The remote control of a scientific instrument is a topic gaining more and more attention between the instrument users and operators. The project presented in this article starts from the mix of two separated research works and evolves first obtained results. The mixed works are the realization of an application to remote-control Scanning Electron Microscope (SEM), and the implementation of a procedure to reconstruct 3D surfaces.The remote control application is a server/client application [1], and [2]. The main aspect of this server/client application is that it has been designed and developed to work on public network. The remote commands implemented on the client application concern the connection to the server application, the connection to the microscope, the management of microscope controls, the communication with the local operator and the video streaming of specimens' images. Excluding last feature, the communication between client application and microscope is real-time in every case. Then, on the base of these favourable results, and considering the 3D reconstruction tool characteristic, this has been easily added to the remote application. In fact the 3D tool extracts the third dimension from back-scattered electrons [3]. This method for reconstructing the depth map in the SEM is founded on 4-Source Photometric Stereo (PS) technique which is based on the so-called reflectance map that uses several images of a surface, taken from the same viewpoint but under different lighting directions, to estimate the relative surface depth at each image point. The image acquisition process may require or specific instrumentation (4-sector, independent channel axial BS detector), or very standard SEM configuration and specimen rotation/translation. In this last case an alignment procedure had been developed [4]. To simulate different lighting conditions in a standard SEM it is necessary to rotate the specimen under the fixed detector and to acquire sequentially four images of the same specimen upon imposing three 90° rotation steps on the specimen, and then rotating back the images: a sequence of four pictures of the same area will be obtained, each of them illuminated from a different lighting direction. All these microscope operations are executed on remote control without any delay, then the 3D reconstruction tool is perfectly available in our remote control application. Fig. 1a and Fig. 1b show an example of 3D reconstruction using this technique.The results above described demonstrate that it is possible to remote control a SEM on public network, both for conventional and not conventional operations, even if the video streaming is affected by network limits. Starting from this point, a new research project has taken place. The topics of this project are more than one: on one side it is important to reach the real-time video streaming on public network, on the other side it will be useful to realize a structure where share instruments though tools for conventional and not conventional remote operations on public ...
