TW200306548A - Optical pick-up apparatus, optical disc apparatus, optical apparatus and compound optical device - Google Patents

Abstract

The present invention is related to optical pick-up apparatus for regenerating the optical disc record and is provided with the followings: the first diffracting optical grating (45) for dividing light emitted from the integrated emitting/receiving device (31) into the zero order light and ± first order light; the second diffracting optical grating (46), which diffracts the optical path of the light reflected from the optical disc (2); and the third diffracting optical grating (47), which is disposed at the position where the + first order light diffracted through the second diffracting optical grating is incident so as to diffract the + first order light and compensate the optical path variation. The integrated emitting/receiving device is disposed at the position where the - first order light diffracted through the third diffracting optical grating (47) is incident. By receiving the - first order light, a focus error signal FE is obtained. In addition, by receiving the light, which is reflected from the optical disc, of the ± first order light divided by the first diffracting optical grating, the traced error signal is obtained.

Description

200306548 Rose, Description of invention: [Technical field to which the invention belongs]

The present invention is a right optical recording device for information recording and "optical disc" phase change optical discs and other optical pickup devices for optical use = two ^ information and reproduction of the recorded information one and an optical disc device equipped with the optical pickup device, further one ^ And Lu is related to the use of emergency optical devices and integrated optical elements to form integrated electronic devices on these devices. This application is based on the following year 2 The number 2001_358244 is its _ declaration. Those claiming priority on the basis of this patent application are cited in this application with reference to these application documents. [Prior Art] Do n’t have a kind of optical disk, phase change type Optical pickup devices such as optical discs for recording and reproducing information are carefully recorded, and such optical pickup devices for recording and reproducing information are provided with a diagram! The optical system shown is shown in the figure! The school system 2001 is damaged in the order of the optical path: the light source 211, which emits laser light projected on the optical disc 204, and the composite optical element 212, which has: divides the light emitted from the light source 211 into 3 1 Beam of the knife Diffraction grating 2 12a and diffraction grating 2 12b used for beam splitter before separating light emitted from the optical disc 2104; opening aperture 2 1 4, JL # is used to receive, /, is used to output The light is focused to a specific value. Kong Xing, the objective lens 215, which focuses the emitted light on the optical disc 204; and the light receiving unit 2,6, which receives the light returned from the optical disc 204. Money 211 uses semiconductor laser to emit laser light. Composite optical element 212 system-body three-beam diffraction grating and beam splitter diffraction grating 200306548 2:12: t: element. Three-beam diffraction grating fairy In order to obtain the following error signal by the so-called = method, the self-light source 2 " emits 212W self-light: 2 = three beams of human light. The beam splitter uses a diffraction grating to project it back to the disc 2G4. The light is diffracted and divided into 0-order light and the light is separated from the emitted light as the reflected light guided by the receiving light. Therefore, it is called. There is a three-beam diffraction grating 2i2a: # 之〇 Detectors for the primary beam of the secondary light; and the first and second detectors for the side beams of the first and second groups of diffraction gratings 212 that receive two beams in the returned light, respectively. It is not shown in the picture. The optical subsystem M1 uses the so-called astigmatism method to detect the focus error signal =. Because: as shown in Figure 2A, _, C, the main beam uses light:,, and then return to the light The light-receiving surface is formed into a roughly square shape, and a division pattern is formed which has been divided into four equal parts by a set of dividing lines that pass through the light-receiving surface and + +, and is a straight parent of each other. In addition, the side-beam photodetectors are respectively disposed at opposite positions sandwiching the main-beam photodetector 221 therebetween, but they are not shown in the figure. As shown in FIG. 1, the optical system 201 is located at the self-light source. During the journey from 211 to the optical disc 204, the optical point of the light source 2U is used as the object point, and the optical points of the total vehicle points are set on the recording surface of the optical disc platform and the optical parts are respectively arranged. The optical system 201 uses the point on the recording surface 205 of the disc ⑽ as the object point during the return journey from the optical disc 204 to the light receiving unit 216, and sets the image point of the conjugate point on the main beam for the light receiving unit 216. Each optical component is arranged on the light-receiving surface of the detector 221. Therefore, the light emitting point of the light source 2U of the optical system 2101 and the point of the light receiving surface of the photodetector 2 2 i of the main 200306548 beam detector 216 also form a conjugate relationship with each other. A method of obtaining a focus error signal from each light receiving area h, of the main beam photodetector 221 described above will be described below. First, when the objective lens 21 and the recording surface 205 of the optical disc 204 form an optimal position, and the recording surface 205 of the optical disc 204 is in focus, the so-called correct focus is formed, the light received by the main beam photodetector 221 The shape of the beam spot on the surface is circular as shown in Figure 2β. However, when the objective lens 21 5 is too close to the recording surface 205 of the optical disc 204, it deviates from the correct focus state, and the astigmatism generated by the reflected light separated by the beam splitter diffraction grating 212b passes through the composite optical element 212, As a result, the shape of the beam spot of the main beam photodetector 22 1 on the light-receiving surface is an ellipse whose topographical axis spans the light-receiving area as and the light-receiving area C5 as shown in FIG. 2. Furthermore, when the objective lens 21 is too far away from the recording surface 205 of the optical disc 204, it also deviates from the correct focus state. The astigmatism generated by the reflected light separated by the diffraction grating 212b of the beam splitter passes through the composite optical element 212. As a result, the shape of the beam spot of the main beam photodetector 221 on the light-receiving surface is as shown in FIG. 2C. The shape of the topographic axis is an ellipse that spans the light-receiving area and the light-receiving area ds. Open shape comparison, forming an ellipse inclined only 90 degrees in the long axis direction. The main beam photodetector 221 is in each light-receiving area ^ h, and the output of the light returned by the heart is Sa, Sb5, Sc, and at St, the focus error signal 计算 is calculated as shown in the following formula 1. FE = (Sa5 + Sc5Hsb5 + Sd5) 200306548 That is, as shown in Figure 2B, the main beam is used by the photodetector 22 i on the objective lens: in the so-called correct focus state at the in-focus position, by the above formula 1 The calculated focus error signal FE is zero. In addition, when the main-beam photodetector 221 is too close to the recording surface 205 of the optical disc 204, the focus error signal FE is positive, and the objective lens 2155E ^^ 204 ^ f £ ^ S205. it ^? ^ 〇 A tracking error signal TE is received by the side beam photodetector and divided by the three-beam diffraction grating 212a, i times, and each side beam is detected by light. It is obtained by the difference of each output. The optical pickup device having the optical system 201 configured as described above is based on the focus error signal FE obtained by the main beam light m 221 of Youguang 216 and the tracking error signal obtained by the side beam light detector. TE 'hunting is driven by displacing the objective lens 215, the objective lens 215 moves the recording surface 205 of the optical disc 205 to the focusing position, and the emitted light is focused on the recording surface 205 of the optical disc 204. Reproduction information of the disc 204. The semiconductor laser such as the light source 211 has a property that the wavelength of the laser light is related to the ambient temperature. When the ambient temperature is D, the semiconductor laser body: the laser light wavelength of the laser light is at the temperature T, the normal temperature is λ0, the temperature change from normal temperature is fixed, and the temperature coefficient is C, which can be as follows Equation 2 is approximated. • (2) λτ = λ0 + 〇 · ΔΤ In addition, when the laser light is diffracted by diffraction gratings such as the above-mentioned diffraction gratings 2 1 2b, the incident angle is θ, and the angle of diffraction & , The relationship between the incident angle ㊀ and the diffraction angle θ of 200306548 can be expressed by the following formula 3. η, · sin0'-n · sin0 = m · λ / d · · · · (3) In addition, λ is the wavelength of the laser light, d is the grating constant of the diffraction grating, the number of diffractions, and η is the incident side The refractive index of the medium, n, is the refractive index of the medium on the emission side. In the above-mentioned optical system 201, the returned light is diffracted by the diffraction grating 212b of the beam splitter of the composite optical element 212. Since the main beam system is n = 1 and ㊀4, when the number of diffractions is +1, the Equation 3 is rewritten as Equation 4 below. η '· sin0' = X / d · · · · (4) From the above formula 2 to formula 4, in the case where the ambient temperature of the optical system 20 is set, the diffraction angle of the temperature τ is θ, τ , Equation 2 can be substituted into common = 4 to obtain Equation 5 below. (5) η, · sin0'T = 〇O + c · △ 丁) / d using the diffraction angle θ, 〇 can be from Equation 5 Furthermore, the diffraction angle at room temperature is θ, 〇, The following formula 6 is obtained. η '-sin0'T = n- · sine'〇 + c. Δτ / ά · ·. (6) From Equation 6, the diffraction angle θ at temperature T, τ can be expressed as shown in Equation 7 below. e'Tse'O + sirr ^ Cc · ΔΤ) / ((1 · η,)) ··· (?) As can be seen from Equation 7, the temperature of the reflected light, the diffraction angle θ of time, is also related to the optical Changes in ambient temperature around system 201 are related. / 、 Related, -10- 200306548 Secondly, in the optical pickup device, since the manufacturing steps are performed at normal temperature, the position of the light receiving unit 2 1 6 is adjusted so that the diffraction angle of the returned light is θ, 0. However, after adjusting the position of the light-receiving section 2 1 6, when the ambient temperature changes, the diffraction angle of the reflected light changes as shown in Equation 7. As shown in FIG. 3, the main beam light irradiated on the light-receiving section 216 The center of the beam spot on the light receiving surface of the detector 221 is shifted from a specific position. When the optical system 201 provided in the optical pickup device obtains the focus error signal via the light receiving unit 216, the light detector for the autonomous beam is irradiated on the center of the beam spot on the light receiving surface of the main beam detector 221. The center of 221 is shifted at least in any direction, so that the turn-out in the correct state is not 0 ', so the focus error signal FE is biased. As described above, since the optical pickup device performs focus control such that the focus error signal ^^ is 0, there is a problem that the objective lens 215 cannot be driven and controlled to the correct focus position. As described above, the astigmatism generated by transmitting light through T70 to T5 and taking light and setting it to the block makes it impossible to irradiate the returned light appropriately: the position of the light-receiving part called the main shot The beam detector 221, "the shape of the beam spot on the plane is shifted from a suitable approximate circular shape.

There is also a problem that the optical pickup device cannot be used at this time. [Abstract of the invention] The purpose of the present invention is to provide a kind of optical picking dream that can be used to position and improve the focus error signal. , As well as light, pre-placement and coupling optics for these devices. 200306548 The other purpose of Ben Qiming is to provide an optical device and a composite optical element = an Ai shape that can suppress the astigmatism of the optical system from the astigmatism of the light returned from the optical disc, and improve the reliability of the focus error signal. Devices, as well as the fiber placement and re-use of these devices. The optical pickup device of the present invention is provided with a light source that emits light of a specific wavelength t: an objective lens 'which condenses the light emitted from the light source on the optical disc' and condenses the light emitted from the optical disc by the condensing composite optics Components, complex = diffractive S-piece, which transmits the light emitted from the light source, and diffracts the returned light; and optical path change correction mechanism, which is configured to emit: The position at which the reflected light is incident is corrected to reflect the reflected light from the diffractive element caused by the wavelength change of the light emitted from the light source and directed to a specific position ... the optical mechanism is based on the return: it is corrected by the optical path change correction mechanism After the optical path changes, the light ¥ pick-up device shoots the self-light source on the optical disc through the objective lens, and separates from the optical path of the emitted light by the diffraction in the composite optical element. Then, the light A, the light hunting light private change correction mechanism corrects the optical path change of the return light generated by the diffractive element due to the change in the wavelength of the r emitted from the light source; the light receiving area receives the guide two sets, and then the light receiving mechanism Incorrect signal. Other optical pick-up devices that have a proper focus when shooting back light at the inch position include: a light source, which emits light at a specific wavelength of -12-200306548, and when splitting & g beams, it is separated from the light reflection The light beam that returns to the light, the beam emitted by the source and the disc disc, and the light avoidance of the light that returns to the light: the objective lens, which is Jiang You &You; correct astigmatism and correct The light returned from the optical disc is output on the optical disc, and is divided by the beam splitter. The "braking mechanism" is configured with a number of blades, although the incident light is incident; and a light receiving mechanism, which is In a number of: the received returning light is divided into a plurality of divided returning lights divided by the structure; the light is divided into: or: the surface formed by the light dividing machine. , 冓 W is composed of several planes or curved lines of the original heart Μ㈣Μ's emitted light guide # disk ^, straws will be properly corrected on the optical path that is emitted from the light source and emitted light = = from the entire incident The beam shape of the returning light in the optical splitting mechanism is like a government. The optical disc device of the present invention is provided with: optical cold soap for / bucket, $ clothing removal, which is for recording and / or regenerating information on the light beam; and The disc rotates to drive the pro. Jujube, and the first pick-up device has: Light source nine • oblique private, music & /, you emit light of a specific wavelength II ΓΓ It focuses the light emitted from the light source on the disc, there are: = Γ 回 之 光Condensing; composite optical element, which has light 70, ..., which transmits the light emitted from the source, and self-correction mechanism, which is arranged in the warp and beam The position of the upper beam Φ incident on the diffracted incident light is corrected to change the optical path of the incident light produced by the diffractive element due to the wavelength change of 7 times before emitted from the light source, and direct the incident light to a specific position; and Light receiving mechanism, which is based on several 2 & domain receivers, corrects the return of the optical path change after the optical path change correction mechanism 13 200306548 The optical disk device is rotated by the optical disk rotation mechanism and driven by the optical pickup device. Recording and / or reproduction. = Out ... The light beam emitted from the light source by the objective lens: / on the optical disc 'sub-hunting by the diffractive element of the composite optical element makes the self-taking device correct the cause by the optical path change correction mechanism: The change of the wavelength of light causes the change of the return light produced by the diffractive element, which directs the return light to the light receiving mechanism: the process :: Sakimitsu-accepts a focus error signal directed to the return cut of the specific position. Other optical disc devices suitable for the present invention are provided with: optical pick-up, = and / or reproduction information; and an optical disc rotation driving mechanism, which is a rotary ΐ :: disk: an optical pickup device having: a light source, which emits specific :: The beam is separated from the light path of the light emitted from the light source and the light path of the returned light via the disc ′ and the beam of the returned light: an objective lens that focuses the light emitted from the light source and focuses it on the optical disc. The returned light is condensed; the light splitting mechanism is separated by the beam splitter from the incident position of the returned light, and the returned light is placed in the 'and X-ray mechanism, which is connected to several light-receiving areas.丨 + The vertical, horizontal, and vertical knife-brake mechanism will return 4 light to the light; the light depends on the structure of the money. The ten-sided or curved surface: The optical disc device of the present invention is composed of a light source. ==, correct the astigmatism of the reflected light with the beam splitter, and adjust the astigmatism of the returned light appropriately, adjust I: -14- 200306548 Beam shape. The optical device I used in the above-mentioned optical pickup device is a light beam emitted from a light source. Light is transmitted through, and self-preparing, diffractive elements, and optical path variation correction mechanism 'are arranged in the bran: the light diffracted by the dish is reflected back to the position where the light is incident. The diffracted motion of the element causes the optical path of the returning light generated by the diffractive element ^ the wavelength of the emitted light is changed to a specific position. The returning light is guided to the optical device, and the emitting element emitted from the light source causes the light returned from the optical disc. Diffraction and discontinuity. Diffraction by the diffraction by the optical path change correction mechanism to correct the reflected light produced by the diffractive element due to the king knife, and the movement of the wavelength of the light emitted by the diffraction element: The focus of the optical pickup device is incorrect; the light is returned to the appropriate position of the light receiving mechanism in the light guide area.-Several light receiving areas are used. The other optical device of the present invention has: the beam emitted by the beam splitter and the reflected light reflected by the optical disc :, The blade is separated from the light source ^ tb & Spear Renya and corrected the astigmatism of the returning king of light; and the light division mechanism, which is separated by the system and returns to the position where the light is incident, and shoots ... 〖Into several light-receiving mechanisms that guide the light area of the document; light The cutting mechanism is composed of several planes or curved surfaces. The optical device composed of several dry surfaces as described above is directed to the optical disc by the light emitted from the light source, and the self-disc is returned by the beam splitter. The light is separated from the emitted light ^ Privately 'properly correct the astigmatism of the returned light, and adjust the beam shape of the returned light incident on the light splitting sub-mechanism. In addition, the composite optical element of the present invention includes: Diffraction element, which causes -15-200306548 to radiate from the light source > &,, & The emitted light is transmitted, and the change in the optical path of the optical disc is compensated. The structure is arranged at the position w where the diffracted light is incident, and the compensation is produced by the diffraction element produced by the light emitted from the light source. &Amp; $ ^ r The light path of the returned light from the dry house changes, and the position is fixed. The composite optical light-guiding optical disc of the present invention constructed as above, the optical path of the emitted light emitted from the original disc by the diffraction element is separated :: "the light is diffracted and the emitted light is emitted first. The motion correction mechanism compensates for the change in the distance from the light source: the light reflected by the diffractive element caused by the long change causes the light to be guided to the appropriate position of the light receiving mechanism having the focus misalignment and the first area of the optical pickup device. The other object of the present invention and the implementation of the energy performance described by the present invention with reference to the drawings M 2, with reference to the drawings: the benefits " can be further taken from the following 5 brothers β π / L . [Embodiment] Hereinafter, an optical disc device to which the present invention is applied will be described with reference to the drawings. The optical disc device 1 of the present invention is formed for cd (optical disc) α DVT (/ sample digital disc), CD_R (recordable) that can record information, and CD (rewritable) that can rewrite information. Optical discs, and optical discs 2 such as magneto-optical discs, record poor information and reproduce recorded information. :: Disc set 1 is equipped with an optical pickup car that records and reproduces information from disc 2. ^ Drives the disc rotation drive mechanism of disc 2 *; makes optical pickup = clothing set: a transfer mechanism $ that moves in the direction of disc ^; And the control unit for controlling the photon take-out 3, the disc rotation driving mechanism 4, and the transmission mechanism-16-200306548 The disc rotation driving mechanism 4 has a disc table 7 on which the disc 2 is mounted; and the rotation = moves the disc table 7 The spindle motor 8. The transfer mechanism 5 has a pedestal seat for supporting the optical pickup, movably supports the main shaft and the auxiliary shaft of the support base, and a lead-through motor for moving the support base, but it is not shown in the figure. As shown in FIG. 4, the control unit 6 includes a drive control transmission mechanism 5, an access control circuit 9 that controls the position of the optical pickup device 3 in the radial direction of the optical disc 2, and a biaxial actuator that drives and controls the optical pickup device 3. The word server circuit 10; and control = equal access control circuit 9 and feeding circuit! 〇Drive controller i = having: demodulation processing signal of the optical pickup device 3 signal demodulation = error correction circuit 13 for demodulation processing signal error; and outputting errors, βT after the signal to external computers and other electronics The interface of the machine ". The optical disc device 1 made up of ΓΛ is driven by the spindle motor 8 of the optical disc rotation drive mechanism 4 and is equipped with optical discs. Storage ::: The control signal of the road 9 'drives the control transmission mechanism # to take the device 3 to the position corresponding to the optical motion pre-disc 2 for the recording of the track n, and to reproduce the recording of the light 1 贝 Bei Xun. : Your Majesty, the above-mentioned optical pickup device 3 will be described in detail. The optical pickup device 3 is shown in Fig. 5 and learns the system 30; and The drive mechanism that drives the wooden lens to the objective lens will be described later. Optical pickup installation + optical integrated element 3 H optical system 30 has the following optical path order: receiving and emitting laser light: optical element body formation, The light-receiving element-its system = source and 2 beams from the optical disc Light; composite optical element ... The emitted light emitted by the 嶋 -body-type element 31 separates the -17-200306548 from the optical disc 2 and the emitted light; opening and closing the diaphragm 33, which will pass through the self-receiving and light-emitting integrated element 31 The emitted light of the emitted composite optical element 32 is condensed into a specific numerical aperture NA; and an objective lens 34 is used to condense the emitted light condensed by the aperture stop 33 above the recording surface of the optical disc 2. The body element 31 includes a semiconductor laser that emits laser light having a wavelength of, for example, about 780 nm, and a light receiving element that is divided into light receiving regions whose details are described later. As shown in FIG. 5 to FIG. 7, a composite optical element 32 if formed into a block shape by emitting a molding resin material, and having: a first surface 41 adjacent to the light-receiving and integrated unit 一体 and orthogonal to the optical axis of the light emitted from the light-receiving and integrated unit 31; and A second surface 42 that is parallel to the first surface 41 is provided on the first surface 41. The first surface 41 is provided with a light beam divided by the self-receiving and light-emitting integrated element into three beams including 0th order light and ± 1st order light. First diffraction grating c. The optical system 30 applies a so-called three-point method (three-beam method) in order to obtain a tracking error signal D, and detects and detects the first-order light divided by the first diffraction grating 45 through the light-receiving and integrated unit 31 and detects The difference of each output of ± 1st order light is constituted by tracking servo. I wish to grasp the gridless 46, which is to make the younger ... ~ ζ 疋 each of the reflected light is divided by the first diffraction grating 45 of the 0th light and ± 1st light diffraction, and further divides these into 0 times light and ± 1 time light, if the +1 time light is ^ reflected back: and separated from the light path of the emitted light. In addition, the first surface 41 is provided with the third and second diffraction gratings 46, and the returned light is further divided into 0th-order light and 1st-order light. The diffraction grating 47 is located on the first light beam, so that the Diffraction of the returned light, such as directing the -1st light to the light-receiving -18-200306548 body type TC member 31. The third diffraction grating 47 is disposed adjacent to one side of the first diffraction grating 45 in the same plane. The complex 0 light car element 3 2 passes through the return light separated by the second diffraction grating 46 and passes through the return light incident on the third diffraction grating 47 to give only a specific amount of image element & optical element. 3 2 By adjusting the position of the optical axis direction of the light emitted from the self-receiving and light-emitting integrated element 3 1, the defocus on the optical disc 2 can be easily adjusted. ^ The composite optical element 32 is formed by injection molding a resin material as described above. Other forming methods can also form the first diffraction grating 45, the second diffraction grating 46, and the third diffraction grating 47 described above by etching, or they can be formed by machining. In addition, the material forming the composite optical element 32 is not limited to a resin material, and a light-transmitting optical material such as a glass material may be used. Furthermore, the material structure may be locally changed by a combination of such optical materials. The composite optical element 32 can also be designed to have a reflective surface inside. In this way, by using the reflective surface, the freedom of optical design can be improved by bending the optical path. The following is a description of the change in the optical path of the light emitted from the optical disc 2 in the composite optical element 32 due to the wavelength variation of the light emitted from the light source of the light-receiving integrated element 31. As shown in FIG. 7, the composite optical element 32 uses the reflected light from the optical disc 2 as B, and uses the second diffraction grating 46 to diffract the returned light L into + 丨 order light and separate it from the optical path of the emitted light. The third diffraction grating 47 is configured so that the optical path is diffracted by the first: diffracted light and the outgoing light L, which is a -order light, and is guided to the light-emitting integrated element 31. 200306548 At this time, as shown in FIG. 8, in the composite optical element 32, the wavelength of the reflected light is λ, the diffraction angle of the second diffraction grating 46 is θι, and the diffraction angle of the third diffraction grating 叼 is ㊀2 'The grating constant of the second diffraction grating 46 is d, and the first constant is from 6 丄, the grating constant of the Le second diffraction grating 47 is t, the number of diffractions of the second diffraction grating 46 is +1, and the third diffraction The diffraction number of the diffraction grating 47 is _ 丨, and the refractive index of the medium between the second diffraction grating 乜 and the third diffraction grating 47 is n, that is, when the refractive index of the resin material forming the composite optical element 32 is n. From the aforementioned formula 3, the following formula 8 and formula 9 are derived. "Η · sinGii / d! Sin02-n · sinefj / d] Secondly, from Equation 8 and Equation 9, Equation 10 and Equation 11. • · · · (8) • · · · (9) sine 丨 and! ^ 2 can be expressed as si η θ 1 = λ / (d 1 · η) 8ΐηθ2 = λ · (l / dl-l / d2) Next, from Equation 10 and Equation 12 and Equation 13 of Equation u. • · · · (10) · · · · (11) COS01 & COS02 can be expressed as follows · · · (12) · (13) C〇s01 = (l ^ 2 / (di. Η) 2) ι / 2 C 〇S02- (1 ^ 2 · (l / d ^ l / d2) 2) i / 2, secondly, the second surface 42 is ㈣, from the third surface 42 to perpendicular to the first surface 41 + ": axis The deviation from the 忒 x-axis is the y-axis, and the second diffraction grating 46 is used as the two-ray diffracted light from the disc 2 and the first diffraction grating 45 is used as the main beam of human light as the light. At 11 o'clock, the light path of the ray 11 can be expressed as the following -20- 200306548 formula 14 4. y-tan0] · X · · ·. (14) Secondly, the distance between the first surface 41 and the second surface 42 is a, and the light 丨丨 It is the same as the first surface 4 1 ', that is, the position incident on the third diffraction grating 47 can be expressed as the following formula 15 • (15)

Therefore, when the return light diffracted by the third diffraction grating 47 for the first light is the light 12 ', the optical path of the light 12 can be expressed by the following formula 16. • (16) The position of point B can be expressed by the following formula: j 7 y = tan02 x + aCtanG ^ tanGa) Secondly, the intersection of light 12 and the x-axis is b, which is expressed. x — a (1-tanGi / tan02) 5 y = 0 (17) You can know that the position 乂 on the X axis is related to the diffraction angle ㊀ 丨 of the second diffraction grating 46. Since the diffraction angle θι is a function of the wavelength λ from Equation 8, in the above example, if λ is changed, the diffraction angle ㊀ 丨 changes, and the coordinates of ⑽ also change. The light-emitting integrated element is caused by the wavelength change of the emitted light. The position of the beam spot of the light receiving area of 31 is changed. Therefore, in order to obtain the position of the beam spot of the light-receiving area of the light-emitting-type element 31 regardless of the wavelength variation, it is determined. Use the formula ι0 to formula Η, and use λ to represent the right side of the formula of 乂 in formula 17 The term can be expressed as Equation 18 below. -21. 200306548 d 2 < d 1, tan0 1 / tan02 = (sinei / cose1) / (sin02 / cose2) • · · · (18) =-((d12d22 / (d2-d1) 2 ^ 2) / (n2d12 ^ 2)) 1/2 In this case, when formula 18 is substituted into the conditions shown in formula 19 below for finishing, formula 20 can be expressed as follows. (19) • (20) From Equation 19 and Equation 2G, we can see why, the X coordinates of the 6 points of the third diffraction grating 47 are constant. That is, if the composite optical element 32 is designed such that the grating constant d1 of the second diffraction grating 46 and the grating constant d2 of the third diffraction grating 47 satisfy Equation 19, the integrated light-emitting type & The position of the beam spot in the light receiving area of the "piece" is constant. Such a coupled optical element 32 defines the grating constant 1 of the second diffraction grating 46, and the grating constant d2 of the first,: ^ grating 47, because it is self-susceptible. When the wavelength of the emitted light emitted by the light-emitting integrated element 3 1 varies, the light returned from the optical disc 2 is diffracted by the second diffraction grating 46 + 1 time and separated from the emitted light, even if the separated reflected light is By using the third diffraction grating 47 to diffract the returned light -1 times, the light returned from the optical disc 2 can always be appropriately guided to a specific position of the light-receiving area of the light-receiving integrated element 31. The aperture stop 33 is disposed on the optical axis of the light emitted by the second diffraction grating 46 of the composite optical element 32. -22- 200306548 The objective lens 34 is composed of at least " solid convex lens, and is self-receiving light-emitting type Element 3! Is emitted and emitted by the aperture 33 which is condensed. The configuration of the above method is shown in FIG. 9 and FIG. 9. The light-receiving integrated element 31 has: receiving the main shot of the diffracting light booth * 4 5 times, and the main shot of Guixi Zhiren. The beam is a square 4 main beam photodetector 5i, and each of the two side beams that receives the phantom light divided by the first diffraction grating 45 is a set of side band-shaped side beam light. The detector M, 4 is a light-emission-type element 31 that is arranged so as to correspond to the incident position of the reflected light that is corrected by the gastric triple diffraction grating 47 of the composite optical element ^. The light-receiving-body-type element 31 is provided with a centrally-shaped and roughly square-shaped main: a beam photodetector 51 ′ and a set of roughly band-shaped photodetectors for sandwiching the main beam photodetector between the two sides. Side fire detectors 52, 53. As shown in FIG. 9, the photodetector for the main beam of the light-receiving integrated element 31 has a light-receiving region two diffraction gratings 47 that are divided into four equal divisions by a set of dividing lines that are orthogonal to each other, thereby correcting the optical path variation. The lens driving mechanism of the optical pickup device 3 includes a lens holder holding the objective lens 34, and the lens holder can be oriented in a focusing direction parallel to the optical axis of the objective lens and perpendicular to the objective lens. The bracket support member that is displaced in the two-axis direction of the tracking direction of the optical axis of 34; and the electromagnetic driving part that changes the lens holder drive to the two-axis direction by electromagnetic force, but it is not shown in the figure. The focusing error signal detected by the main beam photodetector 51 and the side beam photodetector M of the light-emitting integrated element 3 丨 the tracking error signal detected by the side beam detector 2003-200306548, respectively, drives the objective lens 34 to change It is located in the focusing direction and tracking direction, so that the emitted light is focused on the recording path of the recording surface of the disc 2. In addition, the 'composite optical element 32 can also separate the first diffraction grating and the second diffraction light by The grid 46 and the third diffraction grating 47 are formed as a hologram element by etching a specific hologram pattern. In addition, when a hologram element is used, a surface relief type hologram should be used, and a hologram can also be used to improve the diffraction efficiency. The optical disc device constructed as above 丨 outputs the control signal from the servo = channel 10 to the two-axis actuation of the optical pickup device 3 according to the focus error signal and tracking error signal detected by the optical pickup device 3 by the light emitted from the optical disk 2. The objective lens 34 is driven to change the focus direction and the tracking direction, respectively, and the emitted light is focused on the required recording track of the optical disc 2 through the objective lens 34. Then, the optical disc device 1 performs demodulation processing and error correction processing on the signal read by the optical pickup device 3 through the signal demodulation circuit 12 and the error correction circuit 13, and then outputs a reproduction signal from the interface 14. Hereinafter, the optical disc device 1 will be described with reference to the drawings on the optical paths of the emitted light and the returned light in the optical pickup device 3. As shown in FIG. 5, when the optical disc device 1 reproduces information from the recording surface 23 of the optical disc 2, the light emitted from the self-receiving and light-emitting integrated element 31 is divided into the light of the 0th order by the first diffraction grating 45 of the composite optical element W. And 3 beams of ± 1 order light. The emitted light divided into three beams passes through the second diffraction grating 46 of the composite optical element 3 2 and is condensed on the recording surface of the optical disc 2 by the objective lens 34 and is emitted from the recording surface 2a of the optical disc 2 The light is divided by the -24-200306548 two-diffraction grating 46 of the composite optical element 32 to separate the 忐 M η ^ ^ ^ _ human light and the magic light, and the +1 light is used as the reflected light and the emitted light. The splitting μ μ ^ JL is incident on the third diffraction grating 47. The incident on the second diffraction grating 47 — m is divided into the first error and the third diffraction grating 47 is diffracted, and the progress is reported. J becomes 0th order light and ± 1st order light. The "m light-body element 31 The main / received light enters the receiving bi, ci, and di. The respective light receiving areas ai of the beam use -1 are wider in the composite optical element 32, and the optical path variation of the returned light by the second diffraction grating 46 is changed. The third diffracted light is incident on the light-receiving integrated element 31. The return light appropriately enters the areas ai, bl, c, and dl. Each of the light-receiving photodetectors 51 of the beam detector 51 is directed to the recording surface of the optical disc 2 The best position for the city is to combine the recording surface 2a of the optical disc 2 with the correct focusing state as shown, the incident light: the beam receiving points a1, bl, cl, dl_ of each light receiving area 51 of the photodetector 51 The shape is formed as a circle as shown in Fig. 10B. When the circular beam spot is shown, the respective light receiving areas a1, G1 and each light receiving area b1, d1 of the main beam photodetector 51 facing each other are as follows: The amount of light is equal. When the objective lens 34 is too close to the recording surface 2 & of the disc 2, it is away from the correct focus state because it is separated by the second diffraction grating 46 and combined with optical The astigmatism generated by the element 32 is incident on the main beam for optical inspection: the beam spot shape of the return light of each of the cross regions a'bl'C1,1, as shown in FIG. 10A. The elliptical shape of the light-receiving area ai and f-light area q. Furthermore, when the objective lens 34 is too far away from the recording surface 2 of the optical disc 2, that is, ^ is out of the correct focus state, and is returned by the separation by the second diffraction grating 46 The astigmatism generated by the light passing through the composite optical element 32 is incident on the main beam for light detection »25- 200306548 51 of each light receiving area ai, bl, d, and the beam spot shape of the returning light, as shown in Figure 10C The elliptical shape showing the terrain growing axis spanning the light receiving area bi and the light receiving area di is compared with the shape of the beam spot shown in FIG. 10A described above, and forms an ellipse that is inclined only 90 degrees in the long axis 3 directions. Therefore, FIG. 10A is formed. In the case of the elliptical beam spot shown in FIG. 10C, the main beam uses the photodetector 51 of the two groups of light receiving areas opposite to each other ... q and the light receiving areas of each of the light receiving areas 1 ^, dl accept the The amount of received light is increased, and the amount of received light is reduced in each light receiving area of the other group. Therefore, the main beam uses light In the detector 51, each light-receiving area ai, bl, c, d, and each output detected respectively is the light-receiving area%, which is called, the sn focus error signal FE can be calculated as the formula 2i shown below. FE = (Sai + Sci) -(Sb1 + Sd1) · · · · (21) That is, the main beam photodetector 51 is located on the recording surface 2a of the objective lens 34 on the disc 2 and is located at the position #t "°", " Yeah, the focus error letter or FE calculated by the formula 21 is 0. When the main body hits 10 with a beam, the forward detector 51 is used to focus on the objective lens 34 and the green surface 2a of the disc 2 too close. When the error rank signal FE is positive and the objective lens 34 is too far from the light 'plane, the focus error signal FE is negative. As described above, subject to the selection of ^ 51 # | 八 士 八 ^^^ The first integrated beam 31 of the main beam with a light detector 3 i series hunting light incident on you, respectively, and 3, 口 口 光Areas & 丨, bi, ci, ... of each beam snack 1¾ out to obtain the center & ^ iron signal FE and obtain the regeneration letter f. Each side of a group of shots τ pie 45 is divided into ± 1 times ^ photodetectors 52, 53 are shaped by a first diffraction grating and a second diffraction grating 46: a square beam is reflected by the disc 2 to form the reflected light 'and The light is separated from the emitted light by +1 times, and then passes through the third winding-26- 200306548 ^ first: 47 ,: the positive optical path changes and enters to detect each light receiving area. Signal ΊΈ. The other difference is obtained, and the tracking error is obtained. In addition, the optical pickup system 3 is shown in Fig. U, and the optical system 6 is information; The driving mechanism is not diminished on the erection chart. The following description of the system 60's optics will be used to obtain the power and strength, which is similar to the structure of the optical system 30 with the light: clothes set 3. Note the same symbol and omit the 61 light! = Set the optical system with 3 ° 6 ° according to the optical path sequence: light source "emits laser light onto disc 2; composite optical element 62 cut + emitted from this light source 61 Light, which separates the light returned from the optical disc 2 and exits: separates and further divides the returned light that is separated from the emitted light; the aperture diaphragm 33 condenses the emitted light through the composite optical element 62 emitted from the light source 61 A specific numerical aperture NA; an objective lens 34, which records the light condensed by the aperture 33 and focused on the record of the optical disc 2; and a light receiving unit 63, which receives the light emitted from the optical disc 2 Light. The optical system 60 includes: a first light-shifting plate 64, which is connected to the light source 61 and the composite optical element to block unnecessary light beams other than the effective light beam emitted; and a second light-shielding plate M, which is connected to the composite optical element. An unnecessary light beam other than the effective light beam of the returned light is shielded between 62 and the light receiving unit 63. The light source 61 has a semiconductor laser that emits laser light having a wavelength such as about 7 8 from the light emitting point 6a. : ¾ As shown in FIGS. 11 to 12, the composite optical element 62 is formed into a block shape by emitting a molding material-27- 200306548 grease material, and has: adjacent to the light source 6i, and self-knotting: 1; light emitting point First surface 8a of the emitted light perpendicular to the emitted light of 61a: Taxi — ^ The first surface 81 is parallel to the second surface 82; the second surface 82 is inclined only: the angle is opposite to the third surface 83; and -The surface 81 and the second surface 82 are perpendicular to each other: the fourth surface 84 which is inclined to the third surface 83 only by a specific angle. : The surface 81 is provided with a first-diffraction grating 75- "diffraction grating 75" which divides the emitted light emitted from the light emitting point 61a of the light source 61 into three beams including 0th-order light and 1st-order light. 60 In order to obtain the tracking error signal D E, the so-called three-point method (two-beam method) is used, and the Israeli-Ireland receiving unit 63 receives the output of each of the first-order light measured by the first diffraction grating 75 and the light by the human. The difference is constituted by a tracking servo. The first surface 82 is provided with a second diffraction grating%, which is used to diffract the 0th-order light and local light that are divided by the first-diffraction grating 75 from each of the reflected light from the optical disc 2. These are divided into. The secondary light and ± 1st light are separated from the optical path of the emitted light as the return light. The third surface 83 is provided with a third diffraction grating 77, which is located by the second diffraction.

Light peach 76 is separated and shot back to Duo Xiben # L 耵 口 光 上 ", so that the reflected light is reflected and diffracted, tr is divided into 0 times light and 1 time light, if the] times light is reflected back The light compensates for the change in the optical path produced by a diffraction grating 76. A third reflection grating 77 is provided with a specific reflection film on the second surface 83 in the manner of total reflection of the reflected light from a person. The function of the reflective diffraction grating as shown by Hui. The fourth surface is provided with a division chirp 78, which is located on the optical path of the reflected light that has been changed by the third diffraction grating 7 and corrected. It is divided into 4 -28- 200306548 parts. As shown in Fig. 13 and Fig. 14, Hai Dao J 稜鏡 7 8 forms a roughly regular quadrangular pyramid opening / shape, and is reflected and reflected by the third diffraction grating 77. Diffraction of the _ 丨 second light at the section η / 、, where w-丨 :: The underlight is near the focal point of the diffracted light, or near the focal point, and the center of the diffracted light is incident on the center of the regular four corners = the vertex angle The division 稜鏡 78 is located inside the composite optical element 62 and is disposed toward the top corner on the inner side. That is, the division 稜鏡 78 is positioned by the first diffraction grating 75. The 0th-order light of the divided three beams is diffracted by ^ = diffraction grating 76, reflected and diffracted by third diffraction grating 77, and incident = arranged at the vertex angle. In addition, the division 稜鏡 78 is a positive four The bottom face of the pyramid is reflected and diffracted by the third diffraction grating 77. The optical axis of the secondary light is arranged in the following manner. The composite optical 7G member 62 returns the light and rain through the separated by the second diffraction grating 76. 'Only the return light incident on the division 稜鏡 78 is given only the specific:. The composite optical element 62 can easily adjust the defocus on the optical disc 2 by adjusting the position of the two directions of the emitted light emitted from the light source 61. Composite optics The element 62 is formed by injection molding as described above. Other formation methods can also be formed by the last name processing: the diffraction grating 75, the second diffraction grating 76, and the third diffraction grating: 1 can also be borrowed Formed by mechanical processing ... Bu, forming composite optics = = The material is not limited to resin materials, but also can use optically transparent optical fibers such as glass materials. Furthermore, optical materials such as this can also be used; Material structure. ，， 和 ΰ 局 植 ： 时 '与 以 Compound optical element 3 2 In the same way, the grating constants of the # 2 grating 76 and the third diffraction grating 77 and the third surface Γ3 and -29- 200306548 form the angle of the second surface 82, etc., to design a composite optical element 62, which compensates for the return The change of the optical path length of the light can correctly return the beam to the vertex of the light guide M and cut it 78. The compound optical element 62 designed in this way changes the wavelength of the light emitted from the _61 to 'from the optical disc 2 When the returning light is diffracted by the second diffraction grating into +! Secondary light and separated from the emitted light, even if the separated returning light changes, the returning light is reflected and diffracted by the third diffraction grating 77. The light returned from the optical disc 2 is always directed to the apex angle of the division, and the returned light divided by the division 稜鏡 78 can be directed to the specific light receiving area of the light receiving unit ^. Location. The aperture stop 33 is disposed on the optical axis of the light emitted by the second diffracted light thumb 76 through the composite optical element. The objective lens 34 is constituted by at least one convex lens, and is arranged so that the light emitted from the light source 61 is condensed on the optical disc 2 by the light condensed by the aperture stop 33. As shown in FIG. 15, the light receiving unit 63 has a roughly square main beam that receives a main beam that has been subdivided by the first diffraction grating 75 times. The main square beam is converted into a photodetector and received by the first diffraction beam. One of the two side beams of the ± first order light divided by the grating 75 is a photodetector 92, 93 for a sideband beam having a roughly band shape. The light-receiving section 63 is disposed at a position corresponding to each of the reflected light which is judged by the division prism Kawasaki of the composite optical element 62. The light-receiving section 63 is arranged in the center and is roughly arranged; a light detector 91 for the light beam is provided, and a group of roughly band-shaped light detectors 91 are provided between the light detector 91 for the main beam and sandwiched therebetween. Photodetectors 92, 93 for side beams. -30- 200306548 The main-beam photodetector 91 of the light-receiving section 63 has light-receiving regions d, which are divided into four equal parts by a short dividing line orthogonal to each other. In each of the light-receiving regions, b2, C2, and d2 are respectively irradiated with the return light divided by the divided 稜鏡 78 into four parts. The first light-shielding plate 64 is provided between the light source 6 and the composite optical element 62 with a roughly circular opening corresponding to the effective light beam emitted. The opening restricts the unnecessary light beams other than the effective light beam, so as to avoid The diffused light enters the composite optical element 62. The second light-shielding plate 65 is provided between the composite optical element 62 and the light receiving portion 63 with a roughly circular opening corresponding to an effective beam of emitted light. The opening is restricted by the opening: an unnecessary beam other than the cross beam is held. It is possible to prevent the diffused light that has not passed through the division 稜鏡 78 in the composite photon element 62 from entering the light receiving portion. The shapes of the openings of the first light-shielding plate 64 and the second light-shielding plate 65 are not limited to a roughly circular shape, and other shapes such as a roughly oval shape and a roughly polygonal shape may be formed. y ′ The first light shielding plate 64 and the second light shielding plate 65 are shown in FIG. 14 and FIG. 15, which only show that there is no light corresponding to the 0th order divided by the first diffraction grating 75, that is, the opening of the counterpart and the main beam. The shape of the part, however, also needs to be set to correspond to the primary light: that is, the opening 胄 corresponding to the side beam, or the shape of the opening part is changed. The lens driving mechanism of the pickup device 3 has: A lens holder for the lens, 4; a bracket supporting member that supports the lens holder to be displaceable in an axis direction parallel to the focusing direction of the optical axis of the objective lens 34 and an axis direction orthogonal to the tracking direction of the optical axis of the objective lens 34; and The lens support -31-200306548 is driven by an electromagnetic force, but the electromagnetic drive is not located in one axis, but it is not shown in the figure. The lens driving mechanism is based on the focus error signal detected by the main beam photodetector 63 of the light receiving unit 63 and the tracking error signal detected by the side beam photodetectors 92, 93. The focusing direction and the tracking direction make the emitted light focus on the recording path of the recording surface of the optical disc 2. In addition, 'the above-mentioned division of the combined optical element 62 稜鏡 78 can also be formed like an octagon. In this case' the light receiving section The main beam detection light 63 of 63 can also be divided into 8 parts by a radial dividing line from the center of the light-receiving surface. In addition, the '78 division of the composite optical element 62 is provided on the fourth surface 84. The inner side, but the fourth surface 84 may be protrudingly provided on the outer side. Furthermore, the division 稜鏡 78 of the composite optical element 62 is not limited to a flat pyramid, and may be formed into a shape having a plurality of curved surfaces. In this case, the second or second composite optical element 62 may be provided so as to correspond to the divided area of the main beam photodetector 9 丨 of the light receiving section 63. The first diffraction grating and the second Diffraction grating 76 and third diffracted light 77 is formed as a holographic element by etching a 4-inch holographic pattern. In addition, when a holographic element is used, it should be a surface relief hologram or a sparkle hologram to improve & radiation efficiency. As shown in FIG. 16, the optical element 62 uses a grating 79 divided into four regions instead of the division 稜鏡 78, and the same effect can be obtained. At this time, the grating 79 is provided to obtain the same effect as the division 稜鏡 78. The force of the divided region, w, y3, y4, each of the divided regions yi, but, but, h are different in the direction in which the grooves are formed. Specifically, the direction of the formation of the divided regions "and the grooves of Nai is: forming the divided regions and y4 The direction of the ditch is orthogonal to each other. The grating M responds to the direction of the grooves and grating constants of each of the divided areas yi, h, W, and h in order to diffract and divide the light returned by the incident disc 2 into four parts and guide the light receiving part. Photodetector 91 for the main beam. The grating 79 is formed as a hologram element by a hologram pattern specific to the etching process. In addition, when using a holographic element — a surface relief hologram, or a blazed hologram to improve diffraction = 〇 Furthermore, the composite optical element 62 can also be designed to have a reflective surface inside so that the reflective surface is used. The freedom of optical design is improved by the curved optical path

Furthermore, since the composite optical element 62 is formed so that the incident angle of the light incident from the optical disc 2 incident on the division 稜鏡 M is formed on each side of the division 稜鏡 78. In the following, the inclination angle of each plane dividing 稜鏡 78 will be 45. In the following, in order to prevent the incident returning light from entering the total reflection condition, the refraction angle can be increased. Therefore, the beam spot interval of each divided returning light can be separated, and each of the main beam photodetectors 91 can be enlarged. Photodetector for interval and main beam division

The interval between 91 and the side beam light detection n 92, 93 can relax the combined precision of the optical pickup device 3. The optical disc device provided with the optical pickup device 3 having the above-mentioned optical system 60. The light emitted from the self-reflection device 2 is controlled by the rotator circuit 10 based on the focus error signal and the tracking error signal detected by the optical pickup device 3. The signal to the two-axis actuator of the optical pickup device 3 is driven by the objective lens to change the focus direction and the tracking direction, respectively. The focus light is focused via the objective lens 34: on the required recording track of disc 2. Then, the optical disc device 1 performs demodulation processing and error correction processing of the -33- 200306548 signal read by the signal path 12 and the error correction circuit ㈣ optical pickup device 3, and then inputs the signal from the interface 14. The following is provided with The optical disk device 1 ′ of the optical pickup device 3 of the optical system 60 described above will explain the optical paths of the emitted light and the returned light in the optical pickup device 3 with reference to the drawings. Fig. 1 & When the information is reproduced in 2a, the light emitted from the light source 61 is blocked by the first light-shielding plate 64. Unnecessary light is blocked, and only the effective light beam is incident on the composite optical element 62, and is divided by the first diffracted light thumb 75 of the composite optical element 62. 3 shots including 0th order light and ± 1st order light = the second light diffraction grating 76 ′ of the 3rd beam emitted by the knife J passes through the composite optical element α and is condensed by the objective lens 34 The recording surface 2a of the optical disc 2. The light emitted from the recording surface 2a of the optical disc 2 is diffracted by the second diffraction grating 76 of the composite optical element 62 into the optical path toward the third surface, +1 times of light: Is incident on the third diffraction grating 77.

A diffracted light thumb 7 6 + 1 + two female sons and daughters are poor, and the first hunter is reflected and diffracted by the second brother diffraction grating 77, and the human light is incident on the top angle of tiller 78. The -1 times of light incident on the top angle of the regular quadrangular pyramid that is divided into clumps are incident on the peripheral surfaces of the regular quadrangular pyramid, respectively, and t is refracted in different directions, and is divided into 4 pieces of reflected light. Light plate 65 blocks unnecessary light

Each light receiving area I of the phase detection beam is detected by light I: The diffraction light diffracted by the diffraction grating 77 is incident on the split prism ^, as shown in FIG. 17B, the objective lens 34 and the optical disc 2 When the recording surface h is located at two positions, diffracted light forming a substantially circular shape is incident on the vertex of the division 稜鏡 78. -34- 200306548 In addition, when the diffracted light is incident on the top angle of the segment 稜鏡 78, as shown in Figure 7A, when the objective lens 34 and the recording surface 2a of the disc 2 are too close, the objective lens 34 deviates from the in-focus position. Therefore, due to the astigmatism generated by the diffracted light passing through the composite optical element 62, a diffracted light with a long axis forming the upper right of the figure is incident on the top angle of the division 稜鏡 78. When the diffracted light is incident on the top angle of the division 稜鏡 78, as shown in FIG. 17c, when the objective lens 34 is too far away from the recording surface 2a of the optical disc 2, the objective lens 34 deviates from the focal position. The astigmatism generated by the composite optical element 62 is incident on the top angle of the division 稜鏡 78 with a long axis forming an elliptical diffracted light in the upper left of the figure. At this point, in the state where the objective lens 34 is deviated from the in-focus position, the technical light is incident on the top corner of the division 稜鏡 78, and the phases of the division 稜鏡 78 are in phase with each other: two sets of peripheral surfaces X1 ′ X3 and peripheral surfaces X2 On X4, it is divided into most of the incident diffracted light on the peripheral surfaces of the-group and very little incident diffracted light on the peripheral surfaces of the other group. That is, as shown in FIG. ΠA, the elliptical diffracted light incident on the mirror 78 is formed. The majority of the diffracted light is incident on a set of opposite peripheral surfaces Xi, and a small part of the diffracted light is incident on the -group opposite The respective peripheral surfaces χ2, χ3. In addition, as shown in Fig. M, the elliptical diffracted light incident on the division 稜鏡 78, most of the diffracted light is incident on a group of relatively long time, and a very small part of the diffracted light is incident on the two opposite groups of X ; 'X4 The self-light 1 of the 0th light divided by the first diffraction grating 75 χ3 The second diffraction grating 76 is diffracted to form -1 light, and the light of the second mouth u is used to divide the 稜鏡Weeks of 78 :: Light is incident 3 and refracted in different directions -35- 200306548 Because of this, it is divided into 4 pieces of returning light 'and is incident on the main beam photodetector 9 1 Each light receiving area a2, dagger, C2, ^. Therefore, as shown in FIG. 18A and FIG. 18C, the two light receiving areas a2, e2 and the light receiving areas h, 4 of the two sets of the main beam measuring device 91 facing each other are changed. And the amount of light received by each light receiving area of the other group becomes smaller. That is, when the elliptical diffracted light shown in FIG. 17A is incident on the division 稜鏡 78, the main beam photodetector 91 is as shown in FIG. 1δA *, and the respective light-receiving regions ^ 'c2 receives a larger amount of received light' and In contrast, each light-receiving area receives 2: the amount of light received is reduced. The elliptical diffracted light as shown in FIG. 17C is incident on the dividing edge. • On the 78th day, the photodetector 91 for the main beam receives light as shown in the area ™, and the amount of light received by each C2 becomes smaller. When the circular diffracted light shown in FIG. 17B is incident on the top angle of the division 稜鏡 78, as shown in FIG. 18B, the main beam photodetector 91 is opposite to each light receiving area a, and each light receiving area h, Cb. Each received light amount is equal. 2 Therefore, in the photodetector 91 for the main beam, each light receiving area ... D, C, and the output detected by each is Sa2, called,%, when called, the focus error 2 4 Lu No. FE can be shown as the following formula 22 Calculation. , (22) FE = (Sa2 + Sc2). (Sb2 + Sd2) That is, when the main beam photodetector 91 is at the focus position of the objective lens 34 and the recording surface 2a of the disc 2 by The focus error number FE calculated by Equation 22 is zero. In addition, when the main beam photodetector reads the objective lens 3 and the recording surface 23 of disc-36-200306548 2 is too close, the focus error signal FE is positive and the objective lens 34 is recorded from the first disc 2 When the surface is too far away, the focus error message is negative. As described above, the photodetectors for main beams of the light receiving section 63 are incident on the respective light receiving regions a2 ', respectively. 2, & output of each beam spot to obtain a focus error signal FE and a reproduction signal. Each side beam of a group uses light detectors 9 2 and 9 3 to detect the respective amounts of light received by the light reflected from the optical disc 2 among the primary light divided by the first diffraction grating 75, and calculates these light values. The difference of each output 'is obtained to obtain the tracking error signal TE. As described above, the optical disc device controls the lens driving mechanism based on the focus error signal and the tracking error rank signal TE 'servo circuit 1Q obtained by the optical pickup device 3 having the optical system 30 or the optical system 60. Xiao By changing the driving direction of the object money to the direction of "tracking and tracking", the emitted light is focused on the recording surface 2 & of the optical disc 2, and information is reproduced from the optical disc 2. As described above, the optical pickup device 3 having the optical system 30 of the optical disc device 1 of the present invention has a composite optical element 32, which is provided with: a second diffracted light thumb 46 diffracted from light; and The second light emitted by the second + 1 time is used as the return light, and the third diffraction grating 47 that diffracts the return light further; even if the self-receiving light is caused by the ambient temperature change-the light emitted by the carved element 31 The fluctuation of the oscillation wavelength can still be guided appropriately: the position is compared with the system, the use of no additional parts can make the focus error obtained. Therefore, the reliability of the optical pickup device signal FE with a simple structure of the optical disc device 1 and the previous optical coefficient amount improve. With optical disc device! Optical pickup device with optical system 60] With -37- 200306548 composite optical element 62, it directly bites the right prostitute / yes. Diffraction of light from the second disc, the second pill The diffraction grating 76 will use the first junction to return the light, and further advance the d—'Γ diffraction +1 times of light as the second diffraction grating 77 of the M return light; and will borrow == 射The -1 times of light diffracted by the grating 77 is used as the returning light, and the light beam at the exit port is divided into four parts | ^ 7 2 knife port mirror 78, even if the ambient temperature changes :::: :, The exhaust change of the emitted light from 1 can still be guided. Therefore, the optical disc device is equipped with a Umbrella, and compared with the previous system. It uses a simple structure of the optical fiber without adding parts. , The reliability of the obtained focus error # # 〇FE can be improved. F set 3 is caused by: optical disc I set 1 is provided in the optical pickup light r composite optical element 32 having an optical system 30 to separate the emitted light and the returned light, and to correct the wavelength variation of the emitted light emitted from the body element 31 The function of changing the optical path, Min Bu μ Dingsha Group 1 exhibition leader < IX Therefore can keep the number of optical parts to the minimum necessary, interspersed optics Li Xu Xi Shipo, Sheng Yikou Γ first 0 structure k 'promote Miniaturize 'and reduce manufacturing costs. Therefore, the optical of the optical disc device 1 can be obtained, and the composite optical element 32 can be used: "The learning system 30 has reliability. In order to reduce the production cost, reduce the manufacturing cost, and improve the optical disc device 1 which is damaged in the optical pickup device 3 with the optical system 60 'only the composite optical element 62 separates the emitted light and the returned light, and corrects the emission from the light source 61 The change of the optical path caused by the change in the wavelength of the emitted light can keep the number of optical parts at a high level, and the structure of the optical system 60 can be interspersed to promote miniaturization and reduce manufacturing costs. 38 · 200306548 Therefore, the wind composite optical element 62 ′ in the optical pickup device 3 of the optical disc device 1 can improve productivity and reduce the reliability of the production + system 60. Cost and increase the use of the optical disc device 1 with the optical system 30 When the light system is formed using the integrated light source and the light receiving element, the device 3 uses an optical unit, which can further reduce parts: the cost of the light-body component is reduced, and the manufacturing of the optical disc I is set to 1 by having Optical system 60 optical combination optical element 62, the composite optical element has a split beam with a complex light 78 ', and the main beam with a crying-returning split beam The comparison of the forms is based on the division of the beam back on the optical path: the division line is divided by the 4 beams of the back beam divided by the division 稜鏡 78. Therefore, each of the light receiving areas of the test line 91 &, dagger, d2 Keeping the required fine yield at the division position of the photodetector for the wide main beam ^ wide main beam, etc., and putting the second device 1 can reduce the main beam of the optical pickup device 3: 1 caused by the detection In the manufacturing steps of the optical pickup device 3, it is easy to adjust the position of the main beam photodetector 91, which can improve the reliability of the obtained focus error signal FE. Furthermore, the optical disc device 1 has an optical system 60. The optical pickup device 3 has a first light shielding plate 64, which only directs the light beam V emitted from the light source 61 toward the composite optical element 62, and blocks unnecessary light incident into the composite optical element 62. Reduces the scattered reflection of the diffused light in the composite optical element 62. The optical disc device 1 has a second light shielding plate 65 by an optical pickup device 3 having an optical system 60, which only returns the light transmitted through the composite optical element 62 to -39. -200306548 the effective light beam is directed to the light receiving section 63, and The “unnecessary light incident on the light receiving unit 63” can improve the reliability of the light detection level of the light receiving unit 63. In addition, the optical pickup device having the optical system 6 of the optical disc device 1 is shown in FIGS. 11 and 12, It is not limited to having the first light-shielding plate 64 and the second light-shielding plate 6 5 ′. For example, a light-absorbing coating may be coated on the surface of the composite optical element 62, and an opaque film may be vapor-deposited on the surface of the composite optical element 62, or The surface of the composite optical element 62 is roughened to block unnecessary light. The optical disc set 1 is used to obtain the focusing error L number FE in the optical pickup device 3 described above. The so-called astigmatism method is used, but also Other detection methods such as the Foucault method can be used. Moreover, when the optical disc I is set to 1, it is not easy to constitute one element of the composite optical element and the composite optical element 62 as described above. Of course, by forming each optical element to form an optical system with the same configuration as described above, of course, the same can be obtained. Features. In the following description, a configuration example of the optical pickup device 3 not including the composite optical element 32 and the composite optical element 1 but having an optical system in which each optical element has the same arrangement as described above is described. In addition, the optical pickup device 3 k with the above-mentioned combined optical element 32 or composite optical element, and an optical system having a correction optical path variation, but the optical pickup device shown in the following example is an optical system having a correction astigmatism Example: Shi Baixian, the optical pickup device 3 of the first example, as shown in FIG. 19, has: an optical system 100 that reproduces information from the optical disc 2; Lens drive mechanism not shown. For the optical pickup device 3 with optical system 100 and 1, and the optical pickup device 3 with optical system 3G or 60, note the shared -40-200306548 The symbol and its detailed description are omitted. The optical pickup device 3 is right-handed, and there is an optical system! 〇〇 According to the order of the optical path, it has a light source 101, which emits 4, k π, and 9 to the optical disc 2; The diffraction grating 102 is configured to emit eight 4 Α 6 and nine blade brakes emitted from the light source 1 0 1 into three parts; the beam splitter 1 03 is divided into three by the diffraction grating 102. The emitted light reflects and The light returned by the optical disc 2 passes through the aperture 1 〇4, which is a light beam that will be reflected by the beam splitter 1 〇3, and the numerical aperture NA of the & 对 objective lens, 05, It splits the light emitted from the disc 2 through the beam splitter and divides it into 4 by focusing the output light condensed by the open σ aperture 1G4 on the recording surface 23 of the disc 2 and splitting it into 4 Bangba · η β 'σ knife, and light receiving unit 107, which receives the reflected light separated by the segmented 稜鏡 1 06. The light source 1 0 1 has an emission wavelength of about 780 nm from the first point 101a of Sumotome. The semiconductor laser of the laser light. The diffraction grating m is a diffraction element that divides the light emitted from the light source 101 into 0th order light and 1st order of the first temple. The scattered direction of the emitted light corresponds to the optical disc 2 The direction of the recording track. To obtain the tracking error signal TE in the optical system, the so-called Dpp (differential push-pull) method is used, and the light receiving section] π receives the light divided by the diffraction grating ⑽ once. The eight-beam splitter is a parallel flat member that includes a first surface 103a and a second surface and is transparent. The first surface 103a and the second surface 配置 are arranged in such a way that the light emitted from the light source 101 has a specific angle, and the first surface 103a reflects the light emitted from the light source 101 and is guided to the disc 2 side. And the reflected light reflected by the optical disc 2 is transmitted through the first surface 103 and the first surface I & -41-200306548 and guided to the division 稜鏡 106. The knife beam state 103 passes the light reflected from the optical disc 2 to pass ， On the returning light incident on the eight-mirror 106, it is only given; the cutting edge „, χ inch 疋 li to keep away. Beamsplitter M3H is adjusted from the light source 1 0 1 shot by ten people, and you can adjust the defocus of disc 2 by mistake. In order to easily adjust the beam splitter 103 at this time, and L% Shi Guangdi face 03 & there is reflected from the light Mae] η α out, and make the light reflected from the disc 2 half transmitted Mirror surface. In addition, a diffractive element that corrects the amount of astigmatism of the light returned from the optical disc 2 is provided on the second side 103b of the music of the knife ^ 103, and the astigmatism of the light returned through the beam splitter 10 is suitable. For focus adjustment. This month, specific holographic patterns form holographic elements. In the case of using two pieces of Chuan Wang's heart, it is also a surface relief type hologram. "To refine the hologram to increase the aperture around the aperture 104 (opening)) r-vertical 勹 P to form a 4-inch fixed numerical aperture to combine light 'is arranged on the remaining axis of 1 M with beam splitting. M3 The light-to-object lens 1 0 5 reflected by the light surface 1G3a is composed of at least one convex 1U convex lens, and is emitted from the light source 101 and is emitted by the opening aperture 104 and the umbrella M mountain T g comes out of the light. The light is condensed on the disc 2. As shown in Figure 20 and Figure 21, the public treasure f Λ C \ r DJ spear mirror 1 06 forms a roughly regular quadrangular pyramid shape, and is used for transmission. The beam returning beam of the beam splitter 103 is located near the home, point, or focal point, and the center of the beam of returning light is arranged so as to be incident on the center of the vertex angle of the regular quadrangular pyramid f. The split beam 106 is located through the beam splitter 103. Shoot the heart first, and divide the return light into four parts. -42- 200306548 Light cone division 稜鏡 106 is made by the under-incidence of the three beams divided by the diffraction grating 102 into the top corner. In addition, the division 稜鏡 〇6 is faced with the bottom of the positive four corners and is divided into three times by the diffraction beam i 〇2. The light and optical axes are arranged orthogonally. The blade 1 06 is formed by injection molding a resin material. In addition, the material forming the division 1 06 is not limited to a resin material, and a transparent material such as a glass material may be used. Optical optical materials, and furthermore, the material structure can be locally changed by the combination of such optical materials. As shown in the figure of Fig. 22, the cross light unit 107 has the following functions: _2, which is divided by the diffraction grating ⑺2. The main beam is a square-shaped main beam for a light detector 111; and one of two side beams, each of which receives a side beam of ± 1st order divided by the diffraction grating 102, is used for a side beam of a roughly band shape Photodetector 112, ιΐ3. Light receiving section 107-placed at a position corresponding to each of the reflected light divided by the blade # 彳 稜鏡 i Q6. The light receiving port P 107 is provided with a centrally-shaped, roughly square main beam The photodetector 111 is provided with a photodetector m, ⑴, which is a side beam with a roughly square group on both sides of the photodetector for the main beam. The photodetector for the main beam of 07 is divided into four equal parts by a group of lines orthogonal to each other. Light-receiving area ^, b3, ..., 7. Each light-receiving area or a3 b3 'e3' d3 irradiates each of the returned light divided into four parts by the segmentation and division. The side light part of the light-emitting part 10 7 At the end of Takimachi, the photon states 11 2 and 11 3 respectively have the incense that is divided into two halves by the dividing line, and then the E domain, f3, and the light receiving areas g3, h3. Within each light area e3 ' Zhao 4kL rfe…, a single beam of light corresponding to the primary light of the soil divided by the diffraction grating 102, and the light returned from the disc 2 is irradiated within each light receiving area g3, h3 -43-200306548 corresponding to the The other side of the light that has been divided by the radiation grating 102 from the ± 1 order of light and returned by the chirped light 2. The lens driving mechanism provided in the optical pickup device 3 has: a lens holder holding the objective lens 105; supporting the lens holder can be parallel to the focusing direction parallel to the optical axis of the objective lens and perpendicular to the optical axis of the objective lens 05 A bracket support member that is displaced in the two-axis direction of the tracking direction; and an electromagnetic drive portion that changes the lens holder drive to the two-axis direction by electromagnetic force, but it is not shown in the figure. The lens driving mechanism makes the objective lens 1 according to the focus error signal detected by the main beam photodetector of the light receiving unit i 〇7 and the tracking error signal detected by the side beam photodetectors 112 and ι3. The 5 driving variable is located in the focusing direction and the tracking direction, so that the emitted light is focused on the recording surface of the optical disc 2. Recording on track 0. An optical disc device 1 having an optical pickup device 3 having the above-mentioned optical system 100. The optical pickup device 3 determines the hue and tracking error signals based on the optical pickup device 3's focus detection by the light emitted from the optical disc 2. From the servo circuit, the control signal is output to the two-axis actuator of the optical pickup device 3. The objective lens 105 is driven to change the focus direction and the tracking direction, and the emitted light is combined via the objective lens 105. Focus on the required recording track of disc 2. Then, the optical disc device 1 performs demodulation processing and error correction processing on the digits read by the optical pickup device 3 through the demodulation circuit 2 and the error correction circuit 13, and outputs a reproduction signal from the interface 14. In the following, the optical paths of the emitted light and the returned light in the optical pickup 100 having the optical system 100 described above will be described with reference to the drawings. -44- 200306548 When the optical disc device 1 reproduces information from the recording surface 2a of the optical disc 2, as shown in FIG. 19, the light emitted from the light source 1 0 1 is divided by the diffraction grating j 〇2 into the light and soil 1 time. 3 beams of light. The emitted light, which is divided into three beams, is reflected by the first surface i03a of the beam splitter 103, condenses into a specific numerical aperture by the opening aperture 104, and is condensed by the objective lens 105. On the recording surface 2a of the optical disc 2. The light returned from the recording surface 2a of the optical disc 2 is refracted by the first side 1 of the beam splitter 103 and passed through the beam splitter 103 and refracted by the second side 103b to further correct the image. The reflected light corresponding to the 0th order light divided by the diffraction grating 102 is incident on the top angle of the division chirp 106. The reflected light incident on the apex of the regular quadrangular pyramid of the division 稜鏡 106 is refracted in different directions by being incident on the peripheral surfaces of the regular quadrangular pyramid, respectively, and is divided into four reflected light. Each of the light-receiving regions a3, b3, and C3 of the main beam photodetector ⑴ irradiated to the light-receiving unit 107. In addition, one side corresponding to the primary light transmitted through the beam splitter 103 by the primary light divided by the diffraction grating 102 is irradiated to each of the side beam photodetectors 112 of the light receiving unit 107. The light-receiving areas es, f3, and the other are irradiated to the light-receiving areas g3, h3 of the side-beam photodetector 113 of the light-receiving section 107, respectively, and the reflected light transmitted through the beam splitter 103 is incident on the division The top of ===, as shown in FIG. 23B, the objective lens 105 is facing the recording surface of the optical disc 2. Located at the position of the sun guard, the apex angle of the division 稜鏡 〇 06 is incident with a return light forming a substantially circular shape. In addition, when the reflected light is incident on the apex angle of the division 6106, as shown in FIG. 23A, when the recording surface of the objective lens 105 and the optical disc 2 are too close, the objective lens-45- 200306548 lens 1 0 5 is out of focus, so the astigmatism caused by the returning light passing through the beam splitter 103 enters the ellipse of the upper right in the figure with the long axis incident on the angle of division of 稜鏡 i 06. Light. When the τ incident light is incident on the top angle of the segmentation 稜鏡 106, as shown in the picture, when the objective lens 105 is 2 m away from the recording surface of the disc 2, the objective lens 偏离 deviates from the focal position 'hence'. Generated by the beam splitter ⑼ at the top corner of the segment 稜鏡 106, the ancient light &, Moonbeam is incident on the long axis to form a circular return light at the upper left in the figure. Therefore, 'in the state where the objective lens 105 deviates from the in-focus position, when the reflected light is incident on the top angle of the division 稜鏡 106,' the two sets of peripheral surfaces X5, x7, and perimeter of the division 稜鏡 106 that are opposite to each other. On the planes X6 and X8, it is distinguished that most of the incident light is incident on the peripheral surfaces of one group, and very little incident light is incident on the peripheral surfaces of the other group. That is, as shown in FIG. 23A, a rounded reflecting light incident on the splitter mirror 106 is formed, and most of the reflected light is incident on a set of opposite peripheral surfaces ~, and the reflected light A very small part is incident on a set of opposite circumferential centers, &. As shown in FIG. 23C, most of the reflected light incident on the segment 稜鏡 _, which forms the ellipse, is incident on the peripheral surfaces of a group &, and a small part of the incident light is incident on A set of relative faces centered around. The 0th-order light divided by the diffraction grating 10 in the light returned from the optical disc 2 is incident on the respective circles δχ5, χ6, X ″ of the division 稜鏡 106 and refracted in different directions, so it is divided into 4 The light beams are returned and incident on the respective light receiving regions of the main beam photodetector 111 of the light receiving unit 111, q, ^. Therefore, as shown in FIG. 24A and FIG. 24C, the main beam Photodetectors η -46- 200306548 The two groups of light receiving areas opposite to each other, the amount of light received by each light receiving area of each of the light receiving areas b3, one of the seven groups becomes larger, and the light received by each light receiving area of the other group That is, when the elliptical retro-reflection light shown in FIG. 23A is incident on the division 稜鏡 106, the main beam photodetector U1 is shown in FIG. 24A, and the respective light receiving areas a3'c: Accept The amount of received light is increased, and the amount of received light is smaller than that of each light receiving area. As shown in Figure 2 3c, the elliptical reflected light is incident on the split prism 1. On the 06th, the main beam uses a light detector. i 丨 丨 As shown in FIG. 24c, the amount of light received by each light receiving area b3, d3 becomes local, and In contrast, the amount of light received by each light-receiving area a3 ′ 4 becomes smaller. When the circular reflected light shown in FIG. 23B is incident on the apex angle of the division 稜鏡 106, the main beam light detection ϋ1η is shown in FIG. 24β, In contrast, each light receiving area ^, h is equal to each light receiving area d, and each light receiving amount is equal. Therefore, the main beam is detected by the light detector iii, and each wheel ς is detected in each light receiving area ^ h 'd3. Cu When r is Sa3, Sb3, Sc3, or Sd3, the focus error signal FE can be calculated as shown in Equation 23 below. (23) FE- (Sa3 + Sc3) «(Sb3 + Sd3), which is 'for main beam' The photodetector is located when the objective lens 105 is located at the in-focus position on the recording surface 2a of the optical disc 2. The focus error signal FE calculated by the formula 23 is 0. In addition, the main and private beams are m, and the photodetector 111 is used for the beam. When the objective lens 105 and the recording surface 2a of the optical disc 2 are too close, the error signal FE of ^ ^ I is taken to be positive, and the recording of the objective lens 105 from the optical disc 2 is & The focus error signal FE is negative. As described above, the light receiving section 107 < the main beam photodetector 111 uses -47, 200306548 light receiving area & 3 , w The output of each beam point is used to obtain a focus error signal and a reproduction signal is obtained. ^ The side beams of the outer group use light detectors 112 '113 and each of the light receiving areas e3, f3, g3, h3 to receive the divided The gratings 102 are diffracted in each of the 4 times of the light returned by ± i order of light. Therefore, each of the light receiving areas e3, f3 '§3' h3 of the 'side beam photodetector ⑴' 分别 is detected as When Se3, Sf3, Sg3, Sh3, the tracking error signal TE is calculated as shown in Equation 24 below. TE = (Sa3 + Sc3)-(Sb3 + Sd3) -a ((Se3-Sf3) + (Sg3-Sh3)) · · · (24) Eight optical systems constructed as above The astigmatism can be appropriately corrected by the second surface 103b of the beam splitting 103, and the reflected light can be divided into 4 parts by the division 稜鏡 106. Therefore, the returned light can be appropriately guided to each light receiving area of the light receiving section 107. . Secondly, as shown in FIG. 25, the second example of the optical pickup device 3 includes: an optical system 12o that reproduces information from the optical disc 2; and the optical system 12o is provided with a driving displacement of the objective lens described later, which is not shown in the figure. Lens driving mechanism. In the following, the optical pickup device 3 having the optical system 20 is adopted. However, the common structure with the optical pickup device 3 having the optical system 100 is denoted by common symbols and detailed explanations thereof are omitted. The optical system 1 20 of the optical pickup device 3 has, in the order of the optical path, a light source 1 0 1 ′ which emits laser light onto the optical disc 2 and a diffraction grating 10 02 which divides the emitted light emitted from the light source 101. Into 3 parts; beam splitter 123, which is -48- 200306548 knife quilt, vo-ray grating] 02 divided into 3 parts of the emitted light and the light returned from the disc 2 light & 'open σ aperture! 〇4, which focuses the output light separated by the beam splitter 成 into a specific numerical aperture NA, · objective lens 105, which focuses the output light condensed by the opening aperture 104 On the recording surface 2a of the optical disc 2; the division prism 106 'divides the light returned from the optical disc 2 through the beam splitter 123 into 4 parts; and the light receiving unit 107 receives the divided prism ι. The separated light returns to light. The beam splitter 123 is a parallel flat plate member including a first surface 123a and a second surface 12 supplemented by light transmission, and the first surface and the second surface 123b have a specific angle to the light emitted from the light source 101. It is configured to reflect the laser light emitted from the light source 101 with the first surface 123a, and guide the laser light to the side of the optical disc, and make the reflected light reflected by the optical disc 2 pass through the first surface and reflect with the second angle, and then pass through the first One side 123a leads to division 稜鏡 106. The second surface 123b of the beam splitter 123 forms a total reflection surface. The second surface is formed by, for example, a vapor-deposited reflective film, and the total reflection reflects light. The beam splitter 123 passes the light reflected from the optical disc 2 and imparts only a certain amount of astigmatism to the light reflected from the incident prism ⑽. By adjusting the position of the beam splitter 123 in the optical axis direction of the emitted light from the light source 101,

Defocus the entire pair of discs 2. I At this time, on the first surface 123a of the beam splitter 123, a semi-reflecting mirror surface that reflects the light emitted from the light source 101 and transmits the light returned from the optical disc 2 is transmitted. In addition, a diffraction element that corrects the amount of astigmatism of the light returned from the optical disc 2 is provided in the emitting area of the first surface 123 & of the light returned from the optical disc 2 through the beam splitter 123. The amount of astigmatism of the return light is corrected in a manner suitable for focus adjustment-49-200306548. Such a diffractive element can also be destroyed by etching a specific hologram.) In the case of a holographic element, it should be a surface relief type hologram. It can also be a blazed hologram to improve diffraction. effectiveness. As shown in FIG. 20 and FIG. 21, 'divide 稜鏡 106 to form a roughly regular quadrangular pyramid material' and pass through the focal point of the returned light or near the focal point of the beam splitter 123, and the center of the incident light enters the vertex angle of the regular quadrangular pyramid. Central configuration. "Fenbao", mirror 106 is located on the optical path of the light returned through the beam splitter 123, and splits the light into 4 parts. The optical disk device is provided with the optical pickup device 3 having the optical system 120 as described above. 1 According to the focus error signal and tracking error signal detected by the optical pickup device 3 by the light emitted from the optical disc 2, a control signal is output from the servo circuit 10: The two-axis actuator of the optical pickup device 3 The objective lens 105 is driven and intersected in the focusing direction and the tracking direction, respectively, and the emitted light is focused on the required recording track of the optical disc 2 through the objective lens 1. Then, the optical disc device uses the ^ demodulation circuit 12 And the error correction circuit 13 performs demodulation processing and error correction processing on the signal read by the optical pickup device 3, and the interface 丨 4 rounds = reproduction signal. Hereinafter, the optical pickup having the above-mentioned optical system 12 will be described with reference to the drawings. The optical path of the emitted light and the returned light in the j set. When the optical disc device 1 reproduces information from the recording surface 2a of the optical disc 2, as shown in FIG. 22, the emitted light emitted from the light source 1 〇1 is diffracted by the diffraction grating 1. 02 is divided into 0 times light and 3 beams of primary light. The emitted light that has been divided into 3 beams is reflected by the first surface i23a in beam splitting state 123, and is condensed into a specific numerical aperture by the opening aperture 104, and The objective lens 105 is focused on the recording surface -50-200306548 2a of the optical disc 2. The light returned from the recording surface 2a of the optical disc 2 is refracted by the first surface i23a of the beam splitter 123 and passes through the beam splitter 123. 'It is reflected by the second surface 12 and corrects the amount of astigmatism in an emission area different from the incident area of the first surface 123 a and transmits it, corresponding to the return of the 0th light divided by the diffraction grating 1 02 The light is incident on the apex angle of the division 稜鏡 106. The reflected light incident on the apex angle of the regular quadrangular pyramid of the division 〇106 is refracted in different directions by incident on the peripheries of the regular quadrangular pyramid, respectively. Divided into 4 pieces of reflected light and irradiated to the respective light receiving areas h, eg, 7 of the main beam photodetector lu of the light receiving unit 107. In addition, it corresponds to ± 1st order light divided by the diffraction grating 102 One side of the reflected light transmitted through the beam splitter 3 123 is irradiated to each side of the side beam photodetector U2 of the light receiving unit 107. Areas e3, f3 'The other side irradiates the respective light-receiving areas of the side-beam photodetector 113 of the light-receiving unit 107, respectively. The optical pickup device having the optical system 12o structured as described above is the second one of the beam splitter 123. One side 12h evening Μ 山 r said that the diffractive elements in the mouth and the field are suitable, and the light can be returned to the light by dividing the 稜鏡 106 :: The light is appropriately guided to the light receiving areas of the light receiver. / 、 人 # The optical pickup device 3 of the second example is shown in FIG. 2 and the optical system 13 of the disc 2 reproduces the information, and the optical system ": Gu Zi first described the displacement of the objective lens drive / ,, /, after having " 夂 1 The optical pickup device 3, 1 having an optical system 130 is not shown on the circle. Learn System 1 below. . ::: 二 有光 shared by the optical pickup device 3 and its detailed description is omitted. ° // Predicted by the optical pickup device 3 with the number, and the dead 130 has the order of the first order ... -51-200306548 source 101 ', which emits laser light onto the optical disc 2; the diffraction grating 102, It splits the light emitted from the light source HH into three parts; the beam splitter 133, which is separated from the diffracted light by the book 1 〇 八八 堂 丨 A, q, Youshu 丨 ϋ2 knife brake into 3 parts Optical path length of emitted light and light returned from disc 2; opening φ! n / 1 ^ ^ Nineteen circles 104, which condenses the light emitted by the beam splitter 133 into a specific numerical aperture NA; for the objective lens ⑽, which condenses the light emitted by the opening aperture 104 Light on the recording surface 2 & of the optical disc 2; division 稜鏡 106, which divides the light returned from the optical disc 2 through the beam splitter 133 into 4 parts; and light receiving objects, which are divided into 稜鏡The reflected light separated by 106. The beam splitter 133 is composed of the Chu—3 · 罘 side 133a; the first surface 13 parallel to the first surface 133a, and between the first surface 133 & and the second surface 13 3b, the emitted light The shaft is inclined only by the third surface 133 at a specific angle. A fourth surface n3d that is a direct father of the first surface and the first surface 133b; and a fifth surface 133e that is substantially parallel to the third surface and has a light transmitting member. The beam splitter 配置 is arranged such that the first face ⑴ & and the second face 133b are approximately orthogonal to the light emitted from the light source ，, so that the light emitted from the light source 101 passes through the first face i33a and is reflected by the third face 133c. The sub-transmission passes through the fourth surface n3d to the side of the optical disc, and the reflected light reflected by the optical disc 2 passes through the fourth plane n3d and the third surface ^ rainbow, and is reflected by the fifth surface 133e, and the sub-transmission passes through the _th surface 13; Shoot out the area and guide the split prism 1 06. The knife beam is 133. The five sides of the prism enter MG * ^ to form a total reflection surface. The five sides of 133e, such as a strip-shaped reflective film, are shaped like dots,. ^ FREE ΐ »8 ~ 成 While total reflection reflects back light. The beam splitter 133 passes through the light reflected from Duoshi T ^ Λ,, Yuan Yuan 2 and imparts only a certain amount of astigmatism to the reflected light incident on the split prism 106. The beam splitter 133 adjusts the position of the optical axis direction of the light emitted from the light source 调 by adjusting -52- 200306548 to adjust the defocus of the pair of optical discs 2. "Early two easy to adjust" Then on the third surface 133 of the knife beam 133, there is a semi-reflecting mirror that reflects from the light source 1 and exits, and allows the light returned from the optical disc 2 to pass through. This time, the points are: a diffraction element that corrects the amount of astigmatism of the light returned from the optical disc 2 is provided in the shooting area of the 133-th surface 133a of the light returned from the optical disc 2; transparent; The amount of astigmatism of the return light of 33 is suitable for the focus adjustment =. This kind of diffractive element can also be used, and the holographic pattern with a specific name is formed from 1 to H. When using a holographic element, it should be a surface relief-type king interest chart, or it can be a blazed hologram to improve the diffraction efficiency. . As shown in FIG. 20 and FIG. 21, the division 稜鏡 106 is formed as follows: and: near the focal point of the light returned by the beam splitter 或 or near the focal point, the center of the first shot incident on the center of the vertex of the regular quadrangular pyramid Way configuration. The division prism 106 is located to divide the light into four parts by the beam splitter 133. In the first private matter, Ya set the shot back to the monument with the optical pickup device 3 having the optical system 130 as described above. According to the optical pickup device 3, the focus detection by the light shot back from the optical disc 2 is wrong. And tracking error signals, the control signal is output from the feeding circuit 10 to: the two-axis actuator of the pick-up device 3, and the objective lens 105 is used to drive the Ai located in the focusing direction and the tracking direction. The objective lens 105 focuses on the required recording path of the optical disc 2. The optical disc device i uses the signal demodulation circuit 12 and the error correction circuit 13 to perform demodulation processing and error correction processing on the number read by the optical pickup device 3, and then reproduces the self-reproduced signal from the media: Optical paths of the emitted light and the returned light in the optical pickup-53-200306548 device 3 having the above-mentioned optical system 13. The optical disc device 1 is from the record of the optical disc 2. When the recorded information is reproduced on the recorded surface 2a, the three light beams emitted by the light beam 101 emitted by the light source 101 and the three light beams of ± 1st order, and the light beam 1 are divided into two. Eight walking crying η3, and the light emitted by the y knife brake into three beams passed through the knife port 33 & reflected by the third face 133c, and continued to pass through the fourth face ⑽ 'to focus by opening π aperture m The resulting numerical aperture is focused on the recording surface of the optical disc 2 by the objective lens 105. on. The light from the recording surface of the optical disc 2 through the fourth surface ⑽ and the third surface 133e ′ of the beam splitter U3 is reflected by the fifth surface and is in an emission area different from the incident area of the first surface ⑴ & The astigmatism is corrected and transmitted, and the returning light of the 0th light divided by the diffracted light peach 102 on the other side is incident on the top angle of the division 稜鏡 106. The returning light incident on the apex of the regular quadrangular pyramid which is divided into 稜鏡 106 is refracted in different directions by being incident on the peripheral surfaces of the regular quadrangular pyramid, respectively, and is divided into four retroreflected lights. The main beams of the main beam irradiated to the light-receiving part ι07 are each received by the photodetector ", h, seven. Corresponds to the transmission of the ± 1 order light divided by the diffraction grating 102 through the beam splitter i33 The square of the return light is irradiated to each of the light receiving areas of the side beam photodetector U2 of the light receiving unit 107, f3, and the other side is irradiated to the side beam photodetector 11 of the light receiving unit 107. 3 The light receiving area g3, h3. The optical pickup device 3 having the optical system 130 structured as above can appropriately correct the astigmatism 1 by a diffractive element provided in the exit area of the first surface 133a of the beam splitter 133, and can be corrected by The division 稜鏡 i 〇6 divides the returned light into * sections, so that the returned light can be appropriately guided to each light receiving area of the light receiving section 107. Next, the optical pickup device 3 of the fourth example is shown in FIG. 27, With ... since light-54-200306548: optical system 140 for reproduction information; and after having the optical system i4〇 : Lens driving mechanism not shown in the figure for driving and displacing the objective lens. The following 5 members have an optical pickup device 3 of the optical system 140, but have a common structure for the optical pickup device 3 of the optical system 1GG. Note that the common symbols are omitted and their detailed descriptions are omitted. ', The optical beam of the optical pickup device 3, and the system 14Q according to the order of the optical path: the light source m', which emits laser light onto the optical disc 2; the diffraction grating m, which will The light emitted from Xuanyuan light source is divided into three parts; the beam splitter is ⑷, which directly separates the optical path of the light divided into three parts by the diffraction grating 102 and the light returned from the optical disc 2; the opening π aperture 1G4 It focuses the output light separated by the beam splitter 143 into a specific numerical aperture NA. For the objective lens 105, it focuses the output light condensed by the aperture stop 104 on the optical disc 2. Recording surface ~ upper knife mirror 106 ', which divides the light returned from the optical disc 2 through the beam splitter 143 into 4 parts; and the light receiving part 107, which accepts the light that is separated by the division 稜鏡 ι〇6 The reflected light. / Blade state 143 includes: a first surface 143a; perpendicular to the first surface The first surface 143b of 14 ~, and the third surface connected to the first surface 1 43a and the second surface 143b form a schematic triangular column shape with a transmissive member. The beam bundle I43 uses the first surface 143a. The reflected light emitted from the light source 101 is guided to the disc 2 side, and the reflected light reflected by the disc 2 is transmitted through the first surface 143a, and is reflected by the third surface 143 (:, and is guided through the second surface to the division 稜鏡) 106. The third surface 143 ^ of the beam splitter 143 forms a total reflection surface, and the first surface 143 is formed by a steamed reflective film, etc., and the total reflection reflects light. The beam splitter 143 returns from the optical disc 2 The light passes through, and only a certain amount of astigmatism is imparted to the returning light incident on the split edge-55-200306548 mirror 106. The position of the beam splitter in the optical axis direction of the light emitted from the light source 101, that is, the defocus of the entire pair of optical discs 2. I Easy Tuning At this time, the light emitted from the beam splitter 143 is emitted, and the self-beam: reflected from the light source 1 ° 1. I The semi-reflective mirror surface that allows the light returned from disc 2 to pass through. The second surface 143b of the knife A 143 is provided with a diffraction element that corrects the astigmatism amount, and returns the light through the beam splitter 143. Such a diffractive element can also form a holographic element by etching. When a holographic element is used, the radiation efficiency is high. 'Y-type hologram' can also be a blazed hologram to improve the winding. As shown in Fig. 20 and Fig. 21, split the coffee to form a roughly regular quadrangular shape ... The focus of the returned light of 143 or the vicinity of the focus, The center of the first shot is incident on the top corner of the regular quadrangular pyramid, and the second aperture mirror 106 is located through the beam splitter. The knife beam is divided into 4 parts. , Return to the optical path of the light, and shoot the shot back to the optical pick-up device 3 of the system 140. # 梦梦 置 1 According to the optical pick-up device 3, the disc 4 error signal and tracking error 俨'' Focusing optical pickup device 3 for light detection: ^ Automatically outputs control signals to the focus direction and tracking direction. Shoot = pair: lens 105 drives the focus on the required recording track of disc 2. . Light 2-objective lens 105, combined circuit 12 and error acridine: In the year, the last set is read by the signal demodulation error IT positive circuit i3 to demodulate the light and the error correction process is read by the set 3 The signal outputs a regenerative signal from the interface U. -56-200306548 or below, see the path lengths of the emitted light and the returned light of the optical pick-up garments with the above-mentioned optical system uo in Zhuang Zhao ~, Zhuang & When the optical disc device 1 reproduces the poor sound from the optical recording surface 2a of the optical system 2, as shown in FIG. 26, 'emission from the light source 1 0 1> is prepared + the light emission is divided by the diffraction grating 1 02 into a package. 3 beams of light for 1 time. The output is divided into three beams :: Reflected by 143a, and focused by the aperture stop 104 into a specific numerical aperture #, and is focused on the recording surface 2a of the optical disc 2 by the objective lens 1G5. The light returned from the 0th recording surface 2a of the light 2 passes through the first surface 143 &, 'reflected by the second surface l43c, and corrects the astigmatism sub-transmission in the second surface 143b, corresponding to The returned light of the 0th light divided by the diffraction grating 102 is incident on the top angle of the division chirp 106. The reflected light incident on the apex of the regular quadrangular pyramid of the divided 稜鏡 106 is respectively incident on the peripheral surface of the regular quadrangular pyramid and is respectively folded in different directions, and is divided into four reflected light and irradiated separately. The light-receiving areas of the photodetector lu of the main beam in the light-light unit 107, C, C3, 4. In addition, one of the light beams corresponding to the soil divided by the diffraction grating 102 and transmitted through the beam splitter 1 43 is irradiated to the photodetector 112 of the side beam of the light receiving section 107. Each light-receiving area es, the heart, and the other are irradiated to the light-receiving area center, h3, of the side beam photodetector 113 of the light-receiving section 107, respectively. The optical pickup device 3 having the optical system 140 structured as above can appropriately correct the astigmatism amount by the diffraction element provided in the emission area of the first surface I43a of the beam splitter 143, and can be shot back by the division 稜鏡 106. Since the light is divided into four parts, the returned light can be appropriately guided to each light receiving area of the light receiving section 107. -57- 200306548 As mentioned above, equipped with the first to disk device ... According to the convergence obtained by the optical pickup device 3 having the optical pickup device 3 which is not optical

, Through the servo circuit 1G control; ^ [Γ tracking error signal TE drive becomes in the focus direction and tracking ::: = recording surface-from the optical disc 2 and then ^ 7 to focus the emitted light on the optical disc 2 As mentioned above, the optical disc Device 1 wind, 123, ^, ια, pre-catch device 3 can be beamed by the beam splitter 103, because 4 corrects the astigmatism in a timely manner to correct the shot back from the disc 2 ', so it can control the shooting φ ^ 丨, 4 ^ t ^] 〇β η 乂 6, Ai-shaped, so that the incident light is incident on the segmentation ㈣Μ6, so the reliability of the focus error signal can be improved. The optical strength of the optical disc device 1 can use the same structure as the previous optical pickup device, which can reduce the potential cost and increase the degree of freedom in the configuration of the optical element, making it easy to design the optical system. The optical pickup of device -1 shown in FIG. 19, FIG. 25 to FIG. 26, that is, a division 稜鏡 106 having the light reflected from the optical disc 2 is divided, and the beam is divided by the division line of the photodetector. The form comparison of the beam spot is based on the division of the light beam on the optical path. The main beam is received by the photodetector 1 G7 by receiving the divided light beams divided by the 10 divided by 6. The area \ 3 ° 3 1 is maintained at a specific A small, and the precision required for relaxing the division position of the main beam photodetector is relaxed. Sometimes, the optical disc device 1 can reduce the optical pickup of the main beam photodetector 107 of the optical pickup device 3. It is easy to use the main beam in the manufacturing step of the optical pickup device 3 The position adjustment of the photo detector i () 7 can improve the reliability of the obtained focus error signal FE. -58- 200306548 Miscellaneous: 'The optical disc device 1 can also form the above-mentioned split prism into an octagonal cone. ° In this case, the photodetector for the main beam of the light receiving unit 1G7 can also be centered from the light receiving surface. The interview body is constructed in such a way that τ Xingren's radial dividing line is divided into δ parts. There is no limitation on the division of 6106. Min 疋 wan, a pyramid with thousands of faces, and a shape with several curved surfaces can also be formed. In this case, the owner is set to correspond to the divided area of the main beam for light detection by the light receiving unit 107 | § i i i. The optical disc device 1 can also be used as a full-earth element on a light-transmitting member with a roughly flat plate shape. The specific holographic pattern is formed by engraving the surname to form a segment 稜鏡 106. In the case of a king-hearted piece for eight, it should be a surface relief type A hologram can also be a blazed hologram to improve diffraction efficiency. Furthermore, as shown in FIG. 16, the optical disc device i uses the light profile 79 divided into four areas instead of the division 稜鏡 1 () 6, and the same effect can be obtained. At this time, in order to obtain the same effect as that of the division 稜鏡 1G6, the light bulb 79 is provided with county regions ^, y '-' h ', y4', and the division directions of the division regions yi, y2 ', y3, and y4 are different. Specifically, the directions of the grooves forming the divided areas ^ and 33 and the directions of the grooves of the divided areas 22 and 74 are orthogonal to each other. The grating 79 diffracts and divides the light returned by the incident disc 2 into four parts according to the groove directions and grating constants of the divided areas yi, y2, y3, and y4, and guides the light receiving section 107 to the main beam. Detector m. The grating 79 is formed as a hologram element by processing a special hologram pattern. In addition, when a holographic element is used, a surface relief type hologram is preferable, and a holographic hologram may also be used to improve the diffraction efficiency. The optical disc device 1 can also be designed to have a reflective surface in the optical path, so that by using the reflective surface, the degree of freedom in optical design can be improved by bending the optical path. -59- 200306548 Furthermore, since the optical disc device 1 is such that the incident angle of the light incident from the optical disc 2 incident on the division 稜鏡 106 is formed at 45 for each side of the division 稜鏡 106. In the following, the inclination angle of each face of the segmentation 稜鏡 106 will also be 45. In the following, in order to prevent the incident returning light from entering the total reflection condition, the refraction angle can be increased, so the beam point interval of each divided returning light can be separated, and each of the light detectors 111 for the main beam can be enlarged. The interval between the divided regions and the interval between the main beam light detection cry 111 and the side beam light detection 11 112, ⑴ can relax the combined precision of the optical pickup device 3. Two or two light: Set 1 in the above-mentioned optical pickup device 3 In order to obtain the focused Tiger FE, the so-called astigmatism method is used, but a Foucault method or the like can also be used as a detection method. The optical disc device uses the so-called Dpp method, but other detection methods such as the differential knife phase detection method are used. The structure of the image is in the above-mentioned optical pickup device 3, and the correction strain ^ may also be located at another position. The position of the component for correcting the astigmatism should be set to be the one that can be distinguished. Moreover, the light rays return to the incident surface or exit surface of the light. ', Clothing set 1 is made of the above-mentioned optical pickup device, ^ ^ amount of components; MU + 3 towel is to shoot astigmatism cylindrical surface, etc., but it is not limited to this, it can also be described in the above example. At the time, the toilet was right, there were optical systems 30 and 60 with correction first movement, optical system 100 with correction astigmatism, and the structure and operation of the optical pickup set 3, but changed and corrected at 0 and 140. Astigmatism optical system. For /, there is a correction optical path-60-200306548 port and 'the following describes the structure of the optical pickup device 3 with an optical pickup device 3 having a correction optical path variation and a compensation system, and the optical system 30 and the optical system 60 are the same as those having an optical system, and are provided in advance. In the structure common to the pickup device 3, $ 圮 A is used to bluff, and the detailed description of the sun and the moon is omitted. ^ Shell "Master 5 has shared

The optical system of the optical pickup device 3 has a sequence of H and. #, S Figures ~ 8, according to light and light. First source 61, which emits a laser element ⑸, which is divided from the light source 61 :, The light returned by the composite light 2 is separated from the emitted light, and the light is reflected back from the disc; the aperture diaphragm 33 ^ knife brake 舁 the light separation element ⑸ shot, ⑸ from light source 61 The numerical aperture NA that is emitted and passes through the composite light 1; the output light that is condensed on the objective lens face 2al t circle 33 is condensed on the recording surface 2a of the optical disc 2, and the light receiving portion 152.1v, which is connected to the optical disc 2 The light that shoots back. The light source 61 is a semiconductor laser having light from the mouth of the light emitting point 61a. The emission wavelength is as shown in FIG. 28 and FIG. 29. The laser beam r U η ^ ^ ^ yu Xianfan 151 is formed into a block shape by emitting a shaped tree moon, and X, ， 有 · 郇 近前 源 61, and shot t 纟 + ψ $ + ^ from the hair light spot 6 1 a of this / soap. 盥 Xi Yi ―; the first surface 153 that is orthogonal to the emitted light axis "" The second face 153 is parallel to the second face 154 opposite to each other; the first face 4 inclined at a certain angle and is inclined only K ...; and perpendicular to the first face 153 and the second face, and to the third face 5 5 Only lc, 1 mile and 1 ounce needle know the angle, and the fourth face is 15 6 °. The self-light source is set on the brother-face 153. The light emitting point is divided into 0 times light and ± 1 attack: ^ Body Ding First out of the first — a first diffraction grating 1 6 1 to discuss the beam 150 to obtain the tracking error signal TE, the so-called DPp method -61-200306548, and by the light receiving unit 152 to receive the first The diffractive grating 161 is divided into ± 1 times of light for tracking servo configuration. The first surface 1 54 is provided with a second diffraction grating 丨 62, which is used to make the light reflected from the optical disk 2 be the first diffraction grating. 161 minutes The 0th-order light and ± 1st-order light diffraction are further divided into 0th-order light and earth-order light, and if the + 1th-order light is used as the reflected light and the light path of the emitted light, the second path is separated. A holographic element 163 is provided on the optical path of the reflected light separated by the second diffraction grating 162, so that the reflected light is reflected and diffracted, and further divided into 0-order light and earth-order light. For example, the "secondary light" is used as the reflected light to correct the optical path variation generated by the second diffraction grating 1 62 to further correct the amount of astigmatism. . The Hai Wang Xi element 1 63 is provided with a specific reflective film on the third surface 1 5 in a manner of total reflection of incident incident light, and functions as a so-called reflective holographic element. The hologram element 163 is formed by etching a specific hologram pattern. When the hologram element 163 is used, it is preferably a surface relief type hologram or a blazed hologram to improve diffraction efficiency. The fourth face 156 is provided with a division chirp 164, which corrects the optical path variation by the hologram element 163, and is located on the optical path of the reflected light, and divides the returned light into 4 parts. As shown in Fig. 30 and Fig. 31, the edge division 稜鏡 1 64 is formed into a roughly regular quadrangular pyramid shape, and is reflected and diffracted by the holographic element 163-the secondary light is at the focal point or near the focal point of the diffracted light. The center of the diffracted light is arranged so as to be incident on the center of the vertex of the regular quadrangular pyramid. The division 稜鏡 1 64 is located inside the composite optical element 151, and is disposed toward the vertex angle on the inside side. That is, the division 稜鏡] 64 is diffracted by the 0th light of the three beams divided by the first diffraction grating -62- 200306548 161 by the second diffraction grating "a, and is reflected and diffracted by the holographic element 163 And 入射 are arranged in such a way that they are incident at the apex angle. In addition, ^ division 稜鏡 164 is arranged with the bottom face of a regular quadrangular pyramid facing the optical axis of the -1st-order light reflected and diffracted by the hologram 163 orthogonally. The reflected light separated by the second diffraction grating 162 passes through, and only a specific amount of the moonlight complex optical element 1 5 1 is given to the reflected light incident on the divided beam 64 1 1 by adjusting the light source 6 1 The position of the emitted light in the direction of the optical axis can easily adjust the defocus of the optical disc 2. The composite optical element 1 5 1 is formed by emitting a molding resin material. Other forming methods can also be performed by etching. The first diffraction grating 161, the second diffraction grating 162, the holographic element 163, and the division 稜鏡 η # may be formed by machining. In addition, the material forming the composite optical element ΐ5ι is not limited to a resin material. , Can also use transparent glass material In addition, the optical structure can also be changed locally by combining these optical materials. At this time, the composite optical element 151, the composite optical element 32, and the composite optical element 62 are described in the same way as in the second calculation. The diffracted light tree 162 and the holographic element ⑹ 之 光 # constant and the angle formed by the third surface 155 and the second surface 154 are used to design the composite optical element 151 ′. The returned light is guided to the vertex angle of the division 稜鏡 164. In addition, the composite optical element 151 is the same as the above-mentioned optical system 100, 12, and 13; The element 1 67 'is corrected in such a manner that the optimal astigmatism amount is formed on the focal servo. The composite optical element 151 thus designed is changed in the wavelength of the emitted light from the light source 61-63- 200306548, and τ Α ί β, a fill W soil $ 'The light returned from the disc 2 changes the optical path of the second diffraction grating 162, and the second light of the separation is reflected and diffracted by: 二; Into -1, ', the reflected light always leads to the division 稜鏡 1 The apex angle of 64, grid: =: = composite ... The second diffractive light lens of 151 is called at least one convex lens, and it will converge the light emitted from the light source 61: and focused by the aperture 33. The light is arranged on the optical disc 2. As shown in FIG. 32, the incense umbrellas are all square shaped main beams that receive the main beams of the main beam of the first diffraction grating 161 with a photodetector. It also breaks the two sides of the first-order light divided by the first diffraction grating 161 and the two sides of the first beam, and the roughly square side beams use photodetectors 72, 73. The light receiving arrangement is corresponding to The position of each of the reflected light is divided by the division 稜鏡 4 of the optical element 151. Light-receiving section} 52 is provided with a centrally-shaped and roughly square photodetector 主 for the main beam, and the main-beam photodetector 171 is sandwiched therebetween and is positioned on one of the two sides of the roughly square group Square beam photodetectors 172, 173. In addition, the main beam photodetector 171 of the% light section 152 has light receiving areas a4, b4, c4, and d4 divided into four equal parts by a set of division lines that are straight to each other. Each light-receiving area h t 4 b4 C4 is irradiated with the respective reflected light divided into four parts by the segmentation 稜鏡 164 in the heart. -64- 200306548 The side of the light receiving unit 1 5 2 is divided by the mt μ & beam photodetectors 172 and 173 into I # secant lines and divided into two halves. First & domain ~, dagger, and light receiving area g4, h4. Gu Youguang In the fields e 4, f 4, A_44 · t, A > ..., $ should be divided by the first diffraction grating 161-a shot of the light returned by the human light from the optical disc 2 corresponds to Became the first diffraction ^ each first & domain g4, within the dagger, +, the first light divided by ± 1 times the light from the light 的 2 the other side of the light returned. The optical pickup device 3 has a transflective mirror drive mechanism that has: a lens holder that holds the objective lens and supports the lens at Shilikou ^, and the brothers can focus parallel to the optical axis of the objective lens 34 Direction and Orthogonal Dimensions 4 ά Straight and shifted in one of the axial directions of the tracking direction of the optical axis of the objective lens M — add /, components, and make the lens support and drive by electromagnetic force Change is located in the second axis Fang Di Shi. The door's fast magnetic drive unit, but it is not shown on the picture = the drive mechanism misfocuses the μ number and the side beam light detector according to the main beam photodetector ΐ7ι detection of the light receiving unit 152! 7 2, i 7 3 detected = vertical error signal, respectively, driving the objective lens 34 in the focusing direction and: the vertical direction 'focuses the output light on the recording surface of the optical disc 2 ~ the recording track'; in addition, the aforementioned composite optical element 151 The division 稜鏡 164 can also be formed as a 0 pyramid. In this case, the photodetector for the main beam of the light-receiving section 152 can be divided into eight parts by a dividing line radiating radially from the center of the light-receiving surface. In addition, the division 稜鏡 1 64 of the composite optical element 151 is arranged on the inner side of the four sides 156, but the fourth side 156 may be provided on the side of the fourth side. The division 稜鏡 164 of the composite optical element 151 is not limited to a pyramid having a flat surface, and may be formed into a shape having a plurality of curved surfaces. In this case, -65-200306548, it is set to correspond to the divided area of the main beam photodetector 171 of the light receiving unit 152. Furthermore, the composite optical element 151 can also be formed by using the first diffraction grating 161 and the second diffraction grating 162 as holographic elements, respectively, and processing a specific holographic pattern. In the case of using a holographic element, a surface relief type hologram should be used, or a blaze hologram can be used to improve diffraction efficiency. The same effect can be obtained by using the composite optical element 1 51 as shown in FIG. 16 by using a grating 79 divided into four regions instead of the division chirp 164. At this time, in order to obtain the same effect as the division 稜鏡 164, the grating 79 is provided with divided regions w, y2, ys, and y4, and the directions of forming grooves in the divided regions yi, h, ys, and h are different. Specifically, a, the direction in which the grooves of the divided areas y i and y 3 are formed and the direction in which the grooves of the divided areas y2 and y4 are formed are orthogonal to each other. The grating 79 diffracts and divides the light returned by the incident disc 2 into four parts in accordance with the groove directions and grating constants of each divided area y! '' Ys' y4 and guides the light detector for the main beam of the light receiving section 152 171. The grating 79 is formed as a hologram element by a hologram pattern specific to the etching process. In addition, when a holographic element is used, a surface relief type hologram is preferable, and a holographic hologram may also be used to improve the diffraction efficiency. Furthermore, the composite optical element 151 can also be designed to have a reflective surface inside, so that by using the reflective surface, the degree of freedom in optical design can be improved by bending the optical path. Furthermore, since the composite optical element 151 makes the incident angle of the light incident from the optical disc 2 incident on the division 稜鏡 164 to 45 for each surface of the division 稜鏡 164. In the following, the inclination angles of the faces dividing the 稜鏡 164 will also be 45. In the following, ~ 66-200306548 to avoid incident incident rays that first violate the total reflection condition. Therefore, it can separate the beam point interval of the light that is reflected by σ + θ plus refraction Φ Α σ.可 _ Large main beam photodetector 171 has been enlarged within ^. 1 The gap between the knife-edge area of the main beam and the main detector for the first detector m and the side beam are detected by light: using a wide optical pickup device 3 Combined precision. 173 can be equipped with the above-mentioned apricot and ^ a a set 1 by self-beam 2: non-learning pickup device 3 optical disc installation 2 light emitted by the first disc 2 'according to the optical pickup error & No. and tracking error, ^ 〇〇 ^^ ^ One of the optical pickup device 3 axis: "1 circuit 1. Output control signals to the central ... two-axis actuation " driven by the objective lens 34 and changed to light 2 In the direction of the required recording, the emitted light passes through the required recording path of the objective lens = 2. The optical disc device was previously demodulated by the signal 2 and the wrong #correction circuit U to demodulate the optical pickup 3 signal and correct the error. = Signal. Duanmu " The surface 14 outputs the reproduced light Si Zhiguang with the return light Γ of the optical pickup device 3 with the above-mentioned optical system 15 °. The meal photo illustrates the emission in the optical pickup device 3. Light and light, free light optical disc device 1 When the information is reproduced from the recording surface 2a of the optical disc 2, the light emitted from the source 61 is transmitted through the composite optical element. The light is divided into three packages including W-order light and ± 1-order light. Beam. The light emitted by 3 beams passes through the second optical element of the composite optical element. The objective lens 34 is focused on the recording surface of the optical disc 2. The light returned from the recording surface 2a of the optical disc 2 is guided by the second optical element diffracted by the second diffracted light thumb 162 to introduce the light directed toward the third side. In the process, +1 times -67. 200306548 The light is incident on the holographic element 1 6 3. The λ 4 is incident on the holographic element 1 63 and the +1 order light from the second diffraction grating 162 is entered from a hunter and reflected by the holographic element 163 And diffraction, the _ 丨 time light is incident on the top angle of the segmentation 稜鏡 1 64. This is only a month, and the second diffracted light in the holographic element 163 + 1 2 + 1 light makes up two μ 1 罘The optical path variation of a diffraction grating 16 2 and correction of the astigmatism amount. A ^ shot at the -1 angle of the top angle of the regular quadrangular pyramid which is cut 1 64 is shot from the peripheral surfaces of the regular quadrangular pyramid respectively. The sub-refractions are respectively refracted in different directions, and the sub-reflection is divided into four reflected light, and the light receiving areas a4, b4, C4, d4 of the main beam photodetector 照射, which are respectively irradiated to the receiver 152. Wang Xin 7L piece 16-3 diffraction diffracted light incident on the vertex angle of the split 稜鏡 ⑹: As shown in the old 3A, the recording center of the objective lens along the disc 2 is located at the position k "At the top corner of the cutting 164, people shot back light that formed a roughly circular shape. In addition, the diffracted light is incident on the ^^ 宝 | # 1. When the top angle of the mouth mirror 164 is as shown in FIG. 33A, when the objective lens 34 and the recording surface h of the optical disc 2 are too close, the objective lens 34 is Deviation from the focal position, as a result of the astigmatism generated by the diffracted light passing through the composite optical element ⑸, in the division 稜鏡 丨 64 ^ ^ ^ ^ ^ ^ ^,.? _ Only the inner axis has a long axis forming the upper right of the figure Square ellipsoidal diffracted light. In addition, when the diffracted light is incident on the vertex angle of the segmentation 稜鏡 164, as shown in FIG. 33C, the lens 34 passes through the center of the lens, and the focal position of the objective lens M p is 'so' because the diffracted light passes through the composite optical element ⑸: 2 like politics. An ellipsoidal diffracted light with a long axis forming the upper left in the figure is incident on the top corner of the knife mirror 164. Therefore, in the state where the objective lens 34 is deviated from the in-focus position, the diffracted light enters -68- 200306548 at the top angle of the division 稜鏡 164, and the division 稜鏡 164 is opposite to each other, and the peripheral surface is x9 'X " With the surrounding surface Xι. On the χ ", it is distinguished that most of the incident diffracted light is incident on the peripheral surfaces of one group, and very little incident light is incident on the peripheral surfaces of the other group. That is, as shown in FIG. 33A, on the split prism 1M where the rounded diffracted light is incident, most of the diffracted light is incident on a set of opposite peripheral surfaces &, X " and a very small part of the diffracted light It is incident on a set of opposite peripheral surfaces A. ~. In addition, as shown in FIG. 33C, the elliptical diffracted light on the human splitter mirror 164, most of the diffracted light is incident on the peripheral surfaces of a group and a very small part of the diffracted light is incident on each of the-groups opposite Perimeter X9, χπ. ―The light returned from the disc 2 among the 0th light divided by the first-diffraction grating 161 is formed by being diffracted by the second-diffraction grating 162], and the · i-th light is incident on the division 稜鏡Each of the peripheral surfaces X9, Xiq, & of 164 is refracted in different directions, so it is divided into four pieces of reflected light, and is incident on each of the main beam photodetectors 171 of the light receiving section M2. Zone ... C4,1. As shown in tf in FIGS. 34A and 34C, the two light receiving areas a4 ′ q and the light receiving areas ^ ^ of the two groups facing each other of the main beam photodetector 17l receive more light receiving amounts, and The area of the other group receives less light. In other words, when the elliptical diffracted light shown in FIG. 34A is incident on the division 稜鏡 164, the main beam photodetector 171 is shown in FIG. 34A, and the amount of light received by each of the light receiving areas a4 and c4 increases. Each of the light-receiving areas, ..., ..., the amount of light is reduced. When the elliptical diffracted light as shown in Fig. 3 is incident on the division 稜鏡 164, the photodetector m for the main beam is shown in Fig. 相对, and the relative amount of light received by the light region b4: d4 varies as shown in Fig. ⑽. More 'and the amount of light received by C4 is smaller than that of each light receiving area. When the circular diffracted light shown in FIG. 33B is incident on the top angle of the division 稜鏡 64, the photodetector m for the main beam is as shown in FIG. 34B. It shows that the relative light is equal to each light-receiving area and the light-receiving amount of the heart. — Therefore, when the main beam photodetector 171 detects SanSc4 and Sd4 when the output of each light-receiving area ^ A is out of focus, " #uFE can be calculated as shown in Equation 25 below. (25) FE = (Sa4 + Sc4)-(Sb4 + Sd4) That is, when the main beam photodetector 171 is positioned on the objective lens "for the recording surface 2 of disc 2 and a is in the focal position, # 由When the focus error L-beam photodetector 171 calculated by Equation 25 is too close to the objective lens M and the recording surface of the disc 2, the focus error message is positive and the objective lens 34 is too far away from the record 2a of the disc 2 At this time, the focus error signal Qiu is negative. The light detector for the main beam of the fork light unit 152 described above is made by incident on each of the beam points ah 〆 4,, C4, and d4 respectively. Output to obtain the focus error signal FE and obtain the reproduced signal. In addition, the photodetectors i72, in of each side beam of a group are received by the light from the optical discs with the light receiving areas e4, f4 'g4' h4. The first-received light quantity of the first-order light divided by the diffraction grating 161. Therefore, each light-receiving area ha of the light detector ^ '⑺ for the side beam is ^ 4'1. 4. When the porphyrin, ~, is called, the tracking error signal TE can be calculated as shown in Formula 26 below. -70- • (26) 200306548 TE = (Sa4 + Sc4) _ (Sb4 + Sd4) -a ((Se4-Sf4) + (Sg4_Sh4)) As mentioned above, the optical disc device 丨 according to the focus error signal redundancy and tracking error signal te obtained by the optical pickup device 3 with the optical system i50, the servo circuit 10 controls The lens driving mechanism drives the objective lens 34 to be located in the focusing direction and the tracking direction, respectively, so that the emitted light is focused on the recording surface 2a of the optical disc 2, and information is reproduced from the optical disc 2. As described above, the optical disc device has optical The optical pickup device 3 of the system 15 has a composite optical element i 5 i, which is provided with a first diffraction grating i 62 which is diffracted by the light returned from the optical disc 2; and is to be subjected to the second diffraction grating 1 62 diffracted +1 times of light is used as the reflected light, and the holographic element diffracting the returned light 1 63 'even if the fluctuation of the oscillation wavelength of the emitted light from the light source 6 1 due to a change in ambient temperature, It can be guided to the appropriate position, and the astigmatism can be appropriately corrected by the hologram element 1 63. Therefore, the optical disc device 1 such as the composite optical element i 5 J can use an optical pickup device with a simple structure without increasing the number of parts. Focus error The reliability of No. FE is improved. In addition, due to the optical disc device! The optical pickup device 3 having the optical system 15 is provided with a composite optical lens that separates the emitted light and the returned light by 151, and compensates for the emitted light emitted from the light source 61. The function of optical path variation due to wavelength variation and the correction of astigmatism 'so that the number of optical components can be kept to the minimum necessary' simplifies the structure of the optical system 15, promotes miniaturization, and reduces manufacturing costs. Optical system 1 5 0-71-200306548 in the optical pickup device 3 of the optical disc device 1 contributes to a reduction in manufacturing cost and incorporates the optical element 151, thereby improving productivity and reliability. The optical disc device 1 has a complex optical pickup unit < especially a pickup device 3 as shown in FIG. 28. Nine to π piece 151, the composite optical element ΐ5ι has a light division 稜鏡 164, which is compared with the form of the main beam and 12 beam back to the split beam point. The division line on the recording path ㈣ == accepts The four main beams of the returned light divided by the division prism 164 == the light detectors "1" of each light receiving area a4, b4, C4, the chirped beam is small, and the main beam is widened with the light detector 171 divided by 4 The high precision of the blade. The "disc set" required for the positioning of the knife edge J position can reduce the cost of the optical pickup device 3 of the measuring device 1 71, and the cost of using the light is high. In the manufacturing steps of the optical pickup device 3, the position of the beam detector 171 is adjusted, and the reliability of the focus error signal FE is obtained. In addition, the optical disc 1 is set to obtain the focus error of the optical pickup device 3 described above. The signal FE adopts the astigmatism method used in private soil and water bamboo and wipes, but other detection methods can also be waited for. The Foucault method is also used: the disc is not easy to form a composite optical element as described above. Units: Falcon optical elements form light m individually in the same configuration as above The same function can be obtained. In addition, relevant industry players understand that the present invention is not limited to the above-mentioned embodiments described with reference to the drawings. Various changes, substitutions, or equivalents can be made without departing from the scope and spirit of the patents described below. -72- 200306548 Feasibility of industrial utilization, the above-mentioned 'The optical pickup device of the present invention is used in an optical disk device, and the first 5 elements of the present invention are used for optical pickup.' This J is very productive, promotes low cost and low reliability, and improves the reliability of the focus error signal. Furthermore, the optical disc device of the present invention is a composite optical pickup device, so it can be used for pre-exposure. Twistability, promotes the reduction of manufacturing cost, and improves the reliability of the Alejo error signal. The optical pickup device used in the present invention is eight micrometers. When returning light, the system knows that the wavelength of the light emitted by the light source is changed and re-adjusted by the wavelength-driven correction mechanism. Gong Youjin & Cheng's optical path deviation can appropriately guide the light to the light receiving mechanism. So can u The reliability of this T k return disc device's focus error signal ring. Other optical devices of the present invention are used to form the optimal astigmatism amount when separating the light path returned from the optical disc from the optical path of the emitted light. Therefore, the shape of the returned light guided by the light-splitting mechanism can be formed to improve the reliability of the focus error signal of the optical disc device. The composite optical element of the present invention is used in the optical disc device. In the optical pickup device, the productivity can be improved, the manufacturing cost can be reduced, and the reliability of the focus error signal can be improved. [Brief Description of the Drawings] FIG. 1 is a side view showing an optical system of a conventional optical pickup device. FIG. 2A Fig. 2C shows the beam points of each light receiving area of the main beam photodetector of the previous optical system, and Fig. 2A shows that the objective lens is close to -73-200306548-ticket spoon-shaped heart. Fig. 2B shows The state where the objective lens is in the focusing position, FIG. 2C is a diagram showing a state where the objective lens is far from the optical disc. Fig. 3 is a diagram showing a state in which the center of the beam spot deviates from the center of the light-receiving surface of the photodetector for the main beam of the previous optical system. Fig. 4 is a schematic diagram showing the structure of an optical disc device according to the present invention. Fig. 5 is a schematic diagram of an optical system of an optical pickup device provided in a disc device. Fig. 6 is a perspective view of a composite optical element provided in an optical system of an optical pickup device. Fig. 7 is a perspective view showing the optical path length of the returned light in the composite optical element of the optical system of the optical pickup device. Fig. 8 is an explanatory diagram of a change in the optical path length of the reflected light in the composite optical element of the optical system of the optical pickup device. Fig. 9 is an explanatory diagram of a main beam photodetector and a side beam photodetector provided in a light receiving section of an optical system of an optical pickup device. FIG. 10A to FIG. 10C show the beam points of each light receiving area measured by the main beam used by the optical pickup device. FIG. 10A shows the state where the objective lens is close to the optical disc, and FIG. 10B shows The state where the objective lens is in focus, FIG. 10C is a diagram showing a state where the objective lens is far from the optical disc. Fig. II is a schematic diagram showing another optical system of an optical pickup device provided in the optical disc device. Fig. 12 is a perspective view of a composite optical element provided in another optical system of the optical pickup device shown in Fig. 11. Fig. 13 is a perspective view illustrating a division frame in a composite optical element of another optical system -74-200306548 of the optical pickup device shown in Fig. 11; Fig. 14 is a division view of a composite optical element provided in the other optical system of the optical pickup device shown in Fig. 11 when viewed from the incident surface side of the reflected light. Fig. 15 is an explanatory diagram of a main beam photodetector and a side beam photodetector provided in the light receiving section of the other optical system of the optical pickup device shown in Fig. U. Fig. 16 is a plan view showing a grating having a function equivalent to that of a division optical element of a composite optical element of another optical system of the optical pickup device shown in Fig. U. FIGS. 17A to 17C show the diffracted light incident on the split prism provided by the composite optical element of the optical pickup device shown in FIG. U. FIG. NA shows the state where the objective lens is close to the optical disc, and FIG. 17B shows the objective lens located at the optical disc. FIG. 17C is a diagram showing a state where the objective lens is far away from the optical disc. FIGS. 18A to 18C show the beam points of the respective light-receiving regions detected by the main beam of the optical pickup device shown in FIG. Π, and FIG. 8A shows the state where the objective lens is close to the optical disc, and FIG. 18B shows Shows the state where the objective lens is in focus. Figure 18 C shows a bear image where the objective lens is away from the disc. Fig. 19 is a schematic diagram showing another optical system of the optical pickup device provided in the optical disc device. Fig. 20 is a perspective view illustrating a division frame provided in another optical system of the optical pickup device shown in Fig. 19; Fig. 21 is a side view illustrating a division frame provided in another optical system of the optical pickup device shown in Fig. 19; Figure 2 2 is an illustration of the main beam photodetector and side beam detector installed in the other optical system of the optical pickup device shown in FIG. 19-2003-06506548. 0 Figure 23A to Figure 23C shows the division of the diffracted light from the composite optical element of the optical pickup device shown in FIG. 19, FIG. 23A shows the state where the objective lens is close to the optical disc, and FIG. 23B shows the objective lens is in focus. Figure 2 3 C shows the state of the objective lens away from the optical disc. FIGS. 24A to 24C show beam points of each light-receiving area detected by the main beam of the optical pickup device shown in FIG. 19 with light detection. FIG. 24A shows a state where the objective lens is close to the optical disc, and FIG. 24B shows an object The lens is in the in-focus position, and FIG. 24C is a diagram showing a state where the objective lens is far from the optical disc. Fig. 25 is a schematic diagram showing another optical system of the optical pickup device provided in the optical disc device. Fig. 26 is a schematic diagram of another optical system of the optical pickup device provided on the optical disc. Fig. 27 is a schematic diagram of another optical system of the optical pickup device provided in the optical disc device. # Fig. 28 shows another optical system of the optical pickup device provided in the device. Fig. 29 is a perspective view of the composite optical element provided in the optical pickup device shown in Fig. 28. Fig. 3-0 shows the optical device provided in Fig. 28. An oblique view of a split beam in 70 pieces of complex optics of other optical systems of the pick-up device.: 3 = Observed on the incident surface side of the reflected light. It is set in the composite optical element of the optical system of the optical clothing shown in FIG. 28. Segmentation Map-76- 200306548

Fig. 32 is an illustration of a main beam photodetector and a side beam detector provided in a text light section of the other optical system of the optical pickup device shown in Fig. 28. Figs. 33A to 33C show incident light. "The split diffracted light possessed by the composite optical element shown in the optical pickup arrangement shown in Fig. 33A shows the state where the objective lens is close to the optical disc, and the figure shows the state where the objective lens is in focus. Fig. 33C shows The object lens is far away from the optical disc. Figs. 34A to 34C show the beam points of each light receiving area of the main beam photodetector of the optical pickup device shown in Fig. 28, and Fig. 3 4A shows the object In the state where the lens is close to the optical disc, FIG. 34B is a diagram showing a state where the objective lens is located at a focusing position, and FIG. 34C is a diagram showing a state where the objective lens is far away from the optical disc.

2,204 FE 61, 101, 211 212a 212b 33, 104, 214 ΝΑ 34, 105, 215 63, 107, 152, 216 Light-receiving integrated element Optical disc focusing error signal light source Three-beam diffraction grating beam splitter Aperture aperture numerical aperture to objective lens light receiving unit -77- 200306548 a5, b5, c5, d5, al, bl, cl, dl, Sal, Sbl, Scl, Sdl, a2, b2, c2, d2, Sa2, Sb2 , Sc2,

Sd2, a3, b3, c3, d3, e3, f3, g3, h3, Sa3, Sb3, Sc3, Sd3, a4, b4, c4, d4, e4, f4, g4, h4 2a, 205

TE 1 3 4 5 6 7 8 9 10 11 12 13 14 30, 60, 100, 120, 130, 140, 201 32, 62, 151 ^ 212 4 8 8 103a, 123a, 133a, 143a, 153 light receiving area I own recording surface tracking error signal disc device optical pickup device disc rotation drive mechanism transmission mechanism control section disc table spindle motor control circuit servo circuit drive controller signal demodulation circuit error correction circuit interface optical system composite optical element first surface -78 -200306548 42, 82, 103b, 123b, 133b, 143 45, 75, 161 46, 76, 162 47, 77 11 51, 9 Bu 111, 171, 221 52, 53, 92, 93, 112, 113, 172 61a , 101a 83, 133c, 143c, 155 84, 133d, 156 133e 64 65 78, 106, 164 79 yl, y2, y3, y4 xl, x2, x3, x4, x5, x6, x7, xx9, xlO , Xl2 102 103, 123, 133, 143 163, 167), 154 second diffraction grating of the first side-diffraction light thumb third diffraction grating light detector for the main beam, 173 light for the side beam Detector Luminous point Three sides, four sides, five sides, first visor, visor, one visor, splitting prism, grating, and reporting area 3. Peripheral diffracted thumb, beam splitter, hologram element -79-

Claims (1)

200306548 Scope of patent application: L An optical pickup device comprising: a light source, which emits light of a specific wavelength, and an objective lens, which is to be emitted from the above-mentioned light source disc and to be returned from the above-mentioned optical disc. The emitted light is condensed in the optical element. It has a diffractive element. The emitted light emitted from the light source is transmitted and transmitted from the light monument described above, and the optical path change correction mechanism is as follows: The position of the incident returning light of the diffracted diffraction is corrected due to the change of the distance from the element = Γ The light of the returning light generated by the diffractive element: moves the returned light to a specific position; and the light and light mechanism, which is based on A number of corrections 2 were made before the field coupler returned to the light after the optical path changes described above. For example, the scope of the application for patents is especially picked up, where the above-mentioned diffractive element and the above-mentioned optical path variation correction mechanism of the above-mentioned composite structure are integrally formed of a resin material. For example, the optical pickup device of the patent application P item, wherein the above-mentioned diffraction element is a holographic element. = The optical pickup device claimed in item 1 of the patent scope, in which the above-mentioned optical path motion correction mechanism is another diffractive element, and further diffracts the return light diffracted by the above-mentioned diffractive element. For example, the optical pickup device of claim 4 in the patent scope, wherein the other diffractive elements are holographic elements. For example, the optical pickup device of the first patent application scope, in which the above-mentioned composite 2003.058548 optical element is further attacked, and / or there is a light division mechanism, which is arranged after the above-mentioned optical path change correction machine ^ is used to correct the optical path change. The position where the incident light is incident on the light 'and the above-mentioned shot-receiving eight-r-blades are guided into a plurality of directions to each light-receiving area of the light-receiving mechanism. Such as applying for a patent. — The optical pickup device of item 6 in which the above-mentioned diffractive element, the above-mentioned optical path variation correction mechanism, and the above-mentioned optical division mechanism of the composite 8 · 9 = piece are integrally formed by a resin material. : The optical pickup device under the scope of patent application No. 6 in which the above-mentioned optical sub-mechanism is a unit composed of several planes or curved surfaces. The optical pick-up device of item No. 8 of the patent patent, wherein the above-mentioned beam of the above-mentioned composite light is formed into a substantially quadrangular pyramid shape, and the original is corrected after being corrected by the above-mentioned optical path variation correction mechanism. The light is divided into 4 parts, and the light receiving area that the light receiving mechanism receives each of the reflected light passing through the above-mentioned 稜鏡 1 ° of the composite optical element into 4 parts is divided into 4 parts. The optical pickup device according to item 8, wherein the incident angle of the reflected light to each surface after the ray formation is corrected by the optical path variation correction mechanism is 45. the following. u · For example, please ask for the optical pickup arrangement of item i of the patent scope, wherein the above-mentioned composite optical element further has a reflection mechanism 'which is on the optical path of the light emitted from the light source, so that the emitted light is reflected on the diffraction element And / or on the optical path of the returned light after being diffracted by the above-mentioned diffractive element, so that the 4 returned light is reflected at the above-mentioned specific position. 200306548 12. The optical pickup device according to item 11 of the scope of patent application, wherein the diffractive element, the optical path variation correction mechanism, and the reflection mechanism of the composite optical element are integrally formed of a resin material. 13. The optical pickup device according to item 1 of the patent application range, wherein the composite optical element further has another diffractive element, which is arranged on the optical path between the light source and the diffractive element, and will be from the light source. The emitted light is divided into three parts: 0th-order light and 1st-order light. The light-receiving mechanism receives the 0th-order light divided by the above-mentioned additional diffraction element among the returning light divided by the light-dividing mechanism. A focus error signal is obtained, and a tracking error signal is obtained by receiving the light i times divided by the above-mentioned additional diffractive element. 14.2 The optical pickup device according to item 13 of the patent scope, wherein the above-mentioned diffraction element of the above-mentioned composite element, the above-mentioned optical path variation correction mechanism, and another diffraction element are formed by a resin material body. 15 · == The optical pickup device according to the thirteenth item, wherein the above-mentioned additional 7L element is a holographic element. 16 · If the scope of the patent application for the correction mechanism: device, in which the astigmatism generated by the above-mentioned optical path is from the optical path of the light beam emitted by the above-mentioned light source And the above-mentioned diffractive element, a self-beam. In the prior right of emission, the optical beam pick-up device 200306548, which covers the effective beam beyond the effective light beam, is provided with a light-shielding mechanism, which is directed to a certain position by the optical path change correction mechanism. In the optical path of light, light beams other than the effective light beam are blocked. 19. An optical pickup device, comprising: a light source that emits light of a specific wavelength; a beam splitter that separates the optical paths of the emitted light from the light source and the reflected light reflected by the optical disc; and The astigmatism is corrected in the optical path of the above-mentioned returning light; for the objective lens, the light emitted from the light source is condensed on the optical disc, and the light returned from the optical disc is condensed; , Which is arranged at a position where the return light separated by the beam splitter is incident, and divides the return light into several; and a light receiving mechanism, which receives the plurality of light divided regions divided by the light dividing mechanism Echoing back light; The above-mentioned light division mechanism is made up of several planes or curved surfaces. 20. The optical pickup device according to item 19 of the patent application scope, wherein the prism is formed into a substantially quadrangular pyramid shape, and the returned light after the optical path variation correction mechanism corrects the optical path variation is divided into four parts. 21. The optical pickup device according to item 20 of the patent application, wherein the angle of incidence of the reflected light separated by the optical path separation element on each surface is 45. the following. 22. The optical pickup device according to item 19 of the application for a patent, further comprising a reflection mechanism, which is based on the optical path of the emitted light from the light source, and reflects the emitted light on the optical path separation element, and / Or, on the optical path of the returning light separated by the optical path separating element, the returning 200306548 light is reflected at the specific position. 23. For example, the optical pickup device of the scope of application for patent No. 20, in which +-is provided with another diffractive element, which is arranged on the optical path between the light source and the upper and lower element, and emits the light emitted from the light source. The light is divided into three parts: 0th order light and 1st order light. 24. As for the optical pickup device of the 19th scope of the patent application, the above-mentioned eight beams of ## 4 are formed into a generally flat plate shape including a first surface and a second surface, and the first surface reflects the light emitted from the light source, The returned light beam is transmitted through the first surface and the second surface at the same time. A: The optical pickup device of claim 19, wherein the beam splitter is formed into a substantially flat plate shape including a first surface and a second surface, and the light emitted from the light source is reflected by the first surface, and The reflected light is incident from the first surface, reflected by the second surface, and then transmitted through the first surface. 26. The optical pickup device according to item 19 of the patent, wherein the beam splitter includes at least a first surface, a second surface, and a third surface, and these surfaces are arranged in a roughly isosceles triangle shape. The first surface reflects the emitted light ′ from the light source, and makes the returned light incident from the first surface, reflects on the second surface, and transmits the third surface. 27. The optical pickup device according to item 19 of the patent application scope, further including a light-shielding mechanism, which is interposed between the light source and the beam splitter and emits light from the light source > & > ^, 耵In the prior right of light output, light beams other than the effective light beam are blocked. 2δ. The optical pickup device according to item 19 of the scope of patent application, which further includes a light-shielding mechanism 'which blocks the light beams other than the effective light beam during the process of the reflected light separated by the beam splitter 200306548. 29. An optical disc device comprising: an optical pick-up device for: and / or a regenerator aK 'and a disc drive drive mechanism' which rotates the above-mentioned optical disc; and is characterized by: It has: a light source, which emits a specific wavelength to the objective lens, 'which emits the light emitted from the above light source onto the optical disc, and emits the light from the above optical disc.' M < Nine to focus; a composite optical element, which has : Diffraction element, hair, ... The light emitted by the light source is still transparent, and the price is calculated ...., The above • The transmission is transmitted first, the light material returned from the above-mentioned optical disc, and the optical path change correction mechanism. According to the above diffractive element: the position of the ray, correct the return light to the specific position by correcting the return light% k of the diffractive element caused by the wavelength variation of the light emitted from the light source; The burden mechanism is to receive the reflected light after the optical path change is corrected by the above-mentioned optical path change correction mechanism in several party light areas. SO · For example, the optical disc arrangement of item 29 in the scope of the patent application, wherein the above-mentioned composite optics, the above-mentioned diffractive element, and the above-mentioned optical path variation correction mechanism are integrally formed by a tree such as a material. 31. If Su Tuchu is applying for a patent, the 29-item optical disc device will be used, where the above-mentioned diffraction element is a holographic element. The optical disc device according to item 29 of the patent application scope, wherein the above-mentioned optical path is changed, and / or other shots are made, and the return light diffracted by the above-mentioned diffractive element is further diffracted. 200306548 33. The optical disc device according to item 32 of the application, wherein the other diffractive elements are holographic elements. 34_ The optical disc device according to item 29 of the patent application range, wherein the composite optical element further has a light division mechanism, which is arranged at a position where the incident light returns after the optical path variation correction mechanism corrects the optical path variation, and The reflected light is divided into a plurality of pieces and guided to each receiving area of the light receiving mechanism. 35. For the optical disc device according to item 34 of the scope of patent application, wherein the above-mentioned diffractive element, the above-mentioned optical path variation correction mechanism, and the above-mentioned optical division mechanism of the two pieces of composite optics are integrally formed by a resin material. 36. For example, in the case of the patent application No. 34, the above-mentioned light division mechanism is a structure composed of several planes or curved surfaces. 37. The optical disc device according to item 36 of the patent application scope, wherein the above composite optical element: 4 稜鏡 forms a roughly quadrangular pyramid shape, and divides the returned light after the optical path variation correction mechanism corrects the optical path variation into There are four parts, and the light-receiving area that the light-receiving mechanism receives each of the reflected light divided into four parts by the 稜鏡 is divided into four parts. 38. For example, in the 36th edition of the patent application scope, the above-mentioned formation of the incident light after the optical path change correction and correction of the optical structure to correct the optical path change of the incident angle on each side is 45. the following. 39. For example, the first 29 items of the patent application scope, wherein the above-mentioned composite optical element further has a reflection mechanism, and then it is based on the optical path of the light emitted from the above-mentioned light source, so that the above-mentioned shots and shots are reflected first. On the above-mentioned diffractive element, and / or on the optical path of the returned light after being irradiated by the above-mentioned diffractive element, the 200306548 reflected light is reflected at the specific position. 40. For example, the 39th nine-disc dress of the patent application scope, in which the above-mentioned diffraction opening of the composite optical element is especially suitable, the above-mentioned optical path variation correction mechanism, and the above-mentioned reflection mechanism are integrally formed by a resin material. . 31 41. For example, the 29th item of the patent application, where the above-mentioned composite optical element: step has another diffractive element, which is arranged in the water between the light source and the above-mentioned diffractive element. The light emitted from the light source is divided into three parts: 0th order light and ± 1st order light. The light receiving mechanism is connected to ΦL,,, and 2 and each of the reflected light divided by the cutting mechanism is used as the above. 2. Obtain the focus error signal by not firing the 0th order light of the element, and connect ΦI to the ± 1st order light divided by the above-mentioned additional diffraction element to obtain the tracking error signal. 42. If the patent application scope of the first one is 1 device, the above-mentioned diffractive opening, μ, +, and p-upper flight advance correction mechanism of the above-mentioned composite optical element and the above-mentioned additional diffractive element system Integrated molding with resin material. 43. For example, the nineteen-disc split of the patent scope of claim 41, wherein the additional diffraction element is a holographic element. The optical disc device, in which the above-mentioned optical path variation light source emits and produces in the optical path of the light beam 44. If the patent application scope item 29, the correction mechanism is to correct the astigmatism generated from the above. 45. For example, the optical disc device of the scope of application for patent No. 29, which further includes a light-shielding mechanism, which is between the above-mentioned light source and the above-mentioned diffractive Tt member, and is effectively shielded in the optical path of the emitted light from the above-mentioned light source. Beams other than beams. 46. For example, the optical disc device of the scope of application for the patent No. 29, further includes a 200306548 light mechanism, which is used to block the effective beam beyond the effective light beam by the optical path of the returned light directed to a specific position by the above-mentioned optical path variation correction mechanism. beam. 47 ·-An optical disc device 'comprising: an optical table pickup device for recording and / or reproducing information on the optical disc; and an optical disc rotation drive mechanism for rotationally driving the optical disc; characterized in that the optical pickup device is provided with: ·· Light source, which emits light of a specific wavelength; ，, beamsplitter ', which separates the optical path of the emitted light from the light source and the reflected light reflected by the optical disc, and the optical path of the returned light The astigmatism amount is corrected in the middle; the objective lens 'concentrates the light emitted from the light source above and collects the light on it and condenses the light returned from the optical disc; the optical division mechanism' its system It is arranged at the position where the returning light separated by the beam splitter enters, and divides the returning light into several; and the mechanism is in a plurality of light-receiving regions to receive a plurality of returning beams that are divided by the light splitting mechanism. Light; 48 segmentation mechanism is a combination of several planes or curved surfaces. The second "disc installation of item 47 of the profit range, in which the above-mentioned formation :: a quadrangular pyramid shape" divides the returned light after the optical path change correction mechanism corrects the optical path change into four parts. 49. If you apply The light of the 48th item of the patent scope ^ ν, 疋 疋, in which the incident angle of the reflected light of the above-mentioned 稜鏡 formation, house presentation / knife separation element to each surface is 45 ° or less. 50. Such as the scope of patent application The optical disc arrangement of item 47 further includes an anti-200306548 radiation mechanism, which is based on the light emitted from the light source and reflected by the above-mentioned optical path separation element, and the first path is separated by the path separation element and the light is returned. And / or the above-mentioned light is reflected on the above-mentioned specific position. The above-mentioned reflected light is reflected back. For example, the optical disc of the 48th scope of the patent application, the external diffractive element is arranged on the top; On the other optical path, three parts of the secondary light and the primary light from the above-mentioned optical path separation element are divided into three parts. The emitted light is divided into the optical disk device of item 47 in the 0 range, where the above The bundler is formed on one side and the second side Thousand-plate shape, Asia reflects the emission from the above-mentioned light source with the first surface, and ^ 先 First, Asia makes the reflected light pass through the above-mentioned first and second surfaces at the same time. The optical disk device, wherein the beam splitter is formed into a substantially flat plate shape including a first surface and a second surface, and the first surface reflects the light emitted from the light source, and makes the returned light incident from the first surface. Reflected by the second surface and then transmitted through the first surface. 5 4 · The optical disk device according to item 47 of the patent application scope, wherein the beam splitter includes at least the first surface, the second surface, and the third surface, and These planes are arranged in a roughly isosceles dihedral shape. The first plane reflects the light emitted from the light source, and the returned light is incident from the first plane, reflected by the second plane, and transmitted through the plane. The third side. 55. The optical disc device according to item 47 of the scope of patent application, which further includes a light shielding mechanism, which is interposed between the light source and the beam splitter, and is effectively shielded in the optical path of the light emitted from the light source. Beyond the beam -10- 200306548 56. 57. 58. 59. 60. 61. 62. 63. For example, the optical disc device of the 47th scope of the patent application, which further includes a light shielding mechanism, which is separated by the above beam splitter. The optical path of the returned light shields light beams other than the effective light beam. An optical device including: a diffractive element that transmits the light emitted from the light source at a predetermined wavelength and transmits the light returned from the optical disc. Diffraction •, and A optical path variation correction mechanism, which is arranged at the position where the return light diffracted by the above-mentioned diffractive element enters, and corrects the above-mentioned diffractive element caused by the change in the wavelength of the light emitted from the above-mentioned light source. The path of the returned light is actuated 'to direct the returned light to a specific position. For example, the optical device of item 57 of the patent application, wherein the above-mentioned diffractive element is a holographic element. For example, the optical device according to item 57 of the patent application, wherein the above-mentioned optical path variation correction mechanism is another diffraction element, and further diffracts the return light diffracted by the above-mentioned diffraction element. For example, the optical device according to item 59 of the application, wherein the other diffractive elements are holographic elements. Such as Jiaqing Patent Scope Item No. 57, — ,,, Heart — Shao Dan 啕 i / knife cutting mechanism ', which is configured to be corrected by the above-mentioned optical path change correction mechanism; The above-mentioned reflected light is divided into several and guided to a light receiving mechanism having a plurality of light receiving regions. For example, the optical dream ^ Μ Μ of the scope of the patent application (Eu Yuyi's, where the above-mentioned light division structure is hunted by several planes or curved surfaces. Such as the optical device of the scope of patent application 62 'Among them, the above-mentioned 200 is formed into a roughly quadrangular pyramid shape of 200306548, and the returned light after the optical path motion 尨 々 α and the motion correction mechanism corrects the change of the optical path is divided into 4 parts. 64. 65. 66. 67. 68. 69 70. For example, # wind strong seal r in the scope of the application for patent # 62. Learn the device first, where the incident angle of each surface formed by the above-mentioned optical path change correction mechanism is adjusted to 45 ° or less. Optical pair :: Γ: _57 optical device, wherein "quote" is related to the optical path of the light emitted from the light source, so that the light emitted by the light is reflected by the above-mentioned diffractive element Du Η α α and / Or at a specific position on the optical path of the returning light after being diffracted by the above-mentioned diffractive element. The upper returning light is reflected by the above-mentioned optical lens mi as described in the 57th scope of the patent application, which further has another k-ray. το pieces, which are arranged above, k On the right of light between the source and the above-mentioned diffractive element, Ya divides the light emitted from the above light +1. You Yuan divides the light into 0 parts of light and ± 1 order of light. Optical Zhuang-.. ^, clothing, where the above-mentioned additional diffractive element is a holographic element. For example, the light q T u of the patent application No. 57 is especially suitable for clothing, where the above-mentioned optical path change correction mechanism is a correction from the above. In the optical path of the beam emitted from the source above, I 1 gravel is scattered. For example, the scope of patent application No. S7. Λ m ^ Bei Zhi Jiu Yu Yi, which further includes shielding, high wish, and between the above diffractive elements. The light emitted from the above light source # #> 忠 # + hold the light beams other than the effective light beam first. For example, the optical device of the "Patent No. 57", wherein the light-shielding mechanism is further provided by the above-mentioned light. Guidance of the process change correction mechanism 0 -12- 200306548 The light path of the returned light is shielded from the light beam other than the effective beam. 71 · —An optical device 'is characterized by borrowing ·· Beam splitting, which is separated from the light source The emitted light of a specific wavelength and The optical path of the reflected light reflected by the optical disc, and the astigmatism amount is corrected in the optical path of the returned light; and a light division mechanism, which is arranged at a position where the returned light separated by the beam splitter is incident, and The returned light is divided into a plurality of light-receiving mechanisms which are guided to have a plurality of light-receiving areas. 72. 73. | m " Eighth ~ T is another example of the scope and strength of the 71st scope of the patent application., Τ & You especially set one of the above-mentioned 稜鏡 shape; roughly quadrangular pyramidal shape, will pass the above The double-action correction mechanism of Xunren corrects the reflected light after the movement of the optical path is divided into 4 parts. For example, for the first optical scope of the 71st patent application scope, I will give clothing, where the above-mentioned 稜鏡, Θ,! After the optical path separation element is separated, the incident angle of TW Nine to each side is 45 74. If the optical device of the 71st patent application scope, its radiation mechanism is based on the light emitted from the light source; There are: The emission divergence is on the optical path of the returning light after the optical path separation & 'separating the path separating elements, ^ = at the specific position through the light. The above-mentioned retro-reflective light reflection 75. For example, the optically-packed external diffractive το member of item 62 of the scope of the patent application, which is arranged on the above-mentioned light source: Y has an optical path between the other, and will separate the optical path from the optical 4 Secondary light and ± 1 primary light. '、、 之' s outgoing light is divided into 0-13- 200306548 76. The optical device of item 7i of the May patent application, wherein the beam splitter is formed into a substantially flat plate shape including a first surface and a second surface, and The first surface reflects the emitted light emitted from the light source, and the reflected light is transmitted through the first surface and the second surface at the same time. 77. An optical device such as the item 71 in the scope of Shen Qing's patent, wherein the beam splitter is formed into a substantially flat plate shape including a first surface and a second surface, and reflected from the light source with the first surface. The light is emitted, and the returned light is incident from the first surface, reflected by the second surface, and transmitted through the first surface. 78. The optical device according to item 7 of the patent application scope, wherein the beam splitter mentioned above includes a first surface, a second surface, and a third surface, and these surfaces are formed into a general isosceles triangle shape. The reflected light emitted from the light source is reflected by the first surface, and the returned light is incident from the first surface. The second surface is reflected and transmitted through the third surface. The optical device described in p. 71 of the patent scope further includes a light shielding mechanism, which is located between the light source and the beam splitter, and blocks light beams other than the effective light beam in the optical path of the emitted light from the light source. 80. For example, the optical device of the 71st scope of the patent application, which further includes a light blocking mechanism, which is in the optical path of the returned light separated by the above beam splitter / blocks light beams other than the effective light beam. -81 · —a composite optical element having a diffractive element that transmits light of a specific wavelength emitted from a light source and diffracts light returned from an optical disc; and an optical path variation correction mechanism, which It is arranged at the position where the return light emitted by the above-mentioned diffractive element is incident. It corrects the optical path and change of the return light generated by the above-mentioned diffractive element due to the wavelength variation of the emission from the above-mentioned light source. 'And direct the returned light to a specific location. 82. 83. 84. 85. 86. 87. 88. 89. For example, the composite optical element of the scope of application of the patent No. 81, wherein the above-mentioned diffraction = * pieces and the above-mentioned optical path variation correction mechanism are integrated with a resin material such as The composite optical element according to the scope of the patent application No. 81, wherein the diffractive element is a holographic element. : The composite optical element of the scope of application for item 8i, wherein the above-mentioned optical path variation correction mechanism is another diffractive element, and further diffracts the return light diffracted by the above-mentioned diffractive element. = The composite optical element under the scope of patent application No. 84, wherein the other diffractive elements mentioned above are holographic elements. For example, the composite optical element with the scope of patent application No. 72, which further has a light division mechanism, which is arranged at the position where the reflected light is incident after the optical path change correction mechanism corrects the optical path change, and divides the above-mentioned reflected back light into A plurality of sub-units are guided to a light-receiving mechanism having a plurality of light-receiving regions. For example, a composite optical element having the scope of application for patent No. 86, wherein the diffractive element, the optical path variation correction mechanism, and the optical division mechanism are integrally formed from a resin material. For example, the composite optical element with the scope of application for patent No. 86, in which the above-mentioned light splitting mechanism is composed of a plurality of planes or curved surfaces. For example, for the composite optical element in the 88th area of the patent application, the above-mentioned 稜鏡 is formed into a substantially quadrangular pyramid shape, and the returned light after the optical path variation correction mechanism corrects the optical path variation is divided into four parts. -15- 200306548 90. If the compound optical element of the 88th scope of the application for a patent ^ L 4, T where the above 稜鏡 = the above-mentioned optical path change correction mechanism compensates the incident angle of the reflected light after the optical path change is 45 . the following. 91 • If the composite optical element of the scope of application for the patent No. 81, there is a + + and a reflection mechanism, which is based on the light emitted from the above light source = the emission = the reflected light is reflected on the above diffractive element, and / or The light path of the returning light after being shot by Shang Lai makes the above-mentioned returning light reflect at the above-mentioned 4 inch position. ; = = The composite optical element according to item 91 of the patent, wherein the above-mentioned diffractive resin material is integrally formed. The upper and lower reflection mechanism is a composite optical element with %% of the patent scope item 81, which has another diffractive element, which is arranged on the upper eighth of the Zhan Zhili I nine source and the above-mentioned diffraction element = =, And the light emitted from the light source is divided into. -People nine and three parts of ± 1 time light. 94. For example, the composite optical element element of the item% of the scope of patent application, the above-mentioned optical path variation correction mechanism,: wide-radiation is formed by a resin material body. One additional diffractive element is 95. The composite optical diffractive element such as the 93rd in the scope of patent application is a holographic element. / 、 In the above-mentioned other 96 .: The composite optical element with the scope of patent application No. 81, the above-mentioned change correction mechanism corrects the astigmatism generated from jade. In the path of the beam emitted by the H source -16-