For examination of the entire ocular fundus and the iridocorneal angle. The advantage of a longer mirror is that it often permits binocular observation of the lateral sections of the ocular fundus.
Zone 1: Lens examination of the ocular fundus in the 30° zone, mostly with a magnification of 10x.
Zone 2: Mirror with a declination of 73°. Observation of the zone outside of the 30° range.
Zone 3: Mirror with a declination of 66° observation of the peripheral sections of the ocular fundus, and under favorable conditions, also of the ora serrata.
Zone 4: Mirror with a declination of 59° observation of the vitreous body and ocular fundus sections neighboring the ora serrata as well as a gonioscopic examination.