Fiber-Optic Bolometers for Fusion Plasma Diagnostics

Bolometers are widely used in fusion devices for measurement of plasma radiation. They are essential for energy balance estimate, exhaust control, disruption mitigation, and study of plasma instability. Existing bolometers are electronic devices whose performance degrades significantly in the harsh fusion environment characterized by the presence of strong electromagnetic interference, high temperature, vibration, and strong radiation. This project is aimed at the commercialization of novel fiber-optic bolometers (FOBs) that can meet the challenges. In Phase I, Nusenics has demonstrated the feasibility of FOB fabrication methods with reduced labor cost, improved reproducibility, mechanical stability, and temperature capability, constructed a fourchannel system, and tested the system in the lab environment that shows high detection sensitivity, fast response, and high temperature capability. Phase II will continue the development needed for transforming the technology into a viable product. Specifically, Nusenics will design FOBs with optimized performance, develop streamlined FOB fabrication and packaging process, develop fast signal processing method for real-time measurement, develop an in-situ calibration system, improve resistance to irradiation, carry out irradiation test, and develop prototype systems and work with potential end users for evaluation and testing. Thermal fusion has the enormous potential of providing immense energy with no emission of greenhouse gases and minimum waste. Commercialization of FOBs will provide the fusion community with a critically important tool for the development and operation of fusion devices.