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Far Point of the Eye

The far point of the eye is the object point imaged by the eye onto the retina in an unaccommodated eye. If a corrective lens is used to correct for myopia, the lens has its secondary focal point coincident with the far point of the eye.

• The far point of the emmetropic eye is at infinity.
• Myopia exists if, without accommodation, a point at infinity is imaged in front of the retina (in the vitreous). The stimulus on the retina is therefore not a point, but a blur circle. Moving the object closer to the myopic eye, until the image is a point focus on the retina, establishes the far point of the eye.
• Hyperopia exists, if without accommodation, an object point at infinity is imaged neither in the vitreous nor on the retina, but theoretically, behind it.