Optics2026-02-281 minarXiv:2603.00572expressHow a Light Beam Is Tailored to Brain DepthThe laser beam in a three-photon microscope works like a flashlight shining through murky water. The deeper you need to illuminate, the more the water scatters light and the dimmer the picture gets.Qi Hu·Jingyu Wang·Huriye Atilgan·Armin Lak·Martin J. BoothRobert HookeSerge HarocheRoy Glauberoptical microscopyWeakly Supervised Learninglaserlens👍👎☆SimplePopularAdvanced