Background Illumination with pivoting support FI 01p A bright and even background illumination is the most important key for all imaging applications on the Slit Lamp. The pivoting background illumination for advanced users allows the creation of the exact right lighting condition for every imaging situation. Background Illumination FI 01f A bright and even background illumination is the most important key for all imaging applications on the Slit Lamp. The fixed background illumination provides homogeneous and bright light for basic imaging application.