M253044 捌、新型說明： 【新型所屬之技術領域】 本創作是關於電磁致動器（driving device)之結構，特別是一種使用 於光學讀取頭（opticalpickup)之物鏡（objectivelens)的電磁致動器，相 對於一紅轉的光碟記錄媒體’作垂直於物鏡光軸（〇pticai axis)的尋執 (tracking，T)偏差修正及平行於物鏡光軸的聚焦（foeusing，F)偏差修正。 【先前技術】 一種使用光學記錄媒體之可記錄或可重複記錄裝置，如光碟機 (CD-ROM)或磁性光碟機（MO)，已被當作為記錄資料的重要工具。在 這些光碟機的機構中都包括有一光學讀取單元，用來發射光束至光學 記錄媒體的訊號記錄表面及偵測由光學記錄媒體所反射之回饋雷射 光。光學讀取頭中具有一用來發射光束之光源，如半導體雷射 (semiconductorlaser)，及一用來聚焦該光束於記錄媒體之物鏡。此外， 光學讀取頭中還需要一致動器，用來驅動該物鏡，作平行該物鏡光轴 之聚焦偏差修正及垂直該物鏡光轴之尋軌偏差修正，使雷射光束聚焦 於記錄媒體的訊號記錄區域中與正域地追縱記錄軌跡。 目前大部分的致動器都使用電磁動力方式來驅動物鏡作聚焦偏差 修正與尋執偏差修正。因此，用以修正聚焦偏差之聚焦線圈（focusing c〇U)與尋軌偏差之尋執線圈（tracking coil)被使用於物鏡之電磁致動器 中。聚焦線圈與物鏡之光轴垂直，可使得物鏡作上下修正移動，而尋 執線圈與物鏡之光轴平行，可使得物鏡作左右修正移動。 5 隨著光學記錄媒體的讀寫速度愈來愈快，驅動物鏡作聚焦修正與 尋轨修正之電磁致動器的反應速度與靈敏度（sensitivity)亦要求愈來愈 南。美國專利5,627,687揭露了一種電磁致動器之結構，其結構中的聚 焦線圈與尋軌線圈的使用效率只達30〜40%。如欲提高此電磁致動器結 構的反應速度與靈敏度’須採用高價位之高磁機能磁石或材質輕且成 本高之電磁致動器，此將造成成本之提高。 【新型内容】 本創作係提供一種應用於光學讀取頭物鏡之電磁致動器，包含有 一物鏡、一物鏡承載座、一對焦線圈、一尋軌線圈、一輔助磁力裝置、 一基座、複數個線狀彈性體及一上蓋。物鏡承載座用來承載物鏡及固 定對焦線圈與尋執線圈。基座位於此電磁致動器之最下方，具有直立 的部分用來固定輔助磁力裝置。輔助磁力裝置係以複數個磁石（magnet) 組成並作為辅助磁力的來源，磁石們之間以一空間區隔開來並構成一 封閉磁力線系統。線狀彈性體的一端與物鏡承載座連接，另一端則連 接至基座，用來支撐懸予該物鏡承載座作對焦修正移動與尋軌修正移 動。對焦線圈與尋軌線圈之間互相呈現直交（orthogonal)狀態，對焦線 圈與物鏡之光轴呈垂直狀態，而尋軌線圈與物鏡之光轴呈平行狀態。’ 對焦線圈與尋軌線圈位於辅助磁力裝置之封閉磁力線系統中，隨著輸 入電流方向之變化進而產生電磁力，使得物鏡與物鏡承載座作上下與 左右移動之對焦修正與尋軌修正。上蓋位於此電磁致動器之最上方’ 具有導磁作用及保護對焦線圈、尋軌線圈與磁力輔助裝置。 M253044 本創作中，構成磁力辅助裝置之複數個磁石係直立固定於基座之 直立的部分’其排列方式為磁極相同的磁石以一空間區隔開來呈平行 方式排列，磁極相異的磁石則互相接鄰呈垂直方式排列，如此即構成 一封閉磁列線系統。對焦線圈與尋軌線圈係電線以同一方向纏繞而 成，其線圈兩側皆位於辅助磁力裝置之封閉磁力線系統中，使得對焦 線圈與尋軌線圈的使用效率，不須要使用高價位之高磁機能磁石或材 質輕之物鏡承載座，即可達到50%以上，進而提高電磁致動器之反應 速度與靈敏度。 茲配合下列圖示、實施例之詳細說明及專利申請範圍，將上述及 本創作之其他目的與優點詳述於後。 【實施方式】 第一圖為本創作之電磁致動器的結構示意圖。物鏡13固定於物鏡 承載座12之前端，辅助磁力裝置、對焦線圈lla與尋執線圈丨化位於 物鏡承載座12之空格内。基座16位於物鏡承載座12之下方，上蓋15 則位於物鏡承載座12之上方。四個線狀彈性體14各位於物鏡承載座 之兩側，每一側各兩個，其一端與物鏡承載座12連接，另一端連接至 基座16。 辅助磁力裝置係以四個磁石所構成，磁石A l〇a位於靠近物鏡13 之一側，而磁石B 10b隔著對焦線圈11a與尋執線圈llb位於相對之另 一側’磁石C 10c及磁石D 10d與磁石A 10a及磁石B 10b呈垂直狀態， 各位於尋軌線圈lib之兩側。磁石A 10a及磁石B 10b以同一磁極面對 7 面直立’而磁石C 10c及磁石D lOd以另外同一磁極面對面直立，即磁 石A 10a及磁石B 10b以N極相對，而磁石C 10c及磁石D l〇d則須以 S極相對，反之亦可。因此磁石a 10a、磁石b i〇b、磁石c l〇c及磁石 D 10d形成一封閉磁力線系統。 尋執線圈lib位於對焦線圈ua與磁石a〜D 10a〜d之内，與物鏡M253044 新型 Description of the new type: [Technical field to which the new type belongs] This creation is about the structure of a driving device, especially an electromagnetic actuator for objective lenses of an optical pickup With respect to a red-turned optical disc recording medium, correction for tracking (T) deviation perpendicular to the optical axis of the objective lens (Tpticai axis) and correction for focus (Feusing) deviation parallel to the optical axis of the objective lens are made. [Prior Art] A recordable or repeatable recording device using an optical recording medium, such as a compact disc drive (CD-ROM) or a magnetic compact disc drive (MO), has been used as an important tool for recording data. The optical disc drive mechanism includes an optical reading unit for emitting a light beam to a signal recording surface of an optical recording medium and detecting a feedback laser light reflected by the optical recording medium. The optical pickup head has a light source for emitting a light beam, such as a semiconductor laser, and an objective lens for focusing the light beam on a recording medium. In addition, an actuator is needed in the optical pickup to drive the objective lens to correct the focus deviation parallel to the optical axis of the objective lens and to correct the tracking deviation perpendicular to the optical axis of the objective lens, so that the laser beam is focused on the recording medium. Track the track in the signal recording area with the positive area. At present, most of the actuators use electromagnetic power to drive the objective lens for focus deviation correction and seek deviation correction. Therefore, a focusing coil for correcting focus deviation and a tracking coil for tracking deviation are used in the electromagnetic actuator of the objective lens. The focus coil is perpendicular to the optical axis of the objective lens, which allows the objective lens to move up and down, while the seek coil is parallel to the optical axis of the objective lens, which allows the objective lens to move left and right. 5 As the read and write speeds of optical recording media become faster, the response speed and sensitivity of electromagnetic actuators that drive the objective lens for focus correction and tracking correction are also required to become more and more south. U.S. Patent 5,627,687 discloses a structure of an electromagnetic actuator in which the use efficiency of the focus coil and the tracking coil is only 30 to 40%. To increase the response speed and sensitivity of this electromagnetic actuator structure, a high-priced high-magnetism magnet or a lightweight and cost-effective electromagnetic actuator must be used, which will increase the cost. [New content] This creative system provides an electromagnetic actuator applied to an optical pickup objective lens, including an objective lens, an objective lens holder, a focusing coil, a tracking coil, an auxiliary magnetic device, a base, and a plurality of Linear elastic bodies and an upper cover. The objective lens holder is used to carry the objective lens and fixed focus coil and seek coil. The base is located at the bottom of the electromagnetic actuator and has an upright portion for fixing the auxiliary magnetic device. The auxiliary magnetic device is composed of a plurality of magnets and serves as a source of auxiliary magnetic force. The magnets are separated by a space and constitute a closed magnetic field line system. One end of the linear elastic body is connected to the objective lens holder, and the other end is connected to the base for supporting the objective lens holder for focus correction movement and tracking correction movement. The focusing coil and the tracking coil are in an orthogonal state with each other. The focusing coil is perpendicular to the optical axis of the objective lens, and the tracking coil and the optical axis of the objective lens are parallel. ’The focus coil and tracking coil are located in the closed magnetic field line system of the auxiliary magnetic device. As the direction of the input current changes, an electromagnetic force is generated, which causes the objective lens and the objective lens holder to perform focus correction and tracking correction of up and down movement. The upper cover is located on the top of this electromagnetic actuator, and has a magnetic permeability and protects the focus coil, tracking coil and magnetic auxiliary device. M253044 In this work, a plurality of magnets that form a magnetic auxiliary device are fixed upright on the upright part of the base. The arrangement is such that magnets with the same magnetic poles are arranged in a spaced apart manner in parallel, and magnets with different magnetic poles are They are arranged next to each other in a vertical manner, thus forming a closed magnetic column line system. The focusing coil and the tracking coil are wound in the same direction, and both sides of the coil are located in the closed magnetic field line system of the auxiliary magnetic device, so that the use of the focusing coil and the tracking coil is efficient without the need for high-priced high-magnetism functions. Magnets or light-weight objective lens holders can reach more than 50%, thereby improving the response speed and sensitivity of electromagnetic actuators. In conjunction with the following drawings, detailed description of the embodiments and the scope of patent applications, the above and other purposes and advantages of this creation will be described in detail below. [Embodiment] The first figure is a schematic structural diagram of an electromagnetic actuator created. The objective lens 13 is fixed to the front end of the objective lens holder 12, and the auxiliary magnetic device, the focus coil 11a and the seek coil are located in the space of the objective lens holder 12. The base 16 is located below the objective lens holder 12, and the upper cover 15 is located above the objective lens holder 12. The four linear elastic bodies 14 are located on both sides of the objective lens holder, two on each side, one end of which is connected to the objective lens holder 12, and the other end is connected to the base 16. The auxiliary magnetic device is composed of four magnets. The magnet A 10a is located on one side close to the objective lens 13, and the magnet B 10b is located on the opposite side through the focusing coil 11a and the seek coil 11b. The magnet C 10c and the magnet D 10d is perpendicular to magnet A 10a and magnet B 10b, and is located on both sides of the tracking coil lib. Magnet A 10a and magnet B 10b stand up to 7 faces with the same magnetic pole facing each other, and magnet C 10c and magnet D lOd stand up to each other with the same magnetic pole facing each other, that is, magnet A 10a and magnet B 10b face N, and magnet C 10c and magnet D l〇d must be opposite with S pole, and vice versa. Therefore, magnets a 10a, magnets b 10b, magnets c 10c, and magnets D 10d form a closed magnetic field line system. The seek coil lib is located between the focus coil ua and the magnets a ~ D 10a ~ d, and the objective lens
I 13的光轴呈平行狀態，且尋軌線圈llb的磁力線與物鏡13的光轴為垂 直狀態。對焦線圈11a位於磁石A 10a與磁石B 10b之内，及磁石C 10c、 磁石D 10d與尋軌線圈lib之外，與物鏡13的光轴呈垂直狀態，其磁 力線與物鏡13的光轴為平行狀態。對焦線圈ua與尋軌線圈ub的磁 力線互相垂直，因此可使得物鏡承載座12作聚焦方向（如第一圖中的 F方向)與尋軌方向（如第一圖中的τ方向)的修正移動。對焦線圈iia 與尋軌線圈lib係使用單一電線以同一方向纏繞而成。 第二圖為本創作電磁致動器的結構爆炸示意圖。基座16具有四個 直立的部分17a〜d ,用來固定磁石A〜D 10a〜l〇d。對焦線圈ila、尋軌 線圈lib與物鏡13則固定於物鏡承載座12上。上蓋15的材質為具有 導磁作用之輛鐵（yoke)與物鏡承載座12相連結。線狀彈性體14具有 彈性，其與物鏡承載座12形成一彈性懸吊系統，當對焦線圈Ua與尋 軌線圈iib產生電磁作用時，此彈性懸吊系統帶動物鏡13作聚焦方向 與尋軌方向之修正。 第三圖為辅助磁力裝置與線圈相對位置之上視圖。磁石A 1〇a與磁 石B 10b各位於對焦線圈lla之兩側，磁石c 1〇c與磁石〇 1〇d則各位 M253044 於尋軌線圈lib之兩側。磁石A〜D 10a〜d固定於基座16之直立的部分 17A〜D上。對焦線圈11a包圍著尋軌線圈lib與磁石C〜D l〇c〜d與尋 軌線圈11b互相垂直。當對焦線圈lla通入順時針方向的電流時，會產 生向下運動的電磁力，相反地，當通入的為逆時針方向的電流時，會 產生向上運動的電磁力。 第四圖為辅助磁力裝置與線圈相對位置之側視圖。當尋軌線圈Ub 通入順時針方向的電流時，會產生向側邊運動的電磁力，相反地，當 通入的為逆時針方向的電流時，會產生向另一側邊運動的電磁力。 惟，以上所述者，僅為本創作之較佳實施例而已，當不能以此限 疋本創作實施之範®。即大驗本創作_請專繼贿作之均等變化 與修飾，皆應仍屬本創作專利涵蓋之範圍内。 M253044 【圖式簡單說明】 第一圖為本創作之電磁致動器的結構示意圖； 第二圖為本創作電磁致動器的結構爆炸示意圖； 第三圖為輔助磁力裝置與線圈相對位置之上視圖; 第四圖為輔助磁力裝置與線圈相對位置之側視圖。 圖號說明： 11a對焦線圈 12物鏡承載座 14線狀彈性體 16基座 10a〜d磁石A〜D lib尋執線圈 13物鏡 15上蓋 17a〜d直立的部分The optical axis of I 13 is in a parallel state, and the magnetic field lines of the tracking coil 11b and the optical axis of the objective lens 13 are in a vertical state. The focusing coil 11a is located within the magnets A 10a and B 10b, and the magnets C 10c, D 10d and the tracking coil lib are perpendicular to the optical axis of the objective lens 13, and the magnetic field lines are parallel to the optical axis of the objective lens 13. status. The magnetic field lines of the focusing coil ua and the tracking coil ub are perpendicular to each other, so that the objective lens holder 12 can be moved in a corrective direction (such as the F direction in the first figure) and the tracking direction (such as the τ direction in the first figure) . The focus coil iia and the tracking coil lib are formed by winding a single wire in the same direction. The second picture is the structural explosion diagram of the electromagnetic actuator. The base 16 has four upright portions 17a ~ d for fixing the magnets A ~ D 10a ~ 10d. The focus coil ila, the tracking coil lib, and the objective lens 13 are fixed on the objective lens holder 12. The material of the upper cover 15 is a yoke with magnetic permeability and is connected to the objective lens carrier 12. The linear elastic body 14 has elasticity, and forms an elastic suspension system with the objective lens bearing base 12. When the focusing coil Ua and the tracking coil iib generate an electromagnetic effect, the elastic suspension system includes an animal lens 13 for focusing direction and tracking direction Amendments. The third figure is a top view of the relative position of the auxiliary magnetic device and the coil. Magnet A 10a and magnet B 10b are located on both sides of the focus coil 11a, and magnets c 10c and magnet 0 1d are on each side of the tracking coil lib. The magnets A to D 10a to d are fixed to the upright portions 17A to D of the base 16. The focus coil 11a surrounds the tracking coil lib and the magnets C to D10c to d and the tracking coil 11b perpendicular to each other. When a current in the clockwise direction is applied to the focus coil 11a, an electromagnetic force moving downward is generated. On the contrary, when a current is applied in the counterclockwise direction, an electromagnetic force moving upward is generated. The fourth figure is a side view of the relative position of the auxiliary magnetic device and the coil. When the tracking coil Ub passes a current in a clockwise direction, it will generate an electromagnetic force moving to the side. On the contrary, when the current passing in a counterclockwise direction will generate an electromagnetic force moving to the other side. . However, the above is only the preferred embodiment of this creation, and it should not be limited to the scope of this creation. That is, the large-scale version of this creation_ Please follow the equal changes and modifications of the bribes, which should still fall within the scope of this creation patent. M253044 [Brief description of the diagram] The first picture is the structural schematic diagram of the electromagnetic actuator of the creation; the second picture is the structural explosion diagram of the electromagnetic actuator of the creation; the third picture is above the relative position of the auxiliary magnetic device and the coil View; The fourth figure is a side view of the relative position of the auxiliary magnetic device and the coil. Drawing number description: 11a focusing coil 12 objective lens holder 14 linear elastic body 16 base 10a ~ d magnet A ~ D lib seek coil 13 objective lens 15 upper cover 17a ~ d upright part