Microbolometer uncooled infrared camera with 20mK NETD

Raytheon Sensors and Communications Systems has developed a prototype infrared imaging rifle-sight using an uncooled, microbolometer FPA. The Longwavelength Staring Sensor (LWSS) has been characterized by NVESD, where it demonstrated NETD and MRT values that are unsurpassed for uncooled FPA technology. The NVESD-measured NETD values were 24mK with f/0.7 optics and 42 mK with an f/1/0 aperture. When used with the f/0.7 optics, NVESD measured MRT values less than 60 mK at the nyquist spatial frequency. Similar measurements at f/1.0 produced MRT values less than 110 mK. Further optimization of the microbolometers is expected to produce FPAs with NETD values less than 20 mK for f/1.0 apertures The high-performance uncooled microbolometer FPA (SBRC-151) used in the LWSS was developed by Raytheon Santa Barbara Research Center. The 320 x 240 FPA utilizes a high-yield CMOS readout integrated circuit (ROIC) that achieves high sensitivity, low output nonuniformity, and large scene dynamic range. The ROIC provides multi-level, on-chip nonuniformity correction and on-chip temperature compensation. The FPA has 50 mu m x 50 mu m pixels and operates at frame rates up to 60 Hz with a single output. The VOx microbolometer detectors are produced at SBRC using an advanced dry-etch fabrication process. In addition to the LWSS project, SBRC has initiated low-rate production of the microbolometer FPAs. This work is being performed in support of Raytheon-Amber for commercial radiometer cameras. The pixel operability of the production radiometer FPAs (AE-189) are greater than 99.9%.