The gridpix detector: history and perspective

In 2000, the requirements for a large TPC for experiments at a new linear collider were formulated. Both the GEMand Micromegas gas amplification systems had matured, such that they could be practically applied. With the Medipix chip, a pixel-segmented anode readout became possible, offering an unprecedented level of granularity and sensitivity. The single electron sensitive device is a digital detector capable to record and transfer all information of the primary ionization, provided that it can be made discharge proof.