TWI247091B

TWI247091B - Apparatus for measuring displacement

Info

Publication number: TWI247091B
Application number: TW93134250A
Authority: TW
Inventors: Ju-Yi Lee; Hsueh-Ching Shih
Original assignee: Ind Tech Res Inst
Priority date: 2004-11-10
Filing date: 2004-11-10
Publication date: 2006-01-11
Also published as: TW200615505A

Abstract

The present apparatus for measuring displacement comprising a laser source for generating a light beam, a stand for loading a sample, an object lens positioned between the laser source and the stand, a reference mirror positioned between the object lens and the stand, a beam splitter positioned between the reference mirror and the stand, a wave plate positioned between the first beam splitter and the stand, and a phase detector for detecting signals representing the displacement of the sample. The beam splitter splits the light beam into a reference beam and an object beam, which is then reflected by the reference mirror and the sample respectively and overlaps to form an interfered light. The phase detector can generate two signals with 90 degrees of phase difference from the interfered light. The wave plate can be a polarization phase retarder or a 1/8 wave plate, and the object beam passes through the wave plate twice.

Description

1247091 九、發明說明：【發明所屬之技術領域】本叙明係關於一種位移量測裝置學相你p 」衣置4寸別係關於一利用光子相位正父干涉技術之位移量測裝置。【先前技術】、干涉儀已經普遍地應用於非接觸式振動量測及超音波偵測領域。目前國内相關量測產業仍處於萌芽階段，多倚賴國1 卜薇商提供精密的量測能力。高品質的量測系統是發展 ;:山產業的；^關鍵，’然而由於技術觀頸以及材料成本一直居高不下，對國内業者提高技術品質—直是—個沉重的負擔。，目前常見的干涉儀類型包括··白光干涉儀，都卜勒干涉儀’ Fabry-per0t干涉儀等。依特性不同，這些干涉儀分別應用在不同的量測領域。例如，白光干涉儀可測量表面輪廓，都卜勒干涉儀可測量振動量，Fabry_Per〇t干涉儀則用來分析光譜或更為精密位移量測。傳統干涉顯微鏡係利用移相干涉術（Phase Shifting Interferometry，PSI)或掃瞄白光干涉術（Scanning White Light Interferometry，SWLI)，以指頁取試片表面輪廓資訊。然而，這兩項技術並無法獲得試片局部區域的動態行為資訊。圖1係一習知表面輪廓量測裝置1〇之示意圖，由1247091 IX. INSTRUCTIONS: [Technical field to which the invention pertains] This description relates to a displacement measuring device. You can use a displacement measuring device that utilizes the photon phase positive father interference technique. [Prior Art] Interferometers have been commonly used in the field of non-contact vibration measurement and ultrasonic detection. At present, the relevant domestic measurement industry is still in its infancy, relying more on Lai Guo 1 Bu Wei Shang to provide sophisticated measurement capabilities. High-quality measurement systems are development;: mountain industry; ^ key, 'But due to the high level of technology and material costs, it is a heavy burden for domestic players to improve their technical quality. Currently, the types of interferometers commonly used include white light interferometers, Doppler interferometers, and Fabry-per0t interferometers. Depending on the characteristics, these interferometers are used in different measurement fields. For example, a white light interferometer can measure the surface profile, a Doppler interferometer can measure the amount of vibration, and a Fabry_Per〇t interferometer can be used to analyze the spectrum or more precise displacement measurements. Conventional interference microscopy uses Phase Shifting Interferometry (PSI) or Scanning White Light Interferometry (SWLI) to refer to the surface contour information of the test piece. However, these two techniques do not provide information on the dynamic behavior of the local area of the test strip. Figure 1 is a schematic view of a conventional surface profile measuring device 1

Sandoz 與 Gilbert Tribillon 在 1993 發表（參考：，，profil〇metry by zero-order interference fringe identification”，Journal of modern optics，1993, v〇l. 40, No. 9, page 1691-1700)。一光 PD0082 doc 1247091 源12發出之光線14經由一⑽削型干涉物鏡 ^上。該光線14經由—半反射㈣分成—物光u及」 ^24,其中該物光22經由該試片3。與一分光鏡16反射到達一咖感測器28，而該參考光24則由該半反射鏡⑽— 參考面鏡26反射後經由該分光鏡_達該咖感測器28。口亥麥考光24與該物光22万相不、半Sandoz and Gilbert Tribillon were published in 1993 (reference:, profil〇metry by zero-order interference fringe identification), Journal of modern optics, 1993, v〇l. 40, No. 9, page 1691-1700). A light PD0082 Doc 1247091 The light 14 emitted by the source 12 is passed through a (10) shaving interference objective. The light 14 is split into - object light u and "24" via a semi-reflective (four), wherein the object light 22 passes through the test strip 3. And a beam splitter 16 is reflected to the coffee sensor 28, and the reference light 24 is reflected by the half mirror (10) - the reference mirror 26, and then passes through the beam splitter to reach the coffee sensor 28. Mouth Haimai Kaoguang 24 and the object light 220,000 phase, half

β、_ 互相干涉，而干涉條紋則由該CCD 感測裔2 8取像後再作分析。由於採用低同調度的井源干涉條紋的對比度會隨者九私差增加而迅速遞減。^庐振‘取大條紋稱為零階條紋，表示由該試片30之表面及号τ灸衣面及π亥芩考面鏡2 6反射的光線所走的相同的。利用一麼電制動器（PZT actuator)32讓亨紹咖型干涉物鏡2G在軸向掃猫，並將零階條紋出現的橫向z 位置與該壓電制動器32的位私里5己錄下來’即可獲得該試片30的表面輪摩資訊。【發明内容】本發明之主要目的係提供-種利用光學相位正交干涉技術之位移量測裝置。 x 為達成上述目的，本發明揭示—種利用光學相位正涉技術之位移量測裝置。該位移量測裝置包含―可發出— 光束之雷射光源、-可承载—試片之載台、一設置於” 射光源與該載台間之物鏡、—設置於該物鏡與該載台二蒼考面鏡、-設置於該參考面鏡與該載台間之分光鏡、— 設置於該分光鏡與該載台間之波片以及—用以偵測該試片之位移訊號的相位正交偵測器。該分光鏡可將該光束分成 1247091 -參考光及-物光，該參考光及該物光分別經由該鏡及該試片反射後重疊而產生一干涉光，而該相位測器則根據該干涉光產生二相位差9〇度之訊號。該波片可為-相位延遲片或-1/8波長板，且該物光經過該波: 次。一【實施方式】圖2例示本發明之位移量測裝置4〇。該位移量測裝置4〇包含一可發出一光束54之雷射光源52、—可承載一試片66 之載台50、一設置於該雷射光源52與該載台5〇間之物鏡 56、一設置於該物鏡56與該載台5〇間之參考面鏡6〇、—設置於該參考面鏡60與該載台50間之分光鏡58、一設置於該分光鏡58與該載台5G間之波片68以及—用以偵測該試片二之位移訊號的相位正交偵測器8 〇。該分光鏡58可將該光束54分成一參考光62及一物光64，該參考光62及該物光64分別經由該參考面鏡6〇及該試片66 反射後重疊而產生一干涉光7〇，而該相位正交偵測器⑽則根據該干涉光70產生二相位差9〇度之位移訊號。該波片68 可為一相位延遲片或一 1/8波長板，且該物光64通過該波片 68二次。特而言之，該物光64先通過該波片68後照射於該忒片66，並經由該忒片66反射後再穿過該波片68。該相位正父偵測為80包含一可將該干涉光7〇分成一水平偏振光82 及一垂直偏振光84之極化分光鏡9〇、二個用以偵測該水平偏振光82及該垂直偏振光84之強度的光偵測器“及88以及一可根據該光偵測器86及88之輪出計算該試片66之位移量 1247091 的訊號處理器72。圖3及圖4例示本發明位移量測裝置4〇之量測結果。該物光64、、.工過。亥波片68一次’而該參考光則未經過該波片68。假設該光束54是45度的線性偏振光，則其電場的j_，s vector可寫為(上標τ表示矩陣轉置），其中為了方便計算起見而忽略振幅項。該參考光62因未經過該波㈣，因而仍為45度的線性偏振光，其電場的】。心獸如仍為 [ι，ι]τ。相對地’該物光64經過該波片68作用二次，使其線性偏振光變成-圓偏振光，其冑場的—A為 π，心#，其中❻該參考光62與該物光64之光程差所引入的相位差。因此’只要將光程差解出’即可得知該試片66之表面位移或振動。該參考光62與該物光64重疊後之干涉光7〇之電場的Tone’s v⑽。r可寫為為[W，1 + ,外。該極化分光鏡％將該干涉光70分光，使得嗲氺伯于以光偵測為86僅可收到該水平偏振光82，其光電場形式為1 +以；而該光偵測器则僅收到吕亥垂直偏振光8 8，其弁雷错你々法 > 、九电％形式為丨+β。由於光強度正比於光電場的絕對平方值（水祙日|丨2 j 1 (也就疋卜叫或卜叫2)，因此該光债測器8 6及8 8之輸出訊缺4同2 ό _ 札號如圖3所不，其中曲線87係該光偵測器86之輸出(/,)，而曲線89則為該光偵測器μ之輸出 (^2 ) ^分別為： ’oci + Aci C0Si^ ⑴ ZIDC2 +IAC.2 ^ηΦ (2) ^1^0082.doc Ϊ247091 ()()兩式中的7°c與4分別是該光债測器、86及88之輸出 Λ號的直流與交流項。我們要求的是相位項，因此可將 (1)(2)兩式調整為： COS0 DC) AC] (3) siru DC 2 ' AC2 (4) DC]β and _ interfere with each other, and the interference fringes are analyzed by the CCD sensory image. Due to the low-synchronized well-source interference fringes, the contrast ratio will decrease rapidly as the nine-difference increases. ^庐振's large stripe is called the zero-order stripe, which means that the surface of the test strip 30 and the light reflected by the surface of the moxibustion mask and the π 芩芩 2 mirror 26 are the same. Using an electric brake (PZT actuator) 32, the Hensauer type interference objective lens 2G sweeps the cat in the axial direction, and the lateral z position where the zero-order stripe appears and the position of the piezoelectric brake 32 are recorded. The surface wheel information of the test piece 30 can be obtained. SUMMARY OF THE INVENTION A primary object of the present invention is to provide a displacement measuring device using optical phase orthogonal interference technique. x To achieve the above object, the present invention discloses a displacement measuring device utilizing an optical phase dependent technique. The displacement measuring device comprises: a laser light source capable of emitting a light beam, a carrier capable of carrying a test piece, an objective lens disposed between the light source and the stage, and disposed on the objective lens and the stage a Cang test mirror, a beam splitter disposed between the reference mirror and the stage, a wave plate disposed between the beam splitter and the stage, and a phase for detecting a displacement signal of the test piece The beam splitter can divide the light beam into 1247091 - reference light and - object light, and the reference light and the object light are respectively reflected by the mirror and the test piece and overlap to generate an interference light, and the phase measurement The device generates a signal with a phase difference of 9 degrees according to the interference light. The wave plate can be a phase retarder or a -1/8 wavelength plate, and the object light passes through the wave: times. [Embodiment] FIG. The displacement measuring device 4 of the present invention is illustrated. The displacement measuring device 4 includes a laser light source 52 that emits a light beam 54, a stage 50 that can carry a test piece 66, and a laser light source disposed on the laser light source. An objective lens 56 between the 52 and the stage 5, and a reference surface disposed between the objective lens 56 and the stage 5 6〇, a beam splitter 58 disposed between the reference mirror 60 and the stage 50, a wave plate 68 disposed between the beam splitter 58 and the stage 5G, and — for detecting the test strip 2 The phase quadrature detector of the displacement signal is 8. The beam splitter 58 can divide the beam 54 into a reference light 62 and an object light 64. The reference light 62 and the object light 64 are respectively connected via the reference mirror 6 The test strip 66 is reflected and overlapped to generate an interference light 7〇, and the phase quadrature detector (10) generates a displacement signal with a phase difference of 9 degrees according to the interference light 70. The wave plate 68 can be a phase delay. a sheet or a 1/8 wavelength plate, and the object light 64 passes through the wave plate 68 twice. In particular, the object light 64 passes through the wave plate 68 and then illuminates the cymbal sheet 66 and passes through the cymbal sheet 66. The reflection 66 then passes through the wave plate 68. The phase positive parent detection 80 includes a polarization beam splitter 9〇, which can divide the interference light 7 into a horizontally polarized light 82 and a vertically polarized light 84. A photodetector "and 88" for detecting the intensity of the horizontally polarized light 82 and the vertically polarized light 84 and a round-out calculation according to the photodetectors 86 and 88 The test piece 66 has a displacement amount of 1247091 of the signal processor 72. 3 and 4 illustrate the measurement results of the displacement measuring device 4 of the present invention. The object light 64, , worked. The wave plate 68 is once' and the reference light does not pass through the wave plate 68. Assuming that the beam 54 is linearly polarized at 45 degrees, the j_, s vector of its electric field can be written as (superscript τ indicates matrix transposition), with the amplitude term being ignored for convenience of calculation. The reference light 62 is still 45 degrees of linearly polarized light due to the absence of the wave (4), and its electric field. The heart beast is still [ι,ι]τ. Relatively, the object light 64 acts twice through the wave plate 68 to change its linearly polarized light into a circularly polarized light, and its field A is π, heart #, wherein the reference light 62 and the object light 64 The phase difference introduced by the optical path difference. Therefore, the surface displacement or vibration of the test piece 66 can be known by simply solving the optical path difference. Tone's v(10) of the electric field of the interference light 7〇 after the reference light 62 overlaps the object light 64. r can be written as [W, 1 + , outside. The polarization beam splitter % splits the interference light 70 so that the light is detected by the light 86 and only the horizontally polarized light 82 is received, and the optical electric field is in the form of 1 +; and the photodetector is Only received Luhai vertical polarized light 8 8, its 弁错々々 & & & 九九九九九九九九九九九九九九九九九Since the light intensity is proportional to the absolute square value of the optical electric field (祙水祙|丨2 j 1 (also called 疋或 or 卜 2), the output of the optical debt detectors 8 6 and 8 8 is the same as 2 ό _ The number is as shown in Figure 3, where curve 87 is the output (/,) of the photodetector 86, and curve 89 is the output of the photodetector μ (^2) ^ respectively: 'oci + Aci C0Si^ (1) ZIDC2 + IAC.2 ^ηΦ (2) ^1^0082.doc Ϊ247091 The 7°c and 4 in the two equations are the output nicknames of the optical debt detectors, 86 and 88 respectively. DC and AC terms. We require phase terms, so we can adjust (1)(2) to: COS0 DC) AC] (3) siru DC 2 ' AC2 (4) DC]

DC2、1AC' 反 I AC2 -般的電+電路可以輕易地測得到因此與光程差有關的相位可寫為：DC2, 1AC' anti-I AC2 - the general electric + circuit can be easily measured. Therefore, the phase related to the optical path difference can be written as:

(5) 根據光學的公式， μ σ狁處理器72可從該光偵測器86：ί 輸出（A )及該光债測哭8只 …叙、θ U之輪出⑷計算該試片66之㈣ (或振動如圖4所示，1 關係為·· 〃中^式片66之位移⑷與相位差白(5) According to the optical formula, the μ σ 狁 processor 72 can calculate the test piece 66 from the photodetector 86: ί output (A) and the optical debt test crying 8 (s), θ U round out (4) (4) (or vibration as shown in Figure 4, 1 relationship is · · 〃中^-plate 66 displacement (4) and phase difference white

^(〇=2/cd(t)^2x^L ⑹ 或^(〇=2/cd(t)^2x^L (6) or

II

DCI ⑺ 礼I 一 “間α之，本發明係在傳統的Mlrau干涉物鏡中加入1、念 68，使該物光64變成兄十加入该波 ^ ^ . 、、光，再與線性偏振的參考# 產生遠干涉光7〇，然亏先個相位差90度的訊號。之、U〇取出後，再利用該訊號處理器72將 PD00S2.doc 1247091 二個訊號作運算即可得到該試片66之位移或振動量。圖5例示本發明另一實施例之相位正交偵測器丨〇〇。該相位正父偵測為100包含一可將該干涉光70分成二道子光束 104A及104B之分光鏡102、一可將該子光束104A分成二偏振光112及114之極化分光鏡11〇、一用以偵測該偏振光112 之強度的光偵測器11 6、一用以偵測該偏振光丨丨4之強度的光偵測器118、一可將該子光束1〇仙分成二偏振光122及124 之極化分光鏡120、一用以偵測該偏振光122之強度的光偵測|§ 126、一用以偵測該偏振光124之強度的光偵測器128、一將該光偵測器116與該光偵測器118之輸出訊號相減的差動放大器132、一將該光偵測器126與該光偵測器128之輸出訊號相減的差動放大器134以及一將該差動放大器132與該差動放大器134之類比輸出轉換成數位訊號的類比/數位轉換器136。DCI (7) 礼I a "inter-alpha", the invention is added to the traditional Mlrau interference objective lens 1, read 68, so that the object light 64 becomes the brother to join the wave ^ ^., light, and linear polarization reference # Generate far interference light 7〇, but lose the first signal with a phase difference of 90 degrees. After U〇 is taken out, use the signal processor 72 to calculate the PD00S2.doc 1247091 two signals to obtain the test piece 66. The displacement or the amount of vibration. Figure 5 illustrates a phase quadrature detector 另一 according to another embodiment of the present invention. The phase positive detection 100 includes a division of the interference light 70 into two sub-beams 104A and 104B. The beam splitter 102, the polarizing beam splitter 11 that divides the sub-beam 104A into two polarized lights 112 and 114, and a photodetector 11 for detecting the intensity of the polarized light 112, one for detecting The photodetector 118 of the intensity of the polarization pupil 4, a polarization beam splitter 120 that divides the sub-beam into a polarized light 122 and 124, and a polarity of the polarized light 122 are detected. Light detection|§ 126, a photodetector 128 for detecting the intensity of the polarized light 124, and the photodetector 1 a differential amplifier 132 that subtracts the output signal of the photodetector 118, a differential amplifier 134 that subtracts the output signal of the photodetector 126 and the photodetector 128, and a differential amplifier The amplifier 132 and the differential amplifier 134 output an analog/digital converter 136 that converts the digital signal into a digital signal.

5亥偏振光112與該偏振光114之相位差9〇产 122與該偏振光124之相位差90度。特的四個訊號，其數學形式可寫為：The phase difference between the 5 polarized light 112 and the polarized light 114 is 90 degrees out of phase with the polarized light 124. The special four signals, the mathematical form can be written as:

組合’則可得到正弦與餘弦信號如下：Combine ' to get the sine and cosine signals as follows:

(9) PDOOK2.doc 10 1247091 (10) Q^S[A]~A3+(B]+B2)cosφ} 若適當地調整該光偵測器116、118、126及128的增益，使得、卑二為與式，則可得到光程差所引進的相位差為： a ^πά , Ρ Φ = 〇 ⑴）此為該相位正交偵測器100取出相位的方法。而該試片66 之位移^(或振動）量可寫為 40: A Απ x tan"(9) PDOOK2.doc 10 1247091 (10) Q^S[A]~A3+(B]+B2)cosφ} If the gains of the photodetectors 116, 118, 126, and 128 are properly adjusted, For the equation, the phase difference introduced by the optical path difference is: a ^πά , Φ Φ = 〇(1)) This is the method by which the phase quadrature detector 100 takes out the phase. The displacement ^ (or vibration) of the test piece 66 can be written as 40: A Απ x tan"

Pit)W) (12)Pit)W) (12)

本發明之技術内容及技術特點已揭示如上，然而熟悉本項技術之人士仍可能基於本發明之教示及揭示而作種種不背離本發明精神之替換及修飾。因此，本發明之保護範圍應不限於實施例所揭示者，而應包括各種不㈣本發明之替換及修飾，並為以下之申請專利範圍所涵蓋。【圖式簡單說明】 1The technical contents and technical features of the present invention have been disclosed as above, and those skilled in the art can still make various substitutions and modifications without departing from the spirit and scope of the invention. Therefore, the scope of the invention should be construed as not limited by the scope of the invention, and the invention is intended to [Simple description of the schema] 1

圖1係一習知表面輪廓量測裝置之示意圖；圖2例示本發明第一實施例之位移量測裝置· 圖3及圖4例示本發明位移量測裝置之量測結果；以圖5例示本發明另一實施例之相位正交偵測界【主要元件符號說明】 °° 及 10 表面輪廓量測裝置1 2 14 光束 18 半反射鏡 22 物光光源 16 分光鏡 2〇干涉物鏡參考光 24 PD0082 doc 1247091 26 參考面鏡 28 CCD感測器 30 試片 32 壓電材料制動器 40 位移量測裝置 50 載台 52 雷射光源 54 光束 56 物鏡 58 分光鏡 60 參考面鏡 62 參考光 64 物光 66 試片 68 波片 70 干涉光 72 訊號處理器 80 相位正交偵測器 82 水平偏振光 84 垂直偏振光 86 光偵測器 87 曲線 88 光偵測器 89 曲線 90 極化分光鏡 100 相位正交偵測器 102 分光鏡 104A 子光束 104B 子光束 110 極化分光鏡 112 偏振光 114 偏振光 116 光偵測器 118 光偵測器 120 極化分光鏡 122 偏振光 124 偏振光 126 光伯測器 128 光偵測器 132 差動放大器 134 差動放大器 136 類比/數位轉換器1 is a schematic view of a conventional surface profile measuring device; FIG. 2 illustrates a displacement measuring device according to a first embodiment of the present invention. FIG. 3 and FIG. 4 illustrate measurement results of the displacement measuring device of the present invention; Phase quadrature detection boundary according to another embodiment of the present invention [Description of main component symbols] °° and 10 Surface profile measuring device 1 2 14 Light beam 18 Half mirror 22 Object light source 16 Beam splitter 2〇 Interference objective lens Reference light 24 PD0082 doc 1247091 26 Reference mirror 28 CCD sensor 30 Test strip 32 Piezoelectric brake 40 Displacement measuring device 50 Stage 52 Laser source 54 Beam 56 Objective lens 58 Beam splitter 60 Reference mirror 62 Reference light 64 Matte light 66 Test strip 68 Wave plate 70 Interference light 72 Signal processor 80 Phase quadrature detector 82 Horizontally polarized light 84 Vertically polarized light 86 Photodetector 87 Curve 88 Photodetector 89 Curve 90 Polarizing beam splitter 100 Phase orthogonal Detector 102 beam splitter 104A sub-beam 104B sub-beam 110 polarized beam splitter 112 polarized light 114 polarized light 116 photodetector 118 photodetector 120 polarized beam splitter 122 polarized light 124 partial Vibration 126 Optical detector 128 Photodetector 132 Differential amplifier 134 Differential amplifier 136 Analog/digital converter

PD0082.docPD0082.doc

Claims

1247091 十、申請專利範圍： 1. 一種位移量測裝置，包含·· 一雷射光源，可發出一光束；載台，可承載一試片；一物鏡，設置於該雷射光源與該載台之間；苓考面鏡，設置於該物鏡與該載台之間；一第一分光鏡，設置於該參考面鏡與該載台之間，可將该光束分成一參考光及一物光，該參考光及該物光分別、、二由。亥芩考面鏡及该試片反射後重疊而產生一干涉光；一波片，設置於該物光之光路上；以及一相位正交偵測器，其根據該干涉光產生二相位差90 度之訊號。如申請專利範圍第1項之位移量測裝置置於該第一分光鏡與該載台之間，且置，其中該波片係設且該物光經過該波片二次0 如申請專利範圍第2項之位移量測褒置其中該波片係一相位延遲波片。如申請專利範圍第2項之位移量測褒置 1 / 8波長板。 ’其中該波片係一如申請專利範圍第1項之位移量測褒置偵測器包含：其中該相位正交一極化分光鏡，垂直偏振光；1247091 X. Patent application scope: 1. A displacement measuring device, comprising: a laser light source, capable of emitting a light beam; a loading stage capable of carrying a test piece; an objective lens disposed on the laser light source and the stage Between the objective lens and the stage; a first beam splitter disposed between the reference mirror and the stage, the beam is divided into a reference light and a light The reference light and the object light are respectively separated by two. The mirror and the test piece overlap and reflect to generate an interference light; a wave plate is disposed on the light path of the object light; and a phase quadrature detector generates a phase difference 90 according to the interference light Signal of degree. The displacement measuring device according to claim 1 is placed between the first beam splitter and the stage, and the wave plate is tied and the object light passes through the wave plate twice. The displacement measurement of the second item is in which the wave plate is a phase retardation wave plate. For example, the displacement measurement of the second item of the patent application range is 1 / 8 wavelength plate. Wherein the wave plate is a displacement measuring device as in the first application of the patent scope: wherein the phase is orthogonal to a polarizing beam splitter, vertically polarized light;

一第一光偵測器，用以偵測該以偵測该水平偏振光之強度；以 PD0082.doc 1247091 )一罘二光偵測器，用以偵測該垂直偏振光之強度。二申料利範圍第5項之位移量測裝置，其另包含一訊號 A ’可根據該中該二光^貞測器之輸出計算該試片之位移量。 Λ如中請專利範圍第i項之位移量測裝置，其中該相位正交偵測器包含：一第二分光鏡，可將該干涉光分成二道子光束； —一第一極化分光鏡，可將該二道子光束之一分成一第一偏振光及一第二偏振光； —第一光偵測器，用以偵測該第一偏振光之強度；以及 8 一第二光偵測器，用以偵測該第二偏振光之強度。、>申月專利範圍第7項之位移量測裝置，其中該第一偏振光與該第二偏振光之相位差90度。 9·如申請專利範圍第7項之位移量測裝置，其中該相位正交偵測器另包含：一第二極化分光鏡，可將另一道子光束分成一第三偏振光及一第四偏振光；一弟三光偵測器，用以偵測該第三偏振光之強度；以及第四光偵測器，用以偵測該第四偏振光之強度。 10·如申請專利範圍第9項之位移量測裝置，《中該第三偏振光與"亥第四偏振光之相位差90度。 "·如申請專利範圍第9項之位移量測裝置，纟中該相位正交 POU082.doc -2- 1247091 偵測器另包含：一第一差動放大器，用以將該第一光偵測器與該第二光偵測器之輸出訊號相減；以及一第二差動放大器，用以將該第三光偵測器與該第四光偵測器之輸出訊號相減。 12.如申請專利範圍第11項之位移量測裝置，其中該相位正交偵測器另包含一類比/數位轉換器，用以將該第一差動放大器與該第二差動放大器之類比輸出轉換成數位訊號。A first photodetector is configured to detect the intensity of the horizontally polarized light; and a PD2082.doc 1247091) a photodetector for detecting the intensity of the vertically polarized light. The displacement measuring device of item 5 of claim 2 further includes a signal A ′ for calculating the displacement amount of the test piece according to the output of the two optical detectors. For example, in the displacement measuring device of the patent range i, wherein the phase quadrature detector comprises: a second beam splitter, the interference light can be divided into two sub-beams; a first polarization beam splitter, One of the two sub-beams may be divided into a first polarized light and a second polarized light; a first photodetector for detecting the intensity of the first polarized light; and a second photodetector And detecting the intensity of the second polarized light. The displacement measuring device of claim 7, wherein the first polarized light and the second polarized light are out of phase by 90 degrees. 9. The displacement measuring device of claim 7, wherein the phase quadrature detector further comprises: a second polarizing beam splitter that splits the other sub-beam into a third polarized light and a fourth Polarized light; a third light detector for detecting the intensity of the third polarized light; and a fourth photodetector for detecting the intensity of the fourth polarized light. 10. If the displacement measuring device of claim 9 is applied, the phase difference between the third polarized light and the fourth polarized light is 90 degrees. "·If the displacement measuring device of the ninth application patent scope, the phase orthogonal POU082.doc -2- 1247091 detector further comprises: a first differential amplifier for the first optical detection The detector is subtracted from the output signal of the second photodetector; and a second differential amplifier is used to subtract the output signal of the third photodetector and the fourth photodetector. 12. The displacement measuring device of claim 11, wherein the phase quadrature detector further comprises an analog/digital converter for analogizing the first differential amplifier with the second differential amplifier The output is converted to a digital signal.

PD0082 docPD0082 doc