High-speed fiber-optic bolometry enabled by deconvolution signal processing

High temporal resolution measurements of radiated power are essential for fusion plasma diagnostics, where key phenomena evolve on millisecond and sub-millisecond time scales. Fiber-optic bolometers (FOBs) offer attractive advantages for plasma radiation measurement, including immunity to electromagnetic interference, high temperature capability, and compact size; however, their thermal dynamics are dominated by heat diffusion along the silica fiber stub, making lumped-mass models unsuitable for direct power reconstruction. In this work, we present a detailed deconvolution-based numerical signal processing approach that treats the FOB as a linear time-invariant system, enabling recovery of incident radiation power from measured sensor temperature via inversion of the system impulse response. Compared with prior demonstrations limited by millisecond-scale impulse excitation and low-bandwidth wavelength-based interrogation, we achieve more than two orders-of-magnitude improvement in temporal resolution and demonstrate successful reconstruction of radiation pulses as narrow as 250 μs, establishing FOBs combined with deconvolution processing as a promising tool for resolving rapid radiation transients in fusion plasmas.