This project will develop a flexible longitudinal electron optical system based on high-precision radio-frequency cavities for short and intense electron bunch compressions, both in the energy and time domains. The proposed system is designed to be inserted into an existing transmission electron microscope column to upgrade its temporal resolution. Active phase-space control enables broad ranges of material, nanoscience and technologies applications involving highly demanding ultrafast core-level spectroscopy and ultrafast single-shot material research. The high-dose mode is currently not feasible in commercial systems. While the basic concept has been demonstrated in a customized electron optical column, adapting the same technologies into an existing electron microscope will require delicate design and laboratory tests to ensure robust performance. Niowave, Inc. built the resonant cavity used as a radio-frequency buncher at the test facilities at Michigan State University that were used to demonstrate the concepts of active space-charge control. In this SBIR/STTR project, Niowave and MSU will partner to develop the next realization of this radiofrequency (RF) lens and make this technology available as a drop-in upgrade for existing commercial electron microscopes. This realization would revolutionize the future of electron microscope design, and could even transform an aging fleet of steady-state electron microscopes into powerful ultrafast imaging and spectroscopy instruments. These systems would be widely used in industrial and academic settings for material characterizations.