in step S400, and the total time taken for the whole process is an optical The first head focus error signal FE 1 includes at least a first focus error signal peak FE l_Peak, a first focus, and a first focus error signal FE 1 is detected in step S4 2 0. The error signal valley value FE 1 — Bottom and a first threshold value FEl_Thrl, and the first focus error valley value FE l_Bottom is smaller than the first threshold value FE l_ThrJ. If it is determined in step S42 0 that the first focus error signal bottom value FE l_Bottom is smaller than the first focus error signal FE 1 of the first threshold FE l_Thr_1, the optical disc player may determine that the first focus error signal FE 1 is not placed in step S49 0. Disc and issue an error and follow-up message to indicate the user's relevant and correct operation

1277963 V. INSTRUCTIONS (13) Procedure. On the other hand, if the first focus error signal FE1 is measured in step S4200, step S440 is performed to obtain the first focus error number FE1 for a predetermined time T0 (for example, an optical pickup). One half of the time of the shift period is greater than a second threshold FE 2 -thr 2 and one of the second focus error signals FE 2 is the second focus error signal peak FE 2 —Peak is ''. Appears if When present, it can be determined that the double-layer optical disc belongs to a DVD double-layer optical disc, and if there is no second focus error signal peak FE 2 — Peak appearing during the period, which is greater than the second threshold value FE 2 thr c , Then, step S 4 6 0 ' is performed after the predetermined time T 0 to the end of the optical pickup moving period, and it is detected whether there is an rf standard greater than a third threshold RFLVL 2 -thr-3 The RF level of the RFLVL 2 signal peak RFLVL 2-Peak appears. If it appears, it can be determined that the double-layer disc belongs to a SACD disc. In this case, the step S4 6 0 may further include detecting the first RF level signal RFRFL1 and detecting whether the RF level signal RFRFL 2 -Pak of the RF level signal RFLVL 2 is present. After the SACD disc is discriminated, if the RF level signal RFRFL 2 —Peak that is greater than the third threshold rfl VL 2 _ thr 3 is not measured in step S 4 60 , the step S48 0 may be performed. It is determined by the optical disc drive that the disc type belongs to a single layer. In order to further illustrate the present invention and related preferred embodiments, reference is made to the fifth figure, which is a schematic diagram of the focus error signal, the RF level signal, and the threshold waveform during the optical pickup movement period of the present invention. The oblique line extending from the lower left to the upper right represents the trajectory 5 1 0 formed by the moving position of the optical pickup from the low point 5 11 to the high point 5 1 2 during the movement period of the optical pickup head, during this period, according to the fourth A preferred embodiment of the optical disc discrimination method of the figure

Page 17 1279963 V. Description of the Invention (14) ^ When the optical pickup position is moved from the low point 5 1 1 to the high point 5 1 2 in step S 4 0 0, the detection is performed in step S42 0 to obtain a first focus error. The signal fe 1 5 2 0, wherein the first focus error signal FE 1 5 2 0 includes at least a first stacking error signal peak FE 1 - Peak 521, a first focus error signal valley value fe ! - Bottom 5 2 2 And a first threshold FE 1 -Thrl 5 2 3, and the first focus error signal valley value FE 1 - Bottom 5 2 2 is smaller than the first threshold fe 1 - Thr_l 5 2 3 . If it is not determined in step S42 0 that the first focus error signal valley value FE l_Bottom 5 2 2 is smaller than the first focus error signal FE 1 5 2 0 of the first threshold FE 1 - Thr - 523, Next, in step S49 0, it is determined that the optical disc is not placed, and an error and a subsequent prompt message are issued to indicate the relevant and correct operating procedure of the user. On the other hand, if the first focus error signal f E 1 5 2 0 is measured in step S 4 2 0, step S 4 4 0 is performed, and the first focus error signal f E 1 5 2 0 is obtained. One predetermined time T 0 5 3 0 (for example, half of the optical pickup moving period) is greater than a second threshold FE 2 - thr - 2 543, one of the second focus error signals FE 2 540 Whether the second focus error signal peak fe 2 -Peak 541 is present, so that the double-layer optical disc belongs to a DVD double-layer optical disc; if there is no second greater than the second threshold FE 2_thr_2 543 during this period The focus error signal peak FE 2 —Peak 541 appears, and then proceeds to step S46 0. After the predetermined time TO 530 and before the end of the optical pickup moving period, it is detected whether there is more than a third threshold MLVL 2 . A thr-3 5 62 RF level signal RFLVL 2 56 0 RF level signal peak RFLVL 2 a Peak 561 appears 'if any, it can be determined that this double-layer disc belongs to a SACD disc. Here, step S46 can still include at least

Page 18 1279963 5, invention description (15) First detection to obtain a first RF level signal RFLVL 1 5 5 0, and then speculate the RF level signal RFLVL 2 5 6 0 RF level signal peak rflvl 2 Whether the Peak 5 61 appears, according to the SACD disc. The first RF level signal RFLVL 1 5 5 0 has a first RF level signal peak RFLVL 1—Peak 551 and an RF threshold RFLVL 1—Thrl 552, and the first 1^ level signal peak 1 ^1^[1? The magnitude of 551 is greater than this {^ threshold RFLVL 1 - Thr 1 5 52. Finally, if the RF level signal RFRFL· \ a Peak 56 1 ' of the second threshold RFLVL 2 - thr - 3 562 is not measured in step S46, the disc may be determined by the disc player in step S48 0. Type _ in a single layer. Therefore, the present invention is a novelty, progress, and the patent application requirements stipulated by the 利用利法 of the industrial use country, and it is undoubtedly determined to apply for a patent for the invention. For sweeping

- However, the above is only one of the inventions, and the mother is not used to define the shape, structure, and life of the present invention. The equivalent changes and modifications of the present invention are included in the scope of the patent application of the present invention.

1277963 Brief description of the drawing [Simplified description of the drawing] First figure: it is a focus error signal and RF signal-value change diagram according to the conventional astigmatism method; Second figure: it is a preferred embodiment according to the present invention FIG. 3 is a schematic diagram of an astigmatic focusing and photosensor according to a preferred embodiment of the prior art; FIG. 3B is a diagram A schematic diagram of a knife edge method focusing and photosensor according to a preferred embodiment of the prior art; _3C diagram: a schematic diagram of a spot focusing and photosensor according to a preferred embodiment of the prior art; FIG. 4 is a flow chart showing the steps of the disc discriminating method according to a preferred embodiment of the present invention; and FIG. 5 is a shifting period of the optical pickup according to a preferred embodiment of the present invention. Schematic diagram of internal focus error signal, RF level signal and threshold waveform [Main component symbol description] 1 1 0 near focus area #2 0 positive focus area 1 3 0 far focus area 1 4 0 positive focus 150 RF signal peak 1 6 0 threshold

Page 20 1279963 Brief description of the diagram 300 optical disc 3 1 0 objective lens 3 2 0 cylindrical lens 330, 330a, 330b, 330c quarter light sensor 33 332, 333, 334, 35 352, 36 362 , 363 light diode 3 4 0 blade 3 5 0 dichotomous sensor 3 6 0 three-spot light sensor 101 0 optical read head movement track 5 1 1 optical read head position low point 5 1 2 optical reading Head position high point 5 2 0 first focus error signal 521 first focus error signal peak 5 2 2 first focus error signal valley 5 2 3 first threshold 5 3 0 predetermined time 5 4 0 second focus error Signal 5 4 1 second focus error signal peak - 4 3 second threshold i 5 50 first RF level signal 551 first RF level signal peak 5 5 2 RF threshold 5 6 0 RF level signal

Page 21 1277963 Simple illustration of the diagram 5 6 1 RF level signal peak 5 6 2 Third threshold Page 22

Claims (1)

1277963 VI. Patent Application No. 1 · A double-layer disc discriminating method for discriminating a double-layer disc type in an optical pickup moving period, the method comprising the following steps: a focus error signal, wherein the first focus error signal comprises a first focus error signal peak, a first focus error-difference signal valley and a first threshold, and the first focus error signal valley Less than the first threshold value; detecting one of the second focus error signals, one of the second focus error signals, and the second focus error φ difference signal peak value, within a predetermined time from the obtaining of the first focus error signal; The second focus error signal is not detected, and is detected between the predetermined time and the optical pickup moving period to obtain an RF level signal peak that is greater than one of the third threshold RF level signals. 2. The double-layer disc discriminating method according to claim 1, wherein detecting the peak of the focus error signal greater than the second threshold value is used to discriminate the double-layer disc system and a DVD pair Layered disc. 3. The method of discriminating a two-layer disc according to claim 1, wherein the RF level signal greater than the third threshold is detected between the predetermined time and the optical pickup moving period. The peak value is used to determine the double-layer* optical disc system as a SACD optical disc. 4. An optical disc discriminating method for discriminating an optical disc type during an optical pickup moving period, the method comprising the steps of: detecting to obtain a first focus error signal, wherein the first focus error signal Including a first focus error signal peak, a first focus error Page 23 8 1277963 6. Applying the patent range difference signal valley and a first threshold, and the first focus error signal valley is less than the first threshold; • starting from the first focus error signal Detecting one of the second focus error signal peaks of one of the second focus error signals greater than a second threshold within a predetermined time; and - if the second focus error signal is not detected, after the predetermined time to the optical read Detecting between the head movement periods to obtain an RF level signal value greater than one of the third threshold RF level signals. 5. The optical disc discriminating method of claim 4, wherein the detecting the peak value of the focus error signal greater than the second threshold value is used to discriminate the double-layer optical disc system from a DVD double-layer optical disc. . 6. The optical disc discriminating method of claim 4, wherein the peak of the RF level signal greater than the third threshold value is detected between the predetermined time and the optical pickup moving period. It is used to discriminate the double-layer optical disc-chip system-SACD optical disc. 7. The optical disc discriminating method of claim 4, wherein if the second RF level signal peak value greater than the third threshold value is not measured during the optical pickup head movement period, The disc type is a single layer. Page 24