**4. Conclusion**

In the last years, the R&D of SPADs technology has proceeded at great sped. The main challenge towards imaging devices is geometry and process optimization to yield high compactness while not excessively degrading performance.

On the other hand to make a Time Resolved Camera a compact object available on the market, many efforts have still to be made, in terms of identifying the best readout strategies and ancillary circuitries.
