MonPack One is a multifunction stimulator combining, in a compact system, all the tests needed for a complete, thorough evaluation of visual functions. Only one stimulator with an innovative design is needed for flash ganzfeld ERG and VEP, pattern ERG and VEP, multifocal ERG and VEP as well as sensory EOG. It is compatible with the ISCEV standards for visual electrophysiology. It includes a LED backlight with luminance feedback (patented) insuring that the luminance of pattern ERG and pattern VEP stimulations remain constant.