An Examination of the Validity of the Equivalent Background Principle for Predicting Optical Radiation Flash Blindness Effects.
Abstract
We reviewed the light adaptation literature in an attempt to reconcile conflicting reports about the validity of the equivalent background principle (EBP) as a means of characterizing the adaptive state of the retina. The flashblindness model of the AL/OEO Integrated Personnel Effects Model (ILPEM), effectively a dark adaptation function, relies on the EBP to relate the afterimage from an intense light exposure to a hypothetical 'background' of uniform luminance that fades with time. This relationship, if true, makes it convenient to estimate the recovery of visual sensitivity after optical radiation exposure. However, this review found that the data do not support the validity of the EBP, especially for photopic vision. A test of the ILPEM flashblindness model showed weakness in its predictive validity as well. Using the flashblindness model to quantitatively fit two sets of dark adaptation data, we found significant deviations between the predicted and actual recovery times to visual targets. An alternative model was found to be more accurate in predicting the results of the two data sets.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1997
- Accession Number
- ADA336461
Entities
People
- Robert Kang
- William Kosnik
Organizations
- TASC, Inc