本文架設一套差動式共焦顯微系統，並設計一模糊滑動控制器來抑制共焦顯微系統中掃描平臺的軸向擾動量。系統以麥克森干涉儀為感測器的位置回授裝置，實驗驗證，控制器可有效抑制12dB軸向擾動量，使掃描平臺動態定位穩態誤差小於25nm以下。 共焦顯微系統系統的縱向位移反應曲線斜率為2.03/?m，在考慮0.3%光源雜訊下，具有4nm的軸向解析度。本文選用鋁鍍膜試片作為樣本，經由自行架設的共焦顯微系統，經光強度-階高換算測得試片表面階高為369.4nm。 In thesis , A differential co confocal microscopy, which with a fuzzy controller for suppressing the longitudinal disturbance of scanner in confocal microscopy, was developed. The system use Michelson interferometer as position control sensor. The experimental result shows that the fuzzy controller is effective in 12dB of the longitudinal disturbance suppression. And the system's position error is within 25nm. The experimental result shows that the slop of the intensity versus longitudinal displacement (SILD) curve is enhanced to 2.03/?m. To consider 0.3% noise in the system, a depth resolution as high as 4 nm has been achieved. A al-coating step height was measured. According to the difference of intensity and the SILD, a 369.4 nm step height was obtained.