near point of convergence
Also called NPC, convergence near point, push-up convergence
The closest point at which the eyes can hold binocular fixation on a target moved in along the midline. Beyond it one eye drifts outward, which is called the break, and the patient may see double; the break and the recovery are recorded in centimeters from the spectacle plane1,2.
It differs from the near point of accommodation: in older patients the target blurs before it doubles, and convergence is still measured through the blur3. 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 system4.
More detail
The demand for convergence rises as the target approaches; when the convergence available from fusion and accommodation runs out, one eye, usually the non-dominant one, gives up fixation. The point lies roughly in the plane of the eyes' centers of rotation2. Norms differ by text, from about 5 cm to 10 cm for the break1,2,3. An accommodative target is used first, and a penlight with a red lens when the break lies beyond about 5 cm5. It 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