3 Metre Snellin Eye Chart. Suitable for opthalmologists, optometrists & general vision assessment in limited space environments
The wall-mounted Snellen eye chart is suitable for use by eye care professionals and others to measure visual acuity.
The 3 Metre viewing distance makes this chart suitable for smaller offices, mobile clinics and other spaces where standard 6m viewing length is not possible.
Suitable for ophthalmologists and optometrists as well as for approximate assessment of vision, e.g. in a primary-care physician's office or motor registration office.
In the most common acuity test, a Snellen chart is placed at a standard 3 or 6-metre distance, where the symbols on the line representing "normal" acuity subtend an angle of five minutes of arc, and the thickness of the lines and of the spaces between the lines subtends one minute of arc. This line is designated 20/20 (US) or 6/6 (non-US), and is the smallest line that a person with normal acuity can read.
The contrast between letters and background provided by this chart satisfies all relevant clinical standards, including BS4274-1:1968, which dictates that (a) The luminance of the presentation shall be uniform and not less than 120 cd/m2m, and (b) Any variation across the test chart shall not exceed 20%.
The chart’s Optotype (letter/symbol) geometry meets relevant clinical requirements for line thickness and white space dimensions.