1250269 【發明所屬之技術領域】 本發明係有關一種表面電漿波微小角度之測量方法，尤指一種 利用表面電漿波共振對光產生極大相位或強度變化特性，使光導向 可產生表面電漿波之棱鏡，經反射後所測得之相位差或反射率，而 求得待測物之微小旋轉角度或位移量者。 【先前技術】 按表面電漿共振技術（surface plasmon resonance ; S/死）在 近幾十年來受到國内外研究之矚目，尤其在近年來在微小角度量測 方面，Chiu及Su [1,2]曾發表過以全反射時引入的相位差測量稜 鏡的旋轉角度（參考文獻：Μ· H· Chiu, and D. C. Su /‘Angle measurement using total-intemal-reflection heterodyne interferometry,9, Opt· Eng· 36(6)，1750-1753, 1997。及 Μ· H· Chiu· and D· C. Su， “Improved technique for measuring small angles，' Appl. Opt· 36, 7104-7106,1997)，後來Chiu [3]以相同的方法（參考文獻：Μ·Η· Chiu，S· F· Wang，and R· S· Chang，“Instrument for measuring small angles by use of multiple total internal reflections in heterodyne interferometry”，Appl. Opt. 43, NO· 29, 5438-5442, 2004)，將稜鏡改 良為長條型^稜鏡架構其最高的解析度可達2x10'adian量測範圍 為-2.124K2.12。。另外Huang [4-6]等人曾發表以臨界角時P偏極 光之強烈光強度變化作為微小角度量測其解析度亦可達到〇· 〇4” (參考文獻：P· S· Huang，S· Kiyono，and 0· Kamada，“Angle measurement based on the internal reflection effect : a new 1250269 method”，Appl. Opt· 31，6047-6055，1992。R S· Huang and J· Ni， “Angle measurement based on the internal reflection effect and the use of right- angle prisms”，Appl· Opt· 34, 4976_4981，1995。P· S· Huang and J· Ni，“Angle measurement based on the internal-reflection effect using elongated critical prisms'Appl· Opt· 35, 2239-2241，1996) 〇 本發明不同於以上的方法，其乃利用表面電漿共振原理結合共 光程外差干涉儀高精確穩定的優點，可以測出在共振角附近之相位 與強度的變化，及量出水平(P)與垂直(S)偏極光之間的相位差以及 干涉的對比度，而換算出入射光的角度，當此相位差或光強度改變 時，即可知其旋轉的方向與旋轉角度的大小。 【發明内容】 本發明之主要目的在於提供一種具有較高的檢測精確度及靈 敏度’並可以測出待測物在共振角附近之相位與強度的變化，及換 算出入射光的角度旋轉的方向與旋轉角度的大小或微小位移量的 測量方法，其係建立相位差或反射率之比對參數值資料庫，並採用 一可產生表面電漿共振效果之稜鏡，該稜鏡反射邊設有至少一層金 屬膜，並將待測物置於與該稜鏡同步轉動的位置上，並以外差光源 或線性偏極雷射光源經分光鏡而分為反射光與透射光，以該反射光 為參考光，而該透射光為測試光，其中，測試光導向該稜鏡，並使 入射至該稜鏡斜邊的入射角在表面電漿共振角的附近，利用光偵 測器測得該參考信號，並利用光偵測器測得該測試光之第一 測試信號，待測物連同稜鏡做小角度旋轉時，產生第二參考信號 1250269 及第二測試信號，细第-、第二參考信號及第_、第二測試信 號，透過電腦的計算及與所建立的該她差献射率崎參數值^ 料庫做比對，進而換算出該稜鏡與該待測物旋轉方向與旋轉的角 度。 本發明之另-主要目的在於提供一種具有較高的檢測精確度 及靈敏度，並可以測出待測物在共振角附近之相位與強度的變化， 及換算出入射光的角度旋轉的方向與旋轉角度的大小的表面電漿 波微小角度測量方法的系統，其係包括可產生電漿共振效果之稜鏡 之反射邊設有至少一層的金屬膜，可使光源裝置的光源反射與透射 之分光鏡，至少一個用以偵測光射之光偵測器及可將來自光偵測器 之訊號予以處理及運算而求得相關數值的電腦。 【實施方式】 請配合參看第一至七圖所示，本發明較佳實施例之量測方法實 施時，其包括： 建立相位差或反射率之比對參數值資料庫； 採用一可產生表面電漿共振效果之稜鏡(1〇)，該稜鏡(1〇)反射 邊設有至少一層金屬膜(11)，並將待測物置於可與該稜鏡(10)同步 轉動的位置上； 以外差光源(21)或線性偏極雷射光源(22)經分光鏡(30)而分為 反射光與透射光，以該反射光為參考光，而該透射光為測試光，其 中，測試光導向該棱鏡(10)，並使入射至該棱鏡(10)斜邊的入射角 在表面電漿共振角的附近； 1250269 利用光偵測器（40)測得該參考光之第一參考相位信號或 第一參考光強度信號； 並利用光福測器（40)測得該測試光之第一測試相位信號 或第一測試光強度信號； 當待測物連同稜鏡(10)做小角度旋轉時，會產生第二參考相位 信號或第二參考光強度信號，及第二測試相位信號或第二測試 光強度信號；及 利用第一、第二參考相位信號及第一、第二測試相位信號或第 一、第二參考光強度信號及第一、第二測試光強度信號，透過電腦 (50)的計算及與所建立的該相位差或反射率比對參數值資料庫做比 對，進而換算出該稜鏡(10)與該待測物旋轉方向與旋轉的角度者。 請參看第五圖所示，本發明較佳例實施時，其中，若所建立的 是相位差之比對參數值資料庫，則採用的光源為外差光源(21),而 在光偵測器(40)之前先使參考光及測試光經檢偏板，而在光偵測器 之後則以相位比較器(60)取得其相位信號，再輸入電腦(5〇)計算。 凊參看第六圖所示，本發明較佳例實施時，其中，若所建立的 是反射率之比對參數值資料庫，則採用的光源為線性偏極雷射光 (22)，直接以光偵測器(4〇)測得參考光及測試光之信號，再輸入電 腦(50)計算。 請參看第七圖所示，本發明較佳例實施時，其中，利用所測得 之稜鏡(ίο)旋轉角度，再將光源經物鏡(70)入射平面反射鏡(71)而反 1250269 射回原路徑’利用該平面鏡συ未能在該物鏡(70)之焦平面時造成 反射光有收斂或發散的現象，再利用此發散或收斂光入射該稜鏡 (10)位於表面電漿共振角附近時引起不同之相位差值，再由該相位 差值比對原先測得之旋轉角度而求得該待測物平面的微小位移量。 請參看第一至第七圖所示，本發明較佳例實施時，包括有： 一可產生電漿共振效果之稜鏡(10)，該稜鏡(10)反射邊設有至少 一層金屬膜(11)，其中，該金屬膜(11)的材質可為金； 一光源裝置(20); 一可使光源反射與透射之分光鏡(3〇); 至少一個用以偵測光射之光偵測器(4〇);及 一可將來自光偵測器(40)之訊號予以處理及運算而求得相關數值 的電腦(50)。 請參看第一圖所示，本發明較佳例實施時，其中，該稜鏡(1〇) 反射邊設有二層異質之金屬膜(11)。 請參看第一圖所示，本發明較佳例實施時，其中，該稜鏡(1〇) 反射邊設有三層異質之金屬膜(12)。 請參看幕五、六圖所示，本發明較佳例實施時，其中，該稜鏡 (10)設於一旋轉台(13)上。 請參看第五圖所示’本發明較佳例實施時，其中，該光源裝置 (20)為外差光源(21) ’並在光偵測器(40)前設有檢偏板(80)。 請參看第六圖所示，本發明較佳例實施時，其中，該光源裝置 1250269 (20)為線性偏極光源(22)，並在該光源(22)射出光線之路徑上設一 偏極板(23)。 请參看第八、九圖所示，本發明較佳例實施時，其中，進一步 包括有物鏡(70)與平面反射鏡(71)，使光源經物鏡(7〇)入射該平面反 射鏡(71)而反射回原路徑。 請參看第一至第三圖所示，本發明較佳例於操作實施時，係以 Kretschmaim四層結構為例，第一層為稜鏡(1〇)，折射率為以，第 一層為金屬膜，其折射率為n2,第三層為另一種金屬膜，其折射率 為n3，第四層為空氣，其折射率為η4=：ι·〇，入射光經“ n2n3n4 反射之反射係數為 Γ1234 L 4+‘严〆2 1+«34严〆2 -(2) 為由第-層至二、四層反射的反射係數為第二層的薄膜厚度； 4為第三層的薄膜厚度·〆可代表為S或p偏極，盆中〆五/-< 第i層至第小 層的反射係數，且 E^Jj Yk t = p I = i，j · ·BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for measuring a microscopic angle of a surface plasma wave, and more particularly to a method of utilizing surface plasma wave resonance to generate a great phase or intensity change characteristic of light, and directing light to generate surface plasma. The prism of the wave, the phase difference or reflectance measured after reflection, and the small rotation angle or displacement of the object to be tested is obtained. [Prior Art] Surface plasmon resonance (S/death) has attracted attention from domestic and foreign research in recent decades, especially in recent years in terms of micro-angle measurement, Chiu and Su [1,2] The rotation angle of the phase difference measured by total reflection has been published (Reference: H. Chiu, and DC Su / 'Angle measurement using total-intemal-reflection heterodyne interferometry, 9, Opt· Eng· 36 (6), 1750-1753, 1997. Μ·H· Chiu· and D· C. Su, “Improved technique for measuring small angles,' Appl. Opt· 36, 7104-7106, 1997), later Chiu [3] In the same way (References: Μ·Η·Chiu, S·F· Wang, and R·S· Chang, “Instrument for measuring small angles by use of multiple total internal reflections in heterodyne interferometry”, Appl. Opt. 43, NO· 29, 5438-5442, 2004), the 稜鏡 is improved to a long strip structure, the highest resolution is up to 2x10'adian measurement range is -2.124K2.12. In addition, Huang [4 -6] et al. have published P-polarized light at a critical angle The intensity of the light intensity can be as small as the angle of measurement. The resolution can also reach 〇· 〇4” (Reference: P·S· Huang, S· Kiyono, and 0· Kamada, “Angle measurement based on the internal reflection effect : a New 1250269 method", Appl. Opt. 31, 6047-6055, 1992. RS· Huang and J. Ni, "Angle measurement based on the internal reflection effect and the use of right-angle prisms", Appl· Opt·34, 4976_4981, 1995. P·S· Huang and J. Ni, “Angle measurement based on the internal-reflection effect using elongated critical prisms' Appl· Opt· 35, 2239-2241, 1996) 〇 The present invention differs from the above method in that it utilizes a surface The plasma resonance principle combined with the high accuracy and stability of the common path heterodyne interferometer can measure the phase and intensity changes around the resonance angle, and measure the phase between the horizontal (P) and vertical (S) polarized light. The difference between the difference and the contrast of the interference, and the angle of the incident light is converted. When the phase difference or the light intensity is changed, the direction of the rotation and the angle of the rotation are known. SUMMARY OF THE INVENTION The main object of the present invention is to provide a higher The detection accuracy and sensitivity' can be used to measure the phase and intensity changes of the object under the resonance angle, and to measure the direction of the angular rotation of the incident light and the measurement of the magnitude or the amount of the rotation. The ratio of the phase difference or the reflectance to the parameter value database, and a 可 which produces a surface plasma resonance effect, the 稜鏡 reflection edge is provided with at least a layer of metal film, and placing the object to be tested in a position synchronous with the 稜鏡, and the external difference light source or the linear polarization laser source is divided into reflected light and transmitted light by the beam splitter, and the reflected light is used as reference light And the transmitted light is test light, wherein the test light is directed to the flaw, and the incident angle incident on the skewed edge is near the surface plasma resonance angle, and the reference signal is measured by the photodetector, And using the photodetector to measure the first test signal of the test light, and when the object to be tested rotates with a small angle, the second reference signal 1250269 and the second test signal are generated, and the second and second reference signals are The first and second test signals are compared with the established database by the calculation of the difference, and the angle of rotation and rotation of the object to be tested is converted. Another main object of the present invention is to provide a high detection accuracy and sensitivity, and to measure changes in phase and intensity of the object to be measured near the resonance angle, and to convert the direction and rotation of the angular rotation of the incident light. angle A system for measuring the surface acoustic wave micro-angle of a degree, comprising a metal film with at least one layer of reflective edges capable of generating a plasma resonance effect, and a spectroscope capable of reflecting and transmitting the light source of the light source device At least one photodetector for detecting light and a computer capable of processing and calculating the signal from the photodetector to obtain a correlation value. [Embodiment] Please refer to the first to seventh figures. When the measuring method of the preferred embodiment of the present invention is implemented, the method includes: establishing a phase difference or reflectance ratio parameter value database; using a 稜鏡 (1〇) which can generate a surface plasma resonance effect, the edge The reflecting edge of the mirror (1〇) is provided with at least one metal film (11), and the object to be tested is placed at a position synchronous with the crucible (10); the heterodyne source (21) or the linear polarized laser source (22) divided into reflected light and transmitted light by a beam splitter (30), wherein the reflected light is reference light, and the transmitted light is test light, wherein the test light is directed to the prism (10) and is incident on the light The incident angle of the hypotenuse of the prism (10) at the surface plasma resonance angle 1250269 The first reference phase signal or the first reference light intensity signal of the reference light is measured by the photodetector (40); and the first test phase signal of the test light is measured by the optical detector (40) Or a first test light intensity signal; when the object to be tested is rotated at a small angle together with the 稜鏡 (10), a second reference phase signal or a second reference light intensity signal is generated, and the second test phase signal or the second test light is generated. The intensity signal; and the calculation of the first and second reference phase signals and the first and second test phase signals or the first and second reference light intensity signals and the first and second test light intensity signals are transmitted through the computer (50) And comparing the established phase difference or reflectance ratio to the parameter value database, and then converting the angle between the 稜鏡(10) and the rotation direction and rotation of the object to be tested. Referring to the fifth embodiment, when the preferred embodiment of the present invention is implemented, if the phase difference is compared with the parameter value database, the light source used is a heterodyne light source (21), and the light detection is performed. Before the device (40), the reference light and the test light are passed through the analyzer, and after the photodetector, the phase signal is obtained by the phase comparator (60), and then input into the computer (5〇) for calculation. Referring to the sixth embodiment, when the preferred embodiment of the present invention is implemented, if the ratio of reflectance to the parameter value database is established, the light source used is linear polarized laser light (22), directly lighted. The detector (4〇) measures the reference light and the test light signal, and then inputs it into the computer (50) for calculation. Referring to the seventh embodiment, in the preferred embodiment of the present invention, the measured angle of rotation is used, and then the light source is incident on the plane mirror (71) through the objective lens (70) and the counter is 1250269. The homing path 'uses the plane mirror σ υ fails to cause the reflected light to converge or diverge when the focal plane of the objective lens (70), and then uses the divergent or convergent light to enter the 稜鏡 (10) at the surface plasma resonance angle When the vicinity causes different phase difference values, the phase difference value is compared with the originally measured rotation angle to obtain a small displacement amount of the object plane to be tested. Referring to the first to seventh embodiments, a preferred embodiment of the present invention includes: a crucible (10) capable of generating a plasma resonance effect, the crucible (10) reflecting edge provided with at least one metal film (11), wherein the metal film (11) is made of gold; a light source device (20); a beam splitter (3〇) that reflects and transmits the light source; and at least one light for detecting light A detector (4); and a computer (50) for processing and calculating signals from the photodetector (40) to obtain a correlation value. Referring to the first embodiment, in the preferred embodiment of the present invention, the 稜鏡(1〇) reflective side is provided with two layers of heterogeneous metal film (11). Referring to the first embodiment, in the preferred embodiment of the present invention, the 稜鏡(1〇) reflective edge is provided with three layers of heterogeneous metal film (12). Referring to the fifth and sixth figures, in the preferred embodiment of the present invention, the crucible (10) is disposed on a rotating table (13). Referring to FIG. 5, when the preferred embodiment of the present invention is implemented, the light source device (20) is a heterodyne light source (21)' and an analyzer (80) is disposed in front of the photodetector (40). . Referring to the sixth embodiment, in a preferred embodiment of the present invention, the light source device 1250269 (20) is a linear polarized light source (22), and a bias is disposed on the path of the light source (22) to emit light. Board (23). Referring to the eighth and ninth figures, in the preferred embodiment of the present invention, the objective lens (70) and the plane mirror (71) are further included, so that the light source is incident on the plane mirror through the objective lens (7〇) (71). ) and reflected back to the original path. Referring to the first to third figures, the preferred embodiment of the present invention is based on the Kretschmaim four-layer structure. The first layer is 稜鏡(1〇), the refractive index is 以, and the first layer is The metal film has a refractive index of n2, the third layer is another metal film having a refractive index of n3, the fourth layer is air, and its refractive index is η4=: ι·〇, and the incident light is reflected by the “n2n3n4 reflection coefficient”. Γ1234 L 4+'严〆2 1+«34严〆2 -(2) is the reflection coefficient of the second layer from the first layer to the second and fourth layers; 4 is the film thickness of the third layer ·〆 can represent the S or p pole, the reflection coefficient of the i5/-<i layer to the small layer in the basin, and E^Jj Yk t = p I = i,j · ·
Cd 卜一 s I = iJ l”，^- = U3,4——(3) 其中“是代表在介質M中z方向上的波數(醜_ber)，根據 表面電漿共振理論，產生表面電漿波之條件 ^zi(j) = K[nfa) -nx sin2 θ{)----------------- (4) 1250269 其中為光在真空中傳播的波數，β為光由介質1入射介質2之入 射角，當第（4)式滿足時，於金屬膜(11)的邊界即發生表面電漿波， 水平偏極之反射光強度會突然驟減。 若分別用不同偏極的光S與Ρ偏極入射時，所得到反射係數分別為 表示如下： r1234 =|r1234^^P，^1234 =|r1234^^-----------------------⑸ 其中A與么代表P偏極與S偏極反射後所引入的相位延遲，而兩者 之間有一個相位差，即 δα ⑹ 若以反射強度表示時 [Λ1234 =|^34| 2 ^ 丨心H‘|2 J ⑺ 本發明模擬之例當中，令^為玻璃(BK7)，〜為鈦(τ〇 ,〜為 金(Au)其中鈦之厚度為2咖，金的厚度為43 lnm，所得共振角為 38其反射率(R)與相位差⑴分別對入射角《作圖得第二圖及第 三圖之結果，由此可知，反射率與相位差對在共振角附近的變化量 極其明顯，且線性度相當好，故非常適合為微小角度量測之用。 請參看第四圖所示，若要得到相位差值占，可以利用共光程外 差干涉原理而得’S偏極光與ρ偏極光之間有一頻差（由一個外差光 源⑵)提供)參考光由分光鏡⑽财反射後經檢偏娜⑺取出兩 光部份分量後干涉所得的參考信號為 1250269 7r =/ra(l + ^rcos(^ + ^r))----------------—-------------------⑻ 而分光鏡(30)之牙透光經待測物之後’（本實施例中，待測物為鍍 有金屬薄膜(11)的棱鏡(10)，其入射稜鏡(10)斜邊的角度為的表面電 漿共振角，如模擬的結果約43·8。附近），經檢偏板(80)取出兩偏極各 別的分量後干涉，而得到測試信號為 = +v； cos⑽ + --------------------------------------- ) 其中έϋ為干涉信號之角頻率； 久為參考信號的平均光強度，對比度與相位值； Φ 為測试彳§號的平均光強度，對比度與相位值， 兩信號分別由光偵測器(40)z>r&A偵測轉換得到電信號，並由相位 比較器（60)(如相位計或鎖相放大器）得出測試信號對參考信號之 相位差，扣除初始相位差即可得到待測相位差值5，此初始相位差 為BS之穿透光未經待測物之前，其干涉信號與參考信號之相位差。 請參看第五圖所示，係為本發明微小角度量測系統架構，係為 相位法’調整旋轉平台(13)，使入射稜鏡(10)斜邊角度剛好等於表· 面電漿波之共振角，並測得的相位變化經電腦(5〇)自動量測與運算 後’即可得到旋轉的方向與角度。 * 請參看第六圖所示，係為強度法，光源可採用線性偏極光(22)， 經分光鏡(30)反射的為參考光，此光經光偵測器（4〇)測得相當於入 射光強度/r ’將BS穿透的為測試光，此光經待測稜鏡反射在經由光 债測器（40)得到測試光強度（，將兩信號相除即f即可換算出反射 ^ r 12 1250269 率/之值。 請參看第七圖所示，本發明微小位移測量時，當一平行光入 射一物鏡(70)，平面反射鏡(71)位置剛好位於此物鏡(7〇)焦平面上 時，反射光束沿原路徑返回，且光束大小不變，當平面反射鏡(71) 離開焦平面而靠近物鏡(70)時，反射光變為發散光，若當平面反射 鏡(71)離開焦平面而遠離物鏡(70)，此反射光變為收斂光，其邊緣 光線之角度的改變量為ΔΘ 〇〇 吾δζ —------------------------(1〇) · 即ΔΘ正比於位移量(其中D為光束在物鏡(70)上的直徑，[為 物鏡(70)的焦距’ 為平面反射鏡(71)的位移量），將此反射光入 射如同微小角度量測時所用的稜鏡，平面鏡為於焦平面之反射光剛 好入射於稜鏡的入射角為共振角時，若當此平面鏡位移產生發散或 收斂光，取該光之邊緣利用測量角度的方法測得^之大小與方向， 即可測得位移的大小與方向，由此方法可測得微小之位移量，適合 作為顯微量測與定位之用。 鲁 請參看第八圖所示，係為本發明以相位法量測微小位移之基本 架構’外差光源(21)為具有兩個偏極(s偏極與ρ偏極)且其差頻為 * ⑺之雷射光源經分光鏡(BS)穿透後入射物鏡(70)，再由平面反射鏡 (71)反射返回原路徑，然後再經此反射又入射於具有鍍膜的稜鏡 (10) ’於稜鏡(10)的另一端面射出其入射角剛好位於表面電裝波共 振角，此反射光經檢偏板，取出S偏極與ρ偏極光之部份分量干涉， 13 1250269 此干涉面光之信號，由有一個一維的線性光偵測器偵測其上之所有 干涉信號，取出此一維線性光偵測器(40)之邊緣部份的兩個信號（么 與A)做相立比較（βϋ)，此j之大小正比於光束的發散或收 敛角度，亦正比於平面反射鏡㈤位移量的大小，故由測出相位差 值進而得出微小位移量。 凊參看第九圖所示，係為強度法量測微小位移之基本架構 圖，其所使”射歧(22)為線性偏極，為雜其躲平偏極光， 所以另加-個偏極板(23)，使出射光為水平偏極光。該稜鏡之出射# 光經-維線性光偵測器(40)量測其光束兩邊緣之光強度(Α與β)，利 用公式而得到相當於反射率差的公式，由於此信號正比於光 束發散或收斂的角度’亦正比於平面反射鏡(71)位移量的大小故 由測出光強度值進而得出微小位移量。 因此’藉由上述之結構設計，可歸納本發明確實具有下列所述 之優點·· 1. 本發明乃利用表面電漿共振原理結合共光程外差干涉儀高精嫁# 穩定的優點，因而可測出在共振角附近之相位與強度的變化，及 換算出入射光的角度，並由相位差或光強度的改變，即可知其旋* 轉的方向與轉肖度的大小，目此，本發明確實可提升量測時的 精準度及精確度。 2. 本發明乃利用表面電漿共振原理結合共光程外差干涉儀，因而可 應用於各種移動平台各軸向的偏轉之測量及光料其他系統之 14 1250269 校正，安裝，對準以及可延伸做為顯微鏡定位技術等方面之應 用’因此，本發明確實深具產業之利用性。 以上所述’僅為本發明之一可行實施例，並非用以限定本發明 之專利範圍，凡舉依據下列申請專利範圍所述之内容、特徵以及其 精神而為之其他變化的等效實施，皆應包含於本發明之專利範圍 内。本發明所具體界定於申請專利範圍之結構特徵，未見於同類物 品，且具實用性與進步性，已符合發明專利要件，爰依法具文提出 申請，謹請鈞局依法核予專利，以維護本申請人合法之權益。 _ 【圖式簡單說明】 第一圖係本發明表面電漿共振原理示意圖； 第二圖係本發明在共振角附近時之反射率對入射角的反應曲線示 意圖； 第三圖係本發明在共振脑近時相位差對人射角之反應曲線示意 圖， 第四圖係本發明之共光程外差干涉儀之示意圖； _ 第五圖係本發明以相位法量測微小角度架構示意圖； 第六圖係本發明以強度法量測微小角度架構示意圖； 第七圖係本發明之微小位移測量示意圖。 第八圖係本發明以相位法量測微小位移架構示音圖。 第九圖係本發明以強度法量測微小位移架構示意圖。 【主要元件符號說明】 (10)稜鏡 （11)(12)金屬膜 （13)旋轉台 15 1250269 (20)光源裝置 (23)偏極板 (50)電腦 (70)物鏡 (21)外差光源 （22)線性偏極雷射光源 (30)分光鏡 （40)光偵測器 (60)相位比較器（鎖相放大器或相位計） (71)平面反射鏡 （80)檢偏板Cd 卜 I s I = iJ l", ^- = U3,4 - (3) where "is the wave number in the z direction in the medium M (ugly _ber), according to the surface plasma resonance theory, the surface is generated The condition of the plasma wave ^zi(j) = K[nfa) -nx sin2 θ{)----------------- (4) 1250269 where the light propagates in the vacuum The wave number, β is the incident angle of light incident on the medium 2 by the medium 1. When the formula (4) is satisfied, the surface plasma wave occurs at the boundary of the metal film (11), and the intensity of the reflected light of the horizontally polarized pole suddenly rises. Less. If the light S and the ytterbium pole are respectively incident with different polarities, the obtained reflection coefficients are respectively expressed as follows: r1234 =|r1234^^P, ^1234 =|r1234^^---------- -------------(5) where A and ー represent the phase delay introduced by P-polarization and S-polarization reflection, and there is a phase difference between them, ie δα (6) When the intensity is expressed [Λ1234 =|^34| 2 ^ 丨心H'|2 J (7) In the simulation example of the present invention, ^ is glass (BK7), ~ is titanium (τ〇, ~ is gold (Au) where titanium The thickness is 2 coffee, the thickness of gold is 43 lnm, and the obtained resonance angle is 38. The reflectance (R) and the phase difference (1) respectively give the results of the second and third figures for the incident angle. The reflectance and phase difference are extremely obvious in the vicinity of the resonance angle, and the linearity is quite good, so it is very suitable for small angle measurement. Please refer to the fourth figure, if you want to get the phase difference account, you can Using the common path heterodyne interference principle, there is a frequency difference between the 'S polarized light and the ρ polarized light (provided by a heterodyne light source (2)). The reference light is reflected by the beam splitter (10) and then taken out by the detector (7). The reference signal obtained by partial component interference is 1250269 7r =/ra(l + ^rcos(^ + ^r))---------------------- ------------- (8) After the teeth of the beam splitter (30) are transmitted through the object to be tested (in the present embodiment, the object to be tested is a prism coated with a metal film (11) ( 10), the angle of the oblique edge of the incident 稜鏡 (10) is the surface plasma resonance angle, as the result of the simulation is about 43·8. nearby), after the differential plate (80) takes out the respective components of the two polarized poles Interference, and get the test signal as = +v; cos(10) + ------------------------------------- -- ) where έϋ is the angular frequency of the interference signal; long is the average light intensity of the reference signal, contrast and phase value; Φ is the average light intensity of the test 彳§, contrast and phase values, and the two signals are respectively detected by light The device (40)z>r&A detects the converted electrical signal, and the phase comparator (60) (such as a phase meter or a lock-in amplifier) obtains the phase difference between the test signal and the reference signal, and subtracts the initial phase difference. Obtaining a phase difference 5 to be measured, which is the interference signal and the reference signal before the transmitted light of the BS is not the object to be tested. Phase difference. Please refer to the fifth figure, which is the micro-angle measurement system architecture of the present invention. The phase method is to adjust the rotating platform (13) so that the angle of the oblique side of the incident 稜鏡 (10) is exactly equal to the surface of the plasma wave. The resonance angle and the measured phase change are automatically measured and calculated by the computer (5〇) to obtain the direction and angle of rotation. * Please refer to the figure 6 for the intensity method. The light source can be linearly polarized (22), and the light reflected by the beam splitter (30) is the reference light. The light is measured by the photodetector (4〇). The incident light intensity /r ' penetrates the BS as the test light, and the light is reflected by the to-be-measured 在 to obtain the test light intensity via the optical debt detector (40) (the two signals are divided by f, then the light can be converted Reflection ^ r 12 1250269 rate / value. Referring to the seventh figure, when measuring the micro-displacement of the present invention, when a parallel light is incident on an objective lens (70), the position of the plane mirror (71) is located at the objective lens (7〇). When the focal plane is on, the reflected beam returns along the original path, and the beam size does not change. When the plane mirror (71) leaves the focal plane and approaches the objective lens (70), the reflected light becomes divergent light, if it is a plane mirror ( 71) Leaving the focal plane away from the objective lens (70), the reflected light becomes a convergent light, and the angle of change of the edge of the edge light is ΔΘ 〇〇 ζ δ ζ —--------------- ---------(1〇) · That is, ΔΘ is proportional to the displacement (where D is the diameter of the beam on the objective lens (70), [the focal length of the objective lens (70) is a plane mirror (71) (the amount of displacement), the reflected light is incident as measured by a small angle measurement, the plane mirror is the incident angle of the reflected light at the focal plane just incident on the 为 is the resonance angle, if the plane mirror displacement produces divergence Or converging the light, taking the edge of the light to measure the size and direction of the ^ by measuring the angle, the magnitude and direction of the displacement can be measured, and the method can measure the small displacement amount, which is suitable for microscopic measurement and For the purpose of positioning, please refer to the eighth figure, which is the basic structure of measuring the micro-displacement by the phase method. The heterodyne light source (21) has two polarized poles (s-polar and ρ-polar) and The laser source with the difference frequency of * (7) is transmitted through the beam splitter (BS) and then incident on the objective lens (70), and then reflected by the plane mirror (71) back to the original path, and then reflected and incident on the edge with the coating. The mirror (10) 'the other end face of the 稜鏡(10) emits its incident angle just at the surface electrical wave resonance angle. The reflected light passes through the analyzer, and the S-polarizer and the ρ-polarized light are interfering with each other. 13 1250269 This interference surface light signal has a one-dimensional linear The photodetector detects all the interference signals thereon, and takes out two signals (? and A) of the edge portion of the one-dimensional linear photodetector (40) for comparison (βϋ), the size of the j It is proportional to the divergence or convergence angle of the beam, and is also proportional to the displacement of the plane mirror (5). Therefore, the phase difference is measured to obtain a small displacement. 凊 See the ninth figure, which is measured by the intensity method. The basic structural diagram of the displacement, which makes the "fission (22) linearly polarized, for the misalignment of the aurora, so add a polarizing plate (23), so that the outgoing light is horizontally polarized. The exit of the mirror #光经-dimensional linear light detector (40) measures the light intensity (Α and β) of the two edges of the beam, and uses the formula to obtain the formula corresponding to the reflectance difference, since this signal is proportional to the beam divergence Or the angle of convergence 'is also proportional to the magnitude of the displacement of the plane mirror (71), so that the light intensity value is measured to obtain a small amount of displacement. Therefore, by the above structural design, it can be concluded that the present invention does have the advantages described below. 1. The present invention utilizes the principle of surface plasma resonance to combine the advantages of the common optical path heterodyne interferometer with high precision. The phase and intensity changes around the resonance angle can be measured, and the angle of the incident light can be converted, and the phase difference or the light intensity can be changed to know the direction of the rotation and the degree of the rotation. The invention does improve the accuracy and precision of the measurement. 2. The invention utilizes the surface plasma resonance principle combined with the common optical path heterodyne interferometer, and thus can be applied to the measurement of the deflection of each axial direction of various mobile platforms and the 14 1250269 calibration, installation, alignment and other systems of other light materials. The extension is used as an application for microscope positioning technology. Therefore, the present invention is indeed industrially usable. The above description is only one of the possible embodiments of the present invention, and is not intended to limit the scope of the patents of the present invention, and the equivalents of other variations of the contents, the features and spirit of the following claims, All should be included in the scope of the patent of the present invention. The invention is specifically defined in the structural features of the scope of the patent application, is not found in the same kind of articles, and has practicality and progress, has met the requirements of the invention patents, and has applied for the law according to law, and invites the bureau to approve the patents according to law to maintain The legal rights of the applicant. BRIEF DESCRIPTION OF THE DRAWINGS The first figure is a schematic diagram of the surface plasma resonance principle of the present invention; the second figure is a schematic diagram of the response curve of the reflectance to the incident angle when the present invention is near the resonance angle; Schematic diagram of the response curve of the near-phase phase difference to the human angle of incidence, and the fourth diagram is a schematic diagram of the common optical path heterodyne interferometer of the present invention; _ The fifth diagram is a schematic diagram of the micro-angle architecture measured by the phase method of the present invention; BRIEF DESCRIPTION OF THE DRAWINGS The present invention is a schematic diagram of a micro-angle architecture measured by a strength method; and a seventh diagram is a schematic diagram of a micro-displacement measurement of the present invention. The eighth figure shows the sound map of the micro-displacement structure measured by the phase method. The ninth figure is a schematic diagram of the micro-displacement structure measured by the strength method of the present invention. [Description of main component symbols] (10) 稜鏡 (11) (12) metal film (13) rotary table 15 1250269 (20) light source device (23) polarized plate (50) computer (70) objective lens (21) heterodyne Light source (22) Linear polarized laser source (30) Beam splitter (40) Photodetector (60) Phase comparator (lock-in amplifier or phase meter) (71) Planar mirror (80) analyzer
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