Optical wave guide for fiber-optic sensor, has axially extending section with regions trained in way such that light within regions escapes from cable and arranged to withdraw light back to axial ends of axial section

摘要

The wave guide (6) has an axially extending section (10) with regions (12) on a side (11) of the wave guide. The regions are formed and arranged in such a manner the light within the regions escapes from the wave guide and escapes back to one of the axial ends of the axially extending section or escapes back to a central region of the axially extending section. The regions are arranged such that axial distance of the regions decreases on one of the axial ends.