A high-resolution SXGA+8.5μm pitch uncooled IRFPA with improved performances

Several IR sensor players, including LYNRED, have been communicating on pitch reduction of microbolometer based uncooled Thermal image sensors. Small microbolometer sensors will open the way to SWaP (Size Weight and Power) devices, and they are also a key enabling technology for high resolution detectors.

This paper will exhibit the features of a SXGA+ uncooled IRFPA with 8.5 microns pixel pitch designed by LYNRED, the largest format in the 8.5μm product family. This new product offers high resolution, while keeping NETD <60 mK (at sensor, without denoising algorithm), at frame rate up to 60 Hz. In previous communications, we have reviewed the pixel design compromises for the 8.5 microns pitch. This paper analyses the different challenges resulting from such a large FPA size combined with high pixel performances, such as output signal spread management, NETD, resolution gain, detection range and image quality.

At the same time, we have continuously improved the thermistor material. This product family, associated with this new 8.5 pitch technology, integrates a new Vanadium Oxide (VOx) thermistor with drastic thermal stability improvements. We will focus mainly on the reduction of the sun effect which is a key concern for the end-user.

The electro-optical characterizations of this large resolution Uncooled detectors will be presented. Fine Image quality and robustness to sun exposure achieved in various conditions, thanks to recent material improvements, will be shown and discussed.