591199 發明鱗:明二:姻 (#明說明應敘明：發明所屬之技術領域、1前技術、内容、實施方式及圖式簡單麗觸) 【發明所屬之技術領域】 本發明係關於一種可量測五自由度訊號系統，特別是指 一種利用光柵繞射原理與光干涉原理，所建立的可量測五自 由度訊號系統。 【先前技術】591199 Scales of Invention: Ming II: Marriage (# 明 解 应 描述 明: The technical field to which the invention belongs, 1 pre-technology, content, implementation, and simple drawings) [Technical field to which the invention belongs] The present invention relates to a kind of The five-degree-of-freedom signal system is measured, in particular, a five-degree-of-freedom signal system that is established using the principle of grating diffraction and optical interference. [Prior art]
一般精密平台運動是多自由度方位變動且影響著各目 標產生誤差，實際運動時，會產生六自由度誤差包括三個線 位移誤差紅Αν’Δζ與三個角位移俯仰、搖擺、滾動誤差，由於 運動平台是經由線性元件、旋轉平台及其它元件經設計組裝 而具有多自由度運動，機器中之各種運動平台的特性將影響 整台機器的精度與加工產品的品質，被加工工件的定位、精 密零件的安裝及目標物體在空間運動位置和姿態都需要多 至=個自由度的量測與調整或控制；因此對多自由度的檢測 需提出更高要求，而所缺乏的即是能同時量測工件、零部件 或目標物體在空間的多個自由度。 α 右以HP干涉儀而言 丹一次只能重取Generally, the precision platform movement is a multi-degree-of-freedom azimuth change and affects each target to generate errors. In actual movement, a six-degree-of-freedom error will be generated, including three linear displacement errors, red Αν'Δζ, and three angular displacement pitch, roll, and roll errors. Because the motion platform is designed and assembled with linear components, rotary platforms and other components to have multiple degrees of freedom, the characteristics of the various motion platforms in the machine will affect the accuracy of the entire machine and the quality of the processed product. The installation of precision parts and the position and attitude of the target object in space need to be measured and adjusted or controlled with up to = degrees of freedom; therefore, higher requirements are required for the detection of multiple degrees of freedom, and what is lacking is the ability to simultaneously Measure multiple degrees of freedom of a workpiece, component, or target in space. α Right as far as the HP interferometer is concerned, Dan can only be retrieved once
—一. γ叹乃狹產 因此在量測所有誤差時需更換不同量測架構，儀器的安裝 參考軸的對準亦需個別校正，每次重新校正所量取的實際 測路徑並無法與前次路#完全相同，多次校正亦產生誤^ 量測耗時而且增加量測不確定性，而自動視準儀器_ 度^具有高解析度，但整體架構太重不適合安裝機器上倒 上量測。 光學尺的發展上近年來結合光栅繞射與干涉原理' 刀割技術與二維光栅製造的技術發展，目前已有光學尺，如中 6 591199 華民國發明專利證號：99283，專利名稱：對光栅缺陷與對 _ 位不準具有高容許度之繞射光柵線性光學尺，其中，可提供 二維定位且解析度可達奈米級，雖然二維光學尺架設容易解 析度高，但只能提供二維訊號，對於精密運動定位多自由度 誤差無法同時提供；若量測系統每次只僅能檢測一或兩項誤 差’則要將全部誤差量測完畢，其所需時間愈長，環境變化 也越來越難測，量測不確定度將隨時間而增加。 所以在檢測線性平台及X、γ運動平台的量測儀器上， 無論量測儀器是雷射干涉儀、光學尺、自動視準儀或電子水 麵 平移等，皆只能一次量取一個或二個自由度誤差，卻無法同 時一次量取五自由度誤差，致使量測的工作更無效率。 由此可見，上述習用物品仍有諸多缺失，實非一良善之 设計者，而亟待加以改良。 本案發明人鑑於上述習用光學尺結合光栅繞射與干涉 原理與電子分割技術所衍生的各項缺點，乃亟思加以改良創 新，並經多年苦心孤詣潛心研究後，終於成功研發完成本件 可量測五自由度訊號系統。 【發明目的】 _ 本發月之目的即在於k供一種可量測五自由度訊號系 統，其中該雷射二極體與一般的雷射一樣，其光波具有高度 的指向性與同調性，但是卻更能達到有較小的體積與更大的 效率。 本發明之次一目的係在於提供一種可量測五自由度訊 號系統，其中该半反射鏡在正負一階繞射光入射時，產生穿 透光及反射光，而穿透光及反射光的光強度皆只有入射光強 度的一半。 7 591199 本發明之另一目的係在於提供一種可量測五自由度訊 號系統，其中該干涉鏡能使兩道正負一階反射光疊加形成一 干涉光’因而付到相應隨之都卜勒（Dopp 1 er )頻移大小變 化的相移信號變化。 本發明之又一目的係在於提供一種可量測五自由度訊 號系統’其中透鏡組係由多個透鏡組合而成，藉此調整干涉 條紋大小，使其與光電二極體陣列的幾何形狀得以相配合。 【内容】 可達成上述發明目的之可量測五自由度訊號系統，包括 有： 一雷射一極體，係k供雷射光束入射至後述之反射鏡； 一反射鏡，係接收雷射光束反射至後述之光柵； 一反射式光栅，於雷射光束入射後，該光柵會利用光的 繞射現象產生兩道正負一階繞射光，並將兩道正負一階繞射 光反射至後述之半反射鏡； 一穿透式光柵，於雷射光束入射並穿透過光柵後，該光 栅會利用光的繞射現象產生兩道正負一階繞射光，並將兩道 正負一階繞射光入射至後述之半反射鏡； 二半反射鏡，係接收一階繞射光後，會分光產生一反射 光與一穿透光； 二雷射四象儀，係接收半反射鏡分光射出之穿透光，獲 得的四個位置變化以求解另一組垂直光柵面方向之自由度 位移量與繞三軸旋轉角度之三自由度變化量； 一干涉鏡，係接收半反射鏡分光射出之反射光，使兩道 正負一階反射光疊加形成一干涉光； 透鏡組’係接收並調整干涉鏡射出之干涉光條紋大 8 591199 小’使干涉光條紋與後述之光電二極體陣列的幾何形狀相配 合；以及 - 一光電二極體陣列，係由多個光電二極體組成，能接收 透鏡組輸出之干涉光條紋的訊號相位變化。 【實施方式】 本發明所提供之可量測五自由度訊號系統，主要包括 有· 一雷射二極體1( Laser Diode )、一反射鏡2、一光柵3 (Diffraction Grating)、二半反射鏡 4 (Half Mirror)、 一雷射四象儀 5 (2D PSD)、一干涉鏡 6 (Beam Splitter)、 一透鏡組7 (Lens)以及一光電二極體陣列8 (Photodiode Array ) 〇 為更詳盡說明本發明「請參閱圖一、圖二以及圖三」為 本發明可測量五自由度訊號系統之示意圖以及流程圖，本發 明係主要利用一雷射二極體1入射雷射光束至反射鏡2後再 反射至一設置於光柵3上，並以反射式光柵31或穿透式光 拇32作為感應與訊號轉換傳輸元件，當雷射光束通過光柵3 會產生繞射現象，繞射光為0階，+1、-1階，+2、-2階， + 3、—3階......依此命名，使光源強度迅速減弱，其後將光栅 _ 3固定在平台9上，使雷射光束垂直入射至光柵3產生兩道 正負一階繞射光，並將兩道正負一階繞射光入射至二半反射 鏡4 ’隨著平台9移動及轉動，半反射鏡4接收一階繞射光 後，會分光產生一反射光與一穿透光，分光射出之兩道正負 一階穿透光會各自會進入一雷射四象儀5内，使二組雷射四 象儀5能獲得四個位置變化以求解另一組垂直光柵3面方向 之自由度位移量與繞三軸旋轉角度三自由度變化量；而分光 射出之兩道正負一階反射光會進入一干涉鏡6内，於干涉鏡 9 6_内兩道正負—階反射光會疊加形成-·干涉光條紋後，再由 透鏡、、且7接收並5周整干涉光條紋大小，使輸出之干涉光條 、、/、光電—極體陣列8的幾何形狀相配合，進—步使光電二 極體陣列8接收正負—階干涉光條紋之變化，以進—步獲得 移動平口 1G移動方向位移量，然本裝置之光柵3係設置於 移動平台10上’以提供光柵3之移動位移外，該雷射二極 體1、反射鏡2、半反射鏡4、雷射四象儀5、干涉鏡6、透 鏡組7以及光電二極體陣列8，係共同設置於一平台9上。 虽光電一極體陣列8輸出的干涉光條紋訊號為光強度變 :匕訊號，1¾是會著純3 #動轉動而週期變化的一餘弦訊 號，其光強度振幅受光柵3位移的調制，當平台9移動或轉 動時，光栅3移動或轉動速度的改變，訊號頻率亦隨之變化。 因此，當平台9靜止時，訊號輸出只是與光柵3瞬間位置有 關的直流值，且訊號頻率為零，由於此量測系統對位移量測 要求須達到奈米等級之辨別率，因此可將所得的兩組正交的 弦波汛號利用各種方式而達成的細分割量測系統。 本發明之雷射二極體1另可使用單頻雷射光、雙頻雷射 光或線性調頻半導體雷射光作為一光源，係採用正一階繞射 光與負一階繞射光做為量測依據，經反射鏡2反射至光栅3 繞射後’具有等值、反向雙重都卜勒（Doppler)頻移的正 一階繞射光及負一階繞射光，該兩束光分別經二組半反射鏡 4分光’或也可採用任一具有反射率與穿透率之偏光鏡，以 產生兩組反射光與穿透光，第一個反射光及第二個反射光經 干涉鏡6後疊加形成”干涉光”，亦得到相應隨都卜勒 (Dopp 1 er )頻移大小變化的信號的相移變化，量測基準也 由波長變為光柵常數，當干涉光條紋訊號進入檢測器前，為 使檢測器輪出端能得到一組彼此正交的弦波訊號，系統中利 用一透鏡組7來調整干涉光條紋大小，使其與光電二極體陣 列8的幾何形狀相配合，透過光電二極體陣列8接收訊號的 相位變化，便可以實現對光柵3位移的量測，然光電二極體 陣列8，係由多個光電二極體所組成，該光電二極體是操作 在逆向偏壓之一極體，當光照射在此二極體受光區時會產生 電子-電洞對，致使外電路上能產生電流，於光電二極體陣 列8部分也可從移動方向獲得一組平移自由度位移量。 其-人，將兩組半反射鏡4分光後的正一階穿透光與負一 階穿透光，該正一階穿透光由第一個雷射四象儀5接收產生 以第個位置變化，同樣的負一階穿透光由第二個雷射四象 儀5接收以產生第二個位置變化，然而因光柵3移動方向的 偏擺會改變繞射光束方向，因此藉由兩組穿透光入射至雷射 四象儀5的位置變化可進一步獲得一組垂直光柵3面方向之 自由度位移量與繞三軸旋轉角度之三自由度變化量。 【特點及功效】 本發明所提供之可量測五自由度訊號系統，與前述引證 案及其他習用技術相互比較時，更具有下列之優點： 1 ·使用光波具有高度的指向性與同調性的雷射二極體 當光源，於雷射光束入射光栅時，當光柵有所變動時，繞射 光會隨之產生都卜勒頻移，繞射光栅的都卜勒頻移與光栅的 移動速度及繞射階數成正比、並與光柵常數成反比，而與入 射光的波長及入射方向無關，減少了檢測時的影響因素。 2.當光源入射干涉鏡時，會產生穿透光及反射光，其光 強度可在製造時分別選擇光強度比例，本裝置依據干涉儀的 結構由兩入射光有干涉現象，使其在某些位置上，可產生極 591199 大值與極小值。 3.本發明之干涉鏡可與透鏡組以及光電二極體陣列搭配 使訊號的相位變化’以實現對光柵位移的量測，和獲得I組 平移自由度位移量，對於精密運動平台之精度正提供莫大助 益。 、 綜上所述，本案不但在技術思想上確屬創新，並能較習 用物品增進上述多項功效，應已充分符合新穎性及進步性之 法定發明專利要件，爰依法提出申請，懇請貴局核准本件 發明專利申請案，以勵發明，至感德便。 【圖式簡單說明】 睛參閱以下有關本發明一較佳實施例之詳細說明及其附 圖’將可進一步瞭解本發明之技術内容及其目的功效；有關 該實施例之附圖為： 圖一為本發明可量測五自由度訊號系統之反射式光柵量 測系統之示意圖； 圖二為該可測量五自由度訊號系統之穿透式光栅量測系 統之示意圖；以及 圖三為該可量測五自由度訊號系統之流程圖。 【主要部分代表符號】 1雷射二極體 2反射鏡 3光柵 31反射式光柵 32穿透式光栅 4半反射鏡 5雷射四象儀 12 6干涉鏡 7透鏡組 8光電二極體陣列 9平台 10移動平台 13—1. Γ sigh is a narrow product. Therefore, when measuring all errors, different measurement architectures need to be replaced. The alignment of the instrument's installation reference axis also needs to be individually calibrated. The actual measurement path measured every time is not re-calibrated.次 路 # is exactly the same. Multiple corrections also cause errors. ^ Measurement is time-consuming and increases measurement uncertainty. The automatic collimation instrument _ degree ^ has a high resolution, but the overall structure is too heavy to fit on the machine. Measurement. The development of optical rulers combines the principles of grating diffraction and interference in recent years. The cutting technology and the development of two-dimensional grating technology have been developed. At present, optical rulers, such as Zhong 6 591199 Republic of China invention patent certificate number: 99283, patent name: right Grating defects and diffraction grating linear optical rulers with high tolerance for misalignment. Among them, two-dimensional positioning can be provided and the resolution can reach nanometer level. Although two-dimensional optical rulers are easy to set up, they can only be used with high resolution. Provides two-dimensional signals, which cannot provide simultaneous multi-degree-of-freedom errors for precision motion positioning; if the measurement system can only detect one or two errors at a time, then all errors must be measured. The longer it takes, the environment Changes are also getting harder to measure, and measurement uncertainty will increase over time. Therefore, on measuring instruments that detect linear platforms and X and γ motion platforms, no matter whether the measuring instruments are laser interferometers, optical rulers, automatic collimators, or electronic water level translation, you can only measure one or two at a time. It is impossible to measure five degrees of freedom errors at the same time, which makes the measurement more inefficient. It can be seen that there are still many shortcomings in the above-mentioned conventional articles, and they are not a good designer. They need to be improved. In view of the various shortcomings derived from the above-mentioned conventional optical ruler combining grating diffraction and interference principle and electronic segmentation technology, the inventor of this case has been eager to improve and innovate. After years of painstaking and meticulous research, he finally successfully developed this measurable DOF signal system. [Objective of the Invention] _ The purpose of this month is to provide a measurable five-degree-of-freedom signal system. The laser diode has the same directivity and coherence as the general laser, but But it is more able to achieve a smaller volume and greater efficiency. A second object of the present invention is to provide a measurable five-degree-of-freedom signal system, in which the half-mirror generates transmitted light and reflected light when positive and negative first-order diffracted light is incident, and transmitted light and reflected light The intensity is only half of the intensity of the incident light. 7 591199 Another object of the present invention is to provide a measurable five-degree-of-freedom signal system, in which the interferometer can superimpose two positive and negative first-order reflected lights to form an interference light. Dopp 1 er) The phase shift signal changes with the frequency shift magnitude. Another object of the present invention is to provide a measurable five-degree-of-freedom signal system, in which the lens group is composed of a plurality of lenses, thereby adjusting the size of the interference fringes to make the geometry of the photodiode array Cooperate. [Content] A measurable five-degree-of-freedom signal system that can achieve the above-mentioned object of the invention includes: a laser and a polar body, where k is used for the laser beam to be incident on a mirror described later; a mirror is used to receive the laser beam Reflected to the later-mentioned grating; a reflective grating, after the laser beam is incident, the grating will use the diffraction phenomenon of light to generate two positive and negative first-order diffraction lights, and reflect the two positive and negative first-order diffraction lights to the latter half Reflector; a transmissive grating, after the laser beam is incident and passes through the grating, the grating will use the diffraction phenomenon of light to generate two positive and negative first-order diffracted lights, and enter two positive and negative first-order diffracted lights into the later described Two half mirrors; two half mirrors, after receiving the first-order diffracted light, will split the light to produce a reflected light and a penetrating light; two laser four imagers, which receive the penetrating light emitted by the half mirror reflection The four position changes of the two are used to solve another set of degrees of freedom displacement in the direction of the vertical grating plane and three degrees of freedom change in the rotation angle around the three axes; an interferometer is used to receive the reflected light emitted by the half-mirror light, so that two The positive and negative first-order reflected light are superimposed to form an interference light; the lens group 'receives and adjusts the interference light fringe emitted by the interference mirror to be large 8 591199 small' so that the interference light fringe matches the geometry of the photodiode array described later; and- A photodiode array is composed of multiple photodiodes and can receive the phase change of the signal of the interference light fringe output by the lens group. [Embodiment] The measurable five-degree-of-freedom signal system provided by the present invention mainly includes a laser diode 1 (laser diode), a mirror 2, a grating 3 (Diffraction Grating), and two semi-reflections Mirror 4 (Half Mirror), a laser four imager 5 (2D PSD), an interferometer 6 (Beam Splitter), a lens group 7 (Lens), and a photodiode array 8 (Photodiode Array). Detailed description of the present invention "Please refer to Fig. 1, Fig. 2 and Fig. 3" is a schematic diagram and flowchart of a five-degree-of-freedom signal system of the present invention. The present invention mainly uses a laser diode 1 to incident a laser beam to the reflection Mirror 2 is then reflected on a grating 3, and a reflective grating 31 or a transmissive optical thumb 32 is used as the induction and signal conversion and transmission element. When the laser beam passes through the grating 3, a diffraction phenomenon occurs. The diffracted light is Order 0, +1, -1, +2, -2, +3, -3 ... Named after this, the intensity of the light source is quickly weakened, and then the grating _ 3 is fixed on the platform 9 , Make the laser beam perpendicular to the grating 3 to generate two positive and negative first-order diffracted lights, and The negative first-order diffracted light is incident on the second half mirror 4 ′ As the platform 9 moves and rotates, after receiving the first-order diffracted light, the half-mirror 4 will split the light into a reflected light and a penetrating light. The first-order penetrating light will enter each of the four laser imagers 5, so that two sets of laser four imagers 5 can obtain four position changes to solve another group of vertical gratings in three directions of freedom. Three-axis rotation angle with three degrees of freedom change; and the two positive and negative first-order reflected lights emitted by the beam splitter will enter an interferometer 6 and two positive and negative within the interferometer 9 6_—the order reflected light will be superimposed to form the interference light After the streaks are received by the lens, and 7 and the interference light fringe size is adjusted for 5 weeks, the geometric shapes of the output interference light bars and / or the opto-electrode array 8 are matched to further make the photodiode The array 8 receives the change of the positive-negative-order interference light fringe to further obtain the displacement amount of the moving flat port 1G in the moving direction. However, the grating 3 of the device is provided on the mobile platform 10 'to provide the displacement of the grating 3. Emitter diode 1, mirror 2, half mirror 4 The four laser imagers 5, the interferometer 6, the lens group 7, and the photodiode array 8 are all arranged on a platform 9. Although the interference light fringe signal output by the photoelectric monopole array 8 is a light intensity change: Dagger signal, 1¾ is a cosine signal that will rotate with a pure 3 # and rotate periodically. Its light intensity amplitude is modulated by the displacement of the grating 3, when When the platform 9 moves or rotates, the movement or rotation speed of the grating 3 changes, and the signal frequency changes accordingly. Therefore, when the platform 9 is stationary, the signal output is only a DC value related to the instantaneous position of the grating 3, and the signal frequency is zero. Since this measurement system requires a nanometer level discrimination rate for displacement measurement, the obtained The two sets of orthogonal sine wave flood numbers use various methods to achieve a fine division measurement system. The laser diode 1 of the present invention can also use a single-frequency laser light, a dual-frequency laser light, or a chirped semiconductor laser light as a light source, and uses positive first-order diffraction light and negative first-order diffraction light as a measurement basis. Reflected by the mirror 2 to the grating 3 and diffracted, the positive first-order diffracted light and the negative first-order diffracted light having the equivalent, reverse double Doppler frequency shift, and the two beams are respectively reflected by two groups of semi-reflections Mirror 4 beam splitting 'or any polarizer with reflectivity and transmittance can be used to generate two sets of reflected light and transmitted light. The first reflected light and the second reflected light are formed by superposing the interference mirror 6 “Interfering light” also obtains the phase shift of the corresponding signal that changes with the Dopp 1 er frequency shift. The measurement reference also changes from the wavelength to the grating constant. When the interference light fringe signal enters the detector, it is A set of orthogonal sine wave signals can be obtained at the output end of the detector wheel. A lens group 7 is used in the system to adjust the interference light fringe size to match the geometry of the photodiode array 8. Phase change of signal received by polar array 8 The displacement of the grating 3 can be measured. However, the photodiode array 8 is composed of a plurality of photodiodes. The photodiode is one of the poles operated under reverse bias. When light is irradiated on the Electron-hole pairs are generated in the light-receiving area of this diode, so that an electric current can be generated in the external circuit. A set of translational degrees of freedom displacement can also be obtained from the moving direction in the 8-diode array. It is a person, after splitting the two sets of half-mirrors, the positive first-order transmitted light and the negative first-order transmitted light are received. The positive first-order transmitted light is received by the first laser four-imager 5 to generate the first Position change, the same negative first-order penetrating light is received by the second laser imager 5 to generate a second position change. However, the deviation of the movement direction of the grating 3 will change the direction of the diffracted beam. The position change of the group of penetrating light incident on the four laser imager 5 can further obtain a group of three degrees of freedom displacement of the vertical grating 3 plane direction and three degrees of freedom of rotation angle about three axes. [Features and effects] The five-degree-of-freedom signal system provided by the present invention has the following advantages when compared with the aforementioned citations and other conventional technologies: 1 · The use of light waves has a high degree of directivity and coherence. When the laser diode is the light source and the laser beam enters the grating, when the grating is changed, the Doppler frequency shift will occur along with the diffracted light. The Doppler frequency of the diffraction grating and the moving speed of the grating and The diffraction order is proportional to and inversely proportional to the grating constant, and has nothing to do with the wavelength and direction of incident light, which reduces the influencing factors during detection. 2. When the light source enters the interferometer, the penetrating light and the reflected light will be generated. The light intensity can be selected separately during the manufacturing process. According to the structure of the interferometer, this device interferes with the two incident light, which makes it in a certain position. At these positions, extreme values of 591199 and minimum values can be generated. 3. The interferometer of the present invention can be used with the lens group and the photodiode array to change the phase of the signal to achieve the measurement of the grating displacement and obtain the displacement of the group I translational freedom degree. The accuracy of the precision motion platform is positive. Provide great benefits. To sum up, this case is not only technically innovative, but also enhances the above-mentioned multiple effects compared with conventional items. It should have fully met the requirements for statutory invention patents that are novel and progressive. Apply for it in accordance with the law and ask your office for approval. This invention patent application is designed to encourage inventions, to the utmost convenience. [Brief description of the drawings] Please refer to the following detailed description of a preferred embodiment of the present invention and the accompanying drawings' for further understanding of the technical content of the present invention and its purpose and effect; the drawings related to this embodiment are: Figure 1 It is a schematic diagram of a reflective grating measuring system capable of measuring a five-degree-of-freedom signal system according to the present invention; FIG. 2 is a schematic diagram of a penetrating grating measuring system capable of measuring a five-degree-of-freedom signal system; Flow chart of a five-degree-of-freedom signal system. [Representative symbols of main parts] 1 Laser diode 2 Reflector 3 Grating 31 Reflective grating 32 Penetrating grating 4 Half mirror 5 Laser four imager 12 6 Interferometer 7 Lens group 8 Photodiode array 9 Platform 10 mobile platform 13