Recent research has shown that many of the yellow enhancement filters built into slit-lamps or hand held are not optimal in removing unwanted illuminating blue light while allowing all illumination from the excited fluorescein molecules to be viewed (Peterson, Wolffsohn & Fowler, 2006. American Journal of Ophthalmology). Hence this new filter by Bausch and Lomb & Aston University is designed to reduce these problems and enhance your viewing of fluorescein dye.