Development of the new MWIR and LWIR hyperspectral imagers at Specim

Both MWIR and LWIR wavelength ranges have for long time mostly used for research activities. During recent years industrial use of these wavelength band ranges has also evolved and the same trend is expected to continue in future. Important application areas relate to mineral mapping and recognition, metal industry and black plastics sorting for instance. Key parameters in industrial use, in addition to good performance characteristics and data quality, are the cost and usability of the camera. The Specim hyperspectral MWIR and LWIR cameras employ push-broom imaging spectrograph, with transmission grating and on-axis optics. The cameras have thermally stabilized optics and cryogenically cooled MCT detector with Stirling cooler. The performance of the newly developed MWIR camera is targeted on reflectance measurements with illumination. The performance of hyperspectral camera enables reliable measurement of low reflectance level targets illuminated with moderate temperature heat source, and with less than 10% reflectance with 650°C illumination and frame rates of 380 frames /sec with 154 bands and 640 spatial samples. The SNR of 500 of the new LWIR hyperspectral camera suits emission measurements of normal room temperature targets but is applicable to reflectance measurement with illumination as well. High performance emission measurement with about 150 bands, 640 spatial samples and more than 300 frames per second can be achieved. The performance is verified with testing of several camera units and supported with simulation results. The performance characteristics of NESR and expected SNR with actual measurement parameters are presented.