一次微分進(jìn)行激光穩(wěn)頻的思路

摘 要：為提高碘穩(wěn)頻激光器穩(wěn)頻方法的可靠性，并研究一次微分在穩(wěn)頻激光中的應(yīng)用效果。采用仿真的形式對碘穩(wěn)頻激光器輸出信號進(jìn)行模擬，通過分析各類微分信號的控制特性，研究可以參與控制的微分信號。通過公式推導(dǎo)出一次微分信號存在偏移情況。通過仿真對一次微分信號與三次微分信號的穩(wěn)頻特性進(jìn)行對比評價(jià)。結(jié)果表明，一次微分信號遠(yuǎn)大于三次微分信號，但一次微分信號存在偏移，提出一種利用一次微分信號進(jìn)行穩(wěn)頻控制的方法，克服背景信號多普勒效應(yīng)引入的頻率偏移；仿真計(jì)算表明，相比三次微分穩(wěn)頻方法，該文方法的控制范圍更大、穩(wěn)頻精度更高。說明采用一次微分信號控制的穩(wěn)頻系統(tǒng)可以有效改善穩(wěn)頻特性。并可以嘗試使用單片機(jī)對穩(wěn)頻系統(tǒng)進(jìn)行數(shù)字化改進(jìn)。

關(guān)鍵詞：碘穩(wěn)頻激光；激光穩(wěn)頻；穩(wěn)頻技術(shù)；一次微分；He-Ne激光

中圖分類號：TN248 文獻(xiàn)標(biāo)志碼：A 文章編號：2095-2945（2024）27-0041-04

Abstract： In order to improve the reliability of the frequency stabilization method of iodine frequency stabilized laser， the application effect of primary differential in frequency stabilized laser is studied. The output signal of iodine frequency stabilized laser is simulated in the form of simulation. By analyzing the control characteristics of all kinds of differential signals， the differential signals which can participate in the control are studied. The deviation of the primary differential signal is deduced by the formula. The frequency stabilization characteristics of primary differential signal and cubic differential signal are compared and evaluated by simulation. The results show that the primary differential signal is much larger than the cubic differential signal， but the primary differential signal has offset. A frequency stabilization control method using the primary differential signal is proposed， which overcomes the frequency offset caused by the Doppler effect of the background signal. Simulation results show that， compared with the cubic differential frequency stabilization method， the control range of this method is larger and the frequency stabilization accuracy is higher. It shows that the frequency stabilization system controlled by primary differential signal can effectively improve the frequency stabilization characteristics and efforts can be made to use single-chip microcomputer to improve the frequency stabilization system digitally.

Keywords： iodine frequency stabilized laser; laser frequency stabilization; frequency stabilization technology; first differential; He-Ne laser

自1960年美國科學(xué)家首次成功研制出紅寶石激光器以來，高強(qiáng)度穩(wěn)定光源領(lǐng)域已經(jīng)實(shí)現(xiàn)顯著的技術(shù)進(jìn)步。當(dāng)前激光技術(shù)已涵蓋多種類型的激光器，包括固體激光[1]、半導(dǎo)體激光[2]和氣體激光等，每種類型均有其獨(dú)特的應(yīng)用領(lǐng)域和技術(shù)特性。

在長度測量的領(lǐng)域中，激光波長的應(yīng)用作為一個基準(zhǔn)標(biāo)準(zhǔn)[3]，已經(jīng)成為精確度的關(guān)鍵因素。激光頻率的穩(wěn)定性直接影響到長度測量的準(zhǔn)確性[4]。在這個背景下，碘穩(wěn)頻激光器被國際計(jì)量標(biāo)準(zhǔn)機(jī)構(gòu)推薦使用[5]，這種穩(wěn)定性是通過控制激光器的輸出頻率來實(shí)現(xiàn)的。……