Fundus autofluoresence uses the natural properties of lipofusin, a molecule within the retina that is formed from the breakdown of photoreceptors..  When subjected to blue light, these molecules emit a yellow-green light that is captured by the camera to create an image.  Autofluoresence is important with imaging central serous chorioretinopathy, choroidal nevi (moles), retinal toxicities, and uveitis.