LINK NV-100

Binocular investigation at the distance people actually read

The LINK NV-100 is a near vision tester for refractive and binocular investigation at the reading distance, with the head and eyes in normal posture. It covers fixation disparity, foveal suppression, near point of convergence and presbyopic additions, and weighs just 780g.

Sections

Vision Screeners

Investigating Reading Discomfort and Headaches

Patients reporting headaches, reading fatigue or intermittent blur at near are a regular presentation, and a distance refraction frequently comes back unremarkable. The cause is often binocular and only shows itself at the working distance. Fixation disparity testing, near point of convergence and evaluation of the accommodation to convergence relationship together give the practitioner the means to find it rather than concluding that nothing is wrong. Symptoms without findings frustrate patient and practitioner alike.

Presbyopic Addition Determination

Near additions are determined at the distance the patient will actually use them, with the head and eyes in natural posture. That matters because a reading addition worked out in an artificial position may not suit the way someone holds a book or sits at a desk. Near vision astigmatism testing sits alongside, so the near correction is refined properly rather than assumed from the distance prescription.

Heterophoria and Binocular Assessment

Cover test targets, foveal suppression evaluation and the fixation disparity test give a coherent approach to heterophoria at near. Being able to quantify foveal suppression rather than merely observe it means the finding can be recorded, compared at a later visit and used to judge whether a prescribed prism or exercise regime is achieving anything measurable.

Portable and Domiciliary Examination

At 780g and running from three AA cells, the unit imposes no requirement for mains power or installation. Domiciliary visits, care home rounds and outreach clinics can include proper near binocular investigation rather than a simplified version, and the unit slips into a bag alongside whatever else the visit requires. Equipment that travels easily is equipment that actually gets taken along.

Findings a Distance Test Cannot Produce

Near binocular problems are the ones most often missed, because a distance refraction genuinely looks normal in a patient whose difficulty appears only when converging and accommodating together. A unit designed for the working distance, in natural posture, gives the practitioner the means to investigate the complaint properly instead of reassuring somebody whose symptoms are entirely real. Reassurance is no substitute for a proper investigation. Investigating properly is what separates a thorough examination from a quick one.

Measurements Rather Than Impressions

Quantifying foveal suppression, near point of convergence and amplitude of accommodation turns observations into recorded values. That matters at the next appointment, when the question is whether anything has changed, and it matters when justifying a prism prescription or an exercise programme to a patient who wants to know why it was recommended. A recorded value can be revisited; an impression cannot. Justifying a prescription is easier with figures behind it.

Capability That Costs Little Space

A unit weighing 780g and running from ordinary cells adds a full near binocular assessment to a practice without occupying bench space, requiring installation or drawing power. Few additions to a consulting room offer that much clinical reach for so little physical and practical commitment. Clinical reach and physical footprint rarely trade this favourably.

Fixation Disparity Testing

A fixation disparity test identifies uncompensated heterophoria and motor eye dominance, detecting a binocular misalignment that remains hidden while fusion is holding it in check.

Quantitative Foveal Suppression Evaluation

Foveal suppression in heterophoria patients can be evaluated quantitatively rather than simply noted as present, which gives the finding a value that can be recorded and compared.

Near Point of Convergence

Near point of convergence is measured directly. A receded near point is a common finding in patients reporting reading fatigue, and quantifying it turns the symptom into a measurement.

Accommodation and Convergence Relationship

The relationship between accommodation and convergence can be examined, which is central to understanding why some patients struggle at near despite an accurate refractive correction.

Amplitude of Accommodation

Amplitude of accommodation is measured, including monocular measurements taken under binocular conditions, which reflects how each eye performs in the state it actually works in.

Cover Test Targets

Targets for subjective cover tests cover heterophoria and harmonious anomalous retinal correspondence, supporting assessment of how the two eyes are working together at near.

Full Near Acuity Charts

Snellen letter and illiterate E charts sit alongside reading types, so acuity can be measured at near for readers and non-readers alike using the appropriate presentation.

Portable and Battery Operated

At 220mm by 210mm by 42mm and 780g, running from three AA cells, the unit needs no mains connection and travels wherever the examination is taking place.

The LINK NV-100 near vision tester covers the part of an examination that distance equipment cannot reach. Refractive testing includes acuity by Snellen letter and illiterate E charts alongside reading types, determination of presbyopic additions and other near corrections, near vision astigmatism testing, and amplitude of accommodation including monocular measurement under binocular conditions.

The binocular section carries a fixation disparity test for uncompensated heterophoria and motor eye dominance, examination of the accommodation to convergence relationship, quantitative evaluation of foveal suppression, near point of convergence, and cover test targets for heterophoria and harmonious anomalous retinal correspondence. Test distance is 36cm, the unit measures 220mm high by 210mm wide by 42mm deep at a weight of 780g, and three ordinary AA cells power it with no mains connection required. The distant control figure of 60cm listed on the sheet is not explained and is worth clarifying, and we would ask you to confirm battery type supplied, certification status, condition and reseller and listing rights for the manufacturer trademark. For a unit of this kind the configuration question is a short one, but it is worth asking before anything is agreed. Contact Medigear.uk, a verified medical equipment supplier, and we will confirm exactly what a given unit includes before anything is agreed.

FAQ

Frequently Asked Questions

Everything buyers need to know about sourcing medical equipment through MediGear.

It identifies uncompensated heterophoria and motor eye dominance. A heterophoria held in check by fusion produces no obvious deviation, yet the effort of holding it can cause real symptoms at near. Testing fixation disparity reveals whether that compensation is breaking down under the demands of reading. Symptoms often appear well before any deviation becomes visible.

Because near difficulties often appear only when accommodation and convergence work together, which a distance refraction does not reproduce. Testing at 36cm with the head and eyes in natural posture examines the visual system in the state the patient complains about, rather than inferring near performance from distance findings. Posture affects the demand placed on convergence considerably.

Fixation disparity, examination of the accommodation to convergence relationship, quantitative evaluation of foveal suppression in heterophoria patients, near point of convergence, and targets for subjective cover tests covering heterophoria and harmonious anomalous retinal correspondence. Between them they cover the near binocular picture thoroughly.

Snellen letter charts, an illiterate E chart and reading types set in a serif typeface. That combination covers literate and non-literate patients, and the reading types allow near acuity to be assessed with continuous text rather than isolated letters alone. Continuous text reflects the act of reading more faithfully than isolated letters do.

The unit provides for quantitative evaluation of foveal suppression in heterophoria patients, which means the finding is given a value rather than simply noted. A recorded figure can be compared at a subsequent visit to judge whether a treatment is having any measurable effect. Comparable values across visits are what make progress visible.

Test distance is 36cm. The specification also lists a distant control figure of 60cm, though the sheet does not explain what that governs. We would ask Medigear.uk to clarify the second figure rather than guess at its meaning on your behalf. Confirming it beforehand avoids any confusion during setup.

Three AA cells, so no mains connection is required at all. That makes the unit genuinely portable for domiciliary visits and outreach work, and removes any question of where a power point sits relative to where the patient is seated. Cells are inexpensive and available anywhere, which suits visiting work.

The unit measures 220mm high by 210mm wide by 42mm deep and weighs 780g. Those proportions suit handheld use during an examination and pack easily into a bag, which is what makes it practical for visits away from the main premises. Nothing about it requires installation or a dedicated surface.