Miniature fiber-optic pressure sensor with a polymer diaphragm

Area of Science:

• Optical Engineering
• Biomedical Devices
• Microsystems Fabrication

Background:

• Accurate pressure monitoring is crucial in biomedical and industrial fields.
• Existing pressure sensors can be bulky, expensive, or lack biocompatibility.
• Miniaturization of sensing elements is a key trend in modern instrumentation.

Purpose of the Study:

• To fabricate and experimentally investigate a novel miniature optical fiber pressure sensor.
• To demonstrate a cost-effective and biocompatible design for disposable applications.
• To achieve high-resolution pressure sensing capabilities.

Main Methods:

• Fabrication of a micro-cavity at the optical fiber tip using wet etching.
• Integration of a thin polymer diaphragm within the fiber cavity.
• Formation of a Fabry-Perot interferometer between the fiber cavity and the diaphragm.
• Experimental characterization of sensor performance under varying pressures.

Main Results:

• Successful fabrication of miniature optical fiber pressure sensors (125 microm diameter).
• Demonstrated pressure sensing ranges of 0-40 kPa and 0-1200 kPa.
• Achieved a pressure resolution of less than 10 Pa.
• Validated the use of biocompatible materials for potential medical applications.

Conclusions:

• The developed micromachining technique enables the production of simple, low-cost, disposable optical fiber pressure sensors.
• The sensor design is suitable for both biomedical and industrial applications requiring precise pressure monitoring.
• The high resolution and biocompatibility highlight the potential of this technology for advanced sensing solutions.