Comment by cthulhuology

Reading the article it hints at the reality that it doesn't actually work like passive glasses as it implies. the blueshift effect happens because they're using a laser to excite the crystal and it later emits the shifted light, but you have to pump a lot of energy in for that output. Simple conservation of energy implies this won't work for normal night vision applications, instead they want to shine a laser spotlight and use the reflected infrared laser light for vision. cool material science for sure, but not a replacement for nightvision goggles which don't broadcast your position with a bight spotlight.