Preparation And Study Of Optical Fiber Optical Tweezers

Optical tweezer has been invented for just over25years, which is widely used, as a new technology, has played a imazing role in physics, chemistry, biology, materials, and other fields. In the past ten years, optical trap technology combining with biochemical method made significant progress in the biological research. In the traditional atom trap and condensed matter research areas, optical tweezers is still irreplaceable todayOptical fiber has a hundred years of history, and with the birth of laser, the fiber technology has new and important applications. In the latter twenty years of20th century, optical fiber communication grows explosively. Large scale application of industry production of fiber technology, the cost-to use of fiber decreased exponentially. At the same time, in the research areas, low loss and wide bandwidth was no longer sufficient to meet the needs of scientist. The fiber transmitting several of special modes light began to appear. In the application of optical tweezers, optical fiber has lagged far behind the pace of times. Optical fiber trapping micro particles in the special direction has been reported for the first time in the international in1993. Since then, scientists began to aware that fiber optical tweezers would have a good development prospect. Some even asserted that the miniaturization of optical tweezers would dependent on the optical fiber. In the21st century, the reports on the application of optical fiber on the optical tweezers become more and more.In this paper, firstly, we reviewed the history and representative latest research of optical tweezers development, and then discussed the principle and the basic equipment of fiber optical tweezers. In the forth chapter, the fore exerted on the particles in the light fields formed in the output of different shapes optical fiber was discussed in detail. With the exiting research condition, we designed and manufactured special optical fiber end with melt drawing, cutting and chemical corrosion. The inclination angle of flat fiber end was below0.5mrad, and the largest taper angle of conical fiber end and complex cone was up to31°。The single optical fiber designed by ourselves can directly trap micro particles and biological cells.In the third chapter, orthogonal optical tweezers system was designed basing on the flexible character of fiber optical tweezers at the aid of conventional optical tweezers. We detected the trapping signals in the lateral direction. In the experiment, live human red blood cells were specially used for the samples, which provided a reference for the vivo research of optical tweezers. At the same time, optical tweezers was also made attempted to be used for the education. In order to make light mechanical effects to be easily understand and observed, the new designed optical tweezers can rotate and manipulate live human red blood cells. Modular design and mechanical design of new fiber optical tweezers spend us much time, but the system was satisfactory. In the new designed optical tweezers, the adjustment of orthogonal laser path was independent on the sample cell and microscope system, so we employed the plug-in architecture to make different functional modular couple easily.