結合共光程外差干涉術及表面電漿技術量測水中移動的氣泡數目

Using The Common-Path Heterodyne Interferometry and A SPR Angular Sensor to Measure The Number of Bubbles in Water

黃建銘(Jian-Ming Huang)

指導教授 ： 邱銘宏

國立虎尾科技大學/電機資訊學院/光電與材料科技研究所/碩士(2014年)

https://doi.org/10.6827/NFU.2014.00040

摘要

本文主要利用兩個聲光調制器(Acousto-Optic Modulator, AOM)來產生一外差光源，再配合表面電漿共振(Surface plasmon resonance, SPR)技術來檢測出水中的氣泡數目。
當光束在水中接觸到氣泡時，會因折射率的不同而造成光束偏離共振角，使得相位產生急遽的變化，而此相位變化經光偵測器(Photodetector)擷取再由鎖相放大器(Lock-In Amplifier, SR830)來解析相位，最後再把信號輸出至計數器上來完成氣泡數目的檢測。
最後，在實際量測氣泡時平均相對誤差為0.28%~2.29%。在模擬氣泡速度為2 時，可量測到的最小直徑為0.2 的氣泡；在模擬氣泡速度為60 時，可量測到的最小直徑為0.6 的氣泡。

關鍵字

外差干涉術 ； 共光程 ； 表面電漿 ； 氣泡檢測 ； 角度感測器

並列摘要

In this paper, we use two acousto-optic modulators (AOM) with a laser to produce a common-path heterodyne light source. This phase detection technique combines with a surface plasmon resonance (SPR) sensor is used to detect the number of bubbles in water.
When a bubble exposed to light in water, the light deviates from the resonant angle caused by the bubble to change the phase largely in the p-polarization. From the phase change, we should count the bubble 's number at a cross section in read-time.
Finally, in the actual measurements of bubbles, average relative error is 0.28% - 2.292%. When the speed of water is 2.0 , the measurable minimum diameter of bubble is 0.2 ; As the speed is 60 , the measurable minimum diameter of bubble is 0.6 .

並列關鍵字

heterodyne interferometry ； common-path ； surface plasmon resonance ； bubble detector ； angular sensor

參考文獻

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