Maximum field of vision:

Visual field is a three-dimensional area of a subject's surroundings that can be seen at any one timearound an object of fixation. Extent of visual field ( measured with 5 mm of white object): Superiorly 50deg(Least due to presence of Frontal Bone )Inferiorly 70deg (restricted by the maxillary prominence) Nasally 60deg (restricted by the nose) Temporally 90deg(Max as macula is physiologically on nasal side) Small pa of temporal field lacks bilateral representation in the visual pathway - called temporal crescent (60-100 degrees along horizontal meridian) The field for blue and yellow is roughly 10deg less and that for red and green colour is about 20deg less than that for white. Perimetry with a red colour object is paicularly useful in the diagnosis of bitemporal hemianopia