This International Standard, together with ISO 15004-1 and ISO 15004-2, specifies requirements and test methods for slit-lamp microscopes to provide slit illumination and observation under magnification of the eye and its adnexa. This International Standard is not applicable to microscope accessories, e.g. photographic equipment and lasers. This International Standard takes precedence over ISO 15004-1 and ISO 15004-2, if differences exist.