The unique property of silica aerogel, to be transparent with a low thermal conductivity and the safety of the CO2 producing mode, provides the motivation for European Laboratories to work together in the field of transparent insulation materials under the framework of European projects (Joule II, Human Capital and Mobility). A couple of problems have to be solved to achieve the goal of manufacturing a double glazing filled with monolithic carbogel. To improve the mechanical and optical properties of carbogel for its application in double glazing, one has to know the relationship between the structure and the physical properties of the carbogel. Therefore, one has to analyze the structure of carbogel in a detailed manner. This paper discusses the change in particle size as a function of the polyethoxydisoloxane precursor to water ration. We present Tapping Mode and Contact Mode atomic Force Microscope Images of carbogel which supply 3D information about the carbogel surface. The measured images provide information about the particle's size in three dimensions in nanometer scale range.