利用差動共焦顯微術達到超越繞射極限的橫向解析率

Improving the Lateral Resolution beyond the Diffraction Limit by Using Differential Confocal Microscopy

李超煌(Chau-Hwang Lee) ； 江惠瑜(Hui-Yu Chiang) ； 蒙宏堯(Hong-Yao Mong)

《光學工程》 83期 (2003/09) Pp. 21-29

https://doi.org/10.30011/OE.200309.0003

摘要

差動共焦顯微術具有奈米級縱向靈敏度，因而能夠在不使用螢光染料標定的條件下，偵測到橫向尺寸小於光波繞射極限的表面三維奈米特徵。雖然在其表面地貌影像中，橫向解析率仍然受到光波繞射極限的限制，但只要影像有足夠的訊噪比，橫向解析率可藉最大近似估計影像還原演算法加以提高。從高空間頻率成分的訊噪比來估計，經過演算法處理的還原影像，其最佳橫向解析率可改善至波長的15%。對由複合材料構成的樣品而言，此技術還可以同時顯示小於光波繞射極限的地貌特徵與反射率的空間分佈。

關鍵字

差動共焦顯微術 ； 繞射極限 ； 最大近似估計 ； 影像還原

並列摘要

Because of its nanometer depth sensitivity, differential confocal microscopy is able to detect three-dimensional surface features of lateral dimensions smaller than the diffraction limit without fluorescence labeling. Although the lateral resolution of the topographic images is limited by diffraction, it can be enhanced by a maximum likelihood estimation algorithm as long as the signal-to-noise ration is high enough. According to the comparison of signal and noise at high spatial frequency, the best lateral resolution of the enhanced images can be as high as 0.151. On composite samples this technique can simultaneously display sub-diffraction-limit topographic features as well as the reflectivity heterogeneity.

並列關鍵字

differential confocal microscopy ； diffraction limit ； maximum likelihood estimation ； image restoration