F. Javier Gonzalez College of Optics and Photonics/Univ. of Central Florida (United States) James Lee Porter Raytheon Missile Systems Co. (United States) Glenn D. Boreman College of Optics and Photonics/Univ. of Central Florida (United States)
Uncooled bolometric detectors used in infrared imaging systems have slow time constants (~10 ms) which makes them impractical for fast-frame-rate applications. Antenna-coupled microbolometers are fast uncooled detectors with good sensitivity, directivity and can be polarization and wavelength selective. These detectors have collection areas in the order of 10 μm2 which are too small for infrared imaging systems where a typical pixel area ranges from 20 × 20 μm2 to 50 × 50 μm2. In this paper two different types of detectors that can cover a typical pixel area are fabricated and their performance measured. The first type of IR pixel is a two-dimensional array of serially connected antenna-coupled microbolometers. These arrays can cover any pixel area and increase the signal-to-noise ratio of a single detector by a factor of N for an N×N array. The second IR pixel was fabricated by using a Fresnel Zone Plate Lens (FZPL) to collect and focus energy to a single antenna-coupled detector. An FZPL-coupled detector of 200 µm in diameter showed a 2× increase in D* compared to single element detectors. An 8 × 8 array of antenna-coupled pixels were fabricated on a commercial ROIC, measurements made on this antenna-coupled infrared focal plane array showed that the integration of antenna-coupled detectors to a commercial ROIC is possible.