To create high-resolution, 3D images of tissues such as the brain, researchers often use two-photon microscopy, which involves aiming a high-intensity laser at the specimen to induce fluorescence excitation. However, scanning deep within the brain can be difficult because light scatters off of tissues as it goes deeper, making images blurry.
Click here for original story, Microscopy technique makes finer images of deeper tissue, more quickly
Source: Phys.org