Development of microscopic and manipulating system in the optical near filed by evanescent photon force

本论文主要研究了存在于光学界面边界的倏逝光子力，以实现对粒子和生物样品的观察和操纵，取得了以下研究成果.作为一种光纤机械手，设计了一种在光纤端部粘贴直径为10 μm的乳胶球的方法。为了确定最佳的光学系统，利用时域有限差分法（FDTD）的电磁场分析计算了操纵器出射光束的方向图，并设计了实现对粒子操纵和捕获的结构.当YAG激光（波长为1.06 μm）入射到所制作的光学操纵器上时，可以实现对水中粒子的捕获和操纵。特别是，我们清楚地表明，一个直径为40 nm的金粒子是能够被捕获和操纵的，我们成功地安排了两个或更多的粒子.将直径为100 nm的金粒子固定在光纤操纵器所用球透镜的顶端，成功地观察到了倏逝光的散射.两束反向的激光以超过临界角的入射角入射到棱镜上，对棱镜表面的粒子施加反向的倏逝光子力。通过调节激光强度，我们成功地实现了直径约为10 μm的粒子以每秒几十微米的速度定位.作为一种非接触、非破坏性的微小物体定位新技术，提出了一种基于倏逝光子力的微小物体定位方法，并证明了直径为20 μm的乳胶球在二维平面内的位置可控性。

This research was focused on evanescent photon force, which exists at border of optical interface, in order to observe and manipulate a particle and a biological sample, and following results were obtained.1. As an optical fiber manipulator, the method of gluing a latex ball with a diameter of 10 μm on optical fiber end was devised. In order to clarify an optimum optical system, an exiting beam pattern from the manipulator was calculated using electromagnetic field analysis by FDTD method, and the structure was designed in order to realize a manipulation and trapping of particle.2. When the YAG laser light (wavelength of 1.06 μm) was incident on the fabricated optical manipulator, and a particle was possible to trap and manipulate in water. Especially, it was shown clearly that a gold particle with a diameter of 40nm was able to be trapped and manipulated, and we succeeded in arranging two or more particles.3. The gold particle with a diameter of 100nm was made to fix at the apex of ball lens used in the optical fiber manipulator, and the scattering of an evanescent light was observed successfully.4. Two opposite laser beams were incident on the prism by the incidence angle beyond a critical angle, and the evanescent photon forces for reverse direction were given to the particle on the surface of a prism. We succeeded in positioning a particle with a diameter of about 10 μm at the speed of a few tens of micrometers per second by adjusting laser intensity.5. As a new technology of positioning for the small object with non-contacting and non-destruction manner, the method by evanescent photon force was developed and it was shown that the position of latex sphere of 20 μm in diameter was controllable in a two-dimensional plane.