Duo-membrane box was used as sensing component for atmospheric pressure. A micrometric displacement sensor with optical fiber was employed to inspect deformation of membrane box with air pressure changing

in order to avoid the defects in inspecting deformation

or improve and optimize performances of the sensors. A two-path optical fiber sensor was utilized to increase sensitivity and measure little changing in air pressure. The relation between optical fiber sensor output changes and atmospheric pressure changes was standardized with a standard air pressure gauge. A setup for measuring atmospheric pressure was formed. The experimental results indicate that measurement range is 900-1200hpa

resolution is 0.2hpa

and accuracy is ±0.1hPa. The measurement area position on air pressure may be changed via the changing of beginning of distance between optical detector and reflection face. Optimization of optical fiber detector parameters is necessaries to spread measurement range on atmospheric pressure.