Non-linear optical hazards from near-infrared ultrafast laser pulses in ocular tissue

Ultrafast lasers are capable of generating extremely high peak powers and inducing non-linear optical phenomena that may be hazardous to sensitive ocular tissue. The generation of broadband supercontinuum light from ultrafast near infrared (NIR) lasers is of particular interest because of the potential damaging effects on both the cornea and retina. Freshly excised porcine eyes and an artificial model eye proved to be suitable systems to investigate non-linear optical phenomena due to the similarity in size and optical properties to the human eye. A tunable optical parametric amplifier (OPA) with a nominal pulse with of 100 femtoseconds generated all laser exposures in the 1200-1500 nm range. A fiber-based spectrometer introduced into the back of excised porcine eyes through a small incision in the sclera and placed at the retinal plane measured spectral broadening of the NIR femtosecond laser pulses. Changes in the spectral profile of the supercontinuum light were observed at multiple pulse energies and monitored dynamically as the position of the beam focus was adjusted with respect to the corneal surface. Further consideration of non-linear optical hazards may be required to ensure the safe use of ultrafast lasers as they become more prevalent in life sciences, telecommunications, industrial processing, and biomedical applications.Ultrafast lasers are capable of generating extremely high peak powers and inducing non-linear optical phenomena that may be hazardous to sensitive ocular tissue. The generation of broadband supercontinuum light from ultrafast near infrared (NIR) lasers is of particular interest because of the potential damaging effects on both the cornea and retina. Freshly excised porcine eyes and an artificial model eye proved to be suitable systems to investigate non-linear optical phenomena due to the similarity in size and optical properties to the human eye. A tunable optical parametric amplifier (OPA) with a nominal pulse with of 100 femtoseconds generated all laser exposures in the 1200-1500 nm range. A fiber-based spectrometer introduced into the back of excised porcine eyes through a small incision in the sclera and placed at the retinal plane measured spectral broadening of the NIR femtosecond laser pulses. Changes in the spectral profile of the supercontinuum light were observed at multiple pulse energies and ...