Fonlow Apps

Optically precise optotypes of tumbling E to measure visual acuity

Prevention is better than cure. Designed for children older than6,parents with young children, and general practitioners, thisappdisplays optically precise optotypes of ETDRS Chart for youtomeasure distant visual acuity accurately in order todetectnearsightedness or myopia and early, so you can takepreventivemeasures and seek help from medical professional early topreventpseudomyopia from becoming myopia, or preventnearsightedness fromgetting worse. Predefined Test Distances: * 6,5, 4, 3, and 2meters * 20, 15, 12, 10, 6 feet At exactly 6 metersaway from the“patient”, the optotypes on the 6/6 line (Decimal 1.0or LogMar0.0) shall subtend 5 minutes of arc, which means that thechartshould be sized such that these optotypes are 8.73mm tall, andthetopmost (Snellen Fraction 6/60, Decimal 0.1, or LogMar1.0)optotypes should be 87.3 mm tall. At exactly 20 feet away fromthe“patient”, the topmost optotypes should be 88.7 mm tall, because20feet equals 6.096 meters. Scenarios: 1. "Doctor" and "Patient".2.Self-diagnosis with a mirror. 3. Self-diagnosis with aBluetoothkeyboard. 4. Self-diagnosis within arm's reach. Notations：1.Decimal (0.50) 2. Fraction (20/40) 3. LogMAR (0.30) 4.Fraction(5/10) 5. Fraction (6/12) 6. MAR (2) 7. VAS or VAR (85)Test Modes:1. Autoplay 2. Manual In Autoplay, the app calculatesthe score.For LogMAR notation, the score is (LogMAR value of thebest lineread) + 0.02 x (number of optotypes missed). And themaximum missedis 3. For VAS notation, the score is an inversion ofthe logMARscale, based on VAS=100-50xlogMAR. For other notations,the scoreis the notation value of the best line read and optionallyminusnumber of optotypes missed, and the maximum missed is 2.Bydefault, setting "Play Interval Until Next Optotype" isnone.Available intervals in second: 2, 4, 6, 8, and 10. If the"patient"could not recognize the optotype within the interval, thiscounts amiss. Through enabling “Record Scores” in Settings, you cankeeptrack of the progression of your visual acuity. Visualacuityscores of multiple testees could be recorded. Visual AcuityScore(VAS) is an inversion of the logMAR scale, basedonVAS=100-50xlogMAR. It is more intuitive since highervaluesindicate better visual acuity. In the scores review, score100 inblue indicates the reference standard, scores above 100 ingreenindicates no myopia, while scores below 100 in red mayindicatemyopia. Testing for myopia takes several procedures and thefirststep is often to check distant visual acuity through avisualacuity chart. And the decrement of visual acuity may indicatethedevelopment of myopia. Disclaimer: While this app may replaceETDRSChart in print, however it cannot replace doctors andoptometristswho carry out comprehensive tests for your eyes. Pleasevisitoptometrists regularly and seek help from medical professionalatearly signs of visual acuity problems.

Optically precise optotypes of Snellen Chart to measure visualacuity

Test distant visual acuity to find early sign of myopia.

Test who has better distant vision and responsiveness between twoplayers.