Abstract

We have made a quantitative sensitivity analysis of a fiber-optic refractometer based on a geometrical model. The analysis shows that, by bending the sensor probe in a figure eight and varying its curvature, the sensitivity range can be adjusted arbitrarily and that high sensitivity in the lower refractive-index ranges is possible. The curvature giving optimum sensitivity at refractive index n is determined as a function of n/n₀, where n₀ is the probe refractive index. These results have been experimentally confirmed, and resolution of the order of 10⁻⁵ near the refractive index of water has been achieved.

© 1987 Optical Society of America