200419136 玖、發明說明 (發明說明應敘明：發明所屬之技術領域、先前技術、内容、實施方式及圖式簡單說明） 【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 一種利用光栅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】 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&，~，心與三個角位移俯仰、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 至六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。 若以HP干涉儀而言，其一次只能量取一項幾何誤差， 因此在量測所有誤差時需更換不同量測架構，儀器的安裝和 參考軸的對準亦需個別校正，每次重新校正所量取的實際量 測路徑並無法與前次路徑完全相同，多次校正亦產生誤差， 量測耗時而且增加量測不確定性，而自動視準儀器對轉動角 度雖具有高解析度，但整體架構太重不適合安裝機器上做線 上量測。 光學尺的發展上近年來結合光柵繞射與干涉原理、電子 分割技術與二維光栅製造的技術發展，目前已有光學尺，如中 200419136 華民國發明專利證號：99283,專利名稱：對光柵缺陷與對 位不準具有高容許度之繞射光栅線性光學尺，其中，可提供 一維疋位且解析度可達奈米級，雖然二維光學尺架設容易解 析度咼，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、Y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 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 设计者’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】 本發明之目的即在於提供一種可量測五自由度訊號系 、、先，其中δ亥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 唬系統，其中該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。 200419136 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，因而得到相應隨之都卜勒（D〇ppler)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，使其與光電二極體單元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： 一雷射二極體，係提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； 一反射式光柵，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栅後，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； 一透鏡組，係接收並調整干涉鏡射出之干涉光條紋大 200419136 小，使干涉光條紋與後述之光電二極體單元的幾何形狀相配 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)、 二雷射四象儀 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(ph〇t〇di〇de Array ) 〇 為更詳盡說明本發明「請參閱圖一、圖二」為本發明可 測量五自由度訊號系統之示意圖，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，並以反射式光栅31或穿透式光柵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，其後將光柵3固定在平台g上， 使雷射光束垂直入射至光拇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g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6内兩道正負一階反 200419136 干涉光後，再由 射光會疊加形成 ,，〜丨-可問一逍鏡組7接收並编黎不 涉光條紋大小’使輸出之干涉光條紋與光電二極體單㈣ 何形狀相配合，進一步使光雷-& μ。 7尤电—極體陣列8接收正負一階干 涉光條紋之變化，以進一步獲得移動 + 旦紅丄4 又初卞口 1 〇移動方向位移 篁，然本裝置之光柵3係設置於移動平台1〇上，以提供光 柵3之移動位移外，該雷射二極體卜反射鏡2、半反射鏡、4、 雷射四象儀5、干涉鏡6、透鏡組7以及光電二極體陣兄列， 係共同設置於一平台9上。 當光感應器輸出的干涉光條紋訊號為光強度變化訊號， 隨是會著光柵3移動轉動而週期變化的一餘弦訊號，其^強 度振幅受光柵3位移的調制，當平台9移動或轉動時，光柵 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，訊號輸出只是與光栅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訊號 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反設至光栅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 200419136 使檢測器輸出端能得到一組彼此正交的弦波訊號，系統中利 用透鏡组7來調整干涉光條紋大小，使其與光電二極體單 元的幾何形狀相配合，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 逆向偏壓之二極體，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。 其次，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H透光由第—個雷射四象儀5接收產生 以第一個位置變化，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-步獲得-組垂直光柵3面方向之 自由度位移里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 、田光源力雷射光束入射光拇日寺，當光拇有所變動時，繞射 光會Ik之產生都卜勒頻移，繞射光栅的都卜勒頻移與光拇的 移動速度及繞射階數成正比、並與光栅常數成反比，而與入 射光的波長及入射方 丁万向無關，減少了檢測時的影響因辛。 2·當光源入射千、牛於# 尺七 对干涉鏡時’會產生穿透光及反射光，1 = = :刀別選擇光強度比例，本裝置依據干涉儀的 結構由兩入射光有+、牛 頁干V現象，使其在某些位置上，可產生極 200419136 大值與極小值。 /·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，和獲得一組 平移自由度位移量，對於精密運動平纟之精度JL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 法疋發明專利要件，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】 · 請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栅量 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 圖二為該可量測五自由度訊號糸統之k私圖 【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穿透式光柵 4半反射鏡 5雷射四象儀 12 200419136 6干涉鏡 7透鏡組 8光電二極體陣列 9平台 1 0移動平台200419136 发明 Description of the invention (The description of the invention should state: the technical field to which the invention belongs, the prior art, the content, the embodiments, and the drawings) [Technical field to which the invention belongs] The present invention relates to a measurable five-degree-of-freedom signal A system, particularly a measurable five-degree-of-freedom signal system established using the principle of grating diffraction and optical interference. [Previous technology] General precision platform movement is a multi-degree-of-freedom azimuth change and affects each target to produce errors. In actual movement, a six-degree-of-freedom error will be generated, including three linear displacement errors & , Sway, rolling error, because the motion platform is designed and assembled through linear components, rotating platforms and other components to have multiple degrees of freedom, the characteristics of various motion platforms in the machine will affect the accuracy of the entire machine and the quality of processed products, The positioning of the workpiece to be processed, the installation of precision parts, and the position and attitude of the target object in the space require measurement and adjustment or control of up to six degrees of freedom; therefore, higher requirements for multi-degree-of-freedom detection are required. What is lacking is the ability to measure multiple degrees of freedom of a workpiece, component or target object in space simultaneously. In the case of the HP interferometer, only one geometric error can be measured at a time. Therefore, when measuring all errors, different measurement structures need to be replaced. The installation of the instrument and the alignment of the reference axis also need to be individually calibrated, and recalibrated each time. The actual measurement path measured cannot be exactly the same as the previous path. Multiple corrections also cause errors. The measurement is time-consuming and increases the measurement uncertainty. Although the automatic collimation instrument has a high resolution for the rotation angle, However, the overall structure is too heavy for online measurement on the installation machine. The development of the optical ruler combines the principles of grating diffraction and interference, electronic segmentation technology and the development of two-dimensional grating technology in recent years. Currently, there are optical rulers, such as China 200419136 Republic of China invention patent certificate number: 99283, patent name: pair of gratings Defects and misalignment linear diffraction ruler with high tolerance of diffraction grating. Among them, one-dimensional chirp can be provided and the resolution can reach nanometer level. Although two-dimensional optical ruler is easy to set up, it can only provide resolution. Two-dimensional signals 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, all errors must be measured. The longer it takes, the environment changes. It is also increasingly difficult to measure, and measurement uncertainty will increase over time. Therefore, on measuring instruments for detecting linear platforms and X and Y motion platforms, no matter whether the measuring instruments are laser interferometers, optical rulers, automatic collimators, or electronic horizontal shifts, only one or two can be measured at a time. Degree of freedom error, but can not measure five degrees of freedom error at the same time, making the measurement work more inefficient. It can be seen that there are still many shortcomings in the above-mentioned conventional articles, which are not a good designer 'and 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 the present invention is to provide a signal system capable of measuring five degrees of freedom. First, the δHai laser diode has the same directivity and coherence as ordinary lasers. 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 bluffing system, in which the semi-reflector generates transmitted light and reflected light when positive and negative first-order diffraction light is incident, and the transmitted light and reflected light The light intensity is only half the intensity of the incident light. 200419136 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, so as to obtain the corresponding Doppler (D0). ppler) A phase shift signal whose frequency shift varies. Another object of the present invention is to provide a measurable five-degree-of-freedom signal system, in which a lens group is formed by combining a plurality of lenses, thereby adjusting the size of the interference fringe to make the geometry of the photodiode unit Cooperate. [Content] A measurable five-degree-of-freedom signal system that can achieve the above-mentioned invention objectives includes: a laser diode that provides a laser beam to be incident on a mirror described later; a mirror that receives the reflection of a laser beam To the grating described later; 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 later-mentioned semi-reflection Mirror; a penetrating 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 Half mirror; two half mirrors, which receive 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 Four position changes to solve another set of degrees of freedom displacement in the direction of the vertical grating plane and three degrees of freedom change in rotation angle around three axes; an interferometer, which receives the reflected light emitted by the half mirror, and The positive and negative first-order reflected light of the channel are superimposed to form an interference light; a lens group is used to receive and adjust the interference light fringe emitted by the interference mirror to be larger than 200419136, so that the interference light fringe matches the geometry of the photodiode unit 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), two laser four imagers 5 (2D PSD), an interferometer 6 (Beam Splitter), a lens group 7 (Lens), and a photodiode array 8 (ph〇t〇di〇 de Array) 〇 For a more detailed explanation of the present invention "see Figures 1 and 2" is a schematic diagram of a five-degree-of-freedom signal system of the present invention. The present invention mainly uses a laser diode 1 to incident the laser beam to the reflection Mirror 2 is then reflected on a grating 3, and a reflective grating 31 or a transmissive grating 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, and the diffracted light is 0. Order, +1 order, -1 order, +2 order, -2 order, +3 order, -3 order ... named 'make the light source intensity rapidly weaken, and then fix the grating 3 on the platform g, Make the laser beam perpendicularly incident on the thumb 3 to generate two positive and negative first-order diffracted lights, and make two positive and negative first-order diffracted lights incident To the second half mirror 4, as the platform g moves and rotates, after the half mirror 4 receives the first-order diffracted light, it will split the light to produce a reflected light and a penetrating light. Each will enter a laser four-imager 5 so that two groups of laser four-imager 5 can obtain four position changes to solve another group of vertical gratings with three degrees of freedom displacement and three rotation angles around three axes The two positive and negative first-order reflected lights emitted by the beam splitter will enter an interference mirror 6, and after the two positive and negative first-order anti-200419136 interference lights in the interference mirror 6, the incident light will be superimposed to form, ~ 丨- May ask a small mirror group 7 to receive and edit the size of the fringe-independent light fringe to make the interference light fringe of the output match the shape of the photodiode unit, and further make the light thunder-amp. 7 You Dian—the polar array 8 receives the positive and negative first-order interference light fringe changes to further obtain the movement + denier 4 and the initial opening 1 〇 displacement in the moving direction 篁, but the grating 3 of this device is set on the mobile platform 1 〇, in order to provide the movement displacement of the grating 3, the laser diode mirror 2, half mirror, 4, laser four imager 5, interferometer 6, lens group 7, and photodiode array brother The columns are arranged on a platform 9 in common. When the interference light fringe signal output by the optical sensor is a light intensity change signal, it is a cosine signal that changes periodically with the movement of the grating 3. The amplitude of its intensity is modulated by the displacement of the grating 3. When the platform 9 moves or rotates When the speed of the grating 3 moves or rotates, 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 signals 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. After being inverted by the mirror 2 and diffracted by the grating 3, the positive first-order diffracted light and the negative first-order diffracted light having an equivalent and reverse double Doppler frequency shift are respectively transmitted through two groups. The half mirror 4 splits the light, 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 pass through the interference mirror 6. The "interference light" is superimposed, and the phase shift of the signal corresponding to the Doppler frequency shift is also obtained. The measurement reference also changes from the wavelength to the grating constant. When the interference light fringe signal enters the detector, To make a set of orthogonal sine wave signals at the output end of the detector for 200419136, the lens group 7 is used in the system to adjust the size of the interference light fringe to match the geometry of the photodiode unit. Phase of polar body array 8 receiving signal The change can be achieved to measure the displacement of the grating 3. However, the photodiode array 8 is composed of a plurality of photodiodes. The photodiodes are diodes that operate under reverse bias. Electron hole pairs will be generated when the light-receiving area of the diode is irradiated, so that an electric current can be generated in the external circuit. A group of translational freedom displacements can also be obtained from the moving direction in the 8-diode array. Secondly, the positive first-order transmitted light and the negative first-order transmitted light after the two sets of half-mirrors are split by four, and the positive H transmission is received by the first laser four-imager 5 to change at the first position. The same negative first-order transmitted light is received by the second laser imager 5 to generate a second position change. However, the deflection of the moving direction of the grating 3 will change the direction of the diffracted beam, so it is transmitted through two groups. The change in the position of light incident on the four laser imager 5 can be further obtained-the three degrees of freedom change in the three degrees of freedom displacement of the three vertical directions of the group of vertical gratings. [Features and effects] The five-degree-of-freedom measurement signal system provided by the present invention has the following advantages when compared with the aforementioned citations and other conventional techniques. · 1 · The use of light waves has a high degree of directivity and coherence. Laser diodes and Tian Guangyuan force laser beams are incident on the light thumb temple. When the light thumb is changed, the diffracted light will produce Ib Doppler frequency shift, and the Doppler frequency shift of the diffraction grating and light The moving speed of the thumb and the diffraction order are directly proportional to each other, and inversely proportional to the grating constant, and have nothing to do with the wavelength of the incident light and the direction of the incident square, which reduces the influence of the detection. 2 · When the light source enters the Qian and Niu ## 7 pair of interferometers, it will produce penetrating light and reflected light. 1 = =: The light intensity ratio is selected by the knife. According to the structure of the interferometer, the two incident lights have + The V-shaped phenomenon of Niu page dry causes it to produce extreme values of 200419136 and minimum values at certain positions. / · The interferometer of the present invention can be matched with a lens group and a photodiode array to change the phase of the signal to realize the measurement of the grating displacement, and obtain a set of translational degrees of freedom. JL can help. 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 novelty and progressive law (invention patent requirements), and applied in accordance with the law. Please 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: One 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. Two is a schematic diagram of a penetrating grating measuring system capable of measuring a five-degree-of-freedom signal system; and FIG. Measure the private image of the signal system of five degrees of freedom [main part representative symbols] 1 laser diode 2 reflector 3 grating 31 reflective grating 32 penetrating grating 4 half mirror 5 laser four imager 12 200419136 6 Interferometer 7 Lens Group 8 Photodiode Array 9 Platform 1 0 Mobile Platform