This image was acquired from
wikimedia. It was marked as Public Domain or CC0 and is free to use. To verify, go to the source and check the information there.
Keywords from Image Description:
Ion spectral line radiation from krypton arc lamp. en This photo shows the spectral line radiation from krypton arc lamp While the light looked almost white to the human eye the camera images the very strong infrared line at nanometers as purple own January UTC Zaereth talk Zaereth en Original upload log en ftcg page en Ionspectrallineradiationfromakryptonarclamp