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FLEX acuity

Professional, mobile visual acuity app for iPAD

Professional FLEX visual acuity assessment

Now take the visual acuity test to the patient rather than the patient to visual acuity. FLEX dynamically scales from 13″ to 20′ (33 cm to 6 m) on-the-fly.  Perfect for assessing irregular distances such as intermediate / computer distances (e.g. 50 or 66 cm). Full library of literate, illiterate and global optotypes with a rich assortment of isolation features and randomization driven by one-touch and gestures. Presbyopic?  Now a one-touch bubble previews the smallest letters for instant verification of letters read.

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One-touch masking / isolation

  • reveal of chart overlays
  • single lines
    (vertical + horizontal)
  • single letter (with red or black crowding bars or none)
  • reverse contrast
  • one touch, pop-up magnifier (very useful for smallest letter verification for presbyopic test administrators)
  • simple demo for HOTV and pediatric optotypes for comprehension assurance

Intuitive gesture controls

  • larger – smaller optotypes
    swipe up or down middle zone
  • letter randomization:
    double tap
  • move highlight line
    swipe up or down outer zones
  • reveal of selection trays
    • overlay
    • optotypes

Dynamic Optotypes

  • instant, flexible test distances from 0.33 to 6 meters (14 inches to 20 feet)
  • fantastic for assessment of non-typical distances such as computer screen
  • instant, flexible Notation systems: 20/xx, LogMar, Decimal, and Metric
  • measurement convention switch selectable
  • enhanced logic for resolution dependence of smallest optotypes at closest test distances


Comprehensive Sloan specification optotype library


  • Sloan letters
  • Sloan numbers
  • Snellen letters


  • Tumbling E’s
  • Landolt C’s
  • HOTV
  • Konan Kids pediatric


  • Japanese
  • Korean
  • Arabic
  • Greek
  • Hebrew
  • Russian

Download and use on your iPAD now!