Peripheral and central vision
Short answer
A visual field test checks what you can see around a fixed point, including peripheral vision. Clinical perimetry maps light sensitivity at different locations.
This guide explains the examination and its report; a browser demonstration cannot rule out field loss or replace a professional assessment.
In detail
Reading an eye chart and checking your visual field answer different questions: detail at the point you look at versus sensitivity across an area. Clinicians choose the test pattern, control the viewing conditions and interpret the results alongside the rest of your eye examination.
A map samples a defined region; it does not necessarily test every part of your peripheral vision.
Examination background: National Eye Institute — parts of a dilated eye exam; AAO EyeWiki — standard automated perimetry.
A visual field eye test examines vision away from the point where you are looking, as well as central areas when the chosen test includes them. The National Eye Institute distinguishes it from the visual acuity test, which asks you to read letters. Clear central detail alone does not describe your entire field.
Clinicians use field testing as part of investigating and monitoring problems involving the retina, optic nerve or visual pathways. The test contributes evidence to an examination; it does not explain the cause of a change by itself. This is why a field report is interpreted with your history and other findings.
Sources: National Eye Institute — parts of a dilated eye exam; Guy’s and St Thomas’ NHS — visual field eye test.
A quick field check, a threshold test and an online illustration have different roles. The clinician chooses the method to answer a particular question about your vision.
In a typical automated test, the technician positions you at the instrument and tests each eye separately. You keep your gaze on a central marker while lights appear elsewhere, pressing the response button when you see one. The brightness changes to investigate sensitivity, so missing very dim lights is expected.
Bring your current glasses and tell the technician about difficulty seeing the fixation target or staying comfortable. Keep your head still and follow the response instructions rather than searching for the lights. Blink normally, and ask for a pause or explanation if needed. Guessing based on machine sounds will not help the measurement.
Sources: Cambridge University Hospitals — visual fields; Guy’s and St Thomas’ NHS — visual field eye test.
Not every test covers the same area. Perimetry programs use different point layouts, and a central-field program is not a complete survey of the far periphery. The pattern name matters when someone describes a report simply as a peripheral vision test.
For example, ZEISS describes 24-2C as a pattern with additional central points compared with 24-2. This is a choice about where to sample, not a better-or-worse score for the person taking it. Ask which region was tested and whether that program addresses the reason for your appointment.
Sources: AAO EyeWiki — standard automated perimetry; ZEISS — Humphrey Field Analyzer 3 and test patterns.
A browser activity may demonstrate noticing a target away from where you look, but that is not enough to establish a normal visual field. The practical limits follow from what clinical perimetry controls: target properties, viewing geometry, a defined test area and fixation.
Moving closer changes the visual angle covered by a screen. Display settings change target visibility, and looking directly at a flashing target changes the task. A homemade clicking game therefore cannot inherit the evidence for a clinical instrument. Any home-monitoring system must be judged on its own validation and the clinician’s instructions; this site does not offer a clinical field test.
Sources: ZEISS — Effective Perimetry, Field Analyzer Primer (PDF); Cambridge University Hospitals — visual fields.
A report summarizes measured responses and comparisons with a reference population. These common Humphrey report terms help you discuss it with your clinician; they do not provide an automatic diagnosis.
Report terminology: ZEISS — Effective Perimetry, Field Analyzer Primer (PDF).
Take the complete report to the appointment rather than judging one shaded patch. Useful questions are which eye and program were tested, whether the run was reliable, and whether comparison with an earlier result or a repeat test is needed. Different patterns should not be compared as if they sampled identical locations.
Explore guides and experiences for contrast, depth, sharpness and color. Each entry explains what it can tell you before you begin.
A concern about missing areas of vision needs professional assessment, even if a home activity seems easy.
Last reviewed September 12, 2026. Educational guide only. This page does not measure visual fields, interpret an individual report or establish medical or legal eligibility.