Visual interference effects include:

1. Flash blindness - A visual interference effect that persists as an afterimage after the source of illumination has ceased.
2. Glare – An obscuration of an object in a person’s field of vision due to a bright light source located near the same line of sight.
3. Afterimage - A transient image that persists in one’s visual field after a bright source of illumination has been removed.
4. Startle – The involuntary reaction to an unexpected event that alters mental, physical, and visual activities and diverts selected attention away from the normal primary tasks of an individual. The startle response can be broken into four specific categories: Distraction, Disruption, Disorientation, and Operational Incapacitation.
   - Distraction – Momentary attention shift from primary tasks due to sudden exposure to a bright light source. This effect may not be readily identified by the Service member and should be asked specifically.
   - Disruption – Interference or interruption of critical tasks or task sequences that extend the shift of attention from primary tasks requiring selective attention.
   - Disorientation – Losing perspective in the relationship between the direction of travel and surroundings. Can include loss of both spatial orientation and situational awareness. Disorientation can occur simultaneously with distraction, disruption, and startle.
   - Operational Incapacitation – An individual’s loss of spatial orientation and loss of situational awareness in reference to the outside world. In the case of aviation, a pilot that becomes operationally incapacitated should immediately transfer control of their aircraft because they can no longer reliably discern or control the aircraft.

The natural aversion response to bright light sources limits exposure to visible wavelength lasers to about 0.25 seconds. Although exposure may be limited to a fraction of a second by your ability to blink or turn away from the offending light source it does not provide absolute protection from injury.

Incident with Suspected Ocular Injury

An ocular injury can result from any laser wavelength if sufficient power is delivered to the eye. The affected structure within the eye varies with wavelength. Lasers emitting in the far ultraviolet, UV-B and UV-C (180-315 nm), and far infrared, IR-B and IR-C (1400 nm – 1 mm), are absorbed by the cornea. Near ultraviolet, UV-A (315-400) wavelengths are absorbed by the lens of the eye. Visible (400-700 nm) and near infrared, IR-A (700-1400 nm) wavelengths are absorbed by the retina. The spectral region 400-1400 nm is commonly referred to as the retinal hazard region. Laser output power, or energy, is an important determinant for injury potential, as is the duration of the exposure and the exposed person’s location relative to the laser source exit aperture.