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3 Classic Methods for Identifying Your Dominant Eye

Sighting eye dominance is associated to an increased guidance of one eye in tasks involving a line of sight and visuo-motor coordination, like aiming at a target with a gun. Indeed, to determine the dominant eye patients perform

alignment tasks: patient’s sight must be aligned with a target and a third object (usually a finger or a hole). The three most popular methods to assess what is the dominant eye are the Miles method, the Point test and, above all, the Dolman method (hole in the card).

These early methods, while widely used, have a limitation: These tests treat eye dominance as a fixed, binary trait rather than a spectrum.

Miles Method

Man using Parson’s device (Manuscope) to detect his dominant eye
  1. The patient looks at a target card with two eyes, through a funnel-shape apparatus called Parson’s manuscope
  2. The cone base fits about the forehead, avoiding light comes in.
  3. When the target is moved far enough (2- 3 meters) the apparatus forces sighting through a single eye, while the subject has still the impression of using both eyes (if he had to choose what eye to use, the test would measure eye preference).
  4. For the examiner is easy to determine what eye he is using, that is the dominant eye.
Parson’s device (Manuscope) for eye dominance detection

Point Test

Point Test showing dominant eye open versus closed for eye dominance detection

Hole in the Card (or Dolman Method)

Hole-in-the-card method showing target shift with dominant eye open or closed
Hole-in-the-card method illustrated by sight projections of the hole on the target plane – part 1
Hole-in-the-card method illustrated by sight projections of the hole on the target plane – part 2
Hole-in-the-card method illustrated by sight projections of the hole on the target plane – part 3
Hole-in-the-card method illustrated by sight projections of the hole on the target plane – part 4