In a glare testing, how many controlled degrees of light does the BAT test deliver when the eye is viewing a Snellen target?

The BAT test, or glare testing, is designed to evaluate the visual performance of the eye under conditions of excessive brightness or glare. When a person views a Snellen target during the BAT test, it specifically delivers three controlled degrees of light. This setup allows for a standardized assessment of how glare affects readability and visual clarity at different light levels, which is essential in determining the impact of glare on visual acuity. The three degrees create a compelling method to measure glare sensitivity and enable the evaluation of the subject's ability to adapt to varying luminance conditions while focusing on the target.