A spectroscopic diagnostic method, to measure electron temperature of radiationheated CH foam on Shenguang Ⅱ laser facility, is described. A tracer layer of aluminum was embedded in the middle of the CH foam and a point-projection method used in the opacity experiment was induced to measure the transmission spectrum of the embedded Al foil. The electron temperature, of about 80 eV, was deduced through a comparison of the experimental absorption spectrum with the calculated one with a detailed level accounting opacity code. The results of hydrodynamic simulation show that it＇s reasonable to determine the CH foam temperature by measuring the embedded Al absorption spectrum. Thus, the electron temperature of radiationheated CH foam was obtained.
