200928347 九、發明說明： 【發明所屬之技術領域】 本發明是有關於一種測量光學旋轉角之裝置，特別是 有關於一種可測量光學旋轉角之裝置。 【先前技術】 Ο 〇 目前’實驗室常用之旋光性物質，例如：1/2λ波片 或生化物質右旋葡萄糖等，其係具有光學旋轉角度之特 性’即當線性偏振光通過旋光性物質時，線性偏振光會 產生旋轉的現象。此類物質時常利用於光電、食品、醫 藥、化工等需要準確的決定其光學旋轉角，以即G掌握 物質的存在狀態、濃度改變或其它變化。 習知相關量測系統有準確度與解析度受 消光品質，支樓偏振片之平台有機械上限制，及 容易受環境熱擾動，使得量測之次數須多等缺失，此外 也有採用強度正比與光學旋轉角之方式，但低強度時， 則易受雜訊干擾，解析度亦會受限。 h i — f知係利用昂貴的Zeeman雷射當光源及利用 有鑑於習知技藝之各項問題，為了能夠兼顧 之，本發明人基於多年研究開發與諸實出 -種測量光學旋轉角之裝置，以作為改點3 現方式與依據。 音上C缺點之實 5 200928347 【發明内容】 有鑑於此，本發明之目的就是在提供一種測量光學 旋轉角之裝置，以解決量測光學旋轉角所產生之成本、 精確度及複雜度等問題。 根據本發明之目的，本發明係揭露一種測量光學旋 轉角之裝置，其包括一雷射模組、一電光調變模組、一 旋光物質、一檢振片、一光檢測模組及一鎖相放大器。 雷射模組係用以發出一雷射光，雷射光係透過一偏振片 〇 限疋雷射光之偏振方向以產生一第一雷射光，電光調變 模組係用以調變第一雷射光之相位以產生一第二雷射 光’第二雷射光係通過一波片以更改第二雷射光之偏振 狀態’旋光物質係使已更改偏振狀態之第二雷射光產生 一旋轉角’檢振片係用以調整已更改偏振狀態之第二雷 射光之光強度，光檢測模組係檢測已更改偏振狀態之第 二雷射光之光強度以產生一訊號，鎖相放大器係接收訊 號並偵測訊號之相位傳輸與一處理模組以計算該旋轉角 之度數。BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a device for measuring an optical rotation angle, and more particularly to a device for measuring an optical rotation angle. [Prior Art] Ο 〇 Currently, the optically active substances commonly used in laboratories, such as 1/2λ wave plate or biochemical dextrose, which have the characteristics of optical rotation angle, that is, when linearly polarized light passes through an optically active substance. Linearly polarized light produces a phenomenon of rotation. Such materials are often used in optoelectronics, food, medicine, chemicals, etc. to accurately determine their optical rotation angle, that is, G grasps the existence state, concentration change or other changes of the substance. The correlation measurement system has the accuracy and resolution of the extinction quality, the platform of the polarizer of the branch building has mechanical limitations, and is susceptible to environmental heat disturbance, so that the number of measurement times must be missing, and the intensity is proportional to The mode of optical rotation angle, but at low intensity, it is susceptible to noise interference and the resolution is limited. Hi-f knows that the expensive Zeeman laser is used as a light source and the use of the various problems in view of the prior art, in order to be able to take care of it, the inventors have based on years of research and development and various devices for measuring the optical rotation angle. Take the change as point 3 and the basis. In view of the above, the object of the present invention is to provide a device for measuring an optical rotation angle to solve the problems of cost, accuracy and complexity of measuring an optical rotation angle. . In accordance with the purpose of the present invention, an apparatus for measuring an optical rotation angle includes a laser module, an electro-optical modulation module, an optically active substance, a vibration detecting piece, a light detecting module, and a lock. Phase amplifier. The laser module is configured to emit a laser light, and the laser light is limited to the polarization direction of the laser light through a polarizing plate to generate a first laser light, and the electro-optical modulation module is used to modulate the first laser light. Phase to generate a second laser light. The second laser light passes through a wave plate to modify the polarization state of the second laser light. The optically active material causes the second laser light of the changed polarization state to generate a rotation angle. The light detecting module detects the light intensity of the second laser light with the changed polarization state, and the light detecting module detects the light intensity of the second laser light with the changed polarization state to generate a signal, and the lock-in amplifier receives the signal and detects the signal. The phase is transmitted with a processing module to calculate the degree of the rotation angle.
Q 兹為使貴審查委員對本發明之技術特徵及所達到 之功效有更進一步之瞭解與認識，謹佐以較佳之實施例 及配合詳細之說明如後。 【實施方式】 以下將參照相關圖示，說明依本發明較佳實施例之 測量光學旋轉角之裝置，為使便於理解，下述實施例中之 相同元件係以相同之符號標示來說明。 請參閱第1圖，其係為本發明之測量光學旋轉角之 200928347 裝置之實施例示意圖。圖中，測量光學旋轉角之裝置包 ’ 含包括一雷射模組11、一電光調變模組12、一旋光物質 - 13、一檢振片14、一光檢測模組15及一鎖相放大器16。 雷射模組係用以發出一雷射光111，此雷射光111係為一 氦氖雷射（He-Ne Laser)，雷射光係透過一偏振片19限定 雷射光之偏振方向以產生一第一雷射光191，第一雷射光 191係為具有單一偏振方向之雷射光。電光調變模組12 係用以調變第一雷射光之相位以產生一第二雷射光，此 電光調變模組12是以一函數產生器所提供之鋸齒波形訊 〇 號來調製的。第二雷射光係通過一波片121以更改第二 雷射光之偏振狀態，此波片121係可為一 1/4 λ波片，其 中，1/4 λ波片係使該第二雷射光產生一橢圓偏振光（具兩 圓偏振光分量，兩分量間有頻率差）。旋光物質13係使已 更改偏振狀態之第一雷射光產生一旋轉角，此旋光物質 13係可為一 1/2λ波片及一葡萄糖溶液等可使光束旋轉 之物質，檢振片14係用以調整已更改偏振狀態之第二雷 射光之光強度，其中，測量光學旋轉角之裝置更可包含 ❹一帶通濾波器18以濾過訊號之雜訊。光檢測模組15係 檢測已更改偏振狀態之第二雷射光之光強度以產生一訊 號，鎖相放大器16係接收訊號並偵測訊號之相位傳輪與 一處理模組17以計算該旋轉角之度數，此量測光學旋轉 角之裝置係利用鎖相放大器16之高精度與靈敏度，來使 得電光調變模組12之對位誤差降到最低，以確保非線性 誤差很小。此訊號之相位係與旋轉角線性相關，例如： 相位變化越大，則旋轉角越大。鎖相放大器16係用以準 確偵測該訊號之交流振幅，以降低該電光調變模組12之 對位誤差，當無樣本時鎖相放大器之理論值為零。此鎖 7 200928347 相放大器16係為一二相型數位訊號處理鎖相放大器。 再者，本裝置所輸出之電場，表示如下方程式： ❹Q For a better understanding and understanding of the technical features and the efficacies of the present invention, the preferred embodiments and the detailed description are as follows. [Embodiment] Hereinafter, a device for measuring an optical rotation angle according to a preferred embodiment of the present invention will be described with reference to the accompanying drawings. For the sake of understanding, the same components in the following embodiments are denoted by the same reference numerals. Please refer to Fig. 1, which is a schematic view of an embodiment of the apparatus for measuring an optical rotation angle of 200928347 of the present invention. In the figure, the device for measuring the optical rotation angle includes a laser module 11, an electro-optical modulation module 12, an optically active substance-13, a vibration detecting sheet 14, a light detecting module 15, and a phase lock. Amplifier 16. The laser module is used to emit a laser light 111, which is a He-Ne Laser, and the laser light defines a polarization direction of the laser light through a polarizing plate 19 to generate a first The laser light 191, the first laser light 191 is a laser light having a single polarization direction. The electro-optical modulation module 12 is configured to modulate the phase of the first laser light to generate a second laser beam. The electro-optical modulation module 12 is modulated by a sawtooth waveform signal provided by a function generator. The second laser light passes through a wave plate 121 to change the polarization state of the second laser light. The wave plate 121 can be a 1/4 λ wave plate, wherein the 1/4 λ wave plate makes the second laser light An elliptically polarized light (having two circularly polarized light components with a frequency difference between the two components) is produced. The optically active substance 13 generates a rotation angle of the first laser light having a changed polarization state, and the optically active substance 13 is a substance such as a 1/2λ wave plate and a glucose solution that can rotate the light beam, and the vibration detecting sheet 14 is used. To adjust the intensity of the light of the second laser light having changed the polarization state, wherein the means for measuring the optical rotation angle may further include a bandpass filter 18 to filter the noise of the signal. The light detecting module 15 detects the light intensity of the second laser light having changed the polarization state to generate a signal, and the lock-in amplifier 16 receives the signal and detects the phase of the signal and a processing module 17 to calculate the rotation angle. The degree, the device for measuring the optical rotation angle utilizes the high precision and sensitivity of the lock-in amplifier 16 to minimize the alignment error of the electro-optic modulation module 12 to ensure that the nonlinear error is small. The phase of this signal is linearly related to the angle of rotation, for example: The larger the phase change, the larger the angle of rotation. The lock-in amplifier 16 is used to accurately detect the AC amplitude of the signal to reduce the alignment error of the electro-optic modulation module 12. When there is no sample, the theoretical value of the lock-in amplifier is zero. This lock 7 200928347 phase amplifier 16 is a two-phase digital signal processing lock-in amplifier. Furthermore, the electric field output by the device represents the following equation:
馬=(450).50(900,^).^(450).¾ * 4 Λ "" _ Ί-j 1 + ϊΊ 1 0 cosy sm^ 2 2 0 0_ 一 cos 尸 1+ϊ 1-ΐ L 2 2 J -4 - '1 Γ e 2 0 2 2 '0 ' .at _ 0 1 1 .2 2. ·ε〇· β 方程式（一） 此時，尽是輸入電場的振幅，4>°)時表示檢振片14 與X軸成平行的瓊斯矩陣，办表示旋光物質13的瓊斯矩 陣，γ是此旋光物質π的光學旋轉角度，再者，⑷4巧表示 四分之一波片，其快軸與X軸成45。的瓊斯矩陣，£〇(9〇。，叫 表示一個以《頻率鋸齒波驅動的電光調變模組12及其主 轴平行y軸的瓊斯矩陣，p(45t))表示一個偏振片19與X轴 ❹ 成45°的瓊斯矩陣。 因此’光檢測模組15檢測得的穿透輸出光強度可由 下方程式表示： 方程式（二） &代表輸出光強的交流分量，4為代表輸出光強的直 流分量等於拉/4，拉為輸入光的強度，Θ代表輸出光強的 8 200928347 相位，其值為-2 τ*。從方程式（二），利用一個二相型數位 訊號處理的鎖相放大器16以鎖住輸出光強交流分量^在 參考頻率《下的相位大小Θ，藉由上述二公式，旋光物 13的光學旋轉角度能由以下方程式表示之： γHorse=(450).50(900,^).^(450).3⁄4 * 4 Λ "" _ Ί-j 1 + ϊΊ 1 0 cosy sm^ 2 2 0 0_ a COS corpse 1+ϊ 1- ΐ L 2 2 J -4 - '1 Γ e 2 0 2 2 '0 ' .at _ 0 1 1 .2 2. · ε〇· β Equation (1) At this point, the amplitude of the input electric field is 4,gt; °) represents a Jones matrix in which the oscillating sheet 14 is parallel to the X-axis, a Jones matrix representing the optically active substance 13, γ is the optical rotation angle of the optically active substance π, and (4) 4 represents a quarter-wave plate, Its fast axis is 45 with the X axis. The Jones matrix, 〇 (9〇., denotes a Jones matrix with the frequency sawtooth-driven electro-optical modulation module 12 and its spindle parallel y-axis, p(45t)) represents a polarizer 19 and the X-axis ❹ A 45° Jones matrix. Therefore, the intensity of the transmitted output light detected by the light detecting module 15 can be expressed by the following formula: Equation (2) & represents the AC component of the output light intensity, and 4 represents the DC component of the output light intensity equal to the pull/4, which is The intensity of the input light, Θ represents the phase of the output light of 200928347, which is -2 τ*. From equation (2), a lock-in amplifier 16 processed by a two-phase type digital signal is used to lock the output light intensity AC component ^ at the reference frequency "the phase size Θ, by the above two formula, the optical rotation of the optical object 13 The angle can be expressed by the following equation: γ
A 方程式（三） 藉由方程式（一）、方程式（二）及方程式（三）， 〇 可计算出光學旋轉角之度數且可達到不受環境擾動 響’乞少的光學元件’外差頻率可調整，信號處理容易/ 及具尚線性度#測等特性，並以簡單 光J旋轉角之結果’且避免使用昂㈣ζ_上得以 到節省成本之效果。 以上所述僅為舉例性，而非為限帝⑽者。任 離本發明之精神與料對其 更，均應包含於後附之巾請專利_中。 改或變 〇 【圖式簡單說明】 第1圖=本發明之測量光學旋轉角之裝置之實施例示 200928347 【主要元件符號說明】 11 :雷射模組； 111 :雷射光； 12 :電光調變模組； 121 :波片； 122 :第二雷射光； 13 :旋光物質； 14 ·檢振片， 15 :光檢測模組； © 151 :訊號； 16 :鎖相放大器； 17 :處理單元； 18 :帶通濾波器； 19 :偏振片；以及 191 :第一雷射光。A Equation (3) By Equation (1), Equation (2), and Equation (3), 〇 can calculate the degree of optical rotation angle and can achieve an optical component that is immune to environmental disturbances. Adjustment, signal processing is easy / and has a linearity degree # measured characteristics, and the result of a simple light J rotation angle 'and avoid the use of Ang (four) ζ _ to achieve cost-saving effect. The above description is only for the sake of example, not for the limited (10). Any of the spirit and materials of the present invention should be included in the attached patent application. Change or change [Simplified description of the drawing] Fig. 1 = Embodiment of the apparatus for measuring optical rotation angle of the present invention 200928347 [Description of main components] 11: Laser module; 111: Laser light; 12: Electro-optical modulation Module; 121: wave plate; 122: second laser light; 13: optically active material; 14 · vibration detecting piece, 15: light detecting module; © 151: signal; 16: lock-in amplifier; 17: processing unit; : band pass filter; 19: polarizer; and 191: first laser light.