The intensities of the Cd 2288‐ and 2981‐A˚ and Cd+2144‐ and 2265‐A˚ lines have been measured as a function of Cd vapor pressure in the Cd‐Ar discharge. Except for the 2981‐A˚ line, the intensities are highest at Cd vapor pressures in the range 5–30 mTorr. The 2981‐A˚ line increases in intensity with increasing Cd vapor pressure in the 5–200‐mTorr range. Absolute radiant flux densities have been determined by calibrating the spectrometer response using a low‐pressure mercury discharge.