【摘要】：光纖光鑷具有體積小、易于使用、成本低等特點(diǎn),可用于捕獲和操作微納粒子,這種捕獲和操作技術(shù)可以廣泛的應(yīng)用與生物學(xué)和醫(yī)學(xué)。對于一般的光纖光鑷,捕獲細(xì)胞時都會一定程度的接觸細(xì)胞,這會對生物樣品造成一定的損傷。因此,具有長操作距離的光纖光鑷對于實(shí)現(xiàn)非接觸式的光學(xué)捕獲具有重要的意義。長距離的光鑷操作距離可以很大程度的提高光鑷應(yīng)用性和不接觸的捕獲細(xì)胞的靈活性,本文對長距離操作細(xì)胞的光纖光鑷即長程光鑷進(jìn)行了研究。本文提出了一種新型的光纖錐角在58°操作距離在40μm之上的漸變折射率光纖長程光鑷。根據(jù)光纖光鑷的原理和光在漸變多模光纖中的傳輸特性來設(shè)計此種光鑷。在現(xiàn)有的漸變折射率光纖光鑷的基礎(chǔ)上,在單模光纖和多模光纖中加入了一段空氣腔來實(shí)現(xiàn)光鑷的長操作距離。調(diào)節(jié)空氣腔的長度,可以使得光在漸變折射率光纖錐頭的匯聚距離發(fā)生改變,也能使得任意長度的漸變多模光纖都能穩(wěn)定的捕獲細(xì)胞,提高了腐蝕出來的漸變多模光纖的使用率。通過數(shù)值仿真計算了空氣腔中、漸變多模光纖中和光纖錐附件的光場分布。仿真研究了漸變折射率光纖長度和空氣腔的長度對光在錐尖外聚焦距離的影響。仿真結(jié)果顯示通過調(diào)節(jié)漸變多模光纖長度和空氣腔的長度,可優(yōu)化光纖光鑷捕獲細(xì)胞的效果。實(shí)驗(yàn)中通過化學(xué)腐蝕法得到錐角較大的漸變折射率光纖錐,用毛細(xì)玻璃來制作空氣腔結(jié)構(gòu)。作為驗(yàn)證,實(shí)驗(yàn)中當(dāng)調(diào)節(jié)空氣腔的長度為100μm時,在穩(wěn)定的在有恒定流速12μm/s溶液中成功的捕獲了酵母細(xì)胞。實(shí)驗(yàn)捕獲細(xì)胞的距離超過了40μm,是之前漸變折射率光纖光鑷捕獲距離的10倍以上;并且在穩(wěn)定捕獲后,快速移動錐尖到細(xì)胞,細(xì)胞很快恢復(fù)到原有穩(wěn)定的位置,這證明了捕獲細(xì)胞的穩(wěn)定性;在有恒定流速的溶液中,穩(wěn)定捕獲的情況下,增加光功率能增大細(xì)胞的捕獲距離,這證明了可以通過該種光鑷長距離的操作細(xì)胞。通過上述實(shí)驗(yàn),成功的證明了這種設(shè)計的光鑷的可行性,實(shí)現(xiàn)了操作簡單、重復(fù)性好的長程光鑷。在實(shí)驗(yàn)之后,運(yùn)用米氏散射模型中光軸向力的計算公式來計算此種光鑷軸向力的分布,當(dāng)合力和細(xì)胞受到粘滯力的大小相等時,細(xì)胞計算出來的捕獲距離和實(shí)驗(yàn)的捕獲距離接近,進(jìn)一步證明了此種長程光鑷的合理性。這種光纖長程光鑷具有成本低,易于制作和易于使用的特點(diǎn),是一種較為理想的光纖長程光鑷。
[Abstract]:Fiber optic tweezers have the advantages of small size, easy to use and low cost. They can be used to capture and operate micro and nano particles, which can be widely used in biology and medicine. For general optical fiber tweezers, the cells are caught in contact with the cells to a certain extent, which will cause certain damage to biological samples. Therefore, fiber optic tweezers with long operating distance are of great significance for non-contact optical capture. Long distance optical tweezers can greatly improve the application of optical tweezers and the flexibility of non-contact trapping cells. In this paper, the optical fiber tweezers of long distance operating cells, that is, long range optical tweezers, are studied. In this paper, a new type of fiber tapered fiber long range tweezers with a tapered angle of 58 擄operating distance of 40 渭 m is proposed. The optical tweezers are designed according to the principle of optical tweezers and the transmission characteristics of optical fiber in a graded multimode fiber. Based on the existing graded refractive index optical tweezers, a section of air cavity is added to the single-mode fiber and multi-mode fiber to realize the long operating distance of the optical tweezers. Adjusting the length of the air cavity can change the convergent distance of the light in the tapered tip of the graded refractive index fiber, and it can also make the graded multimode fiber of any length be able to steadily capture the cells. The utilization rate of the corroded multimode fiber is improved. The field distribution of graded multimode fiber and fiber cone attachment in air cavity is calculated numerically. The effects of the length of graded refractive index fiber and the length of air cavity on the focusing distance of the light outside the cone tip are simulated. The simulation results show that the effect of optical fiber tweezers can be optimized by adjusting the length of multimode fiber and the length of air cavity. In the experiment, a gradient refractive index fiber cone with large cone angle was obtained by chemical etching method, and capillary glass was used to fabricate the air cavity structure. As a validation, yeast cells were successfully captured in a stable solution with a constant flow rate of 12 渭 m / s when the length of the air chamber was adjusted to 100 渭 m. The distance of the trapping cells was more than 40 渭 m, which was more than 10 times the distance of the graded-index fiber optical tweezers, and after the steady capture, the cells quickly moved the tip of the cone to the cells, and the cells quickly returned to the original stable position. This proves the stability of the trapping cells, and in the case of steady trapping in the solution with constant flow rate, increasing the optical power can increase the trapping distance of the cells, which proves that the long distance operating cells can be obtained through this kind of optical tweezers. Through the above experiments, the feasibility of the designed optical tweezers is proved successfully, and the long range optical tweezers with simple operation and good repeatability are realized. After the experiment, the distribution of the axial force of the optical tweezers is calculated by using the formula of optical axial force in the Michlet scattering model. When the force and the cell are subjected to the same viscous force, the distribution of the axial force of the optical tweezers is calculated when the force is equal to that of the cell. The calculated trapping distance is close to the experimental trapping distance, which further proves the rationality of the long-range optical tweezers. This kind of fiber long-range optical tweezers has the characteristics of low cost, easy to manufacture and easy to use, so it is an ideal fiber long-range optical tweezers.
【學(xué)位授予單位】：電子科技大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：TN253

【參考文獻(xiàn)】

相關(guān)期刊論文 前1條

1 霍鑫;潘石;;近場納米光纖探針腐蝕制備技術(shù)概述[J];電子顯微學(xué)報;2006年05期

，

本文編號：2286291