A new type absolute radiometer

named Dual Cavity Inter-Compensating Absolute Radiometer(DCICAR)was constructed. A conical cavity of DCICAR is fabricated as a whole body by combined the conical part with the cap brim for heat conduct and a Pt resistance is used as temperature sensor. The DCICAR works in a mode of inter-compensated when the two cavities are put side by side and faced the same field of view(FOV)

also kept the same states of heat conducting

convection

dissipation and heat sink in the same temperature environment. The two cavities are always heated in the same temperature through the whole measurement process. Experimental results show that the repetition of DCICAR is better than 0.05%. By taking the SIAR-2c (Solar Irradiance Absolute Radiometer) as transfer standard demonstrated in the Tenth International Pyrheliometer Comparisons (IPC-X) organized by World Radiation Center (WRC) at Switzerland in 2005

the correct factor of channel A of DCICAR relatively to World Radiation Reference(WRR) is 0.999 73

and the channel B of 0.999 17. So DCICAR can be well coincident with WRR in 0.1%.It concludes that the compensation effect of DCICAR is improved with a short time constant and high sensitivity. The measurement results from two cavities could be compared and validated with each other.