Quantiser requirements for next-generation uncooled thermal imagers

Detector technologies are being developed which offer the potential for thermal imagers to become much more widespread, making use of ferroelectric FPAs to reduce cost and improve the ease with which thermal imagers can be used, both in civil and military applications. The critical electronic components, apart from the detector array itself, are the quantiser components. The signal conditioning architecture described here minimises the power consumption and cost by using only high resolution DAC components, and digitising directly only the resolution required by the display (≈8-bit) rather than that imposed by the detector array (≈14-bit). The critical parameters for the quantisers are settling time, imposing a requirement for high analogue bandwidth in relation to sample rate, and power consumption. The architecture described here minimises the requirement for absolute accuracy in these devices