Advanced sensors for multi-color infrared imaging bolometers

A new form of infrared (IR) imaging bolometer suitable for radiometric imaging of high temperature plasmas is presented, offering several key advantages: instantaneous power readout via an IR camera (within thermal timescale constraints), increased robustness and uniformity as compared to a traditional imaging foil, ease of calibration, and pixelated imaging. These advantages are accomplished with the use of silicon microfabrication techniques and vertically aligned carbon nanotubes. An additional feature of this approach is the ability to make a multi-color pixel array, which we call the red–green–blue imaging bolometer sensor. By customizing a pattern of individual neighboring pixels with different radiation absorption characteristics, imaging bolometers for multiple energy bands are possible. Since the thin film architecture for each pixel determines its respective photon stopping power, individual pixels can be designed to absorb varying levels of photon energy depending upon the presence of an optical absorber and a thin film stack of varying thickness and atomic number (Z). As a result, we can image three (or more) different energy bands of plasma radiation simultaneously, with hundreds, if not thousands, of lines of sight.