A system and method to fully characterize the thermal behavior of complex 3D submicron electronic devices. The system replaces and/or supplements laser-based surface temperature scanning with a CCD camera-based approach. A CCD camera records multiple points of light energy reflected from an integrated circuit to obtain a temperature measurement. The system is used to non-invasively measure with submicron resolution the 2D surface temperature field of an activated device. The measured 2D temperature field is used as input for an ultra-fast inverse computational solver. The system couples measured results and computations in a novel approach, making it possible to extract geometric and thermal features of a device, and to obtain critically needed temperature distributions over the entire 3D volume of that device, including regions that are physically or optically inaccessible. The obtained distributions reflect the real, and not merely theoretical, physical construction and thermal behavior of that device.