Optical pickup, optical drive, and data processing apparatus

Abstract

The invention provides an optical pickup which is applied to the field of optical storage. The optical pickup includes a first laser, a first collimating lens, an intermediate lens group, a first detector, and a focusing lens. The first laser is used for generating a first light beam and transmitting the first light beam to the first collimating lens. The first collimating lens is used for transmitting a first light beam to the focusing lens through the middle lens group. The focusing lens is a binary optical device. The focus lens transmits a first light beam to an optical recording medium, and receives a reflected light beam of the first light beam from the optical recording medium. The focusing lens is further configured to transmit a reflected beam of the first beam to the first detector through the intermediate lens group. The first detector is used for converting a reflected light beam of the first light beam into a first electric signal. In the technical scheme provided by the invention, the binary optical device is used as the focusing lens, so that the rise of the focusing lens can be reduced, and the size of the optical pickup is reduced.

Description

Technical Field

[0001] The present application relates to the field of optical storage, and in particular to an optical pickup, an optical drive and a data processing device. Background Art

[0002] An optical pickup is an optical pickup device placed opposite to an optical recording medium to read and / or write information from the optical recording medium. The optical recording medium may be an optical disc. An optical disc is also called an optical disc, an optical disc or an optical disc. The optical pickup includes a light source, a photodetector and a lens system. The light source is used to generate a light beam. The lens system is used to converge the light beam onto the surface of the optical recording medium and transmit the light beam returned from the optical recording medium to the photodetector. The photodetector is used to convert the returned light beam into an electrical signal. Among them, the lens system includes a plurality of optical elements. The lens system is also used to realize the functions of collimating, redirecting, eliminating or reducing optical aberrations of the light beam. Optical aberrations include spherical aberration and / or chromatic aberration. The size of the lens system is closely related to the size of the optical pickup. Therefore, how to reduce the size of the lens system is a technical problem that needs to be solved urgently. Summary of the invention

[0003] The present application provides an optical pickup, an optical drive and a data processing device. By using a binary optical device as a focusing lens, the sag height of the focusing lens can be reduced, thereby reducing the size of the optical pickup.

[0004] The present application provides an optical pickup. The optical pickup includes a first laser, a first collimating lens, an intermediate lens group, a first detector and a focusing lens. The first laser is used to generate a first light beam and transmit the first light beam to the first collimating lens. The first collimating lens is used to transmit the first light beam to the focusing lens through the intermediate lens group. The focusing lens is a binary optical device. Among them, an optical element with a binary optical structure is called a binary optical device. In the present application, the front surface of the focusing lens is a binary optical structure. The focusing lens is used to transmit the first light beam to an optical recording medium and receive a reflected light beam of the first light beam from the optical recording medium. The focusing lens is also used to transmit the reflected light beam of the first light beam to the first detector through the intermediate lens group. The first detector is used to convert the reflected light beam of the first light beam into a first electrical signal.

[0005] In an optional manner of the first aspect, the front surface of the first collimating lens is a binary optical structure. By using a binary optical device as the collimating lens, the sag of the first collimating lens can be reduced, thereby further reducing the size of the optical pickup.

[0006] In an optional manner of the first aspect, the rear surface of the first collimating lens includes a grating. In practical applications, the influence of chromatic aberration can be reduced by a collimating lens composed of two lenses. The materials of the two lenses are different. In the present application, the first collimating lens processed from one material can reduce the influence of chromatic aberration through a grating and a binary optical structure. In addition, the first collimating lens processed from one material can reduce the influence of ambient temperature, thereby improving the reliability of the optical pickup.

[0007] In an optional manner of the first aspect, the phase order of the focusing lens is greater than the phase order of the first collimating lens. The phase order of the binary optical device is positively correlated with the processing cost and diffraction efficiency of the binary optical device. In the transmission path of the first light beam, the first light beam passes through the first collimating lens once and the focusing lens twice. Therefore, when the phase order of the focusing lens is greater than the phase order of the first collimating lens, the balance relationship between the processing cost and the diffraction efficiency can be controlled.

[0008] In an optional manner of the first aspect, a phase order of the focusing lens is greater than or equal to 16. A phase order of the first collimating lens is less than or equal to 8.

[0009] In an optional manner of the first aspect, the phase period of the isophase surface of the focusing lens is smaller than the phase period of the isophase surface of the first collimating lens. The phase period of the isophase surface of the binary optical device is negatively correlated with the processing cost of the binary optical device. The phase period of the isophase surface of the binary optical device is negatively correlated with the diffraction efficiency of the binary optical device. Therefore, when the phase period of the isophase surface of the focusing lens is smaller than the phase period of the isophase surface of the first collimating lens, the balance relationship between the processing cost and the diffraction efficiency can be controlled.

[0010] In an optional manner of the first aspect, the phase period of the isophase surface of the focusing lens is 2πλ. The phase period of the isophase surface of the first collimating lens is greater than or equal to 4πλ. λ is the wavelength of the first light beam or a common multiple of the wavelength.

[0011] In an optional manner of the first aspect, the optical pickup further comprises a second laser and a second collimating lens. The second laser is used to generate a second light beam and transmit the second light beam to the second collimating lens. The second collimating lens is used to transmit the second light beam to the focusing lens through the intermediate lens group. The focusing lens is used to transmit the second light beam to the optical recording medium.

[0012] In an optional manner of the first aspect, the front surface of the second collimating lens is a binary optical structure. By using a binary optical device as the collimating lens, the sag of the second collimating lens can be reduced, thereby further reducing the size of the optical pickup.

[0013] In an optional manner of the first aspect, the first light beam is blue light. The second light beam is red light. The phase order of the first collimating lens is greater than the phase order of the second collimating lens. The red light is focused and tracked on the swing layer of the optical recording medium. The blue light is focused on the data layer of the optical recording medium. The blue light tracks and follows the red light. Therefore, in the optical pickup, the diffraction efficiency of the red light is required to be lower, and the diffraction efficiency of the blue light is required to be higher. The phase order of the binary optical device is positively correlated with the cost and diffraction efficiency of the binary optical device. Therefore, when the phase order of the first collimating lens is greater than the phase order of the second collimating lens, the balance between the processing cost and the diffraction efficiency can be controlled.

[0014] In an optional manner of the first aspect, the first light beam is blue light and the second light beam is red light. The front surface of the second collimating lens is not a binary optical structure. Generally, the cost of binary optical devices is higher than that of non-binary optical devices. In an optical pickup, the diffraction efficiency of red light is required to be lower, and the diffraction efficiency of blue light is required to be higher. Therefore, when the front surface of the second collimating lens is a binary optical structure and the front surface of the second collimating lens is not a binary optical structure, the balance between processing cost and diffraction efficiency can be controlled.

[0015] In an optional manner of the first aspect, the sagittal height of the focusing lens is less than or equal to 1 mm.

[0016] The second aspect of the present application provides an optical drive. The optical drive includes a spindle motor, a drive motor, and the optical pickup described in the first aspect or any optional manner of the first aspect. The spindle motor is used to carry and rotate the optical recording medium. The drive motor is used to drive the optical pickup to move along the radial direction of the optical recording medium to read data stored on the optical recording medium and / or store data on the optical recording medium.

[0017] The third aspect of the present application provides a data processing device. The data processing device includes a processor and the optical drive described in the second aspect. The processor is used to transmit data to the optical drive or receive data from the optical drive. The optical drive is used to read data stored on an optical recording medium and / or store data on the optical recording medium. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A first structural schematic diagram of an optical pickup provided in an embodiment of the present application;

[0019] Figure 2 A schematic diagram of the structure of the focusing lens provided in the embodiment of the present application during the design process;

[0020] Figure 3 A schematic diagram of the structure of the focusing lens during the processing provided in an embodiment of the present application;

[0021] Figure 4 A schematic diagram of the structure of a first collimating lens provided in an embodiment of the present application;

[0022] Figure 5 A schematic diagram of the structure of the collimating lens provided in an embodiment of the present application during the design process;

[0023] Figure 6 A schematic diagram of the structure of the collimating lens provided in an embodiment of the present application during the processing;

[0024] Figure 7 A second structural schematic diagram of an optical pickup provided in an embodiment of the present application;

[0025] Figure 8 A third structural schematic diagram of the optical pickup provided in an embodiment of the present application;

[0026] Fig. 9 A fourth structural schematic diagram of an optical pickup provided in an embodiment of the present application;

[0027] Fig.10 A schematic diagram of the structure of the optical drive provided in an embodiment of the present application;

[0028] Fig.11 A schematic diagram of the structure of a data processing device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0029] The present application provides an optical pickup (OPU), an optical drive, and a data processing device. By using a binary optical device as a focusing lens, the vector height of the focusing lens can be reduced, thereby reducing the size of the optical pickup. It should be understood that the "first", "second", etc. used in the present application are only used for the purpose of distinguishing the description, and cannot be understood as indicating or implying relative importance, nor can they be understood as indicating or implying an order. In addition, for the sake of simplicity and clarity, reference numbers and / or letters are repeated in multiple figures of the present application. Repetition does not indicate a strict limiting relationship between various embodiments and / or configurations.

[0030] The optical pickup provided by the present application is applied to the field of optical storage. The optical pickup includes a light source, a photodetector and a lens system. The lens system includes a plurality of optical elements. The lens system can be used to realize the functions of collimating, redirecting, eliminating or reducing optical aberrations of a light beam. The size of the lens system is closely related to the size of the optical pickup. Therefore, how to reduce the size of the lens system is a technical problem that needs to be solved urgently.

[0031] To this end, the present application provides an optical pickup. Figure 1 This is a first structural diagram of an optical pickup provided in an embodiment of the present application. Figure 1As shown, the optical pickup 100 includes a focusing lens 101, an intermediate lens group 102, a first collimating lens 103, a first laser 104 and a first detector 105. The first laser 104 is used to generate a first light beam and transmit the first light beam to the first collimating lens 103. The first collimating lens 103 is used to collimate the first light beam so that the first light beam becomes parallel light. The first collimating lens 103 is used to transmit the first light beam to the focusing lens 101 through the intermediate lens group 102. The intermediate lens group 102 includes one or more optical elements. The intermediate lens group 102 can be used to achieve functions such as redirection, power splitting or wavelength splitting of the first light beam. The focusing lens 101 is a binary optical device. Among them, an optical element with a binary optical structure is called a binary optical device. In the embodiment of the present application, the front surface of the focusing lens 101 is a binary optical structure. In the embodiment of the present application, the front surface of the focusing lens 101 refers to the surface of the focusing lens 101 receiving the first light beam from the intermediate lens group 102. The rear surface of the focusing lens 101 refers to the surface from which the focusing lens 101 outputs the first light beam. The focusing lens 101 is used to eliminate spherical aberration in optical aberration, transmit the first light beam to the optical recording medium 106, and receive the reflected light beam of the first light beam from the optical recording medium 106. The optical recording medium is an optical disc. The optical disc is also called an optical disc, an optical disc or an optical disc. The focusing lens 101 is also used to transmit the reflected light beam of the first light beam to the first detector 105 through the intermediate lens group 102. The first detector 105 is used to convert the reflected light beam of the first light beam into a first electrical signal. When the first light beam tracks the data layer of the optical recording medium 106, the first electrical signal is the data stored in the optical recording medium 106. When the first light beam tracks the swing layer of the optical recording medium 106, the first electrical signal can be used to determine the position of the first light beam irradiated into the optical recording medium 106 and the deviation of the swing layer track. By opening the tracking closed loop, the optical pickup 100 can correct the position of the first light beam irradiated into the optical recording medium 106 by the deviation.

[0032] Figure 2 This is a schematic diagram of the structure of the focusing lens provided in the embodiment of the present application during the design process. Figure 2 As shown, in the first step, the structure of the focusing lens 201 is designed. The front surface of the focusing lens 201 includes a certain curvature, forming an aspheric surface. The aspheric surface can eliminate or reduce optical spherical aberration. In the second step, the aspheric surface is divided into equal phase surfaces to obtain multiple equal phase surfaces. Figure 2 As shown, the phase period of the equiphase surface is T, that is, the distance between each two adjacent equiphase surfaces is T. A corresponding partial aspheric surface is included between each two adjacent equiphase surfaces. Each partial aspheric surface is translated to the same plane, such as plane 1, to obtain a focusing lens 202. In the third step, each partial aspheric surface is binarized to obtain a focusing lens 101 with a continuous relief structure.

[0033] Figure 3 This is a schematic diagram of the structure of the focusing lens provided in the embodiment of the present application during the processing. Figure 3 As shown, in the first step, a square material to be processed 301 is selected. In the second step, a standard spherical surface is processed on the rear surface of the material to be processed 301 to obtain a focusing lens 302. In the third step, a binary optical structure is manufactured on the front surface of the focusing lens 302 to obtain a focusing lens 101. Manufacturing a binary optical structure refers to machining a continuous relief structure on the front surface of the focusing lens 302.

[0034] In practical applications, the focusing lens may produce optical spherical aberration. In order to eliminate or reduce the optical spherical aberration, the front surface of the focusing lens has a high curvature, such as Figure 2 The focusing lens 201 in the optical pickup 100 is caused to have a large sagittal height. In the embodiment of the present application, in order to eliminate or reduce the optical spherical aberration generated by the focusing lens 101, the front surface of the focusing lens 101 is a binary optical structure. The sagittal height of the focusing lens 101 can be reduced by the binary optical structure. For example, the sagittal height of the focusing lens 201 is less than or equal to 1 mm. In the embodiment of the present application, by reducing the sagittal height of the focusing lens 101, the size of the optical pickup 100 can be reduced.

[0035] In an embodiment of the present application, the first collimating lens 103 is used to collimate the first light beam. During the collimation process, the first collimating lens 103 may produce chromatic aberration. In order to eliminate or reduce chromatic aberration, the front surface of the first collimating lens 103 includes an aspherical surface or a binary optical structure, and the rear surface of the first collimating lens 103 includes a grating. This is described separately below. Among them, the front surface of the first collimating lens 103 refers to the surface of the first collimating lens 103 receiving the first light beam from the first laser 104. The rear surface of the first collimating lens 103 refers to the surface of the first collimating lens 103 outputting the first light beam.

[0036] In a first example, the front surface of the first collimating lens 103 includes an aspherical surface, and the rear surface of the first collimating lens 103 includes a grating. Figure 4 This is a schematic diagram of the structure of the first collimating lens provided in the embodiment of the present application. Figure 4 As shown in Figure a, when the front surface of the first collimating lens 401 includes an aspheric surface and the rear surface of the first collimating lens 401 does not include a grating, the aspheric surface generates refraction. At this time, the light beam passing through the first collimating lens generates dispersion. For example, the light beams from near to far from the first collimating lens 401 are blue (B), green (G), and red (R). Figure 4As shown in Figure b, when the front surface of the first collimating lens 402 does not include an aspheric surface and the rear surface of the first collimating lens 402 includes a grating, the grating produces diffraction. The grating belongs to a binary optical structure. The binary optical structure has an abnormal dispersion relationship. Therefore, the light beam passing through the first collimating lens will also produce dispersion. For example, from near to far from the first collimating lens 401, they are red (R), green (G) and blue (B). Figure 4 As shown in FIG. c, when the front surface of the first collimating lens 103 includes an aspherical surface and the rear surface of the first collimating lens 103 includes a grating, the dispersion can be offset by combining the two, thereby correcting the chromatic aberration.

[0037] In the second example, the front surface of the first collimating lens 103 includes a binary optical structure, and the rear surface of the first collimating lens 103 includes a grating. Figure 5 This is a schematic diagram of the structure of the collimating lens provided in the embodiment of the present application during the design process. Figure 5 As shown, in the first step, the structure of the collimating lens 501 is designed. The collimating lens 501 is a double-cemented lens. The collimating lens 501 includes a positive lens and a negative lens. The front surface of the positive lens is an aspheric surface. The aspheric surface is used to achieve focusing of the light beam. By gluing two different types of lenses together, the influence of chromatic aberration can be offset. In the second step, the aspheric surface is divided into equal phase surfaces to obtain a plurality of equal phase surfaces. Each two adjacent equal phase surfaces include corresponding partial aspheric surfaces. Each partial aspheric surface is translated to the same plane, such as plane 2. A grating is designed on the back surface of the collimating lens 501 to obtain the collimating lens 502. In the third step, each partial aspheric surface is binarized to obtain a first collimating lens 103 with a continuous relief structure. Figure 6 This is a schematic diagram of the structure of the collimating lens provided in the embodiment of the present application during the processing. Figure 6 As shown, in the first step, a square material to be processed 601 is selected. In the second step, a grating is processed on the rear surface of the material to be processed 601 to obtain a collimating lens 602. In the third step, a binary optical structure is made on the front surface of the collimating lens 602 to obtain a first collimating lens 103.

[0038] According to the aforementioned Figure 2 to Figure 6 It can be seen from the description that the front surface of the first collimating lens 103 and the front surface of the focusing lens 101 have a binary optical structure. The phase order of the binary optical structure refers to the number of steps of the continuous relief structure corresponding to each partial aspheric surface in the binary optical structure. The phase order of the binary optical device is positively correlated with the processing cost and diffraction efficiency of the binary optical device, that is, the larger the phase order, the higher the processing cost of the binary optical device and the higher the diffraction efficiency. Figure 1In the example, the first light beam passes through the first collimating lens 103 once and passes through the focusing lens 101 twice. In the embodiment of the present application, in order to reduce the processing cost and improve the diffraction efficiency, the phase order of the focusing lens 101 can be greater than the phase order of the first collimating lens 103. For example, the phase order of the focusing lens is greater than or equal to 16. The phase order of the first collimating lens is less than or equal to 8.

[0039] In practical applications, the phase period of the isophase surface of a binary optical device is negatively correlated with the processing cost of the binary optical device. The phase period of the isophase surface of a binary optical device is negatively correlated with the diffraction efficiency of the binary optical device. Figure 1 In the example, the first light beam passes through the first collimating lens 103 once and passes through the focusing lens 101 twice. Therefore, in order to reduce processing costs and improve diffraction efficiency, the phase period of the equiphase plane of the focusing lens 101 can be smaller than the phase period of the equiphase plane of the first collimating lens 103. For example, the phase period T of the equiphase plane of the focusing lens 101 is 2πλ. The phase period T of the equiphase plane of the first collimating lens 103 is greater than or equal to 4πλ. λ is the wavelength of the first light beam or a common multiple of the wavelengths. Wherein, when the optical pickup 100 is an optical pickup with a single light source, λ is the wavelength of the first light beam. When the optical pickup 100 is an optical pickup with multiple light sources, λ is the least common multiple of the wavelengths of the multiple light beams. For example, λ is the least common multiple of the wavelength λ1 of the first light beam and the wavelength λ2 of the second light beam.

[0040] Figure 7 This is a second structural diagram of the optical pickup provided in the embodiment of the present application. Figure 7 As shown, in Figure 1 On the basis of , the optical pickup 100 further includes a second laser 701 and a second collimating lens 702. The second laser 701 is used to generate a second light beam (dashed line) and transmit the second light beam to the second collimating lens 702. Figure 7 In the example of , the dashed line represents the first light beam, and the solid line represents the first light beam and the second light beam. The second collimating lens 702 is used to transmit the second light beam to the focusing lens 101 through the intermediate lens group 102. The focusing lens 101 is used to transmit the second light beam to the optical recording medium 106. The second light beam can be used to store or read data on the optical recording medium 106. These are described below.

[0041] In the first example, the second light beam is used to store data on the optical recording medium 106. For example, the second light beam is blue light. The first light beam is red light. The first light beam is focused and tracked on the swing layer of the optical recording medium 106. The first electrical signal obtained by the first detector 105 is used to implement a tracking closed loop. The second light beam follows the first light beam, tracks on the data layer of the optical recording medium 106, and stores data on the data layer.

[0042] In the second example, the second light beam is used to read data on the optical recording medium 106. Figure 7 As shown, the optical pickup 100 further includes a second detector 703. The focusing lens 101 is also used to receive the reflected light beam of the second light beam from the optical recording medium 106. The focusing lens 101 is also used to transmit the reflected light beam of the second light beam to the second detector 703 through the intermediate lens group 102. The second detector 703 is used to convert the reflected light beam of the second light beam into a second electrical signal. The second electrical signal is the data stored in the optical recording medium 106.

[0043] According to the aforementioned Figure 5 and Figure 6 As can be seen from the description, the front surface of the first collimating lens 103 includes a binary optical structure, and the rear surface of the first collimating lens 103 includes a grating. Similarly, the front surface of the second collimating lens 702 can also include a binary optical structure, and the rear surface of the second collimating lens 702 can also include a grating. In practical applications, the red light is focused and tracked on the swing layer of the optical recording medium 106. The blue light is focused on the data layer of the optical recording medium 106. The blue light tracks the red light. Therefore, in the optical pickup 100, the requirements for the diffraction efficiency of the red light are lower, and the diffraction efficiency of the blue light is higher. In addition, the phase order of the binary optical device is positively correlated with the processing cost and diffraction efficiency of the binary optical device. Therefore, when the first light beam is blue light and the second light beam is red light, in order to reduce the processing cost and improve the diffraction efficiency, the phase order of the first collimating lens 103 can be greater than the phase order of the second collimating lens 702.

[0044] In other embodiments, in the optical pickup 100, the diffraction efficiency of red light is less required, and the diffraction efficiency of blue light is more required. Therefore, when the first light beam is blue light and the second light beam is red light, in order to reduce the processing cost, the first collimating lens 103 is a binary optical device, and the second collimating lens 702 is not a binary optical device.

[0045] Figure 8 This is a third structural diagram of the optical pickup provided in the embodiment of the present application. Figure 8 As shown, in Figure 1 Based on the optical pickup 100, the optical pickup 100 further includes a second laser 701, a second collimating lens 702, a magnet 805 and a coil 806. The magnet 805 and the coil 806 constitute an OPU motor. Figure 1As can be seen from the description, the first electrical signal can be used for tracking closed loop. Specifically, the deviation obtained from the first electrical signal can be used to generate a control signal. The OPU motor is used to drive the focusing lens 101 to move radially along the optical recording medium 106 according to the control signal to achieve a tracking closed loop. The second laser 701 is used to generate a second light beam and transmit the second light beam to the second collimating lens 702. The second collimating lens 702 is used to transmit the second light beam to the focusing lens 101 through the intermediate lens group 102. The focusing lens 101 is used to transmit the second light beam to the optical recording medium 106. The second light beam can be used to store or read data on the optical recording medium 106.

[0046] like Figure 8 As shown, in Figure 1 On the basis of, the intermediate lens group 102 includes a beam combiner 801, a beam splitter 802, a reflector 803, a beam expander 804 and a focusing optical element 807. The beam combiner 801 is used to receive the second light beam (dashed line) from the second collimating lens 702, and to receive the first light beam (dotted line) from the first collimating lens 103. The beam combiner 801 is used to combine the first light beam and the second light beam, and transmit the first light beam and the second light beam to the beam splitter 802. The beam splitter 802 is used to reflect the first light beam and the second light beam. The reflector 803 is used to receive the first light beam and the second light beam from the beam splitter 802, and reflect the first light beam and the second light beam to the beam expander 804. The beam expander 804 is used to expand the first light beam and the second light beam, and transmit the first light beam and the second light beam to the focusing lens 101. The focusing lens 101 is used to focus the first light beam and the second light beam to different positions of the optical recording medium 106. The focusing lens 101 is also used to receive the reflected light beam of the first light beam and / or the second light beam from the optical recording medium 106, and transmit the reflected light beam of the first light beam to the focusing optical element 807 through the intermediate lens group 102. The focusing optical element 807 is used to focus the reflected light beam of the first light beam onto the first detector 105. It should be understood that Figure 8 In the example of FIG. 1 , only one detector is illustrated. In practical applications, the optical pickup 100 can further include a second detector 703 . The second detector 703 is used to receive the reflected light beam of the second light beam through the intermediate lens group 102 .

[0047] Fig. 9 This is a fourth structural diagram of an optical pickup provided in an embodiment of the present application. Fig. 9 As shown, in Figure 7On the basis of, the intermediate lens group 102 includes a dichroic mirror 901, a first beam splitter 902 and a second beam splitter 903. The first beam splitter 902 is used to separate the first light beam and the reflected light beam of the first light beam. The second beam splitter 903 is used to separate the second light beam and the reflected light beam of the second light beam. In the transmission direction of the light beam, the dichroic mirror 901 is used to combine the first light beam and the second light beam. In the transmission direction of the reflected light beam, the dichroic mirror 901 is used to separate the reflected light beam of the first light beam and the reflected light beam of the second light beam. Specifically, Fig. 9 In the transmission direction of the light beam, the first light beam output by the first laser 104 passes through the first collimating lens 103, the first beam splitter 902, the dichroic mirror 901 and the focusing lens 101 to reach the optical recording medium 106. The second light beam output by the second laser 701 passes through the second collimating lens 702, the second beam splitter 903, the dichroic mirror 901 and the focusing lens 101 to reach the optical recording medium 106. In the transmission direction of the reflected light beam, the optical recording medium 106 reflects the first light beam and the second light beam. The reflected light beam of the first light beam passes through the focusing lens 101, the dichroic mirror 901 and the first beam splitter 902 to reach the first detector 105. The reflected light beam of the second light beam passes through the focusing lens 101, the dichroic mirror 901 and the second beam splitter 903 to reach the second detector 703.

[0048] The optical pickup provided by the present application is described above, and the optical drive and data processing device provided by the present application are described below. Fig.10 This is a schematic diagram of the structure of the optical drive provided in the embodiment of the present application. Fig.10 As shown, the optical drive 1000 includes a spindle motor 1002, a drive motor 1001 and an optical pickup 100. The spindle motor 1002 is used to carry and rotate the optical recording medium 106. The drive motor 1001 can also be called a sled motor. The drive motor 1001 is used to drive the optical pickup 100 to move along the radial direction of the optical recording medium 106 to read data stored on the optical recording medium 106 and / or store data on the optical recording medium 106. Fig.10 In the embodiment, the axial direction of the optical recording medium 106 is the Y-axis direction. The radial direction of the optical recording medium 106 is the X-axis direction. It should be understood that the description of the optical pickup 100 can be referred to the aforementioned Figures 1 to 9 A description of any graph.

[0049] Fig.11 This is a schematic diagram of the structure of the data processing device provided in the embodiment of the present application. Fig.11As shown, the data processing device 1100 includes a processor 1101 and an optical drive 1000. The optical drive 1000 is used to read data from the optical pickup 100 and / or store data on the optical pickup 100. The processor 1101 can be a central processing unit (CPU), a network processor (NP) or a combination of a CPU and a NP. The processor 1101 can further include a hardware chip or other general-purpose processor. The above-mentioned hardware chip can be an application specific integrated circuit (ASIC), a programmable logic device (PLD) or a combination thereof. The processor 1101 is used to transmit data to the optical drive 1000 and / or receive data from the optical drive 1000. It should be understood that the description of the optical drive 1000 can refer to the description of the aforementioned 10.

[0050] In other embodiments, the data processing device 1100 may further include a memory. The memory may be a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memories. Among them, the non-volatile memory may be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), or a flash memory. The volatile memory may be a random access memory (RAM). The memory is used to store data received from the optical drive 1000 and / or the memory is used to store data transmitted to the optical drive 1000.

[0051] The above are only specific implementation methods of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be covered by the protection scope of the present application.

Claims

1. An optical pickup, characterized in that: The invention comprises a first laser, a first collimating lens, an intermediate lens group, a first detector and a focusing lens, wherein: The first laser is used to generate a first light beam, and transmit the first light beam to the first collimating lens; The first collimating lens is used to transmit the first light beam to the focusing lens through the intermediate lens group; The focusing lens is a binary optical device, and is used to transmit the first light beam to the optical recording medium, receive the reflected light beam of the first light beam from the optical recording medium, and transmit the reflected light beam of the first light beam to the first detector through the intermediate lens group; The first detector is used to convert the reflected light beam of the first light beam into a first electrical signal.

2. The optical pickup device according to claim 1, characterized in that The rear surface of the first collimating lens includes a grating.

3. The optical pickup according to claim 1 or 2, characterized in that: The front surface of the first collimating lens is a binary optical structure.

4. The optical pickup according to claim 2 or 3, characterized in that: The phase order of the focusing lens is greater than the phase order of the first collimating lens.

5. The optical pickup device according to claim 4, characterized in that The phase order of the focusing lens is greater than or equal to 16, and the phase order of the first collimating lens is less than or equal to 8.

6. The optical pickup device according to any one of claims 3 to 5, characterized in that: The phase period of the isophase surface of the focusing lens is smaller than the phase period of the isophase surface of the first collimating lens.

7. The optical pickup device according to claim 6, characterized in that The phase period of the isophase plane of the focusing lens is 2πλ, and the phase period of the isophase plane of the first collimating lens is greater than or equal to 4πλ, where λ is the wavelength of the first light beam or a common multiple of the wavelength.

8. The optical pickup device according to any one of claims 1 to 7, characterized in that: The optical pickup further comprises a second laser and a second collimating lens, wherein: The second laser is used to generate a second light beam, and transmit the second light beam to the second collimating lens; The second collimating lens is used to transmit the second light beam to the focusing lens through the intermediate lens group; The focusing lens is used to transmit the second light beam to the optical recording medium.

9. The optical pickup device according to claim 8, characterized in that The front surface of the second collimating lens is a binary optical structure.

10. The optical pickup device according to claim 9, characterized in that The first light beam is blue light, the second light beam is red light, and the phase order of the first collimating lens is greater than the phase order of the second collimating lens.

11. The optical pickup device according to claim 8, characterized in that The first light beam is blue light, the second light beam is red light, and the front surface of the second collimating lens is not a binary optical structure.

12. The optical pickup device according to any one of claims 1 to 11, characterized in that: The sagittal height of the focusing lens is less than or equal to 1 mm.

13. An optical drive, characterized in that: The optical pickup device comprises a spindle motor, a drive motor and any one of claims 1 to 12, wherein: The spindle motor is used to carry and rotate the optical recording medium; The driving motor is used to drive the optical pickup to move along the radial direction of the optical recording medium to read data stored on the optical recording medium and / or store data on the optical recording medium.

14. A data processing device, characterized in that: The optical drive comprises a processor and the optical drive as claimed in claim 13, wherein the processor is used to transmit data to the optical drive or receive data from the optical drive.

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