| 摘要 |
<p>A system, device and method to determine the location of a distal end of an insertion tool as it penetrates through biological tissue and into a desired site, such as the sclera and/or the choroid of an eye, are described. The system includes a light guide, a light source, a light sensor, and a logic unit. When the distal tip of an insertion tool traverses the relatively dense sclera of an eye, the reflecting plane of the sclera is positioned at or near zero distance relative to the distal tip of the light guide. Once the distal tip enters a less-dense choroid of the eye, the distance to the reflecting plane becomes greater than zero.</p> |
