Parallel Polydimethylsiloxane-Cavity Fabry-Perot Interferometric Temperature Sensor Based on Enhanced Vernier Effect

This study proposes an experimental implementation of temperature sensing system to study the enhanced Vernier effect using two polydimethylsiloxane (PDMS)-cavity Fabry-Perot interferometers (FPIs) arranged in parallel. However, these devices exhibited opposite responses to temperature; that is, with an increase (or decrease) in temperature, the two FPIs shifted in red and blue wavelength directions, respectively. This indicated that the sensitivity amplification of their parallel configuration was considerably larger than that generated by the traditional Vernier effect. Experimental results showed that the temperature sensitivities of the two FPIs were −0.42 and 1.36 nm/°C while that of their parallel structure was −14.6 nm/°C corresponding to an amplification factor of 10.7, which was much larger than that (8.2) of the traditional Vernier effect.