2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/90294Quantum-limited estimation of an optical phase using adaptive (i.e. real-time feedback) techniques is reviewed. One case is explored in detail, as it can be understood using only elementary concepts such as photonic shot-noise and error analysis. Very recent experimental results are discussed.5 pages, to appear in the Australian Optical Society News. A very elementary treatmentQuantum Physicstext