near point of convergence
Also called NPC, convergence near point, push-up convergence
The near point of convergence is the closest point at which the eyes can hold binocular fixation on a target moved in along the midline. Beyond that point one eye drifts outward, which is called the break, and the patient may see double.1,2 The break and the recovery are recorded in centimeters from the spectacle plane.1,2
The near point of convergence differs from the near point of accommodation: in older patients the target blurs before it doubles, and convergence is still measured through the blur.3
A receded or receding near point is the hallmark of convergence insufficiency, so the test is repeated four or five times, and with a red lens over one eye, to unmask a fragile binocular system.4
More detail
The demand for convergence rises as the target approaches. When the convergence available from fusion and accommodation runs out, one eye gives up fixation, and that eye is usually the non-dominant one. The point lies roughly in the plane of the eyes' centers of rotation.2 Norms differ by text, from about 5 cm to 10 cm for the break.1,2,3 An accommodative target is used first, and a penlight with a red lens follows when the break lies beyond about 5 cm.5 The near point of convergence also differs from fusional convergence amplitude, which is measured with prism at a fixed distance.
Sources (5)
- Kanski, Clinical Ophthalmology (2024), ch. 18
- von Noorden and Campos, Binocular Vision and Ocular Motility, ch. 12
- Pickwell's Binocular Vision Anomalies, ch. 2
- AOA, Care of the Patient with Accommodative and Vergence Dysfunction
- Carlson and Kurtz, Clinical Procedures for Ocular Examination, ch. 2
Reviewed October 2026
Related terms
Nearby in the glossary
- near point of convergence
- negative relative accommodation
- neutral density filter test
- nystagmus