The QHY 991 is a scientific cooled short wavelength infrared (SWIR) camera featuring the Sony IMX991 InGaAs sensor with a square 5µm x 5µm pixel array and 0.4 million effective pixels. This chip has a wide waveband (0.4um-1.7um) with high sensitivity. QE is up to 77% at 1200nm. By using Cu-Cu interconnect technology, the sensor has very low fixed pattern noise and a low pixel defect ratio.
Both QHY990 and QHY991 include a 25mm filter holder. The 25mm filter standard is common for lab applications. SWIR filters can easily be installed inside the camera with the included adapter, keeping the C-mount 17.5mm backfocus requirement.
Both the QHY990 and QHY991 can be specified with air cooling or liquid cooling to suit your requirements. The air cooling can reach -35C below ambient. With liquid cooling you can get to -45C below ambient with normal temperature liquid, or up to -60 to -80C below ambient with chilled liquid.
Typically the InGaAs sensor has a higher dark current than Silicon-based material. If you are doing long exposure imaging with this camera (eg. exposure >5 sec), QHYCCD recommends selecting the liquid cooling version.
Sony's SWIR image sensor technology is used to make the top InP layer, which absorbs visible light, thinner, making it possible to transmit light to the InGaAs layer underneath, delivering high quantum efficiency even in the visible range. This design enables imaging in a broad range of wavelengths from 0.4μm to 1.7μm, enabling the use of a single camera instead of the conventional multiple that were required to capture visible light and SWIR.
Applications: SWIR Astronomy Imaging and Photometry, Daytime Star Observing, Optical Communication, Optic Labs.