介電質微米穹形珠體的光子奈米噴流

Photonic nanojet of a dielectric micro-dome

李易庭(Yi-Ting Li)

指導教授 ： 林清彬

淡江大學/工學院/機械與機電工程學系碩士班/碩士(2019年)

https://doi.org/10.6846/TKU.2019.00061

摘要

光子奈米噴流的光點遠小於入射光波長且具有能量集中的特性，可以用來檢測和成像尺寸遠低於繞射極限的物質。本研究提出一種新穎的方法製造穹型珠體，首先將家幽靈蛛（Pholcus phalangioides）的曳絲浸潤於感光性UV膠(dragline silk)，藉由蜘蛛絲的集水特性，感光性UV膠會在蜘蛛絲表面自然形成紡錘珠體(spindle-knots)，再將未固化的紡錘珠體與低表面能的白蠟平板接觸後，藉由白蠟的斥水效應將紡錘珠體變為微米穹型珠體(micro-dome)，接著使用UV光給予固化成微米穹型珠體，最後經由三種雷射光波長(405nm、532nm、671nm)照射下產生光子奈米噴流。本研究使用時域有限差分法來模擬不同入射光波長對不同尺寸微米穹型珠體之光子奈米噴流的光場分佈和光強度的變化及使用共軛焦及自行架設出三軸雷射微調系統來觀察不同尺寸微米穹型珠體的光子奈米噴流現象，並撰寫電腦程式分析光子奈米噴流現象的各種參數，包括噴流焦距、半高全寬、衰減長度等。經由模擬與實驗結果的互相比較，本研究發現不同尺寸的微米穹型珠體均能增加光子奈米噴流的聚焦效果、增加焦距長度、及增加聚焦強度。

關鍵字

光子奈米噴流 ； 蜘蛛絲 ； 紡錘體 ； 穹型珠體 ； 繞射極限

並列摘要

Photon nanojet has two characteristics, namely that the spot is much smaller than the incident wavelength and concentrates energy, so photon nanojet can provide a tool for observing and imaging substance dimension below the diffraction limit. This study proposes a novel method for making micro-dome beads. First, the surface of Pholcus phalangioides is dipped into a photocurable UV resin. Due to the water-collecting properties of the spider silk, the surface of the spider silk naturally forms a spindle-shaped bead, and then the uncured spindle bead is touched with the white wax plate. The liquid spindle bead is transformed into a micron-sized dome by the water repellent effect of the white wax, and then the liquid micro-dome is cured by UV light irradiation. Finally, photon nano jet is generated by irradiation of three kinds of laser light wavelengths (405 nm, 532 nm, 671 nm). In this study, the finite-difference time-domain method is used to simulate the light field distribution and light intensity of different laser light wavelengths for different sizes of micron-sized bead bodies. And using a conjugate focal length microscope and self-erecting a three-axis laser trimming system to observe the phenomenon of photon nanojet flow in different size micron-sized beads. And write a computer program to analyze the various parameters of the photon nanojet phenomenon, including the focal length, the full width at half maximum, and attenuation length. Through the comparison of simulation and experimental results, this study found that different sizes of micron-sized dome bead can increase the focusing effect of photon nanojet, increase the focal length, and increase the focusing intensity.

並列關鍵字

Photonic nanojet ； Spider silk ； Spindle-knots ； Dome beads ； Diffraction limit

參考文獻

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