For testing visual acuity in normal subjects, background luminance does not have a clinically relevant impact. The effect of chart luminance on visual acuity for photopic vision has been reported and doubling the luminance level improves only one letter in a test of five letters per row in the range from 40 cd/m2 to 600 cd/m2. However, in some procedures such as in multifocal procedures, the background brightness might have a higher impact on the results, specially for testing contrast sensitivity.
The Pico Palette device has been originally designed for measuring color by reflection. However, we have adapted this device for accomplishing a new functionality: to evaluate the relationship between digital levels and luminance (cd/m2) in IOS devices (iPhone and iPad). Thanks to this device you can obtain in less than 4 minutes:
1.- The brightness you have to select in test-eye.com Apps for the background luminance you desire (from 80 cd/m2 to 300 cd/m2).
2.- The Gamma function of the RGB channels in order to achieve a highest precision in the measurement of Contrast Sensitivity.
The outcome information can be then used in the Apps of test-eye.com for testing vision in order to have a personalized calibration of the App for your device.
The application has been designed to be used with an external hardware PICO.
Minor bugs corrections
Up to six family members will be able to use this app with Family Sharing enabled.