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Digital visual acuity test using calculator-type numerals with geometric gradation.

J M Lewis·T J Smith
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Abstract

The authors have developed a visual acuity test using numeric optotypes with dimensions similar to numerals used in liquid crystal displays (LCDs) or light-emitting diodes (LEDs). Each optotype has the same external configuration to minimize variation in recognition difficulty. The test is designed with geometric gradation and an equal number of optotypes per line, which facilitates the recording of acuity in decimal notation. This allows convenient data entry and computer analysis of acuity results. Chart inversion provides greater flexibility by altering the numeric sequence. This new digital acuity test (DAT) compares favorably to acuity tests that have Sloan or Snellen letters as optotypes.

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BibTeXRIS

J M Lewis, T J Smith. 1987. Digital visual acuity test using calculator-type numerals with geometric gradation.. https://doi.org/10.1016/s0161-6420(87)33486-4

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