Optical pickup, optical disc drive and data processing device

Abstract

The present application is applied to the field of optical storage. Provided is an optical pickup. The optical pickup 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 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 the first light beam to the focusing lens through the intermediate lens group; the focusing lens is a binary optical element; the focusing lens is used for transmitting the first light beam to an optical recording medium and receiving a reflected light beam of the first light beam from the optical recording medium; the focusing lens is further used for transmitting the reflected light beam of the first light beam to the first detector through the intermediate lens group; and the first detector is used for converting the reflected light beam of the first light beam into a first electrical signal. In the technical solution provided by the present application, by means of using a binary optical element as the focusing lens, the sag of the focusing lens can be reduced, and thus the size of the optical pickup can also be reduced.

Description

Optical pickups, optical drives, and data processing equipment

[0001] This application claims priority to the Chinese patent application filed with the State Intellectual Property Office on July 26, 2023, with application number 202310932030.5 and invention name “Optical pickup, optical drive and data processing equipment”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] 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

[0003] An optical pickup is an optical pickup device that is placed opposite 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. 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.

[0004] Summary of the Invention

[0005] 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.

[0006] The first aspect of 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.

[0007] 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 height of the first collimating lens can be reduced, thereby further reducing the size of the optical pickup.

[0008] In an optional embodiment of the first aspect, the rear surface of the first collimating lens includes a grating. In practical applications, the effects of chromatic aberration can be reduced by using a collimating lens composed of two lenses. The two lenses are made of different materials. In the present application, the first collimating lens processed from a single material can reduce the effects of chromatic aberration by using a grating and a binary optical structure. Furthermore, the first collimating lens processed from a single material can reduce the effects of ambient temperature, thereby improving the reliability of the optical pickup.

[0009] In one optional embodiment 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 a binary optical device is positively correlated with its processing cost and diffraction efficiency. During 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, a balance between processing cost and diffraction efficiency can be achieved.

[0010] 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.

[0011] In an optional embodiment 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, a balance between processing cost and diffraction efficiency can be maintained.

[0012] In an optional embodiment of the first aspect, a phase period of the isophase surface of the focusing lens is 2πλ. A phase period of the isophase surface of the first collimating lens is greater than or equal to 4πλ. λ is a wavelength of the first light beam or a common multiple of the wavelength.

[0013] In an optional embodiment of the first aspect, the optical pickup further includes a second laser and a second collimating lens. The second laser is configured to generate a second light beam and transmit the second light beam to the second collimating lens. The second collimating lens is configured to transmit the second light beam to the focusing lens via the intermediate lens group. The focusing lens is configured to transmit the second light beam to the optical recording medium.

[0014] 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 height of the second collimating lens can be reduced, thereby further reducing the size of the optical pickup.

[0015] In an optional embodiment 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 the red light. Therefore, in the optical pickup, the diffraction efficiency requirements for red light are lower, and the diffraction efficiency requirements for blue light are 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 processing cost and diffraction efficiency can be controlled.

[0016] In an optional embodiment 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 does not have 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 requirements for red light are lower, while the diffraction efficiency requirements for blue light are higher. Therefore, when the front surface of the second collimating lens has a binary optical structure, and the front surface of the second collimating lens does not have a binary optical structure, the balance between processing cost and diffraction efficiency can be controlled.

[0017] In an optional manner of the first aspect, the sagittal height of the focusing lens is less than or equal to 1 mm.

[0018] A 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 embodiment of the first aspect. The spindle motor is configured to carry and rotate an optical recording medium. The drive motor is configured to drive the optical pickup to move radially along the optical recording medium to read data stored on the optical recording medium and / or store data on the optical recording medium.

[0019] A 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 configured to transmit data to or receive data from the optical drive. The optical drive is configured to read data stored on an optical recording medium and / or store data on the optical recording medium. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] FIG1 is a first structural diagram of an optical pickup provided in an embodiment of the present application;

[0021] FIG2 is a schematic diagram of the structure of a focusing lens during the design process provided in an embodiment of the present application;

[0022] FIG3 is a schematic diagram of the structure of a focusing lens during processing according to an embodiment of the present application;

[0023] FIG4 is a schematic structural diagram of a first collimating lens provided in an embodiment of the present application;

[0024] FIG5 is a schematic diagram of the structure of a collimating lens provided in an embodiment of the present application during the design process;

[0025] FIG6 is a schematic structural diagram of a collimating lens provided in an embodiment of the present application during processing;

[0026] FIG7 is a second structural diagram of the optical pickup provided in an embodiment of the present application;

[0027] FIG8 is a third structural diagram of the optical pickup provided in an embodiment of the present application;

[0028] FIG9 is a fourth structural diagram of an optical pickup provided in an embodiment of the present application;

[0029] FIG10 is a schematic diagram of the structure of an optical drive provided in an embodiment of the present application;

[0030] FIG11 is a schematic diagram of the structure of a data processing device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0031] 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 sag 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 this 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 order. In addition, for the sake of simplicity and clarity, reference numbers and / or letters are repeated in multiple figures of this application. Repetition does not indicate a strict limit relationship between various embodiments and / or configurations.

[0032] The optical pickup provided in this application is used in the field of optical storage. The optical pickup includes a light source, a photodetector, and a lens system. The lens system includes multiple optical elements. The lens system can be used to collimate and redirect a light beam, and eliminate or reduce optical aberrations. The size of the lens system is closely related to the size of the optical pickup. Therefore, reducing the size of the lens system is a technical problem that urgently needs to be solved.

[0033] To this end, the present application provides an optical pickup. FIG1 is a first structural schematic diagram of the optical pickup provided in an embodiment of the present application. As shown in FIG1 , 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 has a binary optical structure. In the embodiment of the present application, the front surface of the focusing lens 101 refers to the surface on which the focusing lens 101 receives the first light beam from the intermediate lens group 102. The rear surface of the focusing lens 101 refers to the surface on which the focusing lens 101 outputs the first light beam. The focusing lens 101 is used to eliminate spherical aberration in optical aberrations, transmit the first light beam to the optical recording medium 106, and receive a reflected light beam of the first light beam from the optical recording medium 106. The optical recording medium is an optical disc. An 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 via 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 on the data layer of the optical recording medium 106, the first electrical signal represents the data stored in the optical recording medium 106. When the first light beam tracks on 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 in 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 where the first light beam is irradiated onto the optical recording medium 106 according to the deviation.

[0034] Figure 2 is a schematic diagram of the structure of the focusing lens provided in an embodiment of the present application during the design process. As shown in Figure 2, 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 to form 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 a plurality of equal phase surfaces. As shown in Figure 2, the phase period of the equal phase surface is T, that is, the distance between each two adjacent equal phase surfaces is T. Each two adjacent equal phase surfaces include corresponding partial aspheric 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.

[0035] Figure 3 is a schematic diagram of the structure of a focusing lens during processing according to an embodiment of the present application. As shown in Figure 3, in the first step, a square material 301 is selected for processing. In the second step, a standard spherical surface is machined on the rear surface of the material 301 to obtain a focusing lens 302. In the third step, a binary optical structure is fabricated on the front surface of the focusing lens 302 to obtain the focusing lens 101. Fabricating the binary optical structure involves machining a continuous relief structure on the front surface of the focusing lens 302.

[0036] 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 higher curvature, such as the focusing lens 201 in Figure 2, which results in a larger sagitta of the focusing lens. In an embodiment of the present application, in order to eliminate or reduce the optical spherical aberration produced by the focusing lens 101, the front surface of the focusing lens 101 is a binary optical structure. Through the binary optical structure, the sagitta of the focusing lens 101 can be reduced, for example, the sagitta of the focusing lens 201 is less than or equal to 1 mm. In an embodiment of the present application, by reducing the sagitta of the focusing lens 101, the size of the optical pickup 100 can be reduced.

[0037] 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 aspheric surface or a binary optical structure, and the rear surface of the first collimating lens 103 includes a grating. These are described separately below. The front surface of the first collimating lens 103 refers to the surface of the first collimating lens 103 that receives 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 that outputs the first light beam.

[0038] In the first example, the front surface of the first collimating lens 103 includes an aspheric surface, and the rear surface of the first collimating lens 103 includes a grating. Figure 4 is a schematic structural diagram of the first collimating lens provided in an embodiment of the present application. As shown in Figure a of Figure 4, 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 produces refraction. In this case, the light beam passing through the first collimating lens will produce dispersion. For example, from near to far from the first collimating lens 401, the colors are blue (B), green (G), and red (R). As shown in Figure b of Figure 4, 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 is a binary optical structure. Binary optical structures have an anomalous 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, the colors are red (R), green (G), and blue (B). As shown in FIG. 4 c , when the front surface of the first collimating lens 103 includes an aspheric 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 chromatic aberration.

[0039] 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 is a schematic diagram of the structure of the collimating lens provided in an embodiment of the present application during the design process. As shown in Figure 5, 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 focus 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 multiple equal phase surfaces. Each two adjacent equal phase surfaces include corresponding partial aspheric surfaces. Each partial aspheric surface is translated to the same plane, for example, plane 2. A grating is designed on the rear surface of the collimating lens 501 to obtain the collimating lens 502. In the third step, each partial aspheric surface is binarized to obtain the first collimating lens 103 with a continuous relief structure. Figure 6 is a schematic diagram of the structure of the collimating lens provided in an embodiment of the present application during processing. As shown in Figure 6, 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 fabricated on the front surface of the collimating lens 602 to obtain the first collimating lens 103.

[0040] According to the description of Figures 2 to 6 above, it can be seen 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. In the example of Figure 1, the first light beam passes through the first collimating lens 103 once and passes through the focusing lens 101 twice. In an embodiment of the present application, in order to reduce processing costs and improve 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.

[0041] 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. In the example of Figure 1, 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 isophase surface of the focusing lens 101 can be smaller than the phase period of the isophase surface of the first collimating lens 103. For example, the phase period T of the isophase surface of the focusing lens 101 is 2πλ. The phase period T of the isophase surface 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. 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.

[0042] FIG7 is a second structural schematic diagram of the optical pickup provided in an embodiment of the present application. As shown in FIG7 , based on FIG1 , 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. In the example of FIG7 , the dotted 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. Each of these is described below.

[0043] 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 tracks 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 closed tracking 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.

[0044] In the second example, the second light beam is used to read data from the optical recording medium 106. In this case, as shown in FIG7 , the optical pickup 100 further includes a second detector 703. The focusing lens 101 is further configured to receive a reflected light beam of the second light beam from the optical recording medium 106. The focusing lens 101 is further configured to transmit the reflected light beam of the second light beam to the second detector 703 via the intermediate lens group 102. The second detector 703 is configured to convert the reflected light beam of the second light beam into a second electrical signal. The second electrical signal represents the data stored in the optical recording medium 106.

[0045] As shown in the description of Figures 5 and 6 above, 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 actual applications, red light is focused and tracked on the swing layer of the optical recording medium 106. 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 diffraction efficiency requirements for red light are lower, while the diffraction efficiency requirements for blue light are higher. In addition, the phase order of a binary optical device is positively correlated with its processing cost and diffraction efficiency. Therefore, when the first light beam is blue light and the second light beam is red light, to reduce processing costs and improve diffraction efficiency, the phase order of the first collimating lens 103 can be greater than the phase order of the second collimating lens 702.

[0046] In other embodiments, in the optical pickup 100, the diffraction efficiency requirement for red light is lower, while the diffraction efficiency requirement for blue light is higher. Therefore, when the first light beam is blue light and the second light beam is red light, to reduce processing costs, the first collimating lens 103 is a binary optical device, while the second collimating lens 702 is not a binary optical device.

[0047] FIG8 is a third schematic structural diagram of the optical pickup provided in an embodiment of the present application. As shown in FIG8 , in addition to FIG1 , 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 coil 806 constitute an OPU motor. As described above with reference to FIG1 , the first electrical signal can be used for closed-loop tracking. 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 closed-loop tracking. The second laser 701 is used to generate a second light beam, which is transmitted to the second collimating lens 702. The second collimating lens 702 is used to transmit the second light beam to the focusing lens 101 via 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.

[0048] As shown in Figure 8, based on Figure 1, 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 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 further configured to receive the reflected beam of the first light beam and / or the second light beam from the optical recording medium 106, and transmit the reflected beam of the first light beam to the focusing optical element 807 via the intermediate lens group 102. The focusing optical element 807 is configured to focus the reflected beam of the first light beam onto the first detector 105. It should be understood that in the example of FIG. 8 , only one detector is illustrated. In actual applications, the optical pickup 100 can further include a second detector 703. The second detector 703 is configured to receive the reflected beam of the second light beam via the intermediate lens group 102.

[0049] FIG9 is a fourth structural schematic diagram of the optical pickup provided in an embodiment of the present application. As shown in FIG9 , based on FIG7 , 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, in FIG9 , 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 before reaching 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 before reaching the optical recording medium 106. The optical recording medium 106 reflects the first and second light beams in the direction of transmission of the reflected light beams. 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 before reaching 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 before reaching the second detector 703.

[0050] The optical pickup provided by the present application is described above. The optical drive and data processing device provided by the present application are described below. Figure 10 is a schematic structural diagram of the optical drive provided by an embodiment of the present application. As shown in Figure 10, 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. In Figure 10, 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 refer to the description of any of the aforementioned Figures 1 to 9.

[0051] Figure 11 is a structural diagram of a data processing device provided in an embodiment of the present application. As shown in Figure 11, 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 an 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.

[0052] 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. 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.

[0053] The above is only a specific implementation method of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with this technical field can easily think of changes or replacements within the technical scope disclosed in this 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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