本研究成功開發出一套創新的剪切干涉式波前感測器量測技術，可藉由量測波前變化，進行光學成像系統組裝程序中，透鏡元件於三維空間的位置對位檢測與校正，除可克服業界常用的雷射準直儀偏心檢測系統無法進行透鏡元件之間光軸向位置對位與校正之問題，有效提升光學系統組裝定位之準確度，同時本技術亦能直接求得待測透鏡或光學成像系統的像差、點擴展函數(Point Spread Function, PSF)及調制轉換函數(Modulation Transfer Function, MTF)等成像性能資訊，大幅縮短光學成像系統MTF量測時間。
本研究所提出的剪切干涉式波前感測器量測技術包含光學模組及軟體分析模組兩部分。光學模組由光源、空間濾波器、感光耦合元件(CCD)與自行設計的二進制棋盤光柵元件所組成。當一雷射光束經空間濾波器後形成準直的平面波光束，而後通過待測透鏡或光學成像系統，帶有透鏡或光學成像系統波前資訊的光束將通過由光柵與CCD的組合建構出的四波橫向剪切干涉光路，待測透鏡或光學成像系統的波前資訊經光柵後形成繞射及干涉，最後干涉斑紋影像將由CCD所接收，接著以自行開發的「波前解相演算單元」及「成像性能分析演算單元」，對CCD所拍攝的干涉影像進行分析，「波前解相演算單元」可以從干涉影像中提取出光學系統的待測資訊，由所計算出的波前資訊與光學系統中透鏡擺放位置偏差的對應關係，便能夠進行光學系統中各片透鏡於三維空間的位置對位檢測與校正。而「成像性能分析演算單元」則負責將所量測到的波前資訊進行影像分析，而後計算出待測光學系統的Zernike像差、PSF、MTF等成像性能資訊。
為了驗證所提出之剪切干涉式波前感測器的可行性及量測特性，本研究進行了數值分析及多項驗證實驗。首先，為確認本研究設計的二進制棋盤光柵的設計參數無誤，實驗以光功率計對二進制棋盤光柵進行各繞射階光強效率驗證，同時以數值分析及實驗確認二進制棋盤光柵所產生的非(±1,±1)階繞射光以及泰伯現象對於波前影像量測結果的影響。此外，為驗證波前量測的準確性，本研究以不同規格的商用標準透鏡進行波前量測實驗，並將量測結果與理論值相比較。由實驗結果可知，本套剪切干涉式波前感測器的量測結果與理想球面透鏡波前理論的平均誤差量約為 2.59%。再者，為驗證本套剪切干涉式波前感測器的光學系統校正能力，我們對兩片標準透鏡所組成的共焦系統進行對位檢測實驗，於實驗中藉由改變透鏡於三維空間的相對位置，同時確認所測得的相對應波前資訊，實驗結果驗證我們可成功藉由量得的波前資訊來回推透鏡組裝對位時的空間位置是否存在誤差。最後，藉由將剪切干涉式波前感測器測得的波前資訊輸入本研究所開發的「成像性能分析演算單元」後，即可成功求得待測光學系統的Zernike像差、PSF及MTF等成像性能資訊。由上述實驗證明本量測技術具備準確的波前量測與光學成像系統影像品質分析能力，能針對光學成像系統進行透鏡組裝的位置對位檢測與校正，同時直接提供其光學影像品質分析數據，未來應能廣泛運用於各光學系統的組裝產線及成像性能量測或驗證等場合中。

In this study, a novel shearing interferometer-type wave-front sensor is successfully developed. By measuring wave-front variation, the three-dimensional position of lens components can be detected and corrected during the assembly process of optical imaging systems. In addition to overcoming the problem of industry standard collimator eccentricity detection systems being unable to align and correct the optical axis position between lenses, this technique can also directly obtain the phase-contrast, the point spread function (PSF), modulation transfer function (MTF) and other imaging performance information of lens or optical imaging systems, thus effectively improving the accuracy of optical system assembly and positioning as well as significantly reducing the MTF measurement times.
The proposed system is composed of an optical module and a software analysis module. The optical module consists of a light source, spatial filter, CCD camera and a self-designed binary checkerboard grating. When the laser beam passes through the spatial filter, a collimated plane wave beam is formed, which then passes through the lens or optical imaging system under test. This beam carrying the lens or optical imaging system wave-front information next passes through the four-wave shear interference optical configuration assembled from the grating and CCD, where the wave-front forms diffraction and interference after passing through the grating before being finally acquired by the CCD. The interference images captured by CCD are subsequently analyzed using a self-developed “wave-front phase unwrapping unit” and “imaging performance analysis unit”. The information from the interference image extracted by the wave-front phase unwrapping unit can be used to detect and correct alignment errors of each lens in the optical system in three-dimensional space utilizing the corresponding relationship between the calculated wave-front information and the position deviation of the lens in the optical system. Meanwhile, the imaging performance analysis unit can put the measured wave-front information through image analysis to obtain imaging performance information such as Zernike phase-contrast, PSF and MTF.
In order to verify the feasibility and performance of the proposed system, numerical analysis and several experiments were conducted. First, in order to confirm that the design parameters of the binary checkerboard grating designed in this study are correct, the optical power meter is used to verify the light intensity efficiency of each diffraction order of the binary checkerboard grating. At the same time, the influence of non-order (±1, ±1) diffraction light produced by binary checkerboard grating and Talbot effect on the measurement results of wave-front image were verified through numerical analysis and experiments. In addition, to verify the accuracy of wave-front measurements, the measurement results were compared with commercial standard lenses. The results show that the average error between the measurement results of the shear interferometer-type wave-front sensor and the wave-front theory of ideal spherical lens is about 2.59%. Furthermore, in order to verify the optical system correction capability of the wave-front sensor, a position detection experiment is conducted on a confocal system consisting of two standard lenses. In the experiment, the relative three-dimensional position of the lens is changed while the corresponding wave-front information is confirmed. The experimental results confirm that the measured wave-front information can be used to reliably obtain alignment errors in the lens assembly. Finally, by inputting the wave-front information measured by the proposed wave-front sensor into the“imaging performance analysis unit” , imaging performance information such as Zernike phase-contrast, PSF and MTF of the tested optical system can be obtained. The experiments prove that the proposed system is capable of accurate wave-front measurement and image quality analysis, and can detect and correct the lens assembly position for optical imaging systems while providing the analysis data of optical image quality. The proposed wave-front sensor has the potential to see widespread use in the assembly processes of various optical systems as well as situations requiring imaging performance measurement or verification in the future.

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