本論文研究架構了一套相位與頻率偵測器(phase and frequency detector)系統，其中包含類比相位偵測器(analog phase detector)與數位式相位頻率偵測器(digital phase and frequency detector)。數位和類比偵測器是互不相容的，換言之，不論在任何情況下，只有其中一個偵測器是在工作的。如此設計的好處是可以同時擁有數位電路本身具有較大的捕獲範圍(capture range)的特性與類比電路高速、低雜訊的特性。此偵測器主要應用為光學鎖相迴路(optical phase locking loop，OPLL)，在實驗中，我們利用此系統在頻率30 MHz時成功地將兩個電壓控制振盪器或兩部Nd:YAG雷射鎖住，相位誤差(phase error)控制在13 mad左右。此外，此數位電路系統是由可程式邏輯元件所架構的，所以我們可以根據雷射所需要的相位及頻率穩定度，自行修改可程式邏輯元件的程式。

In this thesis we construct phase and frequency detector employing both an analog phase detector and a digital phase and frequency detector. The analog and digital detectors are mutually exclusive so that only one of them is active at any given time, resulting in a phase detector with both the broad capture range of digital circuits and the high speed and low noise of analog mixers. The detector has been used for phase locking two voltage controlled oscillator (VCO) or two Nd:YAG lasers at 30 MHz frequency difference. The rms phase error can be reached about 13 mrad. The digital circuitry is implemented with a programmable logic device, therefore, the detector can be easily adapted to other experiments requiring frequency/phase stabilization of lasers sources.

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