
The Saiki Laboratory is doing research on near-field optics. Its common knowledge that lenses can be used to focus sunlight into a small point. In the case of laser light, the point is even smaller, but the limit on the points size is about one micron. It cant be made any smaller. This is due to the diffraction limit of light, which is a basic obstacle that cant be overcome as long as lenses are used. The resolution of optical microscopes, the capacity of optical disks, and the process size in optical lithography are all restricted by the diffraction limit of light. The field of research that handles technology to overcome this barrier is called near-field optics. Q. Im currently considering the development of microscopes with extremely high spatial resolution, and how to apply them. The microscopes people normally use have a physical restriction called the diffraction limit. They cant be used to observe things smaller than one micron. But we want to construct microscopes that overcome this limit, to observe a new physical world. When light shines on a nanoscale object, some of it is scattered, while some remains around the object. The light remaining around the object is called evanescent light. It doesnt reach our eyes, as it stays on the object like a skin. So we cant usually know of its existence. The extent of the evanescent light is about the same size as the object, so it isnt subject to the diffraction limit; instead, it functions as an extremely small spot of <b>...</b>
Keio
university
Toshiharu
Saiki's
Group
Near-field
optics
Diffraction
limit
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