Night vision goggles. The photodiode + CsO + lead coated charged glass capillary amp thing is apparently still superior to solid state image sensors with amplif

Night vision goggles. The photodiode + CsO + lead coated charged glass capillary amp thing is apparently still superior to solid state image sensors with amplifiers in metrics like SNR, minimum luminosity, and longer wave IR response. The performance gap is wide enough that there's a Chinese Norinco subsidiary that entered the market during 2010s by licensing technology from an EU company.