The invention provides a spectrum
irradiance standard
light source which is used for radiometric calibrations of
ultraviolet optical instruments, which comprises a
light source component, a lifting holdfast, a collimating component and a lamp chamber, wherein a window which is used for output
xenon lamp radiations is opened on the front end of the lamp chamber, an
xenon lamp power supply is connected with an
xenon lamp electrically, a port of a cylinder
lens hood is communicated with the window which is on the lamp chamber and installed concentrically, a piece of lens and a diaphragm are arranged in turn on an
xenon lamp radiation light path inside the
lens hood, the
xenon lamp is located on the focus of the lens, the diaphragm is located on the other side of the lens, the collimating component and the lamp chamber are installed commonly on the lifting holdfast. An extra-quiet
xenon lamp which is selected by the invention has a short arc xenon lamp which has a comparatively strong
radiation strength in an
ultraviolet wave band, the invention also adopts a highly durable
cathode which enables arc points of the xenon lamp with no drifts and fluctuations, the
light source can be usedfor
ultraviolet wave band 200-2000nm, visible
wave band and near
infrared wave band, and in particular for the ultraviolet wave band with a wave length less than 400nm, and the
signal-to-
noise ratio of calibrations can be increased effectively due to high irradiances.