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Contrast Sensitivity Test

Full Version

This book is available for download with iBooks on your Mac or iOS device. Multi-touch books can be read with iBooks on your Mac or iOS device. Books with interactive features may work best on an iOS device. iBooks on your Mac requires OS X 10.9 or later.


This iPad-based letter contrast sensitivity test is similar in principle to the well-established Pelli-Robson Chart and Mars Letter Contrast Sensitivity Test. 
The letters have all been calibrated for the Retina Display.
The iPad test presents two letters per page and in 0.1 log unit steps. Thus scores should be equivalent to those obtained with the Pelli-Robson Chart. The test uses the same 10-letter set as the Bailey-Lovie Visual Acuity Chart.  
Letter contrast sensitivity testing is fast to administer and easy for patients to understand, due to its similarity to visual acuity charts. Letter-based tests have been shown to be more repeatable than printed tests using gratings and are widely used in large clinical trials supported by the US National Institutes of Health.
Unlike other tests, the test requires no external lighting and runs on the ubiquitous iPad without need for special software or calibration. The test utilizes the high quality iPad screen to produce letters with contrasts as low as 0.5%, below that visible to the average patient.
An un-validated student version with one letter per contrast level is also available from the iTunes store. 
For more information visit ""

What's New in Version 1.2

Contrast Tweaks


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Contrast Sensitivity Test
View in iTunes
  • $39.99
  • Available on iPad, iPhone and Mac.
  • Category: Medical
  • Published: Sep 17, 2015
  • Publisher: Ridgevue Vision
  • Seller: Ridgevue Vision LLC
  • Print Length: 54 Pages
  • Language: English
  • Version: 1.2
  • Requirements: To view this book, you must have an iPad with iBooks 2 or later and iOS 5 or later, or an iPhone with iOS 8.4 or later, or a Mac with OS X 10.9 or later.

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