銣原子 5S 1/2→ 5D 5/2在光鐘或是光譜學上有著舉足輕重的地位。藉由交叉譜線取得銣原子的掃描譜線結果為本實驗的主要分析對象。
本實驗使用 Optromix 公司生產的 Optromix-SFE-778-0200-FS CW Laser。並使用 PDH(Pound-Drever-Hall) 系統減少雷射的抖動。之後用紅色火龍果開發版(後面簡稱 red pitaya) 進行解調與回授讓雷射可以透過電光調制器將雷射鎖在銣原子的交叉譜線上，透過改變調制頻率進而改變雷射頻率來完成掃描譜線。最後和使用原本儀器的掃描譜線數據進行比較。
為了能夠盡可能的減少線寬，例: 碰撞增寬、賽曼增寬 (Zeeman broadening)，來提高進行 red pitaya 與原本儀器的掃描譜線數據比較時的靈敏度，因而架設了一個真空氣室與消除環境磁場的亥母霍茲線圈。用真空幫浦抽氣到至少 10^−7，並用全金屬閥門將銣原子安瓿封存，使其中的銣原子能依照需要分批使用。
最終雖然能夠進行鎖頻與掃描譜線，但是線寬和中心頻率有增寬和偏移。未來目標能在足夠修正 red pitaya 程式或是外加電路的情形下得到和原本儀器下一樣的線寬與中心頻率並進行更進一步的自動化應用。

This experiment utilized the Optromix-SFE-778-0200-FS CW Laser produced by Optromix. A Pound-Drever-Hall (PDH) system was employed to reduce laser jitter. Subsequently, red pitaya was used for demodulation and feedback, allowing the laser to be locked onto the crossover line of rubidium atoms through an electro-optic modulator. The frequency of the laser was then tuned by changing the modulation frequency to achieve frequency sweeping. Finally, the results were compared with the frequency sweep data obtained from the original instrument.
To minimize errors during comparison, a vacuum chamber and a Helmholtz coil to eliminate environmental magnetic fields were set up. The vacuum pump evacuated the chamber to at least 10^−7 torr, and rubidium atom ampoule were
sealed with all-metal valve, allowing the rubidium atoms to be used in batches as needed.
In the end, although frequency locking and spectral line scanning can be performed, the line width and center frequency are broadened and shifted. The future
goal is to obtain the same linewidth and center frequency as the original instrument by sufficiently modifying the red pitaya program or adding external circuits, and enable further automated applications.

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