Patent Document ID: 9545224
Application ID: 13883330
Patent Flag: 1

Claim One:
1. A method of measuring concentration based fitness for duty of a user in advance of implementation of the duty based on voluntary blinks of the user, comprising: providing a source of visual stimulus; presenting from the source instances of brief visual stimuli separated by intervals of about 1.5-3 seconds; monitoring voluntary blinks in response to the brief visual stimuli; and determining the fitness for duty that measures impairment based on at least: measures of voluntary blink latency in response to the brief visual stimuli, the product of the amplitude to velocity ratio of eyelid closing and opening movements during voluntary blinking in response to the brief visual stimuli, the duration of voluntary blinks in response to the brief visual stimuli, and the failure to respond appropriately with a voluntary blink in response to each of the brief visual stimulus; assessing based on the measured fitness for duty whether the user is unfit to commence the duty.