An automated portable night vision testing system.

This report describes a new testing system designed to assess night vision parameters of the military population in the field, and to quantify the effects of various environmental stress factors, such as extended exposure to high altitude, on the dark adaptation process. The instrument is based on an established procedure for dark adaptation measurement in which the subject continuously adjusts the threshold luminance of a recurrently flashing stimulus. The device described here represents a modernized version of the original technique, which features an automated testing procedure and provides for computerized data translation of the dark adaptation function. It also offers the advantages of rugged construction and field portability not available in clinical style instruments.