九、發明說明： 【發明所屬之技術領域】 本發明係關於一種光學感測裝置及包含該光學感測裝置 之量測系統，詳言之’係關於一種可感測一待測物體表面 變化之光學感測裝置及包含該光學感測裝置之量測系統。 【先前技術】 TFT-LCD製程技術主要是將玻璃基板透過類似半導體製 造技術（鍍膜、曝光、顯影、蝕刻等技術）在基版上形成為 數眾多的電晶體。在進行製程瑕疵檢測時，一般皆須利用 人工或是機器手臂將該玻璃基板置放於一 TFT-LCD量測系 統上進行檢測。 參考圖1，顯示習知TFT-LCD量測系統之示意圖。該量 測系統1包括一透鏡裝置丨1、一 CCD鏡頭丨2、一定位平台 13及一信號處理裝置14。該透鏡裝置Η包括一物鏡，其係 為—維陣列透鏡。該CCD鏡頭12係透過該透鏡裝置u擷取 一物體1 5 (例如該玻璃基板）之影像。該物體1 5係置放於 —機台17上。該定位平台13包括一驅動馬達、一馬達軸控 制卡及一平台本體。該定位平台13係用以調整該透鏡裝置 11之焦距。該透鏡裝置11、該CCD鏡頭12及該定位平台13 係位於固定基板16上’使得該透鏡裝置11與該物體15間 隔一適當距離。該信號處理裝置1 4接受來自該CCD鏡頭12 之影像資料’且比較該影像資料之影像品質與其聚焦標 準’而產生一控制信號’進而將該控制信號傳送至該定位 平台13 ’以調整該透鏡裝置11之焦距。 I I6429.doc 1342387 在實際操作時，必須重複上述擷取影像_比對_調整焦距· 擷取影像之程序複數次直到該影像資料之品質符合該聚焦 標準為止。如此’將會浪費許多時間，而且此方式所擷取 之影像清晰標準並無一定之規範。 該量測系統1之另一個缺點為，該物體1 5置放於該機台 17上時，若受到一外部激振，將造成該物體15產生振動， 導致該CCD鏡頭12產生影像畫面模糊而造成量測上的誤 差’尤其當該透鏡裝置11之物鏡採用50倍顯微物鏡進行檢 測時，其量測景深僅約0.9 μπι，當有微小的振動時，常造 成影像無法檢測。 參考圖2，顯示習知DVD讀寫頭之示意圖。該DVD讀寫 頭2係為SONY公司所生產型號為KHM 210 AAA的DVD讀 取頭。該DVD讀寫頭2包括一雷射二極體（Laser Diode)21、一光栅（Grating)22、一分光器23、一準直透鏡 (Collimator Lens)24、一物鏡（Objective lens)25、一 柱狀像 散透鏡（Cylinderical Lens)26、一光感測器（Photo Detector)27及一音圈馬達（Voice Coil)28。 該雷射二極體21係用以發出一光束。該光柵22係用以使 該光束產生繞射。該分光器23包括一極化偏光分離器 (Polarization Beam Splitter, PBS)231及一四分之一波長板 (Quarter Waveplate)232，用以使該光束極化，且改變該光 束之行進方向。該準直透鏡24係用以使該光束形成一準直 光東。該物鏡25之中央具有複數個同心圓狀溝槽，該音圈 馬達28係連接至該物鏡25。該準直光束經過該物鏡25時， 116429.doc 1342387 將可使該準直光束分離成兩部分，在一碟片29上聚焦成適 合DVD或CD光碟片之資料儲存位置的雙焦點，且同時產 • 生一反射光束。 該反射光束穿過該物鏡25、該準直透鏡24、該分光器23 及該柱狀像散透鏡26，而投射至該光感測器27上。該光感 測益27係為一光電二極體（ph〇t〇di〇de IC)，其包括一四象 限光感測器（F〇ur-Quadrant Phot〇 Detect〇r)271，如圖 3所 示該四象限光感測器271依據該反射光束在四個象限 (A、B、C及D四個象限）上的光分佈而輸出一失焦訊號 (Focus Error Signal)。 參考圖4，顯示習知DVD讀寫頭之聚焦原理之示意圖。 該DVD讀寫頭2 (圖2.)之聚焦原理係為像散法。所謂像散 法是指成像時橫向與縱向的成像位置不同，因此造成像點 - 的失真，利用此一像散特性做為量測的依據。當該物鏡25 的垂直焦距與水平焦距不同，則若該碟片29偏離該物鏡25 φ 前焦面位置時，在該四象限光感測器271上之成像光點呈 現橢圓變化（例如第一平面3 1及第三平面3 3 )，當該碟片 29於該物鏡25之正焦位置時，成像光點呈現圓形（如第二 平面32 )。該第一平面3 1係對應圖5a，該第二平面32係對 應圖5b ’該第三平面33係對應圖5c» 參考圖6，顯示習知四象限光感測器之失焦訊號之s曲線 之示意圖。該S曲線係將該圖5 a至5 c經訊號處理而得出。 以圖5a為例’將該第一平面31在A象限及c象限之面積總 和減去在B象限及D象限之面積總和，所得到的值係為正 116429.doc 1342387 值’其即對應該s曲線左側之正值線段。以圖5b為例，將 »玄第一平面3 2在A象限及c象限之面積總和減去在b象限及 D象限之面積總和，所得到的值係為〇，其即對應該s曲線 之原點（零點）。以圖5c為例’將該第三平面33在A象限及 C象限之面積總和減去在B象限及D象限之面積總和所得 到的值係為負值，其即對應該s曲線右側之負值線段。該s 曲線所對應之水平長度L，在CD時係為20 μίΏ，在DVD時 係為7 μπι。 【發明内容】 本發明之主要目的在於提供一種量測系統，其包括：一 透鏡裝置、一影像擷取裝置、一定位平台、一光學感測裝 置及一仏號處理裝置。該影像擷取裝置係透過該透鏡裝置 擷取一物體之影像。該定位平台係用以調整該透鏡裝置之 焦距。該光學感測裝置係用以感測該物體之位置，且發出 一第一信號。該信號處理裝置係接受且處理該第一信號後 發出一第二信號至該定位平台。藉此，可達自動對焦之功 能。 本發明之另一目的在於提供一種光學感測裝置，其包 括.一發光源、一光柵（Grating)、一分光器 '-準直透鏡 (Collimator Lens)、一 反射鏡（Mirror)、一物鏡（〇bjective lens)、一柱狀像散透鏡（Cylinderical Lens)及一光感測器 (Photo Detector)。該發光源係用以發出一光東。該光柵係 用以使該光東產生繞射。該分光器係用以使該光束極化， 且改變該光束之行進方向。該準直透鏡係用以使該光束形 M6429.doc 1342387 成m束。該反射鏡係、用以改變該準直光束之行進方 向。該物鏡之中央具有複數個同心圓狀溝槽，用以將該準 直光束聚;U該物體上。該柱狀像散透鏡係以接受來自該 物體之一反射光束，該反射光束穿過該物鏡、該反射鏡、 該準直透鏡及該分光ϋ。該光感測器係用以感職反射光 束。藉此，可使#該光學感測裝i的量測點十分接近該透 鏡裝置及該影像擷取裝置之量測區，因而可以減少該光學 感測裝置與該透鏡裝置及該影像擷取裝置間之非同軸量測 的誤差。 【實施方式】 參考圖7，顯示本發明之量測系統之較佳實施例之示意 圖。該量測系統4包括一透鏡裝置41、一影像擷取裝置 42、一疋位平台43、一光學感測裝置44及一信號處理裝置 45 ^該透鏡裝置41包括一物鏡，其係為一維陣列透鏡。在 本實把例中物鏡係為十倍物鏡。該影像操取裝置係透過 該透鏡裝置41擷取一物體46(例如一玻璃基板）之影像。在 本實施例中，該影像擷取裝置42係為一CcD鏡頭。該物艘 46係置放於一機台47上。該定位平台43包括一驅動馬達、 一馬達軸控制卡及一平台本體。該定位平台43係用以調整 該透鏡裝置41之焦距。在本實施例中，該定位平台43之精 度可達（Μ μπι，該驅動馬達之型號為5_pHASE driver DFU15 07，該馬達軸控制卡係由ADVANTECH公司所生 產，其型號為PCI-1240U，該平台本體係由KOHZU公司所 生產，其型號為XA07-13。 116429 doc -10· 1342387 忒光學感測裝置44係用以感測該物體46之位置，且發出 一第一信號。該透鏡裝置4 1、該影像擷取裝置42 '該定位 平台4 3及έ哀光學感測裝置44係位於一固定基板4 8上，使得 邊透鏡裝置41與該物體46間隔一適當距離。該信號處理裝 置45接受且處理來自該光學感測裝置44之該第一信號後發 出一第二信號至該定位平台43，以調整該透鏡裝置41之焦 距。 參考圖8，顯示本發明之量測系統之光學感測裝置之較 佳實施例之内部示意圖。該光學感測裝置44包括一發光源 441 ' 一光栅（Grating)442、一分光器443、一準直透鏡 (Collimator Lens)444、一 反射鏡（Mirror)445、一物鏡 (Objective lens)446、一 柱狀像散透鏡（CyHnderical Lens)447、一光感測器（photo Detector)448及一音圈馬達 (Voice Coil)449。 在本實施例中，該發光源441係為一雷射二極體（Laser Diode)，其係用以發出一光束。該光栅442係用以使該光 束產生繞射。該分光器44 3包括一極化偏光分離器 (Polarization Beam Splitter, PBS)443 1 及一四分之一波長板 (Quarter Waveplate)4432，用以使該光束極化，且改變該 光束之行進方向。該準直透鏡444係用以使該光束形成一 準直光束。該反射鏡445係用以改變該準直光束之行進方 向°該物鏡446之中央具有複數個同心圓狀溝槽，該音圈 馬達449係連接至該物鏡446。該準直光束經過該物鏡446 時’將可使該準直光束聚焦至該物體46，且同時產生一反 116429.doc -11 - 1342387 射光束。 該反射光束穿過該物鏡446、該反射鏡445、該準直透鏡 444、該分光器443及該柱狀像散透鏡447 ,而投射至該光 感測器448上。在本實施例中，該光感測器448係為一光電 二極體（Photodiode 1C)，其包括一四象限先感測器（F〇ur_IX. Description of the Invention: [Technical Field] The present invention relates to an optical sensing device and a measuring system including the optical sensing device, which are described in detail as a method for sensing a surface change of an object to be tested An optical sensing device and a metrology system including the optical sensing device. [Prior Art] The TFT-LCD process technology mainly forms a plurality of transistors on a substrate through a semiconductor-like manufacturing technique (coating, exposure, development, etching, etc.). In the process of process inspection, it is generally necessary to use a manual or robotic arm to place the glass substrate on a TFT-LCD measurement system for inspection. Referring to Figure 1, a schematic diagram of a conventional TFT-LCD measurement system is shown. The measurement system 1 includes a lens device 丨1, a CCD lens 丨2, a positioning platform 13, and a signal processing device 14. The lens unit Η includes an objective lens which is a dimensional array lens. The CCD lens 12 captures an image of an object 15 (e.g., the glass substrate) through the lens unit u. The object 15 is placed on the machine table 17. The positioning platform 13 includes a drive motor, a motor shaft control card, and a platform body. The positioning platform 13 is for adjusting the focal length of the lens device 11. The lens device 11, the CCD lens 12 and the positioning platform 13 are disposed on the fixed substrate 16 such that the lens device 11 is spaced apart from the object 15 by an appropriate distance. The signal processing device 14 receives the image data from the CCD lens 12 and compares the image quality of the image data with its focus standard to generate a control signal 'and transmits the control signal to the positioning platform 13' to adjust the lens. The focal length of the device 11. I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I This will waste a lot of time, and there is no standard for the clear standard of image captured in this way. Another disadvantage of the measuring system 1 is that when the object 15 is placed on the machine table 17, if it is subjected to an external excitation, the object 15 will vibrate, resulting in blurring of the image of the CCD lens 12. The error in measurement is caused, especially when the objective lens of the lens device 11 is detected by a 50-fold microscope objective, and the measured depth of field is only about 0.9 μm. When there is a slight vibration, the image is often undetectable. Referring to Figure 2, a schematic diagram of a conventional DVD read/write head is shown. The DVD read/write head 2 is a DVD read head manufactured by SONY Corporation and model number KHM 210 AAA. The DVD read/write head 2 includes a laser diode 21, a grating 22, a beam splitter 23, a collimator lens 24, an objective lens 25, and a A cylindrical astigmatism lens 26, a photo Detector 27, and a voice coil motor 28 (Voice Coil) 28. The laser diode 21 is used to emit a light beam. The grating 22 is used to cause the beam to be diffracted. The beam splitter 23 includes a Polarization Beam Splitter (PBS) 231 and a Quarter Waveplate 232 for polarizing the beam and changing the direction of travel of the beam. The collimating lens 24 is used to form the beam into a collimated light. The objective lens 25 has a plurality of concentric circular grooves in the center thereof, and the voice coil motor 28 is connected to the objective lens 25. When the collimated beam passes through the objective lens 25, 116429.doc 1342387 will separate the collimated beam into two parts, focusing on a disc 29 into a bifocal point suitable for the data storage location of the DVD or CD disc, and simultaneously Produce • Generate a reflected beam. The reflected beam passes through the objective lens 25, the collimator lens 24, the beam splitter 23, and the columnar astigmatic lens 26, and is projected onto the photo sensor 27. The photo-sensing benefit 27 is a photodiode (ICP), which includes a four-quadrant photo sensor (F〇ur-Quadrant Phot〇Detect〇r) 271, as shown in FIG. The four-quadrant light sensor 271 is shown to output a focus error signal according to the light distribution of the reflected light beam in four quadrants (four quadrants A, B, C, and D). Referring to Figure 4, a schematic diagram of the focusing principle of a conventional DVD read/write head is shown. The focusing principle of the DVD head 2 (Fig. 2.) is the astigmatism method. The so-called astigmatism method refers to the difference between the horizontal and vertical imaging positions during imaging, thus causing the distortion of the image point, and using this astigmatism characteristic as the basis for measurement. When the vertical focal length of the objective lens 25 is different from the horizontal focal length, if the disc 29 is offset from the front focal plane position of the objective lens 25 φ, the imaging spot on the four-quadrant light sensor 271 exhibits an elliptical change (for example, the first The plane 3 1 and the third plane 3 3 ), when the disc 29 is at the positive focus position of the objective lens 25, the imaging spot appears circular (such as the second plane 32). The first plane 31 corresponds to FIG. 5a, and the second plane 32 corresponds to FIG. 5b. The third plane 33 corresponds to FIG. 5c». FIG. 6 shows the defocus signal of the conventional four-quadrant light sensor. Schematic diagram of the curve. The S curve is obtained by processing the signals of Figures 5a to 5c. Taking Fig. 5a as an example, 'the first plane 31 is subtracted from the sum of the areas of the A quadrant and the c quadrant minus the area of the B quadrant and the D quadrant, and the obtained value is positive 116429.doc 1342387 value' The positive line segment to the left of the s curve. Taking Fig. 5b as an example, subtracting the sum of the areas of the b quadrant and the D quadrant in the sum of the area of the A first quadrant and the c quadrant, the value obtained is 〇, which corresponds to the s curve. Origin (zero point). Taking Fig. 5c as an example, the value obtained by subtracting the sum of the areas of the B quadrant and the D quadrant of the third plane 33 in the sum of the area of the A quadrant and the C quadrant is a negative value, which is the negative of the right side of the s curve. Value line segment. The horizontal length L corresponding to the s curve is 20 μίΏ for CD and 7 μπι for DVD. SUMMARY OF THE INVENTION A primary object of the present invention is to provide a measurement system including: a lens device, an image capture device, a positioning platform, an optical sensing device, and an nickname processing device. The image capturing device captures an image of an object through the lens device. The positioning platform is used to adjust the focal length of the lens device. The optical sensing device is configured to sense the position of the object and emit a first signal. The signal processing device receives and processes the first signal and sends a second signal to the positioning platform. Thereby, the function of autofocus can be achieved. Another object of the present invention is to provide an optical sensing device including: a light source, a grating, a beam splitter'-collimator lens, a mirror, an objective lens ( 〇bjective lens), a cylindrical astigmatism lens (Cylinderical Lens) and a photo sensor (Photo Detector). The light source is used to emit a light. The grating is used to cause the light to be diffracted. The beam splitter is used to polarize the beam and change the direction of travel of the beam. The collimating lens is used to make the beam shape M6429.doc 1342387 into a bundle. The mirror is configured to change the direction of travel of the collimated beam. The center of the objective lens has a plurality of concentric circular grooves for collecting the collimated beam; U on the object. The cylindrical astigmatic lens is adapted to receive a reflected beam from one of the objects, the reflected beam passing through the objective lens, the mirror, the collimating lens and the beam splitter. The light sensor is used to sense the reflected beam. Thereby, the measuring point of the optical sensing device i can be very close to the measuring device of the lens device and the image capturing device, thereby reducing the optical sensing device, the lens device and the image capturing device. Non-coaxial measurement error between. [Embodiment] Referring to Fig. 7, there is shown a schematic view of a preferred embodiment of the measuring system of the present invention. The measuring system 4 includes a lens device 41, an image capturing device 42, a clamping platform 43, an optical sensing device 44, and a signal processing device 45. The lens device 41 includes an objective lens, which is a one-dimensional array. lens. In this example, the objective lens is a tenfold objective lens. The image capture device captures an image of an object 46 (e.g., a glass substrate) through the lens device 41. In this embodiment, the image capturing device 42 is a CcD lens. The boat 46 is placed on a machine base 47. The positioning platform 43 includes a drive motor, a motor shaft control card, and a platform body. The positioning platform 43 is for adjusting the focal length of the lens unit 41. In this embodiment, the positioning platform 43 has an accuracy of (Μ μπι, the model of the driving motor is 5_pHASE driver DFU15 07, the motor shaft control card is produced by ADVANTECH, and its model is PCI-1240U, the platform The system is manufactured by KOHZU Co., Ltd., and its model number is XA07-13. 116429 doc -10· 1342387 The optical sensing device 44 is used to sense the position of the object 46 and emit a first signal. The lens device 4 1 The image capturing device 42 ′′ and the 光学 光学 optical sensing device 44 are located on a fixed substrate 48 such that the side lens device 41 is spaced apart from the object 46 by an appropriate distance. The signal processing device 45 accepts And processing the first signal from the optical sensing device 44 to send a second signal to the positioning platform 43 to adjust the focal length of the lens device 41. Referring to Figure 8, the optical sensing of the measuring system of the present invention is shown. An internal schematic view of a preferred embodiment of the device. The optical sensing device 44 includes a light source 441', a grating 442, a beam splitter 443, a collimator lens 444, and a mirror (Mirr). Or) 445, an objective lens 446, a Cylindrical Lens 447, a photo Detector 448, and a Voice Coil 449. In this embodiment The illuminating source 441 is a laser diode for emitting a light beam. The grating 442 is for diffracting the light beam. The beam splitter 44 3 includes a polarization polarization separation. Polarization Beam Splitter (PBS) 443 1 and a Quarter Waveplate 4432 are used to polarize the beam and change the direction of travel of the beam. The collimating lens 444 is used to The beam forms a collimated beam. The mirror 445 is adapted to change the direction of travel of the collimated beam. The center of the objective lens 446 has a plurality of concentric circular grooves, and the voice coil motor 449 is coupled to the objective lens 446. When the collimated beam passes through the objective 446, 'the collimated beam will be focused to the object 46, and at the same time an inverted 116429.doc -11 - 1342387 beam is generated. The reflected beam passes through the objective 446, the mirror 445 The collimating lens 444, the beam splitter 443, and the The astigmatic lens 447 is projected onto the photo sensor 448. In the embodiment, the photo sensor 448 is a photodiode (Photodiode 1C), which includes a four-quadrant first sensor. (F〇ur_
Quadrant Photo Detector)(與圖3之該四象限光感測器271相 同）’該四象限光感測器依據該反射光束在四個象限、 B、C及D四個象限）上的光分佈而輸出一失焦訊號（F〇cus i Error Signal)(即該第一信號）。 參考圖9，顯示本發明之量測系統之光學感測裝置，之較 佳實施例之立體組合示意圖。請同時參考圖8及圖9，該光 學感測裝置44包括一本體外殼5〇及一L形管5 1。該本體外 殼50用以容置該發光源441、該光柵442、該分光器443、 該準直透鏡444、該柱狀像散透鏡447及該光感測器448。 該L形管51係為一中空管體，其具有一第一端5U、一轉折 φ 處512及一第二端513。該第一端511係連接至該本體外殼 50 ’該反射鏡445係位於該轉折處5 12，該物鏡446及該音 圈馬達449係位於該第二端5 13。 請再參考圓9，該量測系統4更包括一固定架52、一微調 平台53及一轉接板54。該光學感測裝置44之本體外殼50係 透過該轉接板54而固設於該微調平台53上。在本實施例 中’該微調平台5 3係為一手動微調平台。該微調平台5 3係 固設於該固定架52上，該囡定架52係囡設於該固定基板48 II6429 doc 4 再參考圖7，在該量測系統4中，由於該光學感測裝置44 之特殊設計，可使得該光學感測裝置44的量測點十分接近 該透鏡裝置41及該影像擷取裝置42之量測區，因而可以減 少該光學感測裝置44與該透鏡裝置41及該影像擷取裝置42 間之非同軸量測的誤差。 該量測系統4之作動方式如下。首先，將該物體46置放 於該機台47上。接著，驅動該定位平台43，使得該影像擷 取裝置42所接收到的影像達到最清晰的狀態。接著，以手 動方式調整該光學感測裝置44之上下位置，使該光學感測 裝置44與該物體46間之距離恰好位於S曲線之線性區域的 原點（零點）上《調整完成後將該光學感測裝置44固定住。 接著，即可進行該物體46的掃瞄量測，在掃瞄量測過程 中’經由該光學感測裝置44可量測出該物體46表面高度之 變化’而且將該高度變化值即時地回授至該信號處理裝置 45，該信號處理裝置45根據該高度變化值驅動該定位平台 43 ’以調整該透鏡裝置41之焦距，而使該量測系統4完成 自動對焦。 以下是該量測系統4之相關實驗及結果。 參考圖1 0，顯示本發明光學感測裝置之S曲線之實際量 測結果。該S曲線的量測方式如下，首先將該光學感測裝 置44從該微調平台53拆下後固定至一精密線性馬達平臺 上。接著，將一測試用反射鏡固定在該光學感測裝置44下 方。接著，再利用該精密線性馬達推動該光學感測裝置44 至距離該測試用反射鏡適當位置。之後每次移動丨μηι，到 U6429.doc ,, 1342387 達定位時，觸發一 A/D資料擷取卡，以讀取該光學感測裝 置44的輪出訊號（即失焦訊號）與平臺位移值。如此，可以 得到平X位置與4光學感測裝置44之失焦電壓訊號的對應 關係，此關係便是S曲線，如圖丨〇所示。要注意的是，在 本發明中，所應用之S曲線之區段僅為曲線6〇之線性區 段。 參考圖11，顯示本發明光學感測裝置實際量測一 TFT_ LCD之結果。由圖中可看出，本發明可應用於的 高度量測。 參考圖12，顯示本發明光學感測裝置所實際量測之十字 形樣版。該十字形樣版經a_step儀器量測後，得到其膜厚 高度為0.2649 Mm。本發明之該光學感測裝置料採用相同 於α-step儀器的量測掃描方向（圖中箭頭方向），將量到的 電壓值藉由S曲線斜率值轉換成位移單位後，得到高度值 為0.274 μηι，誤差量約3%。因此可知該光學感測裝置軔的 量測精度相仿於習知精密量測儀器。 參考圖13’顯示本發明光學感測裝置之動態測試結果。 以PhySlk InStrumente(PI)公司所生產的三軸奈米定位平台 (型號為PI-762.3L)的X轴方向做為激振源，在χ軸方向上 黏貼一反射片，並將該光學感測裝置44置於該反射片上 方。利用-函數產生器輸人-頻率丨.5 ΚΗζ，位移為5 _ 之正弦訊號至該三軸奈米定位丨台之乂轴@，摘取該光學 感測裝置44之輪出訊號如圖13所示。因此，可證明該光二 感測裝置44之量測速度至少每秒達3 〇 mm。 116429 doc 1342387 惟上述實施例僅為說明本發明之原理及其功效，而非用 以限制本發明。因此，習於此技術之人士可在不違背本發 明之精神對上述實施例進行修改及變化。本發明之權利範 圍應如後述之申請專利範圍所列。 【圖式簡單說明】 圖1顯示習知TFT-LCD量測系統之示意圖； 圖2顯示習知DVD讀寫頭之示意圖； 圖3顯示習知光感測器之四象限光感測器之示意圖； 圖4顯示習知DVD讀寫頭之聚焦原理之示意圖； 圖5a顯示習知四象限光感測器上第一種成像狀態； 圖5b顯示習知四象限光感測器上第二種成像狀態； 圖5c顯示習知四象限光感測器上第三種成像狀態； 圖6顯示習知四象限光感測器之失焦訊號之§曲線之示意 圖； 圖7顯示本發明之量測系統之較佳實施例之示意圖； 圖8頭示本發明之量測系統之光學感測裝置之較佳實施 例之内部示意圖； 圖9 ”肩示本發明之量測系統之光學感測裝置之較佳實施 例之立體組合示意圖； 圖10顯示本發明央聲咸測& ¥ 4 h /3尤子U州裝置之S曲線之實際量測結 果； ' 圖11顯示本發明光學感測裝w者 于d J衣置只際$測—tft lcd之結 果； 圖12顯示本發明光學感測裝置所實際量測之十字形樣 116429.doc 1342387 版；及 圖13顯示本發明光學感測裝置之動態測試結果。 【主要元件符號說明】Quadrant Photo Detector) (same as the four-quadrant photo sensor 271 of FIG. 3) 'The four-quadrant photosensor is based on the light distribution of the reflected beam in four quadrants, B, C, and D quadrants) A defocus signal (F〇cus i Error Signal) is output (ie, the first signal). Referring to Figure 9, there is shown a perspective view of a preferred embodiment of an optical sensing device of the metrology system of the present invention. Referring to FIG. 8 and FIG. 9, the optical sensing device 44 includes a body casing 5〇 and an L-shaped tube 51. The outer casing 50 accommodates the illumination source 441, the grating 442, the beam splitter 443, the collimating lens 444, the columnar astigmatic lens 447, and the photo sensor 448. The L-shaped tube 51 is a hollow tube body having a first end 5U, a turning φ 512 and a second end 513. The first end 511 is coupled to the body housing 50'. The mirror 445 is located at the turning point 51, and the objective lens 446 and the voice coil motor 449 are located at the second end 513. Referring to the circle 9, the measuring system 4 further includes a fixing frame 52, a fine adjustment platform 53, and an adapter plate 54. The body casing 50 of the optical sensing device 44 is fixed to the fine adjustment platform 53 through the adapter plate 54. In this embodiment, the fine tuning platform 53 is a manual fine tuning platform. The fine adjustment platform 53 is fixed on the fixing frame 52, and the fixing frame 52 is disposed on the fixed substrate 48 II6429 doc 4 and then refer to FIG. 7 , in the measuring system 4 , due to the optical sensing device The special design of the optical sensing device 44 is such that the measuring point of the optical sensing device 44 is very close to the measuring area of the lens device 41 and the image capturing device 42, thereby reducing the optical sensing device 44 and the lens device 41. The non-coaxial measurement error between the image capture devices 42. The operation of the measuring system 4 is as follows. First, the object 46 is placed on the machine table 47. Then, the positioning platform 43 is driven so that the image received by the image capturing device 42 reaches the clearest state. Then, the upper and lower positions of the optical sensing device 44 are manually adjusted so that the distance between the optical sensing device 44 and the object 46 is exactly at the origin (zero point) of the linear region of the S curve. The optical sensing device 44 is fixed. Then, the scanning measurement of the object 46 can be performed, and the change in the surface height of the object 46 can be measured through the optical sensing device 44 during the scanning measurement and the height change value is immediately returned. The signal processing device 45 is driven to drive the positioning platform 43' to adjust the focal length of the lens device 41 according to the height change value, so that the measurement system 4 completes the autofocus. The following are related experiments and results of the measurement system 4. Referring to Figure 10, the actual measurement results of the S-curve of the optical sensing device of the present invention are shown. The S-curve is measured in the following manner. First, the optical sensing device 44 is detached from the fine adjustment platform 53 and fixed to a precision linear motor platform. Next, a test mirror is attached below the optical sensing device 44. The precision linear motor is then used to push the optical sensing device 44 to the appropriate position from the test mirror. After each movement of 丨μηι, U6429.doc, and 1342387, an A/D data capture card is triggered to read the round-out signal (ie, the out-of-focus signal) and the platform displacement of the optical sensing device 44. value. Thus, the corresponding relationship between the flat X position and the out-of-focus voltage signal of the 4 optical sensing device 44 can be obtained, and the relationship is the S curve, as shown in FIG. It is to be noted that in the present invention, the section of the S curve applied is only a linear section of the curve 6〇. Referring to Figure 11, the result of actually measuring a TFT_LCD of the optical sensing device of the present invention is shown. As can be seen from the figure, the present invention is applicable to high-metric measurements. Referring to Figure 12, a cross-shaped pattern actually measured by the optical sensing device of the present invention is shown. The cross-shaped plate was measured by a_step instrument to obtain a film thickness of 0.2649 Mm. The optical sensing device of the present invention uses the same scanning direction as the α-step instrument (the direction of the arrow in the figure), and converts the measured voltage value into a displacement unit by the slope value of the S curve to obtain a height value. 0.274 μηι, the error is about 3%. Therefore, it can be seen that the measurement accuracy of the optical sensing device is similar to that of the conventional precision measuring instrument. The dynamic test results of the optical sensing device of the present invention are shown with reference to Figure 13'. The X-axis direction of the three-axis nano positioning platform (model PI-762.3L) manufactured by PhySlk InStrumente (PI) was used as the excitation source, a reflection sheet was adhered in the direction of the x-axis, and the optical sensing was performed. A device 44 is placed over the reflective sheet. Using the -function generator to input the human-frequency 丨.5 ΚΗζ, the sinusoidal signal with a displacement of 5 _ to the axis of the three-axis nanopositioning platform, and the wheel-out signal of the optical sensing device 44 is as shown in FIG. Shown. Therefore, it can be demonstrated that the measuring speed of the optical sensing device 44 is at least 3 每秒 mm per second. 116429 doc 1342387 The above examples are merely illustrative of the principles of the invention and its utility, and are not intended to limit the invention. Therefore, those skilled in the art can make modifications and changes to the above embodiments without departing from the spirit of the invention. The scope of the invention should be as set forth in the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic view showing a conventional TFT-LCD measuring system; FIG. 2 is a schematic view showing a conventional DVD reading head; FIG. 3 is a schematic view showing a four-quadrant optical sensor of a conventional photosensor; 4 shows a schematic diagram of the focusing principle of a conventional DVD read/write head; FIG. 5a shows a first imaging state on a conventional four-quadrant light sensor; FIG. 5b shows a second imaging state on a conventional four-quadrant light sensor; Figure 5c shows a third imaging state on a conventional four-quadrant light sensor; Figure 6 shows a schematic diagram of a defocusing signal of a conventional four-quadrant light sensor; Figure 7 shows a comparison of the measurement system of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 8 is a schematic diagram showing the internal structure of a preferred embodiment of the optical sensing device of the measuring system of the present invention; FIG. 9 is a schematic view showing the preferred embodiment of the optical sensing device of the measuring system of the present invention. FIG. 10 shows the actual measurement result of the S curve of the device of the present invention, and the optical curve of the present invention is shown in FIG. J clothing is only the result of $ measured - tft lcd; Figure 12 shows the hair Cross-like version of the optical sensing means sensing the actual amount of 116429.doc 1342387; and Figure 13 shows the dynamic test results of the optical sensing apparatus of the present invention, [REFERENCE SIGNS LIST principal elements.
1 習知量測系統 2 習知DVD讀寫頭 4 本發明之量測系統 11 透鏡裝置 12 CCD鏡頭 13 定位平台 14 信號處理裝置 15 物體 16 固定基板 17 機台 21 雷射二極體 22 光栅 23 分光器 24 準直透鏡 25 物鏡 26 柱狀像散透鏡 27 光感測器 28 音圈馬達 29 碟片 31 第一半面 32 第二平面 116429.doc .16- 13423871 conventional measuring system 2 conventional DVD reading head 4 measuring system 11 of the invention lens device 12 CCD lens 13 positioning platform 14 signal processing device 15 object 16 fixed substrate 17 machine 21 laser diode 22 grating 23 Beam splitter 24 Collimating lens 25 Objective lens 26 Columnar astigmatic lens 27 Light sensor 28 Voice coil motor 29 Disc 31 First half 32 Second plane 116429.doc .16- 1342387
33 第三平面 41 透鏡裝置 42 影像擷取裝置 43 定位平台 44 光學感測裝置 45 信號處理裝置 46 物體 47 機台 48 固定基板 50 本體外殼 51 L形管 52 固定架 53 微調平台 54 轉接板 60 曲線 231 極化偏光分離器 232 四分之一波長板 271 四象限光感測器 441 發光源 442 光柵 443 分光器 444 準直透鏡 445 反射鏡 446 物鏡 116429.doc •17 1342387 447 448 449 511 512 513 4431 4432 柱狀像散透鏡 光感測器 音圈馬達 L形管第一端 L形管轉折處 L形管第二端 極化偏光分離器 四分之一波長板 116429.doc -18-33 Third plane 41 Lens device 42 Image capturing device 43 Positioning platform 44 Optical sensing device 45 Signal processing device 46 Object 47 Machine 48 Fixed substrate 50 Body housing 51 L-shaped tube 52 Fixing frame 53 Fine adjustment platform 54 Adapter plate 60 Curve 231 Polarization Polarizer 232 Quarter Wave Plate 271 Four-Quad Light Sensor 441 Light Source 442 Grating 443 Beam Splitter 444 Collimating Lens 445 Mirror 446 Objective 116626.doc • 17 1342387 447 448 449 511 512 513 4431 4432 Columnar astigmatic lens light sensor voice coil motor L-shaped tube first end L-shaped tube turning point L-shaped tube second end polarized polarization splitter quarter-wave plate 116429.doc -18-