Retinal Damage Mechanisms for Ultrashort Laser Exposure

The Air Force has led a research effort to investigate the thresholds and mechanisms for retinal damage from ultrashort laser pulses [i.e. nanosecond (10−9 sec) to femtosecond (10−15 sec) pulse durations] for the past several years. The outcome is a recommendation for the establishment of maximum permissible exposure limits in the visible and near infrared. We review the progress made in determining trends in retinal damage1 from laser pulses from one nanosecond to one hundred femtoseconds duration at visible and near-infrared wavelengths including variations in spot size and number of pulses. We discuss the most likely damage mechanisms operative in this pulse width regime and discuss relevance to laser safety.The Air Force has led a research effort to investigate the thresholds and mechanisms for retinal damage from ultrashort laser pulses [i.e. nanosecond (10−9 sec) to femtosecond (10−15 sec) pulse durations] for the past several years. The outcome is a recommendation for the establishment of maximum permissible exposure limits in the visible and near infrared. We review the progress made in determining trends in retinal damage1 from laser pulses from one nanosecond to one hundred femtoseconds duration at visible and near-infrared wavelengths including variations in spot size and number of pulses. We discuss the most likely damage mechanisms operative in this pulse width regime and discuss relevance to laser safety.