本文關(guān)鍵詞： 激光自混合干涉 光學(xué)測量 氦氖激光器 FPGA 數(shù)據(jù)處理　出處：《南京信息工程大學(xué)》2016年碩士論文　論文類型：學(xué)位論文

【摘要】：激光自混合干涉是指激光器中的激光發(fā)射到外界物體上,被外界物體反射或折射以后,有一部分激光反饋到激光器中,與腔內(nèi)激光產(chǎn)生混合,導(dǎo)致激光器輸出功率、頻率發(fā)生改變,所以稱為自混合干涉。作為一門新興的光信號測量技術(shù),具有非接觸性、高準(zhǔn)確性、高精密度等特點(diǎn),已經(jīng)越來越普遍的應(yīng)用于外部物體機(jī)械量、幾何量及激光器參數(shù)等的測量。其中對于外部物體位移的測量和相位的提取是兩個主要的應(yīng)用。外部物體位移的傳統(tǒng)測量方法通常是先將實(shí)驗(yàn)數(shù)據(jù)采集并保存下來,再通過MatLab等數(shù)學(xué)軟件結(jié)合算法進(jìn)行處理最后得到物體的位移量和方向。這種方法的優(yōu)點(diǎn)是算法靈活、處理精度高；缺點(diǎn)是不能對干涉信號進(jìn)行高速實(shí)時處理與顯示。外部物體相位提取的傳統(tǒng)方法通常是利用MatLab等數(shù)學(xué)軟件結(jié)合算法進(jìn)行線下處理,沒有達(dá)到高速實(shí)時提取相位信息的目的。FPGA,即現(xiàn)場可編程門陣列,芯片具有開發(fā)周期短、工作頻率高、內(nèi)部程序并行運(yùn)行等特點(diǎn),是一種可集成如數(shù)據(jù)采集、處理和傳輸?shù)裙δ艿囊环N芯片。目前FPGA芯片在高速數(shù)據(jù)采集、高性能數(shù)字信號處理等領(lǐng)域應(yīng)用比較廣泛,因此可以采用FPGA設(shè)計(jì)一種高速有效的數(shù)據(jù)處理系統(tǒng)。本文以激光自混合干涉信號為研究對象,利用FPGA高速采集處理數(shù)字信號等優(yōu)勢,設(shè)計(jì)了基于FPGA的激光自混合數(shù)據(jù)處理系統(tǒng),本文主要完成的工作如下：1、提出了計(jì)算自混合干涉信號微位移的歸置比較法。完成了對振動條紋整數(shù)個數(shù)、小數(shù)值及方向的判斷,進(jìn)而求出微位移。將該算法結(jié)合QuartusⅡ進(jìn)行Verilog HDL實(shí)現(xiàn)。設(shè)計(jì)了基于FPGA的自混合干涉信號微位移測量系統(tǒng),進(jìn)行實(shí)驗(yàn)驗(yàn)證及分析,實(shí)驗(yàn)結(jié)果表明,該微位移測量系統(tǒng)具有高速實(shí)時性,數(shù)據(jù)反饋時間為0.5s,位移測量結(jié)果相對誤差較低,分別率可達(dá)兄／20,該微位移測量系統(tǒng)滿足對激光自混合干涉信號高速準(zhǔn)確的測量要求。2、分析了FFT相位提取理論并進(jìn)行了MatLab仿真分析。結(jié)合QuartusⅡ進(jìn)行FFT的Verilog HDL實(shí)現(xiàn)。設(shè)計(jì)了基于FPGA的干涉信號相位提取系統(tǒng),并通過實(shí)驗(yàn)驗(yàn)證。實(shí)驗(yàn)結(jié)果表明,該相位提取系統(tǒng)具有高速實(shí)時性,數(shù)據(jù)反饋時間為0.5s,基于FFT得到的相位值相對于實(shí)際相位值相對誤差較低,該相位提取系統(tǒng)滿足對干涉信號高速準(zhǔn)確的測量要求。
[Abstract]:Laser self-mixing interference refers to the laser in the laser emitted on the external object, reflected or refracted by the external object, a part of the laser feedback to the laser, and the intracavity laser mixing. As a new optical signal measurement technology, it has the characteristics of non-contact, high accuracy, high precision and so on. It has been more and more widely used in the mechanical volume of external objects. The measurement of geometric parameters and laser parameters. The measurement of displacement of external objects and the extraction of phase are two main applications. The traditional method of measuring displacement of external objects is usually to collect and save the experimental data first. Come on. Finally, the displacement and direction of the object are obtained by using MatLab and other mathematical software. The advantage of this method is that the algorithm is flexible and the processing accuracy is high. The disadvantage is that the interference signal can not be processed and displayed in high speed and real-time. The traditional method of phase extraction of external object is usually using MatLab and other mathematical software combined with algorithm for offline processing. The purpose of extracting phase information at high speed and real time. FPGA-Field Programmable Gate Array (FPGA). The chip has the characteristics of short development period, high working frequency, and internal program running in parallel. FPGA chips are widely used in high speed data acquisition, high performance digital signal processing and other fields. Therefore, FPGA can be used to design a high-speed and effective data processing system. In this paper, the laser self-mixing interference signal is taken as the research object, and the advantages of FPGA high-speed acquisition and processing of digital signal are used. A laser self-mixing data processing system based on FPGA is designed. The main work of this paper is as follows: 1. The homing comparison method for calculating the micro-displacement of self-mixing interference signal is proposed. The integer number, small value and direction of vibration fringes are judged. Then the micro-displacement is obtained. The algorithm is implemented with Verilog HDL combined with Quartus 鈪，

本文編號：1490933