| 摘要 |
An optical probe includes a rod-shaped microlens provided with a refractive index distribution in a radial direction, and an evanescent light generating portion formed on a first end face of said microlens. The refractive index distribution and the length of said microlens are such that parallel light that enters said microlens through the second end face converges while being transmitted through said microlens, and substantially focuses on the first end face. The evanescent light generating portion comprises a light-blocking film, which is provided with a micro-aperture formed substantially on an optical axis of the microlens. An aperture diameter of the micro-aperture is dimensioned such that the light transmitted through the microlens is leaked from the microlens as evanescent light only. Outside the micro-aperture, the light transmitted through the microlens is reflected or absorbed by the light-blocking film. It is also possible to use a planar microlens instead of the rod-shaped microlens. With this optical probe, it is possible to make the incident light energy large, the transmission losses small, the generation efficiency of evanescent light can be made high. The optical probe can be manufactured easily, and control of its positioning are easy.
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